3,054 research outputs found

    Fostering Broad Oral Language Skills in Preschoolers from Low SES Background

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    Socioeconomic disparities increase the probability that children will enter school behind their more advantaged peers. Early intervention on language skills may enhance language and literacy outcomes, reduce the gap and, eventually, promote school readiness of low-SES (Socioeconomic Status) children. This study aimed to analyze the feasibility and effectiveness of a brief narrative-based intervention (treatment vs. control group) aimed to foster broad oral language skills in preschoolers (N = 69; Mean age = 5.5, SD = 4 months) coming from low-SES families. Moreover, it was analyzed whether children's initial vocabulary mediates the intervention's responsiveness. Results have shown that children in treatment group obtained greater gains than children in control group in almost all intervention-based measures. There is also some evidence for the generalizability of the intervention to other skills not directly trained during the intervention. Moreover, it was found that children's initial vocabulary mediates the intervention's responsiveness showing that children with high vocabulary made greater gains in higher-level components of language comprehension, whereas children with low vocabulary made higher gains in vocabulary. Taken together, our findings suggest that a relatively brief, but quite intensive narrative-based intervention, may produce improvements on broad oral language skills in preschoolers from low-SES backgrounds

    Fostering Broad Oral Language Skills in Preschoolers from Low SES Background

    Get PDF
    Socioeconomic disparities increase the probability that children will enter school behind their more advantaged peers. Early intervention on language skills may enhance language and literacy outcomes, reduce the gap and, eventually, promote school readiness of low-SES (Socioeconomic Status) children. This study aimed to analyze the feasibility and eectiveness of a brief narrative-based intervention (treatment vs. control group) aimed to foster broad oral language skills in preschoolers (N = 69; Mean age = 5.5, SD = 4 months) coming from low-SES families. Moreover, it was analyzed whether children’s initial vocabulary mediates the intervention’s responsiveness. Results have shown that children in treatment group obtained greater gains than children in control group in almost all intervention-based measures. There is also some evidence for the generalizability of the intervention to other skills not directly trained during the intervention. Moreover, it was found that children’s initial vocabulary mediates the intervention’s responsiveness showing that children with high vocabulary made greater gains in higher-level components of language comprehension, whereas children with low vocabulary made higher gains in vocabulary. Taken together, our findings suggest that a relatively brief, but quite intensive narrative-based intervention, may produce improvements on broad oral language skills in preschoolers from low-SES backgrounds

    High resolution spectroscopy of single NV defects coupled with nearby 13^{13}C nuclear spins in diamond

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    We report a systematic study of the hyperfine interaction between the electron spin of a single nitrogen-vacancy (NV) defect in diamond and nearby 13^{13}C nuclear spins, by using pulsed electron spin resonance spectroscopy. We isolate a set of discrete values of the hyperfine coupling strength ranging from 14 MHz to 400 kHz and corresponding to 13^{13}C nuclear spins placed at different lattice sites of the diamond matrix. For each lattice site, the hyperfine interaction is further investigated through nuclear spin polarization measurements and by studying the magnetic field dependence of the hyperfine splitting. This work provides informations that are relevant for the development of nuclear-spin based quantum register in diamond.Comment: 8 pages, 5 figure

    Direct Measurement of the Photon Statistics of a Triggered Single Photon Source

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    We studied intensity fluctuations of a single photon source relying on the pulsed excitation of the fluorescence of a single molecule at room temperature. We directly measured the Mandel parameter Q(T) over 4 orders of magnitude of observation timescale T, by recording every photocount. On timescale of a few excitation periods, subpoissonian statistics is clearly observed and the probablility of two-photons events is 10 times smaller than Poissonian pulses. On longer times, blinking in the fluorescence, due to the molecular triplet state, produces an excess of noise.Comment: 4 pages, 3 figures, 1 table submitted to Physical Review Letter

    Pseudospectra in non-Hermitian quantum mechanics

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    We propose giving the mathematical concept of the pseudospectrum a central role in quantum mechanics with non-Hermitian operators. We relate pseudospectral properties to quasi-Hermiticity, similarity to self-adjoint operators, and basis properties of eigenfunctions. The abstract results are illustrated by unexpected wild properties of operators familiar from PT-symmetric quantum mechanics.Comment: version accepted for publication in J. Math. Phys.: criterion excluding basis property (Proposition 6) added, unbounded time-evolution discussed, new reference

    Reduced Gutzwiller formula with symmetry: case of a finite group

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    We consider a classical Hamiltonian HH on R2d\mathbb{R}^{2d}, invariant by a finite group of symmetry GG, whose Weyl quantization H^\hat{H} is a selfadjoint operator on L2(Rd)L^2(\mathbb{R}^d). If χ\chi is an irreducible character of GG, we investigate the spectrum of its restriction H^_χ\hat{H}\_\chi to the symmetry subspace L2_χ(Rd)L^2\_\chi(\mathbb{R}^d) of L2(Rd)L^2(\mathbb{R}^d) coming from the decomposition of Peter-Weyl. We give reduced semi-classical asymptotics of a regularised spectral density describing the spectrum of H^_χ\hat{H}\_\chi near a non critical energy E∈RE\in\mathbb{R}. If ÎŁ_E:={H=E}\Sigma\_E:=\{H=E \} is compact, assuming that periodic orbits are non-degenerate in ÎŁ_E/G\Sigma\_E/G, we get a reduced Gutzwiller trace formula which makes periodic orbits of the reduced space ÎŁ_E/G\Sigma\_E/G appear. The method is based upon the use of coherent states, whose propagation was given in the work of M. Combescure and D. Robert.Comment: 20 page

    Little “We’s”: how common identities improve behavior differently for ethnic majority and minority children

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    This field experiment tested whether inducing common inclusive representations (i.e., one group, dual identity) during contact influences intergroup relations differently for ethnic majority and minority children by changing their metaperceptions and intergroup emotions differently. White (N = 113) and Black (N = 111) 8- to 10-year-old children were exposed to interactive mixed-ethnicity sessions in schools emphasizing either categorization as one group (national group), dual identity (national group with ethnic subgroups), or two ethnic groups. Overall, as predicted, for White children, one-group, but not dual-identity perceptions, improved behavioral intentions by influencing metaperceptions. For Black children, dual-identity, but not one-group, perceptions improved behavioral intentions through metaperceptions. Contrary to the expected, both dual-identity and one-group perceptions were associated with White and Black children’s intergroup emotions.info:eu-repo/semantics/acceptedVersio

    Strong Coupling of a Spin Ensemble to a Superconducting Resonator

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    We report the realization of a quantum circuit in which an ensemble of electronic spins is coupled to a frequency tunable superconducting resonator. The spins are Nitrogen-Vacancy centers in a diamond crystal. The achievement of strong coupling is manifested by the appearance of a vacuum Rabi splitting in the transmission spectrum of the resonator when its frequency is tuned through the NV center electron spin resonance.Comment: 4 pages, 3 figure
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