526 research outputs found

    Flexibility in Problem Solving: Analogical Transfer of Tool Use in Toddlers Is Immune to Delay

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    Solving problems that are perceptually dissimilar but require similar solutions is a key skill in everyday life. In adults, this ability, termed analogical transfer, draws on memories of relevant past experiences that partially overlap with the present task at hand. Thanks to this support from long-term memory, analogical transfer allows remarkable behavioral flexibility beyond immediate situations. However, little is known about the interaction between long-term memory and analogical transfer in development as, to date, they have been studied separately. Here, for the first time, effects of age and memory on analogical transfer were investigated in 2-to-4.5-olds in a simple tool-use setup. Children attempted to solve a puzzle box after training the correct solution on a different looking box, either right before the test or 24 hours earlier. We found that children (N = 105) could transfer thesolution regardless of the delay and a perceptual conflict introduced in the tool set. For children who failed to transfer (N = 54) and repeated the test without a perceptual conflict, the odds of success did not improve. Our findings suggest that training promoted the detection of functional similarities between boxes and, thereby, flexible transfer both in the short and the long term

    Transverse polarization measurement of Λ hyperons in pNe collisions at √s<sub>NN</sub> = 68.4 GeV with the LHCb detector

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    A measurement of the transverse polarization of the Λ and Λ¯ hyperons in pNe fixed-target collisions at √sNN = 68.4 GeV is presented using data collected by the LHCb detector. The polarization is studied using the decay Λ→pπ− together with its charge conjugated process, the integrated values measured arePΛ=0.029±0.019(stat)±0.012(syst),PΛ¯=0.003±0.023(stat)±0.014(syst).Furthermore, the results are shown as a function of the Feynman~x~variable, transverse momentum, pseudorapidity and rapidity of the hyperons, and are compared with previous measurements.<br/

    Comprehensive analysis of local and nonlocal amplitudes in the B<sup>0 </sup>→ K<sup>*0</sup>μ<sup>+</sup>μ<sup>−</sup> decay

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    A comprehensive study of the local and nonlocal amplitudes contributing to the decay B0→K∗0(→K+π−)μ+μ− is performed by analysing the phase-space distribution of the decay products. The analysis is based on \proton\proton collision data corresponding to an integrated luminosity of 8.4fb−1 collected by the LHCb experiment. This measurement employs for the first time a model of both one-particle and two-particle nonlocal amplitudes, and utilises the complete dimuon mass spectrum without any veto regions around the narrow charmonium resonances. In this way it is possible to explicitly isolate the local and nonlocal contributions and capture the interference between them. The results show that interference with nonlocal contributions, although larger than predicted, only has a minor impact on the Wilson Coefficients determined from the fit to the data. For the local contributions, the Wilson Coefficient C9, responsible for vector dimuon currents, exhibits a 2.1σ deviation from the Standard Model expectation. The Wilson Coefficients C10, C′9 and C′10 are all in better agreement than C9 with the Standard Model and the global significance is at the level of 1.5σ. The model used also accounts for nonlocal contributions from B0→K∗0[τ+τ−→μ+μ−] rescattering, resulting in the first direct measurement of the bsττ vector effective-coupling C9τ

    Observation of the<i> B</i><sup>+</sup><sub>c</sub> → <i>J/ψ</i>π<sup>+</sup>π<sup>0</sup> decay

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    The frst observation of the B+c → J/ψπ+π0 decay is reported with high significance using proton-proton collision data, corresponding to an integrated luminosity of 9 fb−1, collected with the LHCb detector at centre-of-mass energies of 7, 8, and 13 TeV. The ratio ofits branching fraction relative to the B+c → J/ψπ+ channel is measured to beBB+c →J/ψπ+π0BB+c →J/ψπ+= 2.80 ± 0.15 ± 0.11 ± 0.16 ,where the first uncertainty is statistical, the second systematic and the third related to imprecise knowledge of the branching fractions for B+ → J/ψK∗+ and B+c → J/ψπ+ decays, which are used to determine the π0 detection efficiency. The π+π0 mass spectrum is found to be consistent with the dominance of an intermediate ρ+ contribution in accordance witha model based on QCD factorisation.<br/

    Search for the rare decay of charmed baryon Λ<sup>+</sup> <sub></sub> into the ⁢<sup>+</sup>⁢<sup>−</sup> final state

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    A search for the nonresonant Λ+ c→pμ+μ− decay is performed using proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the LHCb experiment, corresponding to an integrated luminosity of 5.4  fb−1. No evidence for the decay is found in the dimuon invariant-mass regions where the expected contributions of resonances is subdominant. The upper limit on the branching fraction of the Λ+ c→pμ+μ− decay is determined to be 2.9⁢(3.2)×10−8  at  90%(95%) confidence level. The branching fractions in the dimuon invariant-mass regions dominated by the n, p and w resonances are also determined

    A randomised controlled trial investigating the effect of n-3 long-chain polyunsaturated fatty acid supplementation on cognitive and retinal function in cognitively healthy older people: the Older People And n-3 Long-chain polyunsaturated fatty acids (OPAL) study protocol [ISRCTN72331636].

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    The number of individuals with age-related cognitive impairment is rising dramatically in the UK and globally. There is considerable interest in the general hypothesis that improving the diet of older people may slow the progression of cognitive decline. To date, there has been little attention given to the possible protective role of n-3 long-chain polyunsaturated fatty acids (n-3 LCPs) most commonly found in oily fish, in age-related loss of cognitive function. The main research hypothesis of this study is that an increased dietary intake of n-3 LCPs will have a positive effect on cognitive performance in older people in the UK. To test this hypothesis, a double-blind randomised placebo-controlled trial will be carried out among adults aged 70-79 years in which the intervention arm will receive daily capsules containing n-3 LCP (0.5 g/day docosahexaenoic acid and 0.2 g/day eicosapentaenoic acid) while the placebo arm will receive daily capsules containing olive oil. The main outcome variable assessed at 24 months will be cognitive performance and a second major outcome variable will be retinal function. Retinal function tests are included as the retina is a specifically differentiated neural tissue and therefore represents an accessible window into the functioning of the brain. The overall purpose of this public-health research is to help define a simple and effective dietary intervention aimed at maintaining cognitive and retinal function in later life. This will be the first trial of its kind aiming to slow the decline of cognitive and retinal function in older people by increasing daily dietary intake of n-3 LCPs. The link between cognitive ability, visual function and quality of life among older people suggests that this novel line of research may have considerable public health importance.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

    Study of the synergistic effect of 2-methoxy-4-formylphenol and sodium molybdenum oxide on the corrosion inhibition of 3CR12 ferritic steel in dilute sulphuric acid

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    The synergistic effect of the corrosion inhibition properties of 2-methoxy-4-formylphenol and sodium molybdenum oxide on the electrochemical property of 3CR12 ferritic stainless steel in 2M H2SO4 acid solution was assessed through coupon analysis, potentiodynamic polarization technique, IR spectroscopy and micro-analytical technique. Experimental data showed the combined admixture effectively inhibited the steel corrosion at the concentrations analyzed with a maximum inhibition efficiency of 94.47% and 89.71% from coupon analysis and potentiodynamic polarization due to the electrochemical action and inhibition of the steel by the ionized molecules of the inhibiting compound which influenced the mechanism of the redox reactions responsible to corrosion and surface deterioration. Results from corrosion thermodynamic calculations showed chemisorption adsorption mechanism. Infrared spectroscopic images exposed the functional groups of the molecules involved for the corrosion inhibition reaction. Micro-analytical images showed sharp contrast in surface morphology between the inhibited and corroded test specimens under study. Cracks, intergranular and pitting corrosion in addition to severe surface deterioration was observed in the uninhibited samples. Inhibitor adsorption fits the Langmuir isotherm mode
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