383 research outputs found
Within-person structures of daily cognitive performance cannot be inferred from between-person structures of cognitive abilities
First published online: 09 June 2020Over a century of research on between-person differences has resulted in the consensus that human cognitive abilities are hierarchically organized, with a general factor, termed general intelligence or "g," uppermost. Surprisingly, it is unknown whether this body of evidence is informative about how cognition is structured within individuals. Using data from 101 young adults performing nine cognitive tasks on 100 occasions distributed over six months, we find that the structures of individuals' cognitive abilities vary among each other, and deviate greatly from the modal between-person structure. Working memory contributes the largest share of common variance to both between- and within-person structures, but the g factor is much less prominent within than between persons. We conclude that between-person structures of cognitive abilities cannot serve as a surrogate for within-person structures. To reveal the development and organization of human intelligence, individuals need to be studied over time
Search for three alpha states around an O core in Si
We investigate the existence of weakly coupled gas-like states comprised of
three particles around an O core in Si. We calculate the
excited states in Si using the multi-configuration mixing method based
on the O + 3 cluster model. We also include the O +
C and Mg + basis wave functions prepared by the
generator coordinate method. To identify the gas-like states, we calculate the
isoscalar monopole transition strengths and the overlap of the obtained states
with the geometrical cluster wave function and the
Tohsaki-Horiuchi-Schuck-R\"{o}pke (THSR) wave function. The results show that
the obtained fourth and twelfth states significantly overlap with the THSR wave
function. These two states clearly coexist with the O + C cluster
states, emerging at similar energies. The calculated isoscalar monopole
strengths between those two states are significantly large, indicating that the
states are members of the excitation mode. Furthermore, the calculated
root-mean-squared (RMS) radii for these states also suggest that a layer of
gas-like three particles could exist around the surface of the
O core, which can be described as a "two-dimensional gas" in the
intermediate state before the Hoyle-like three states emerge.Comment: 5 pages, 3 figure
Alpha-cluster Condensations in Nuclei and Experimental Approaches for their Studies
The formation of alpha-clusters in nuclei close to the decay thresholds is
discussed. These states can be considered to be boson-condensates, which are
formed in a second order phase transition in a mixture of nucleons and
alpha-particles. The de Broglie wavelength of the alpha-particles is larger
than the nuclear diameter, therefore the coherent properties of the
alpha-particles give particular effects for the study of such states. The
states are above the thresholds thus the enhanced emission of multiple-alphas
into the same direction is observed. The probability for the emission of
multiple-alphas is not described by Hauser-Feshbach theory for compound nucleus
decay.Comment: 21 pages, 12 figures
Déjà vu and the entorhinal cortex: dissociating recollective from familiarity disruptions in a single case patient
Past research has demonstrated a relationship between déjà vu and the entorhinal cortex in patients with wider medial temporal lobe damage. The aim of the present research was to investigate this crucial link in a patient (MR) with a selective lesion to the left lateral entorhinal cortex to provide a more direct exploration of this relationship. Two experiments investigated the experiences of déjà vécu (using the IDEA questionnaire) and déjà vu (using an adapted DRM paradigm) in MR and a set of matched controls. The results demonstrated that MR had quantitatively more and qualitatively richer recollective experiences of déjà vécu. In addition, under laboratory-based déjà vu conditions designed to elicit both false recollection (critical lures) and false familiarity (weakly-associated lures), MR only revealed greater memory impairments for the latter. The present results are therefore the first to demonstrate a direct relationship between the entorhinal cortex and the experience of both déjà vu and déjà vécu. They furthermore suggest that the entorhinal cortex is involved in both weakly-associative false memory as well as strongly-associative memory under conditions that promote familiarity-based processing
Di-neutron elastic transfer in the 4He(6He,6He)4He reaction
Elastic He+He data measured at 15.9, and 60.3
MeV have been analyzed within the coupled reaction channels (CRC) formalism,
with the elastic-scattering and two-neutron () transfer amplitudes
coherently included. Contributions from the direct (one-step) and sequential
(two-step) -transfers were treated explicitly based on a realistic
assumption for the -transfer form factor. The oscillatory pattern observed
in He(He,He)He angular distribution at low energies was found
to be due to an interference between the elastic scattering and -transfer
amplitudes. Our CRC analysis shows consistently that the direct -transfer
strongly dominates over the sequential transfer and thus confirms the dominance
of 2He configuration over the He one in the He wave function.
This result suggests a strong clusterization of the two valence neutrons and
allows, therefore, a reliable estimate for the \emph{di-neutron} spectroscopic
amplitude.Comment: Accepted for publication in Phys. Lett.
nature of the superdeformed band of and the evolution of the molecular structure
The relation between the superdeformed band of and molecular bands is studied by the deformed-base
antisymmetrized molecular dynamics with the Gogny D1S force. It is found that
the obtained superdeformed band members of have considerable
amount of the component. Above the superdeformed
band, we have obtained two excited rotational bands which have more prominent
character of the molecular band. These three
rotational bands are regarded as a series of
molecular bands which were predicted by using the unique
- optical potentil. As the excitation energy and principal
quantum number of the relative motion increase, the cluster structure becomes more prominent but at the same time, the band
members are fragmented into several states
- …