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A physiological marker of recognition memory in adults with autism spectrum disorder? The Pupil Old/New Effect
This study investigated the pupil Old/New effect in individuals with Autism Spectrum Disorder (ASD) and typical development (TD). Participants studied verbal and visual meaningful and meaningless materials in black and white on a computer screen. Pupil sizes were measured while participants performed a Remember (episodic memory with context) /Know (semantic memory, no context) recognition memory test. ASD compared to TD individuals showed significantly reduced recognition rates for all materials. Both groups showed better memory for visual compared to verbal (picture superiority effect) and meaningful compared to meaningless materials. A pupil size ratio (pupil size for test item divided by baseline) for old (studied) and new (unstudied) materials indicated larger pupils for old compared to new materials only for the TD but not the ASD group. Pupil size in response to old versus new items was positively related to recognition accuracy, confirming that the pupil Old/New effect reflects a memory phenomenon in the ASD group. In addition, this study suggests an involvement of the noradrenergic neurotransmitter system in the abnormal hippocampal functioning in ASD. Implications of these findings as well as their underlying neurophysiology will be discussed in relation to current theories of memory in ASD
Relativistic description of nuclear matrix elements in neutrinoless double- decay
Neutrinoless double- () decay is related to many
fundamental concepts in nuclear and particle physics beyond the standard model.
Currently there are many experiments searching for this weak process. An
accurate knowledge of the nuclear matrix element for the decay
is essential for determining the effective neutrino mass once this process is
eventually measured. We report the first full relativistic description of the
decay matrix element based on a state-of-the-art nuclear
structure model. We adopt the full relativistic transition operators which are
derived with the charge-changing nucleonic currents composed of the vector
coupling, axial-vector coupling, pseudoscalar coupling, and weak-magnetism
coupling terms. The wave functions for the initial and final nuclei are
determined by the multireference covariant density functional theory (MR-CDFT)
based on the point-coupling functional PC-PK1. The low-energy spectra and
electric quadrupole transitions in Nd and its daughter nucleus
Sm are well reproduced by the MR-CDFT calculations. The
decay matrix elements for both the
and decays of Nd are evaluated. The effects
of particle number projection, static and dynamic deformations, and the full
relativistic structure of the transition operators on the matrix elements are
studied in detail. The resulting decay matrix element for the
transition is , which gives the most optimistic
prediction for the next generation of experiments searching for the
decay in Nd.Comment: 17 pages, 9 figures; table adde
Covariant density functional theory: The role of the pion
We investigate the role of the pion in Covariant Density Functional Theory.
Starting from conventional Relativistic Mean Field (RMF) theory with a
non-linear coupling of the -meson and without exchange terms we add
pions with a pseudo-vector coupling to the nucleons in relativistic
Hartree-Fock approximation. In order to take into account the change of the
pion field in the nuclear medium the effective coupling constant of the pion is
treated as a free parameter. It is found that the inclusion of the pion to this
sort of density functionals does not destroy the overall description of the
bulk properties by RMF. On the other hand, the non-central contribution of the
pion (tensor coupling) does have effects on single particle energies and on
binding energies of certain nuclei.Comment: 12 pages, 5 figure
Systematic study of nuclear matrix elements in neutrinoless double-beta decay with a beyond mean-field covariant density functional theory
We report a systematic study of nuclear matrix elements (NMEs) in
neutrinoless double-beta decays with a state-of-the-art beyond mean-field
covariant density functional theory. The dynamic effects of particle-number and
angular-momentum conservations as well as quadrupole shape fluctuations are
taken into account with projections and generator coordinate method for both
initial and final nuclei. The full relativistic transition operator is adopted
to calculate the NMEs. The present systematic studies show that in most of the
cases there is a much better agreement with the previous non-relativistic
calculation based on the Gogny force than in the case of the nucleus Nd
found in Song et al. [Phys. Rev. C 90, 054309 (2014)]. In particular, we find
that the total NMEs can be well approximated by the pure axial-vector coupling
term with a considerable reduction of the computational effort.Comment: 9 pages with 7 figures and 3 table
Spectroscopy of the heaviest nuclei (theory)
Recent progress in the applications of covariant density functional theory
(CDFT) to the description of the spectroscopy of the heaviest nuclei is
reviewed. The analysis of quasiparticle spectra in actinides and the heaviest A
~ 250 nuclei provides a measure of the accuracy of the description of
single-particle energies in CDFT and an additional constraint for the choice of
effective interactions for the description of superheavy nuclei. The response
of these nuclei to the rotation is rather well described by cranked
relativistic Hartree+Bogoliubov theory and it serves as a supplementary tool in
configuration assignment in odd-mass nuclei. A systematic analysis of the
fission barriers with allowance for triaxial deformation shows that covariant
density functional theory is able to describe fission barriers on a level of
accuracy comparable with the best phenomenological macroscopic+microscopic
approaches.Comment: 10 pages, 7 figures, invited talk of A.V. Afanasjev at the
International Nuclear Physics Conference (INPC 2010), Vancouver, Canada, July
4-9, 2010, to be published in Journal of Physics G: Conference Series (JPCS
Extrapolation method in shell model calculations with deformed basis
An extrapolation method in shell model calculations with deformed basis is
presented, which uses a scaling property of energy and energy variance for a
series of systematically approximated wave functions to the true one. Such
approximated wave functions are given by variation-after-projection method
concerning the full angular momentum projection. This extrapolation needs
energy variance, which amounts to the calculation of expectation value of
square of Hamiltonian . We present the method to evaluate this
matrix element and show that large reduction of its numerical computation can
be done by taking an advantage of time-reversal symmetry. The numerical tests
are presented for shell calculations with a realistic residual
interaction.Comment: 5 pages, 2 figures, accepted for publication in Phys. Rev.
Further explorations of Skyrme-Hartree-Fock-Bogoliubov mass formulas. III: Role of particle-number projection
Starting from HFB-6, we have constructed a new mass table, referred to as
HFB-8, including all the 9200 nuclei lying between the two drip lines over the
range of Z and N > 6 and Z < 122. It differs from HFB-6 in that the wave
function is projected on the exact particle number. Like HFB-6, the isoscalar
effective mass is constrained to the value 0.80 M and the pairing is density
independent. The rms errors of the mass-data fit is 0.635 MeV, i.e. better than
almost all our previous HFB mass formulas. The extrapolations of this new mass
formula out to the drip lines do not differ significantly from the previous
HFB-6 mass formula.Comment: 9 pages, 7 figures, accepted for publication in Phys. Rev.
Extended RPA with ground-state correlations in a solvable model
The ground states and excited states of the Lipkin model hamiltonian are
calculated using a new theoretical approach which has been derived from an
extended time-dependent Hartree-Fock theory known as the time-dependent
density-matrix theory (TDDM). TDDM enables us to calculate correlated ground
states, and its small amplitude limit (STDDM), which is a version of extended
RPA theories based on a correlated ground state, can be used to calculate
excited states. It is found that this TDDM plus STDDM approach gives much
better results for both the ground states and the excited states than the
Hartree-Fock ground state plus RPA approach.Comment: 4 pages, 4 figure
Effects of personal and situational factors on self-referenced doping likelihood
Objectives
The present study examined the role of moral identity, self-regulatory efficacy and moral disengagement on athletes' doping likelihood in situations representing potential benefits and costs for themselves.
Design
Using a cross-sectional design, doping likelihood was assessed indirectly via hypothetical scenarios.
Method
Athletes (N = 262) indicated their likelihood of doping in hypothetical situations and completed measures of moral identity, doping self-regulatory efficacy, and doping moral disengagement.
Results
Doping was more likely in benefit situations than in cost situations. Doping likelihood was negatively correlated moral identity, negatively correlated with self-regulatory efficacy, and positively correlated with moral disengagement in both situations. The coefficients were higher for moral identity in cost situations, self-regulatory efficacy in benefit situations, and moral disengagement in benefit situations. Process analyses indicated that moral identity was directly related to doping likelihood only in cost situations and indirectly related to doping likelihood via increased self-regulatory efficacy only in benefit situations. Moral identity was indirectly related to doping likelihood via decreased moral disengagement and via increased self-regulatory efficacy and decreased moral disengagement in both situations.
Conclusions
By showing that doping likelihood is associated with personal and situational factors our findings provide support for a social cognitive model of doping based on Bandura’s theory of moral thought and action and Aquino’s theory of moral identity
Development of a carbon dioxide-water solid oxide electrolyte electrolysis system Annual report, 29 Mar. 1968 - 29 May 1969
Carbon dioxide-water solid oxide electrolyte electrolysis syste
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