20,356 research outputs found
The Availability of Training Opportunities in Personality Disorders in American Psychological Association- and Psychological Clinical Science Accreditation System-Accredited Clinical and Counseling Psychology Doctoral Programs
Personality disorders are relatively common, especially in clinical settings. A number of evidence-based treatments are now available, especially for borderline personality disorder. However, little is known about the relevant training available to doctoral students in clinical and counseling psychology. in the current study, data were extracted from 336 clinical and counseling Ph.D. and Psy.D. programs from the Insider’s Guide to Graduate Programs in Clinical and Counseling Psychology (Norcross & Sayette, 2020), including the number of programs with faculty with specific interests in personality disorders and the number of programs with clinical opportunities related to personality disorders. We found that formal training in personality disorders is not widely available to most trainees in APA-accredited doctoral training programs. Only 16% of programs have faculty with interests in personality disorders, all of them clinical psychology programs. Ph.D. programs were more likely to have PD-interested faculty than Psy.D. programs, and, within clinical Ph.D. programs, PCSAS-accredited programs were more likely to have PD-interested faculty than programs without PCSAS accreditation. Similarly, only 15% of programs (all clinical psychology programs) offer practicum opportunities in psychotherapy for personality disorders. Our findings indicate that doctoral level psychology programs are not sufficiently preparing their students with personality disorder training, which serves as a substantial disservice to both trainees and the public
Thermodynamics as an alternative foundation for zero-temperature density functional theory and spin density functional theory
Thermodynamics provides a transparent definition of the free energy of
density functional theory (DFT), and of its derivatives - the potentials, at
finite temperatures T. By taking the T to 0 limit, it is shown here that both
DFT and spin-dependent DFT (for ground states) suffer from precisely the same
benign ambiguities: (a) charge and spin quantization lead to "up to a constant"
indeterminacies in the potential and the magnetic field respectively, and (b)
the potential in empty subspaces is undetermined but irrelevant. Surprisingly,
these simple facts were inaccessible within the standard formulation, leading
to recent discussions of apparent difficulties within spin-DFT.Comment: RevTeX, to appear in Phys. Rev.
Center of mass and relative motion in time dependent density functional theory
It is shown that the exchange-correlation part of the action functional
in time-dependent density functional theory , where
is the time-dependent density, is invariant under the
transformation to an accelerated frame of reference , where is an arbitrary
function of time. This invariance implies that the exchange-correlation
potential in the Kohn-Sham equation transforms in the following manner:
. Some of the
approximate formulas that have been proposed for satisfy this exact
transformation property, others do not. Those which transform in the correct
manner automatically satisfy the ``harmonic potential theorem", i.e. the
separation of the center of mass motion for a system of interacting particles
in the presence of a harmonic external potential. A general method to generate
functionals which possess the correct symmetry is proposed
Volatility clustering and scaling for financial time series due to attractor bubbling
A microscopic model of financial markets is considered, consisting of many
interacting agents (spins) with global coupling and discrete-time thermal bath
dynamics, similar to random Ising systems. The interactions between agents
change randomly in time. In the thermodynamic limit the obtained time series of
price returns show chaotic bursts resulting from the emergence of attractor
bubbling or on-off intermittency, resembling the empirical financial time
series with volatility clustering. For a proper choice of the model parameters
the probability distributions of returns exhibit power-law tails with scaling
exponents close to the empirical ones.Comment: For related publications see http://www.helbing.or
Local Ferroelectricity in SrTiO_3 Thin Films
The temperature-dependent polarization of SrTiO_3 thin films is investigated
using confocal scanning optical microscopy. A homogeneous out-of-plane and
inhomogeneous in-plane ferroelectric phase are identified from images of the
linear electrooptic response. Both hysteretic and non-hysteretic behavior are
observed under a dc bias field. Unlike classical transitions in bulk
ferroelectrics, local ferroelectricity is observed at temperatures far above
the dielectric permittivity maximum. The results demonstrate the utility of
local probe experiments in understanding inhomogeneous ferroelectrics.Comment: 8 pages, 3 figures, accepted for publication in PR
Ultrasound Investigations of Orbital Quadrupolar Ordering in UPd_3
For a high-quality single crystal of UPd_3 we present the relevant elastic
constants and ultrasonic attenuation data. In addition to the magnetic phase
transition at T_2=4.4 +/- 0.1K and the quadrupolar transition at T_1~6.8K, we
find orbital ordering at T_0=7.6 +/- 0.1K concomitant with a symmetry change
from hexagonal to orthorhombic. A striking feature is the splitting of the
phase transition at T_1 into a second-order transition at T_{+1}=6.9 +/- 0.05K
and a first-order transition at T_{-1}=6.7 +/- 0.05K. For the four phase
transitions, the quadrupolar order parameters and the respective symmetry
changes are specified.Comment: 14 pages (RevTex), 3 eps-figures, accepted by PR
Exploring Foundations of Time-Independent Density Functional Theory for Excited-States
Based on the work of Gorling and that of Levy and Nagy, density-functional
formalism for many Fermionic excited-states is explored through a careful and
rigorous analysis of the excited-state density to external potential mapping.
It is shown that the knowledge of the ground-state density is a must to fix the
mapping from an excited-state density to the external potential. This is the
excited-state counterpart of the Hohenberg-Kohn theorem, where instead of the
ground-state density the density of the excited-state gives the true many-body
wavefunctions of the system. Further, the excited-state Kohn-Sham system is
defined by comparing it's non-interacting kinetic energy with the true kinetic
energy. The theory is demonstrated by studying a large number of atomic
systems.Comment: submitted to J. Chem. Phy
On-chip non-reciprocal optical devices based on quantum inspired photonic lattices
We propose a novel geometry for integrated photonic devices that can be used
as isolators and polarization splitters based on engineered photonic lattices.
Starting from optical waveguide arrays that mimic Fock space representation of
a non-interacting two-site Bose Hubbard Hamiltonian, we show that introducing
magneto-optic nonreciprocity to these structures leads to a superior optical
isolation performance. In the forward propagation direction, an input TM
polarized beam experiences a perfect state transfer between the input and
output waveguide channels while surface Bloch oscillations block the backward
transmission between the same ports. Our analysis indicates a large isolation
ratio of 75 dB after a propagation distance of 8 mm inside seven coupled
waveguides. Moreover, we demonstrate that, a judicious choice of the
nonreciprocity in this same geometry can lead to perfect polarization
splitting.Comment: 13 pages 3 figure
Surface Enhancement of Superconductivity in Tin
The possibility of surface enhancement of superconductivity is examined
experimentally. It is shown that single crystal tin samples with cold-worked
surfaces represent a superconductor with a surface-enhanced order parameter (or
negative surface extrapolation length b), whose magnitude can be controlled.Comment: 8 pages, 4 figure
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