20,524 research outputs found
Psychodynamic therapy: a poorly defined concept with questionable evidence
R34 MH086668 - NIMH NIH HHS; R01 AT007257 - NCCIH NIH HHS; R21 MH101567 - NIMH NIH HHS; R34 MH099311 - NIMH NIH HHS; R21 MH102646 - NIMH NIH HHS; K23 MH100259 - NIMH NIH HHS; R01 MH099021 - NIMH NIH HH
New procedure for design of self-adaptive control systems
Adaptive control system compensates for changes in the dynamic characteristics of linear controlled elements. It is mechanized so that the actual input of each control approaches the ideal input
The probability that and commute in a compact group
We show that a compact group has finite conjugacy classes, i.e., is an
FC-group if and only if its center is open if and only if its commutator
subgroup is finite. Let denote the Haar measure of the set of all
pairs in for which ; this, formally, is the
probability that two randomly picked elements commute. We prove that is
always rational and that it is positive if and only if is an extension of
an FC-group by a finite group. This entails that is abelian by finite. The
proofs involve measure theory, transformation groups, Lie theory of arbitrary
compact groups, and representation theory of compact groups. Examples and
references to the history of the discussion are given at the end of the paper.Comment: 17 pages; we have cut some points ; to appear in Math. Proc.
Cambridge Phil. So
Mindfulness-based interventions for anxiety and depression
Published in final edited form as: Psychiatr Clin North Am. 2017 December ; 40(4): 739–749. doi:10.1016/j.psc.2017.08.008.This article reviews the ways in which mindfulness practices have contributed to cognitive and behavioral treatments for depression and anxiety. Research on mindfulness-based interventions (MBIs) has increased rapidly in the past decade. The most common include mindfulness-based stress reduction and mindfulness-based cognitive therapy. MBIs are effective in reducing anxiety and depression symptom severity in a range of individuals. MBIs consistently outperform non-evidence-based treatments and active control conditions, such as health education, relaxation training, and supportive psychotherapy. MBIs also perform comparably with cognitive behavior therapy (CBT). The treatment principles of MBIs for anxiety and depression are compatible with standard CBT.R01 AT007257 - NCCIH NIH HH
Mean first passage time for fission potentials having structure
A schematic model of over-damped motion is presented which permits one to
calculate the mean first passage time for nuclear fission. Its asymptotic value
may exceed considerably the lifetime suggested by Kramers rate formula, which
applies only to very special, favorable potentials and temperatures. The
additional time obtained in the more general case is seen to allow for a
considerable increment in the emission of light particles.Comment: 7 pages, LaTex, 7 postscript figures; Keywords: Decay rate, mean
first passage tim
Investigation of nonlinear motion simulator washout schemes
An overview is presented of some of the promising washout schemes which have been devised. The four schemes presented fall into two basic configurations; crossfeed and crossproduct. Various nonlinear modifications further differentiate the four schemes. One nonlinear scheme is discussed in detail. This washout scheme takes advantage of subliminal motions to speed up simulator cab centering. It exploits so-called perceptual indifference thresholds to center the simulator cab at a faster rate whenever the input to the simulator is below the perceptual indifference level. The effect is to reduce the angular and translational simulation motion by comparison with that for the linear washout case. Finally, the conclusions and implications for further research in the area of nonlinear washout filters are presented
Complex joint probabilities as expressions of determinism in quantum mechanics
The density operator of a quantum state can be represented as a complex joint
probability of any two observables whose eigenstates have non-zero mutual
overlap. Transformations to a new basis set are then expressed in terms of
complex conditional probabilities that describe the fundamental relation
between precise statements about the three different observables. Since such
transformations merely change the representation of the quantum state, these
conditional probabilities provide a state-independent definition of the
deterministic relation between the outcomes of different quantum measurements.
In this paper, it is shown how classical reality emerges as an approximation to
the fundamental laws of quantum determinism expressed by complex conditional
probabilities. The quantum mechanical origin of phase spaces and trajectories
is identified and implications for the interpretation of quantum measurements
are considered. It is argued that the transformation laws of quantum
determinism provide a fundamental description of the measurement dependence of
empirical reality.Comment: 12 pages, including 1 figure, updated introduction includes
references to the historical background of complex joint probabilities and to
related work by Lars M. Johanse
Vigorous atmospheric motion in the red supergiant star Antares
Red supergiant stars represent a late stage of the evolution of stars more
massive than about nine solar masses, in which they develop complex,
multi-component atmospheres. Bright spots have been detected in the atmosphere
of red supergiants using interferometric imaging. Above the photosphere of a
red supergiant, the molecular outer atmosphere extends up to about two stellar
radii. Furthermore, the hot chromosphere (5,000 to 8,000 kelvin) and cool gas
(less than 3,500 kelvin) of a red supergiant coexist at about three stellar
radii. The dynamics of such complex atmospheres has been probed by ultraviolet
and optical spectroscopy. The most direct approach, however, is to measure the
velocity of gas at each position over the image of stars as in observations of
the Sun. Here we report the mapping of the velocity field over the surface and
atmosphere of the nearby red supergiant Antares. The two-dimensional velocity
field map obtained from our near-infrared spectro-interferometric imaging
reveals vigorous upwelling and downdrafting motions of several huge gas clumps
at velocities ranging from about -20 to +20 kilometres per second in the
atmosphere, which extends out to about 1.7 stellar radii. Convection alone
cannot explain the observed turbulent motions and atmospheric extension,
suggesting that an unidentified process is operating in the extended
atmosphere.Comment: 27 pages, 8 figures, published in Natur
Quantum-state tomography for spin-l systems
We show that the density matrix of a spin-l system can be described entirely
in terms of the measurement statistics of projective spin measurements along a
minimum of 4l+1 different spin directions. It is thus possible to represent the
complete quantum statistics of any N-level system within the spherically
symmetric three dimensional space defined by the spin vector. An explicit
method for reconstructing the density matrix of a spin-1 system from the
measurement statistics of five non-orthogonal spin directions is presented and
the generalization to spin-l systems is discussed.Comment: 10 pages, including 2 tables, minor modifications in section II,
final version for publication in Phys. Rev.
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