816 research outputs found
Communicating Mental Illness in the Black American Community
Human-human interactions are of central relevance for the success in professional and occupational environments, which also substantially influence quality of life. This is especially true in the case of individuals with high-functioning autism (HFA), who experience deficits in social cognition that often lead to social exclusion and unemployment. Despite good education and high motivation, individuals with HFA do not reach employment rates that are substantially higher than 50 %. This is an alarmingly high rate of unemployment considering that the United Nations have recently emphasized the inclusion of handicapped persons as a mandatory human right. To date, the specific needs of autistic persons with respect to their working environment are largely unexplored. It remains moreover an open question how support systems and activities, including newly developed communication devices for professional environments of individuals with HFA, should look like. The German health and social care systems are not adequately prepared for the proper support of this population. This leads us to suggest that supported employment programs should be developed for adults with HFA that specifically address their needs and requirements. Such programs should comprise (1) the adequate assessment of HFA, including a neuropsychological profile and an individual matching of persons' preferences with requirements of the working place, (2) on-the-job coaching activities that include systematic communication and interaction training, and (3) instruction of non-autistic peers, including colleagues and supervisors, about weaknesses and strengths of HFA
The impact of telecommuting on psychological distress:A cross-lagged study during the COVID-19 pandemic
The impact of telecommuting on psychological distress:A cross-lagged study during the COVID-19 pandemic
Algebraically general, gravito-electric rotating dust
The class of gravito-electric, algebraically general, rotating `silent' dust
space-times is studied. The main invariant properties are deduced. The number
of functionally independent zero-order Riemann invariants satisfies
and special attention is given to the subclass .
Whereas there are no -term limits comprised in the class, the limit
for vanishing vorticity leads to two previously derived irrotational dust
families with , and the shear-free limit is the G\"{o}del universe.Comment: 10 pages, changed to revtex style, extended discussion section, minor
correction
Quasi-Newtonian dust cosmologies
Exact dynamical equations for a generic dust matter source field in a
cosmological context are formulated with respect to a non-comoving
Newtonian-like timelike reference congruence and investigated for internal
consistency. On the basis of a lapse function (the relativistic
acceleration scalar potential) which evolves along the reference congruence
according to (), we find that
consistency of the quasi-Newtonian dynamical equations is not attained at the
first derivative level. We then proceed to show that a self-consistent set can
be obtained by linearising the dynamical equations about a (non-comoving) FLRW
background. In this case, on properly accounting for the first-order momentum
density relating to the non-relativistic peculiar motion of the matter,
additional source terms arise in the evolution and constraint equations
describing small-amplitude energy density fluctuations that do not appear in
similar gravitational instability scenarios in the standard literature.Comment: 25 pages, LaTeX 2.09 (10pt), to appear in Classical and Quantum
Gravity, Vol. 15 (1998
Dynamical systems approach to G2 cosmology
In this paper we present a new approach for studying the dynamics of
spatially inhomogeneous cosmological models with one spatial degree of freedom.
By introducing suitable scale-invariant dependent variables we write the
evolution equations of the Einstein field equations as a system of autonomous
partial differential equations in first-order symmetric hyperbolic format,
whose explicit form depends on the choice of gauge. As a first application, we
show that the asymptotic behaviour near the cosmological initial singularity
can be given a simple geometrical description in terms of the local past
attractor on the boundary of the scale-invariant dynamical state space. The
analysis suggests the name ``asymptotic silence'' to describe the evolution of
the gravitational field near the cosmological initial singularity.Comment: 28 pages, 3 tables, 1 *.eps figure, LaTeX2e (10pt), matches version
accepted for publication by Classical and Quantum Gravit
Frame dragging, vorticity and electromagnetic fields in axially symmetric stationary spacetimes
We present a general study about the relation between the vorticity tensor
and the Poynting vector of the electromagnetic field for axially symmetric
stationary electrovacuum metrics. The obtained expressions allow to understand
the role of the Poynting vector in the dragging of inertial frames. The
particular case of the rotating massive charged magnetic dipole is analyzed in
detail. In addition, the electric and magnetic parts of the Weyl tensor are
calculated and the link between the later and the vorticity is established.
Then we show that, in the vacuum case, the necessary and sufficient condition
for the vanishing of the magnetic part is that the spacetime be static.Comment: 16 pages Latex. Some minor changes in the text and typos correcte
Causal propagation of geometrical fields in relativistic cosmology
We employ the extended 1+3 orthonormal frame formalism for fluid spacetime
geometries , which contains the Bianchi field
equations for the Weyl curvature, to derive a 44-D evolution system of
first-order symmetric hyperbolic form for a set of geometrically defined
dynamical field variables. Describing the matter source fields
phenomenologically in terms of a barotropic perfect fluid, the propagation
velocities (with respect to matter-comoving observers that Fermi-propagate
their spatial reference frames) of disturbances in the matter and the
gravitational field, represented as wavefronts by the characteristic 3-surfaces
of the system, are obtained. In particular, the Weyl curvature is found to
account for two (non-Lorentz-invariant) Coulomb-like characteristic eigenfields
propagating with and four transverse characteristic eigenfields
propagating with , which are well known, and four
(non-Lorentz-invariant) longitudinal characteristic eigenfields propagating
with |v| = \sfrac{1}{2}. The implications of this result are discussed in
some detail and a parallel is drawn to the propagation of irregularities in the
matter distribution. In a worked example, we specialise the equations to
cosmological models in locally rotationally symmetric class II and include the
constraints into the set of causally propagating dynamical variables.Comment: 25 pages, RevTeX (10pt), accepted for publication by Physical Review
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