5,665 research outputs found
Some remarks on modified power entropy
The aim of this note is to point out some observations concerning modified
power entropy of - and -actions. First, we provide an elementary
example showing that this quantity is sensitive to transient dynamics, and
therefore does not satisfy a variational principle. Further, we show that
modified power entropy is not suitable to detect the break of equicontinuity
which takes place during the transition from almost periodic to almost
automorphic minimal systems. In this respect, it differs from power entropy and
amorphic complexity, which are two further topological invariants for zero
entropy systems (`slow entropies'). Finally, we construct an example of an
irregular Toeplitz flow with zero modified power entropy.Comment: 17 pages, to appear in AMS Contemporary Mathematics serie
Longitudinally Polarized Photoproduction of Inclusive Hadrons at Fixed-Target Experiments
We present a detailed phenomenological study of spin-dependent
single-inclusive high-p_T hadron photoproduction with particular emphasis on
the kinematics relevant for the Compass and Hermes fixed-target experiments. We
carefully examine the theoretical uncertainties associated with the only
moderate transverse momenta accessible in such measurements and analyze the
sensitivity of the relevant spin asymmetries to the gluon polarization in the
nucleon as well as to the completely unknown parton content of circularly
polarized photons.Comment: 12 pages, 14 figures; final version to appear in EPJC; comparison to
E155 data and references adde
Non-equilibrium condensation and coarsening of field-driven dipolar colloids
In colloidal suspensions, self-organization processes can be easily fueled by
external fields. One particularly interesting class of phenomena occurs in
monolayers of dipolar particles that are driven by rotating external fields.
Here we report results from a computer simulation study of such systems
focusing on the clustering behavior also observed in recent experiments. The
key result of this paper is a novel interpretation of this pattern formation
phenomenon: We show the clustering to be a by-product of a vapor-liquid first
order phase transition. In fact, the observed dynamic coarsening process
corresponds to the spindodal demixing that occurs during such a transitionComment: 6 pages, 5 figure
Modeling charge transport in C60-based self-assembled monolayers for applications in field-effect transistors
We have investigated the conductance properties of C60-containing
self-assembled monolayers (SAMs), which are used in organic field-effect
transistors, employing a combination of molecular-dynamics simulations,
semiempirical electronic structure calculations and Landauer transport theory.
The results reveal the close relation between the transport characteristics and
the structural and electronic properties of the SAM. Furthermore, both local
pathways of charge transport in the SAMs and the influence of structural
fluctuations are analyzed.Comment: 10 figure
The Shape of Covariantly Smeared Sources in Lattice QCD
Covariantly smeared sources are commonly used in lattice QCD to enhance the
projection onto the ground state. Here we investigate the dependence of their
shape on the gauge field background and find that the presence of localized
concentrations of magnetic field can lead to strong distortions which reduce
the smearing radii achievable by iterative smearing prescriptions. In
particular, as , iterative procedures like Jacobi smearing require
increasingly large iteration counts in order to reach physically-sized smearing
radii 0.5 fm, and the resulting sources are strongly distorted. To
bypass this issue, we propose a covariant smearing procedure (``free-form
smearing'') that allows us to create arbitrarily shaped sources, including in
particular Gaussians of arbitrary radius.Comment: 1+15 pages, 7 figures (24 pdf images
Psychiatrische Versorgungsepidemiologie
Zusammenfassung: Psychiatrische Versorgungsepidemiologie untersucht die Situation der Versorgung von Menschen mit psychischen Erkrankungen unter Alltagsbedingungen. Psychiatrische Versorgungsstrukturen in Deutschland haben sich in den letzten Jahrzehnten weg von stationärer Behandlung mit teilweise mehrmonatiger Aufenthaltsdauer hin zu dezentralen teilstationären und ambulanten Angeboten entwickelt. Derzeit hat sich die Verschiebung von Behandlungskapazitäten zwischen den Settings stabilisiert und der Schwerpunkt der Versorgungsplanung liegt mehr auf der Entwicklung von möglichst flächendeckenden Strukturen zur Vernetzung der oftmals noch fragmentierten und streng an den Sektorgrenzen orientierten Versorgungslandschaft. Der Versorgungsbedarf hängt mit einer Vielzahl Faktoren wie den epidemiologischen Daten der Bevölkerung, der Inanspruchnahme und den gesundheitspolitischen Rahmenbedingungen zusammen. Ob die derzeitigen Versorgungsstrukturen den aktuellen Bedarf abdecken und den Qualitätsansprüchen genügen, ist aufgrund der spärlichen Datenlage und dem Mangel an Referenzmaßstäben nur schwer zu beurteilen. Ein substanzieller Ausbau psychiatrischer Versorgungsforschung in den kommenden Jahren ist hierfür grundlegend erforderlic
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