496 research outputs found
Patienten mit schizophrenen Störungen im psychiatrischen Maßregelvollzug: Ergeben sich Konsequenzen für die Allgemeinpsychiatrie?
Zusammenfassung: Es wurde eine Erhebung zu soziodemographischen, kriminologischen und psychiatrischen Merkmalen der 2007 gemäß §63 StGB und §126a StPO in Mecklenburg-Vorpommern untergebrachten Patienten mit Erkrankungen aus dem schizophrenen Formenkreis durchgeführt. Dabei konnten Daten zu allen im Untersuchungszeitraum untergebrachten 45Probanden erhoben werden. Diese stellen einen Anteil von 22% an der Gesamtzahl der 202 im Erhebungszeitraum untergebrachten Patienten. Dieser Wert liegt deutlich unter den Daten westlicher und auch eher städtisch geprägter Bundesländer. Ähnlich wie in anderen Untersuchungen aus Deutschland und Österreich zeigt sich eine hohe Rate von Vorbehandlungen in der Allgemeinpsychiatrie. Es bleibt eine wichtige Aufgabe, adäquate Interventionsstrategien für fremdaggressive Patienten mit kombinierten psychischen Störungen (z.B. Schizophrenie und Sucht), strafrechtlicher Vorgeschichte und fehlenden sozialen Perspektiven zu entwickel
Raman study of carrier-overdoping effects on the gap in high-Tc superconducting cuprates
Raman scattering in the heavily overdoped (Y,Ca)Ba_2Cu_3O_{7-d} (T_c = 65 K)
and Bi_2Sr_2CaCu_2O_{8+d} (T_c = 55 K) crystals has been investigated. For the
both crystals, the electronic pair-breaking peaks in the A_{1g} and B_{1g}
polarizations were largely shifted to the low energies close to a half of
2Delta_0, Delta_0 being the maximum gap. It strongly suggests s-wave mixing
into the d-wave superconducting order parameter and the consequent
manifestation of the Coulomb screening effect in the B_{1g}-channel. Gradual
mixing of s-wave component with overdoping is not due to the change of crystal
structure symmetry but a generic feature in all high-T_c superconducting
cuprates.Comment: 5 pages, 4 figures, to be published in Phys. Rev. B, Rapid
communicaito
Anomalous Self-Energy Effects of the B_1g Phonon in Y_{1-x}(Pr,Ca)_xBa_2Cu_3O_7 Films
In Raman spectra of cuprate superconductors the gap shows up both directly,
via a redistribution of the electronic background, the so-called "2Delta
peaks", and indirectly, e.g. via the renormalization of phononic excitations.
We use a model that allows us to study the redistribution and the related
phonon self-energy effects simultaneously. We apply this model to the B_1g
phonon of Y_{1-x}(Pr,Ca)_xBa_2Cu_3O_7 films, where Pr or Ca substitution
enables us to investigate under- and overdoped samples. While various
self-energy effects can be explained by the strength and energy of the 2\Delta
peaks, anomalies remain. We discuss possible origins of these anomalies.Comment: 6 pages including 4 figure
Host Plant Use by Competing Acacia-Ants: Mutualists Monopolize While Parasites Share Hosts
Protective ant-plant mutualisms that are exploited by non-defending parasitic ants represent prominent model systems for ecology and evolutionary biology. The mutualist Pseudomyrmex ferrugineus is an obligate plant-ant and fully depends on acacias for nesting space and food. The parasite Pseudomyrmex gracilis facultatively nests on acacias and uses host-derived food rewards but also external food sources. Integrative analyses of genetic microsatellite data, cuticular hydrocarbons and behavioral assays showed that an individual acacia might be inhabited by the workers of several P. gracilis queens, whereas one P. ferrugineus colony monopolizes one or more host trees. Despite these differences in social organization, neither of the species exhibited aggressive behavior among conspecific workers sharing a tree regardless of their relatedness. This lack of aggression corresponds to the high similarity of cuticular hydrocarbon profiles among ants living on the same tree. Host sharing by unrelated colonies, or the presence of several queens in a single colony are discussed as strategies by which parasite colonies could achieve the observed social organization. We argue that in ecological terms, the non-aggressive behavior of non-sibling P. gracilis workers — regardless of the route to achieve this social structure — enables this species to efficiently occupy and exploit a host plant. By contrast, single large and long-lived colonies of the mutualist P. ferrugineus monopolize individual host plants and defend them aggressively against invaders from other trees. Our findings highlight the necessity for using several methods in combination to fully understand how differing life history strategies affect social organization in ants
Phonon Hall effect in ionic crystals in the presence of static magnetic field
We study phonon Hall effect (PHE) for ionic crystals in the presence of
static magnetic field. Using Green-Kubo formula, we present an exact
calculation of thermal conductivity tensor by considering both positive and
negative frequency phonons. Numerical results are shown for some lattices such
as hexagonal lattices, triangular lattices, and square lattices. We find that
the PHE occurs on the nonmagnetic ionic crystal NaCl, although the magnitude is
very small which is due to the tiny charge-to-mass ratio of the ions. The
off-diagonal thermal conductivity is finite for nonzero magnetic field and
changes sign for high value of magnetic field at high temperature. We also
found that the off-diagonal thermal conductivity diverges as at low
temperature
Women’s agency in living apart together: constraint, strategy and vulnerability
Recent research suggests that women can use living apart together (LAT) for a
reflexive and strategic undoing of the gendered norms of cohabitation. In this article
we examine this assertion empirically, using a representative survey from Britain in
2011 and follow-up interviews. First, we find little gender differentiation in practices,
expectations, or attitudes about LAT, or reasons for LAT. This does not fit in with
ideas of undoing gender. Secondly, in examining how women talk about LAT in
relation to gender, we distinguish three groups of ‘constrained’, ‘strategic’ and
‘vulnerable’ female interviewees. All valued the extra space and time that LAT
could bring, many welcomed some release from traditional divisions of labour, and
some were glad to escape unpleasant situations created by partnership with men.
However, for the constrained and vulnerable groups LAT was second best, and any
relaxation of gendered norms was seen as incidental and inconsequential to their
major aim, or ideal, of the ‘proper family’ with cohabitation and marriage. Rather,
their agency in achieving this was limited by more powerful agents, or was a reaction
to perceived vulnerability. While the strategic group showed more purposeful
behaviour in avoiding male authority, agency remained relational and bonded.
Overall we find that women, at least in Britain, seldom use LAT to purposefully or
reflexively undo gender. Equally, LAT sometimes involves a reaffirmation of
gendered norms. LAT is a multi-faceted adaption to circumstances where new
autonomies can at the same time incorporate old subordinations, and new arrangements
can herald conventional family forms
Electronic Raman scattering in YBCO and other superconducting cuprates
Superconductivity induced structures in the electronic Raman spectra of
high-Tc superconductors are computed using the results of ab initio LDA-LMTO
three-dimensional band structure calculations via numerical integrations of the
mass fluctuations, either in the whole 3D Brillouin zone or limiting the
integrations to the Fermi surface. The results of both calculations are rather
similar, the Brillouin zone integration yielding additional weak structures
related to the extended van Hove singularities. Similar calculations have been
performed for the normal state of these high-Tc cuprates. Polarization
configurations have been investigated and the results have been compared to
experimental spectra. The assumption of a simple d_(x^2-y^2)-like gap function
allows us to explain a number of experimental features but is hard to reconcile
with the relative positions of the A1g and B1g peaks.Comment: 14 pages, LaTeX (RevTeX), 5 PostScript figures, uses multicol.sty,
submitted to PR
High resolution 3D imaging of living cells with sub-optical wavelength phonons
Label-free imaging of living cells below the optical diffraction limit poses great challenges for optical microscopy. Biologically relevant structural information remains below the Rayleigh limit and beyond the reach of conventional microscopes. Super-resolution techniques are typically based on the nonlinear and stochastic response of fluorescent labels which can be toxic and interfere with cell function. In this paper we present, for the first time, imaging of live cells using sub-optical wavelength phonons. The axial imaging resolution of our system is determined by the acoustic wavelength (λa = λprobe/2n) and not on the NA of the optics allowing sub-optical wavelength acoustic sectioning of samples using the time of flight. The transverse resolution is currently limited to the optical spot size. The contrast mechanism is significantly determined by the mechanical properties of the cells and requires no additional contrast agent, stain or label to image the cell structure. The ability to breach the optical diffraction limit to image living cells acoustically promises to bring a new suite of imaging technologies to bear in answering exigent questions in cell biology and biomedicine
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