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The crystal structure and magnetic correlations in triangular antiferromagnet FeGa₂S₄ are studied by x-ray diffraction, magnetic susceptibility, neutron diffraction, and neutron inelastic scattering. We report significant mixing at the cation sites and disentangle magnetic properties dominated by major and minor magnetic sites. The magnetic short-range correlations at 0.77 Å⁻¹ correspond to the major sites and being static at base temperature they evolve into dynamic correlations around 30–50 K. The minor sites contribute to the magnetic peak at 0.6 Å⁻¹, which vanishes at 5.5 K. Our analytical studies of triangular lattice models with bilinear and biquadratic terms provide the ratios between exchanges for the proposed ordering vectors. The modeling of the inelastic neutron spectrum within linear spin-wave theory results in the set of exchange couplings J₁ = 1.7, J₂ = 0.9, J₃ = 0.8 meV for the bilinear Heisenberg Hamiltonian. However, not all features of the excitation spectrum are explained with this model., Instituto de Física de Líquidos y Sistemas Biológicos

Einleitung:Die richtige Dosierung in der Therapie bei der jeweilig herrschenden Wundheilungsphase zu finden, ist eine grosse Herausforderung. Bei grossflächigen, mit Narbensträngen versehenen Verbrennungsflächen, ist ein homogener mechanischer Dehn Reiz fast unmöglich. Der mechanische[zum vollständigen Text gelangen Sie über die oben angegebene URL], 35. Jahrestagung der Deutschsprachigen Arbeitsgemeinschaft für Verbrennungsbehandlung (DAV 2017)

Einleitung: Die richtige Dosierung bei der Mobilisation von Verbrennungsnarben zu finden ist eine große Herausforderung. Bei großflächigen, mit Narbensträngen versehenen Verbrennungsflächen, ist ein homogener mechanischer Dehn Reiz fast unmöglich. Der mechanische Reiz wird[zum vollständigen Text gelangen Sie über die oben angegebene URL], 34. Jahrestagung der Deutschsprachigen Arbeitsgemeinschaft für Verbrennungsbehandlung (DAV 2016)

Einleitung: Diese Case study zeigt einen knapp 30-jährigen Patienten mit einer Verbrennung von 88% der Körperoberfläche. Die Präsentation beinhaltet die stationäre Rehabilitation ca. 10 Monate nach dem Unfallereignis Ziele: Darstellung eines Rehabilitationsverlaufes[zum vollständigen Text gelangen Sie über die oben angegebene URL], 34. Jahrestagung der Deutschsprachigen Arbeitsgemeinschaft für Verbrennungsbehandlung (DAV 2016)

© 2015, NPG. All rights reserved. The recent discovery of pressure (p) induced superconductivity in the binary helimagnet CrAs has raised questions on how superconductivity emerges from the magnetic state and on the mechanism of the superconducting pairing. In the present work the suppression of magnetism and the occurrence of superconductivity in CrAs were studied by means of muon spin rotation. The magnetism remains bulk up to p≃3.5 kbar while its volume fraction gradually decreases with increasing pressure until it vanishes at p≃7 kbar. At 3.5 kbar superconductivity abruptly appears with its maximum Tc≃1.2 K which decreases upon increasing the pressure. In the intermediate pressure region (3.5≲p≲7 kbar) the superconducting and the magnetic volume fractions are spatially phase separated and compete for phase volume. Our results indicate that the less conductive magnetic phase provides additional carriers (doping) to the superconducting parts of the CrAs sample thus leading to an increase of the transition temperature (Tc) and of the superfluid density (ρs). A scaling of ρs with Tc3.2 as well as the phase separation between magnetism and superconductivity point to a conventional mechanism of the Cooper-pairing in CrAs.

BiCu2PO6 is a frustrated two-leg spin-ladder compound with a spin gap that can be closed with a magnetic field of approximately 20 T. This quantum phase transition and its related phase diagram as a function of magnetic field and temperature (H, T) are investigated up to 60 T by means of specific heat, magnetocaloric effect, magnetization, and magnetostriction measurements. In contrast to other gapped quantum magnets, BiCu2PO6 undergoes a series of unexpected first- and second-order phase transitions when an external magnetic field is applied along the crystallographic c axis. The application of a magnetic field along the b axis induces two second-order phase transitions. We propose that the anisotropy and complex phase diagram result from the interplay between strong geometrical frustration and spin-orbit interaction necessary for the description of this fascinating magnetic system.

Magnetic excitations in the spin-ladder material (C5H12N)2CuBr4 (BPCB) are probed by high-resolution multifrequency electron spin resonance (ESR) spectroscopy. Our experiments provide a direct evidence for a pronounced anisotropy (~5% of the dominant exchange interaction), that is in contrast to a fully isotropic spin-ladder model employed for this system previously. It is argued that this anisotropy in BPCB is caused by spin-orbit coupling, which appears to be important for describing magnetic properties of this compound. The zero-field zone-center gap in the excitation spectrum of BPCB, Δ0/kB = 16.5 K, is detected directly. Furthermore, an ESR signature of the interladder exchange interactions is obtained. The detailed characterization of the anisotropy in BPCB completes the determination of the full spin hamiltonian of this exceptional spin-ladder material and shows ways to study anisotropy effects in spin ladders.

A systematic multi-frequency electron spin resonance (ESR) study of the spin-ladder material (C5H12N)2CuBr4 (known as BPCB) and its deuterated analog have been performed at temperatures down to 1.3 K in magnetic fields up to 16 T. The energy gap in the magnetic excitation spectrum at k = 0, Delta/kB = 16.45 K, was observed directly, confirming the existence of Dzyaloshinskii-Moriya interaction in this compound. A small (» 140 mK) splitting between the levels of the excited spin-triplet confirmed the presence of a weak interladder coupling. The temperature evolution of the ESR excitation spectrum in BPCB revealed its very unusual behavior, whose origin is discussed.

We explored the possibility of using a genetic approach to inhibit integrin-mediated endothelial cell adhesion and survival. We constructed recombinant adenoviruses (Ads) expressing chimeric proteins consisting of the cytoplasmic and transmembrane domains of integrin beta1 (CH1), beta3 (CH3) or the beta1 transmembrane domain alone (CH2) connected to the extracellular domain of L3T4 placed under the control of the CMV promoter (AdCMV) or the endothelial cell specific Tie-1 promoter (AdTie). All constructs were expressed in a dose- and time-dependent manner with over 90% of cells expressing the constructs within 24 h (AdCMVs) or 72 h (AdTies) after infection. Confluent monolayers of HUVEC infected with AdCMVCH1 or AdCMVCH3 detached from the substrate in a time- and dose-dependent manner with over 95% of the cells being detached 2 days (AdCMVs) or 3 to 4 days (AdTies) after infection. Cell detachment was preceded by the disruption of focal adhesions and reorganization of the actin cytoskeleton and was associated with a reduced ligand-binding activity of beta1, while cell surface density of beta1 integrins remained unchanged. Detached cells failed to re-adhere to different matrix proteins, without, however, any specificity toward beta1 or beta3 integrin-mediated adhesion. Upon detachment, HUVEC rapidly died by apoptosis. These results demonstrate that dominant negative inhibition of integrin function is an effective approach to disrupt endothelial cell adhesion and survival in vitro.