We studied the crystal and magnetic structure of Ca2RuO4 by different diffraction techniques under high pressure. The observed first order phase transition at moderate pressure (0.5 GPa) between the insulating phase and the metallic high pressure phase is characterized by a broad region of phase coexistence. The following structural changes are observed as function of pressure: a) a discontinuous change of both the tilt and rotation angle of the RuO6-Octahedra at this transition, b) a gradual decrease of the tilt angle in the high pressure phase (p>0.5 GPa) and c) the disappearance of the tilt above 5.5GPa leading to a higher symmetry structure. By single crystal neutron diffraction at low temperature, the ferromagnetic component of the high pressure phase and a rearrangement of antiferromagnetic order in the low pressure phase was observed.

We present an inelastic neutron scattering investigation of Li2CuO2 detecting the long sought quasi-1D magnetic excitations with a large dispersion along the CuO2-chains studied up to 25 meV. The total dispersion is governed by a surprisingly large ferromagnetic (FM) nearestneighbor exchange integral J1 = −228 K. An anomalous quartic dispersion near the zone center and a pronounced minimum near (0,0.11,0.5) r.l.u. (corresponding to a spiral excitation with a pitch angle about 41 •) point to the vicinity of a 3D FM-spiral critical point. The leading exchange couplings are obtained applying standard linear spin-wave theory. The 2 nd neighbor inter-chain interaction suppresses a spiral state and drives the FM in-chain ordering below the Néel temperature. The obtained exchange parameters are in agreement with the results for a realistic five-band extended Hubbard Cu 3d O 2p model and LSDA+U predictions.

Biosurgery is an effective and rapid treatment for the debridement of chronic wounds and the improvement of wound healing. A possible mode of action is the increase in tissue oxygenation. More studies are needed.

The microcirculation of the wound bed is a key parameter for improving granulation tissue formation and, hence, wound healing. The aim of this study was to determine whether a wound dressing comprising collagen/oxidized regenerated cellulose has effects over a short term on wound healing. Wounds were evaluated using a clinical wound score; pain associated with wounds was measured using a visual analogue scale. Wound microcirculation was evaluated using a technique based on noncontact remission spectroscopy. A prospective trial was performed in 40 patients with chronic venous leg ulcers (mean age 74 years; range, 43-93 years; 25 females and 15 males). Patients in group A were treated with PROMOGRAN Matrix (Johnson& Johnson, New Brunswick, NJ) combined with "good" ulcer care for 2 weeks. Control group B consisted of 10 patients who received only good ulcer care. The authors measured a favorable clinical response in 76.9% (group A) versus 66.7% (group B). The mean reduction of ulcer area was statistically significant in group A (P < .05). The wound score improved in group A from 2.28 +/- 1.24 (before treatment) increasing to 3.72 +/- 1.57 (after 1 week; P < .00023) and 4.92 +/- 1.68 (after 2 weeks; P < .000027). In group B, the score improved from 1.44 +/- 1.33 (before treatment) to 3.22 +/- 1.30 (after 1 week; P < .0077). The mean visual analogue pain score before treatment was 8.72 (group A) and 7.88 (group B) (ns, P > .05). After 1 week of treatment, the score dropped to 5.76 (group A) and 6.66 (group B). In the second week, group A patients had a mean pain score of 3.84 compared with the pain score before treatment (P < .05). After 1 week of treatment, in group A there was a decrease in remission spectroscopy, which is considered to reflect an improvement in microcirculation.

No abstract