Les sutures en fil d'acier pour la fermeture de l'abdomen lors de la relaparotomie compliquée

Cet article décrit la suture de la ligne blanche lors de relaparotomie à la suite de complications incisionnelles par infection et éventration chez 3 chevaux. La mise en place de points de soutien en matelassier horizontaux avec un fil de suture en acier inoxydable à 10 cm de l’incision a permis d’éviter la déhiscence de la plaie et une hernie incisionnelle aux conséquences catastrophiques. À court terme, ces trois cas ont développé un drainage incisionnel important s’accompagnant d’une infection et, à long terme, deux d’entre eux ont présenté une hernie incisionnelle. Les points de soutien en fil d’acier inoxydable ont permis de renforcer efficacement la suture de la ligne blanche en présence de complications incisionnelles lors de la reprise chirurgicale d’une laparotomie

RBS raw data for publication "Tuning the Co/Sr stoichiometry of SrCoO2.5 thin films by RHEED assisted MBEgrowth"

RBS raw date for publication "Tuning the Co/Sr stoichiometry of SrCoO2.5 thin films by RHEED assisted MBEgrowth" Simulation results using SIMNRA included as wel

Tuning the Co/Sr stoichiometry of SrCoO2.5_{2.5} thin films by RHEED assisted MBEgrowth

Strontium cobaltite (SrCoO2.5+δ, SCO) is a fascinating material because of its topotactic structural phase transition caused by a change in oxygen stoichiometry. In the brownmillerite phase (δ = 0) it is an insulating antiferromagnet whereas in the perovskite phase (δ = 0.5) it is a conducting ferromagnet. In contrast, the impact of the varying Co/Sr stoichiometry on the structure has not yet been studied in SCO thin films. Using molecular beam epitaxy we have fabricated SCO thin films of varying Co/Sr stoichiometry. Films with Co excess exhibit a brownmillerite crystal structure with CoO precipitates within the thin film and on the surface. Co deficient films are amorphous. Only for 1:1 stoichiometry a pure brownmillerite structure is present. We find a clear dependence of the Reflection High Energy Electron Diffraction (RHEED) pattern of these thin films on the stoichiometry. Interestingly, RHEED is very sensitive to a Co excess of less than 12% while x-ray diffraction fails to reveal that difference. Hence, using RHEED, the stoichiometry of SCO can be evaluated and tuned in-situ to a high degree of precision, which allows for a quick adjustment of the growth parameters during a sample series

Impact of growth kinetics on the interface morphology and magnetization in La 1/3 Sr 2/3 FeO 3 /La 2/3 Sr 1/3 MnO 3 heterostructures

The ability to create atomically perfect, epitaxial heterostructures of correlated complex perovskite oxides using state-of-art thin film deposition techniques has generated new physical phenomena at engineered interfaces. Here we report on the impact of growth kinetics on the magnetic structure and exchange coupling at the interface in heterostructures combining layers of antiferromagnetic La1/3Sr2/3FeO3 (LSFO) and ferromagnetic La2/3Sr1/3MnO3 (LSMO) on (0 0 1)-oriented SrTiO3 (STO) substrates. Two growth orders are investigated, (a) LSMO/LSFO/STO(0 0 1) and (b) LSFO/LSMO/STO(0 0 1), where the LSFO layer is grown by molecular beam epitaxy and the LSMO layer by high oxygen pressure sputtering. The interface has been investigated using electron microscopy and polarized neutron reflectometry. Interdiffusion over seven monolayers is observed in LSMO/LSFO (a) with an almost 50% reduction in magnetization at the interface and showing no exchange coupling. However, the exchange bias effect ( mT at 10 K) could be realized when the interface is atomically sharp, as in LSFO/LSMO (b). Our study therefore reveals that, even for well ordered and lattice-matched structures, the kinetics involved in the growth processes drastically influences the interface quality with a strong correlation to the magnetic properties