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Background: There is no recommendation for treating pulmonary hypertension (PH) when associated with chronic obstructive pulmonary disease (COPD). Objective: To evaluate the effect of PH-specific therapy in patients with COPD. Methods: All successive patients with severe PH [mean pulmonary arterial pressure (mPAP) ≥35 mm Hg] and COPD, who received specific PH medication and who underwent right heart catheterization at baseline and after 3-12 months of treatment, were analyzed from a prospective database. Results: Twenty-six patients were included with a median follow-up of 14 months. Mean forced expiratory volume in 1 s was 57 ± 20% of predicted, and mean forced expiratory volume in 1 s/forced vital capacity was 47 ± 12%. Dyspnea was New York Health Association classification stage (NYHA) II in 15%, NYHA III in 81% and NYHA IV in 4%. First-line treatments were endothelin receptor antagonists in 11 patients, phosphodiesterase-5 inhibitors in 11 patients, calcium blocker in 1 patient, combination therapy in 3 patients including 2 with a prostanoid. After 6 ± 3 months, pulmonary vascular resistance decreased from 8.5 ± 3 to 6.6 ± 2 Wood units (p < 0.001), with significant improvement of cardiac index from 2.44 ± 0.43 to 2.68 ± 0.63 liters × min × m^-2 (p = 0.015) and mPAP from 48 ± 9 to 42 ± 10 mm Hg (p = 0.008). There was no significant difference in dyspnea, 6-min walking distance, echocardiographic parameters or N-terminal pro-brain natriuretic peptide levels. There was no significant difference in arterial oxygen saturation after 3-12 months of treatment. Conclusions: Specific PH medications may improve hemodynamic parameters in COPD patients with severe PH. Appropriate prospective randomized studies are needed to evaluate the potential long-term clinical benefit of treatment.

International audienceThis paper investigates the effects of different surface treatments on the mechanical resistance of interface between wires of NiTi shape memory alloy and silicone rubber. Three different treatments were used; primer, plasma and combination of both. The wires deoxidation effects have also been studied. In order to characterize the interface properties in such composite material, pull-out tests were carried out by means of a home-made device. This test allows us to evaluate the mechanical resistance of the interface in terms of the maximum force reached during the test. First, results show that the debonding force is not higher after the wires deoxidation. This preparation is therefore not necessary. Second, using a primer PM820 and plasma separately leads to a significant improvment of the mechanical resistance. Third, the combination of these treatments (primer followed by plasma) and a longer time of exposure to the plasma alone get the debonding force higher. Consequently, NiTi/silicone rubber interface improved only by means of plasma offers a new way to obtain biocompatible interfaces in such composite material

A unique approach based on the colloidal route allowing the synthesis of monodisperse bimetallic, trimetallic, tetrametallic and pentametallic nanoparticles with diameters around 5 nm as solid solutions.

We report a new and versatile colloidal route towards the synthesis of nanoalloys with controlled size and chemical composition in the solid solution phase (without such phases segregations as core-shell...

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The thermomechanical (dilatometric, tensile, and fatigue) behavior of Al-based metal matrix composites (MMCs) is investigated. These composites are reinforced by quasi-unidirectional (quasi-UD) woven fabric preforms with 90 pct of continuous fibers in the longitudinal direction and 10 pct in the transverse direction. The two composite systems investigated feature a highly ductile matrix (AU2: Al-2Cu wt pct) with a strongly bonded fiber-matrix interface (N610 alumina fibers) and an alloyed, high-strength matrix (A357: Al-7Si-0.6Mg wt pct) with a weak fiber-matrix interface (K139 carbon fibers). Microstructural investigation of the tested specimens has permitted identification of the specific characteristics of these composites: undulation of the longitudinal bundles, presence of the straight transverse bundles, interply shearing, and role of brittle phases. Moreover, simple semiquantitative models (e.g., interply shearing) have enabled explanation of the specific mechanical behavior of these quasi-UD composites, which exhibit high tensile and fatigue strengths, as compared with the corresponding pure UD composites. Knowledge of the specific characteristics and mechanical behavior of these quasi-UD composites will facilitate the further investigation of the (0, Ϯ45, 90 deg) quasi-UD laminates (Part II). At a more theoretical viewpoint, the specific geometry and behavior of these quasi-UD composites allows exacerbation of fatigue mechanisms, even more intense than in "model" composites.

Alumina (N610) reinforced pure Al (A9) or Al ± 2 wt-%Cu alloy (AU2) unidirectional (UD) composites which combine a highly ductile matrix with a strong interface bonding, present high static and dynamic mechanical performances. In the present paper, the fatigue behaviour of quasi-UD N610zA9 and N610zAU2 composites is investigated. Notwithstanding the presence of the transverse bundles, the longitudinal behaviour in tension and fatigue of these quasi-UD composites is nearly equivalent to that of the pure UD. Only in the case of the N610zAU2 quasi-UD composite, the fatigue limit is about 30% lower than that of the pure UD. Acoustic emission (AE) monitoring correlated with microfractography and microstuctural examinations has enabled identi®cation of different stages in the evolution of damage and the association of these with damage and failure mechanisms. In fatigue, three main damage mechanisms are activated in a sequential and/or superposed mode during a three stage evolution.MST/4542