Gastrointestinal Manifestations of IgA Vasculitis-Henoch-Schönlein Purpura

Immunoglobulin A vasculitis, formerly called Henoch-Schönlein purpura (HSP), is the most common systemic vasculitis in childhood. It is a small-vessel vasculitis mediated by type III hypersensitivity, manifested as rash accompanied by gastrointestinal (GI) symptoms, arthritis, and nephritis. The etiology of this disease (a leukocytoclastic vasculitis) is still uncertain, but immune complexes of IgA and unidentified antigens seem to have a central pathogenic role. Most often the diagnosis is established after the clinical examination; it is easy at first glance when the clinical presentation includes the classic tetrad of rash (nonthrombocytopenic palpable purpura), arthralgia/arthritis, abdominal pain, and renal manifestations but may be difficult when the gastrointestinal manifestations precede the skin purpuric rash. Gastrointestinal involvement is frequently seen and varies from mild symptoms to severe complications; sometimes the gastrointestinal symptoms (colicky abdominal pain, nausea, vomiting, diarrhea, gastrointestinal bleeding) are the first manifestations of the disease. Immunoglobulin A vasculitis is usually a self-limited disease with a benign course, and the treatment is often symptomatic; in severe cases corticosteroids are necessary

Versatile Phase Transfer Method for the Efficient Surface Functionalization of Gold Nanoparticles: Towards Controlled Nanoparticle Dispersion in a Polymer Matrix

In electronic devices based on hybrid materials such as nonvolatile memory elements (NVMEs), it is essential to control precisely the dispersion of metallic nanoparticles (NPs) in an insulating polymer matrix such as polystyrene in order to control the functionality of the device. In this work the incorporation of AuNPs in polystyrene films is controlled by tuning the surface functionalization of the metallic nanoparticles via ligand exchange. Two ligands with different structures were used for functionalization: 1-decanethiol and thiol-terminated polystyrene. This paper presents a versatile method for the modification of gold nanoparticles (AuNPs) with thiol-terminated polystyrene ligands via phase transfer process. An organic colloid of AuNPs (5±1 nm diameter) is obtained by the phase transfer process (from water to toluene) that allows exchanging the ligand adsorbed on AuNPs surface (hydrophilic citrate/tannic acid to hydrophobic thiols). The stability, size distribution, and precise location of modified AuNPs in the polymer matrix are obtained from UV-Vis spectroscopy, dynamic light scattering (DLS), and electron tomography. TEM tomographic 3D imaging demonstrates that the modification of AuNPs with thiol-terminated polystyrene results in homogeneous particle distribution in the polystyrene matrix compared to 1-decanethiol modified AuNPs for which a vertical phase separation with a homogeneous layer of AuNPs located at the bottom of the polymer matrix was observed.This work was supported by FP7-NMP-2010-SMALL-4 Program (“Hybrid Organic/Inorganic Memory Elements for Integration of Electronic and Photonic Circuitry,” HYMEC), Project no. 263073. Eric Gonthier is acknowledged for technical support in the preparation of hybrid thin films. Scientific work was supported by the Polish Ministry of Science and Higher Education Funds for Science in 2011–2014 allocated for the cofunded international project

Efficient hierarchically structured composites containing cobalt catalyst for clean synthetic fuel production from Fischer-Tropsch synthesis

We report a straightforward preparation method to synthesize hierarchical composite consisting of TiO2-coated multi-walled carbon nanotubes (CNTs) decorating a macroscopic host structure of alpha-Al2O3. The obtained composite possesses moderate specific surface area and very open porous structure, as well as moderate interaction with active sites, which significantly improve the cobalt nanoparticles dispersion and the mass diffusion during the reaction. The Co/TiO2/CNT-alpha-Al2O3 (CoTiCNTA) catalyst is then used in the Fischer-Tropsch synthesis (FTS) process. This hierarchical catalyst achieves a FTS rate to C5+ of 0.80 g(C5+) g(cat)(-1) h(-1) along with a long-chain hydrocarbons (C5+) selectivity of 85%, which can be pointed out as the most outstanding noble promoter-free catalyst for the FTS process. The as-synthesized catalyst also exhibits an extremely high stability as a function of time on stream which is also one of the prerequisites for the development of future FTS catalysts, especially for the Biomass-to-Liquids process where trace amount of impurities and/or moisture could have an impact on the catalyst stability. The present work also introduces a new investigation methodology based on the use of zero field Co-59 NMR, which allows one to map in a precise manner the cobalt active phase distribution and to correlate it with the FTS performance. It is expected that such technique would be extremely helpful for the understanding of the catalyst structure-performance relationship and for future optimization in the FTS process as well as in other fields of investigation where cobalt particles are involved. (C) 2014 Elsevier Inc. All rights reserved

Etude de la structure de films minces de nitrure de titane et d'aluminium Ti1-xAlxN (0 <= x <= 1) et de son rôle sur l'indentation

Une série de films Ti1-xAlxN (0 = 0,68). Pour Ti0,32Al0,68N, DRX et EXAFS ont révélé la coexistence de domaines cubiques, dans les zones mal cristallisées, et de domaines hexagonaux, dans les zones cristallisées. La microstructure analysée en MET est colonnaire pour toute la série des films Ti1-xAlxN. L'examen des empreintes d'indentation réalisées à différentes charges montre que les couches de Ti1-xAlxN deviennent de plus en plus fragiles avec l'augmentation de la teneur en Al. Pour les films riches en Ti, la grande proportion de joints de grains permet le glissement des colonnes les unes contre les autres. Pour les films riches en Al, le nombre des fissures dans l'épaisseur augmente avec la proportion d'Al dans le film. De plus, une courbure des colonnes (constituées par des grains de symétrie hexagonale) sous la pointe de l'indenteur induit une désorientation de quelques degrés de ces cristallites autour de la direction principale de croissance.A serie of Ti1-xAlxN films (0 = 0.68). For Ti0_32Al0.68N, DRX and EXAFS probes revealed the coexistence of cubic like-TiN areas, in the badly crystallized zones, and of hexagonal like-AlN areas, in the crystallized zones. Column-like growth for all Ti1-xAlxN films is highlighted by TEM study. The indentation prints examination, carried out at various loads, shows that the Ti1-xAlxN coatings become more and more brittle with increasing the Al content. For Ti-rich films, high grain boundaries proportion allows the columns sliding ones against the others. For Al-rich films, the number of cracks within thickness increase according to the Al content. Moreover, the bending of the columns under the indentation tip (consisted of hexagonal symmetry grains) induced few degree displacement of these crystallites around the principal growth direction.MULHOUSE-SCD Sciences (682242102) / SudocSudocFranceF

Négation et transcendance dans l'œuvre de Christian Gabrielle Guez Ricord

L'œuvre - littéraire, graphique, picturale - de Christian Gabrielle Guez Ricord est abordée dans ce travail à partir de ses propres sources littéraires et philosophiques (romantisme, courants mystiques et ésotériques des trois monothéismes) mais aussi artistiques (Annonciations italiennes, gravures alchimiques, icônes byzantines). Constitutive de l'œuvre, l'expérience de l'Ange ne peut se dire que par le négatif. Ce travail analyse successivement les modalités expressives qui permettent à l'indicible et à l'invisible d'accéder à la représentation. L'ouverture opérée vers ce qui échappe à toute nomination par la deixis discursive et l'emploi spécifique du préfixe "trans-", l'exploration de la valeur cryptique du signe, l'éclosion de la vision symbolique grâce à l'imagination créatrice déplacent sans cesse les frontières du figurable et du lisible. Centre irradiant de l'œuvre, l'Annonciation fonde le "non-lieu", la scène énonciative nécessaire à une parole rituelle, créatrice et efficace. Un dossier iconographique et une monographie critique complètent les analyses.This work deals with Christian Gabrielle Guez Ricord's literary, graphic and pictorial oeuvre starting not only from its own literary and philosophical sources (Romanticism, mystical and esoteric traditions of the three monotheisms), but also artistic ones (Italian Annunciations, alchemical engravings, Byzantine icons). Part and parcel of Guez Ricord's oeuvre, the Angel experience can only be rendered by the negative mode. Our work analyses successively the expressive modalities through which the unsayable and the invisible gain access to means of representation. Several techniques used by Guez Ricord relentlessly push the boundaries of the figurable and the legible: the use of discursive deixis and of the prefix "trans-" which point to what cannot be named, the exploration of the cryptic value of the sign, the emergence of the symbolic vision owing to creative imagination. At the heart of the oeuvre lies the scene of the Annunciation which is turned into a "non-place", an enunciative scene indispensable to ritual, creative and efficient speech.PARIS4-BU Serpente (751052129) / SudocPARIS-BIB.LITTERAIRE J.DOUCET (751055228) / SudocSudocFranceF

Direct Insight into the Confinement Effect of WS 2 Nanostructures in an Ordered Carbon Matrix

International audienceA new growth mechanism of WS2 nanostructures with well-defined shapes (nanocages or nanotubes), induced by a confinement effect in a mesoporous structure, is reported. As evidenced by high resolution electron microscopy, the growth of these peculiar structures is governed by a restructuration mechanism that occurs in an ordered mesoporous carbon matrix with a nanometric pore size via a one-pot synthesis method (soft-template process) in which W-based clusters are initially dispersed in the carbon walls. During a thermal treatment carried in an Ar/H2S gas mixture and a carbonaceous reductive atmosphere, small WS2 nanolayers stacked and shaped as nanoribbons are produced in a first step within the mesopores at 350 °C. In the second step, at higher sulfidation temperature, a solid/gas growth mechanism occurs in which H2S and W gaseous species (originating from the W clusters) decompose and react on initially formed WS2 nanoribbon seeds. That leads to a spatially restricted growth with the progressive formation of curved WS2 nanolayers characterized by ellipsoidal–based shapes characteristic of the inorganic fullerenes (at 550 °C) and finally to cylindrical shapes similar to the typical structures observed for most of inorganic nanotubes (at 750 °C)

Natural course of nonmalignant partial portal vein thrombosis in cirrhotic patients

Background/Aim: Portal vein thrombosis (PVT) has a high incidence in patients with liver cirrhosis and determines a poor prognosis of hepatic disease. The aim of our study was to define the natural course of partial PVT in cirrhotic patients, including survival and decompensation rates. Patients and Methods: We performed a prospective, cohort study, in a tertiary referral center. There were 22 cirrhotic patients with partial nonmalignant PVT, without anticoagulant treatment, who were followed-up between January 2011 and October 2013. All patients were evaluated by Doppler abdominal ultrasound and computed tomography. Kaplan-Meier method was used to determine the difference in clinical events between the study subgroups. Results: After a mean follow-up period of 20.22 months, partial PVT improved in 5 (22.73%), was stable in 11 (50%), and worsened in 6 (27.27%) patients. Hepatic decompensation rate at 6 and 18 months was higher in patients with worsened PVT than in those with stable/improved PVT (50% vs. 25%, P < 0.0001 and 100% vs. 56.25%, P < 0.0001, respectively). The survival rate at 6 months was 66.66% in worsened PVT group vs. 81.25% (P = 0.005) in stable/improved group, and 16.66% vs. 81.25% (P < 0.0001) at 18 months, respectively. Multivariate analysis showed that Model of End-Life Disease was the independent predictor of hepatic decompensation [hazard ratio (HR) 1.42; 95% confidence interval (CI): 1.08-1.87, P = 0.012] and survival (HR 1.76; 95% CI: 1.06-2.92, P = 0.028). Conclusions: Nonmalignant partial PVT remained stable/improved in over half of cirrhotic patients and aggravated in more than one fourth in whom it negatively influenced the survival and decompensation rates

3D imaging of filaments in organic resistive memory devices

International audienceFilaments in organic and hybrid resistive memories are studied by combining advanced characterization techniques. Model ITO/polymer/Ag devices based on a cross-linked polystyrene layer, are investigated with XPS and ToF-SIMS depth profile analysis to provide a quantitative 3D spectroscopy showing conductive filaments forming between the two metal electrodes. Filament formation mechanisms are discussed by comparing ToF-SIMS reconstructions from pristine and electrically operated devices and by analyzing the drift and diffusion of metal cluster by cross-sectional STEM. Filaments are shown to form by the drift of silver from tips like structures which are formed during the top electrode deposition and the counter drift of indium from the ITO. The switching mechanism is interpreted in terms of reversible activation/inactivation of the same conductive path