Search results for "Oxide"

A Certain Mathematical Model of the Glass Fibre Material Production

1997

There is considered the full mathematical model of chemical reactions on the surface of glass fibre material that was imbedded in the flow of acid solution and was pulled longitudionally. Self-similar forms of this model are obtained and their approximations by monotone schemes of differences are proposed. Some special cases which make possible to get the analytic solutions are underlined. The self-similar forms of the differential equations of the substances transport allow to calculate the emission of the alkaline oxide from the glass fibre material under the influence of the acid solution flow. Some conclusions with practical significance for the technological process is made up accordin…

2D dynamical arrest transition in a mixed nanoparticle-phospholipid layer studied in real and momentum spaces

2015

AbstractWe investigate the interfacial dynamics of a 2D self-organized mixed layer made of silica nanoparticles interacting with phospholipid (DPPC) monolayers at the air/water interface. This system has biological relevance, allowing investigation of toxicological effects of nanoparticles on model membranes and lung surfactants. It might also provide bio-inspired technological solutions, exploiting the self-organization of DPPC to produce a non-trivial 2D structuration of nanoparticles. The characterization of interfacial dynamics yields information on the effects of NPs on the mechanical properties, important to improve performances of systems such as colloidosomes, foams, creams. For thi…

High Temperature Corrosion Behaviour of Coated F17Ti Stainless Steel

1997

Nous avons etudie l'effet de revetements de chromine et d'alumine sur le comportement de l'acier inoxydable F17Ti. Les films ont ete formes a la surface de l'alliage par pyrolyse de la vapeur d'un precurseur organometallique (MOCVD). Cette technique permet egalement de preparer des oxydes d'elements de terres rares. Ceci nous a conduit a envisager la formation de couches barrieres dopees par un element actif, soit par depots successifs, soit par codeposition de chromine ou d'alumine et d'un oxyde de terre rare, suivi d'un traitement de recuit d'homogeneisation. Les revetements ainsi obtenus ont ete caracterises par microscopie electronique a balayage, microanalyse X, diffraction des rayons …

1991

Preparation des polymeres (CHR-CH 2 SO 2 ) (R=(CH 2 ) 9 N + Me 2 (CH 2 ) 3 SO 3 − , (CH 2 ) 8 CO[NC 4 H 8 N + (Me)([CH 2 ] 3 SO 3 − )] et R=CH 2 OCH 2 CHOHCH 2 N + Me(C 10 H 21 )(CH 2 ) 3 SO 3 − ) par copolymerisation spontanee des sels d'ammonium vinyliques correspondants avec SO 2 dans l'eau. Leurs proprietes de surface et de solubilisation de molecules hydrophobes en solution aqueuse sont caracteristiques de polysavons

Carbon monoxide improves cardiac energetics and safeguards the heart during reperfusion after cardiopulmonary bypass in pigs

2004

Ischemia-reperfusion injury, a clinical problem during cardiac surgery, involves worsened adenosine trisphosphate (ATP) generation and damage to the heart. We studied carbon monoxide ( CO) pretreatment, proven valuable in rodents but not previously tested in large animals, for its effects on pig hearts subjected to cardiopulmonary bypass with cardioplegic arrest. Hearts of CO-treated pigs showed significantly higher ATP and phosphocreatine levels, less interstitial edema, and apoptosis of cardiomyocytes and required fewer defibrillations after bypass. We conclude that treatment with CO improves the energy status, prevents edema formation and apoptosis, and facilitates recovery in a clinical…

Subcellular localization and characterization of nitric oxide synthase(s) in endothelial cells: physiological implications.

1994

Endothelial cells (EC) contain a constitutive Ca2+/calmodulin-dependent nitric oxide (NO) synthase (cNOS) which plays an important role in the local control of vascular tone. We compared the subcellular distribution of this enzyme in cultured and freshly isolated pig EC by determination of specific cNOS activity and immunoblot analysis. Similar studies were also performed with cultured and freshly isolated bovine and cultured human EC. Enzyme activity was predominantly (> 70%) associated with the particulate fraction of all EC types tested and was highest in freshly isolated porcine EC. Both specific cNOS activity and immunoreactivity were substantially higher (> 3-fold) in th…

Instant labeling of therapeutic cells for multimodality imaging

2020

Autologous therapeutic cells are typically harvested and transplanted in one single surgery. This makes it impossible to label them with imaging biomarkers through classical transfection techniques in a laboratory. To solve this problem, we developed a novel microfluidic device, which provides highly efficient labeling of therapeutic cells with imaging biomarkers through mechanoporation. Methods: Studies were performed with a new, custom-designed microfluidic device, which contains ridges, which compress adipose tissue-derived stem cells (ADSCs) during their device passage. Cell relaxation after compression leads to cell volume exchange for convective transfer of nanoparticles and nanoparti…

Neuronal nitric oxide synthase modulates maturation of human dendritic cells.

2010

AbstractDendritic cells (DCs) are the most potent APCs of the immune system. Understanding the intercellular and intracellular signaling processes that lead to DC maturation is critical for determining how these cells initiate T cell-mediated immune processes. NO synthesized by the inducible NO synthase (iNOS) is important for the function of murine DCs. In our study, we investigated the regulation of the arginine/NO-system in human monocyte-derived DCs. Maturation of DCs induced by inflammatory cytokines (IL-1β, TNF, IL-6, and PGE2) resulted in a pronounced expression of neuronal NOS (nNOS) but only minimal levels of iNOS and endothelial NOS were detected in human mature DCs. In addition, …

Mycoplasma fermentans-derived lipid inhibits class II major histocompatibility complex expression without mediation by interleukin-6, interleukin-10,…

1996

Mycoplasma cause several diseases in man and animals. Some strains can chronically infect humans, leading to fever or inflammatory syndromes such as arthritis, particularly in immunosuppressed patients. A set of pathogenicity factors shared by many mollicutes may be membrane components that activate macrophages to secrete cytokines and other inflammatory mediators. Mycoplasma-derived high molecular weight material (MDHM) is a macrophage-activating amphiphilic lipid which was purified from Mycoplasma fermentans. We studied the influence of MDHM on the expression of major histocompatibility complex (MHC) class II molecules by mouse resident peritoneal macrophages with an ELISA. Highly purifie…

Skin Dendritic Cells in Murine Cutaneous Leishmaniasis

2002

Studies of the immunopathogenesis of Leishmania major-induced murine cutaneous leishmaniasis provide a framework for understanding the evolution of L. major infection of skin in humans and the foundation for rationale vaccine design. Experiments in which infection is initiated with "suprap hysiologic" numbers of parasites clearly identify Th-derived type I cytokines as essential participants in macrophage activation and macrophage nitric oxide production as prerequisite for parasite control. Dendritic cells, rather than macrophages, appear to be responsible for L. major-specific Th priming in these studies. Recent studies of murine cutaneous leishmaniasis in a model system in which infectio…