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991.
Julie Boisramé-Helms Xavier Delabranche Andrey Klymchenko Jocelyne Drai Emilie Blond Fatiha Zobairi Yves Mely Michel Hasselmann Florence Toti Ferhat Meziani 《Lipids》2014,49(11):1091-1099
The aim of this study was to assess how lipid emulsions for parenteral nutrition affect lipopolysaccharide (LPS)‐induced acute monocyte inflammation in vitro. An 18 h long LPS induced human monocyte leukemia cell stimulation was performed and the cell‐growth medium was supplemented with three different industrial lipid emulsions: Intralipid®, containing long‐chain triglycerides (LCT—soybean oil); Medialipid®, containing LCT (soybean oil) and medium‐chain triglycerides (MCT—coconut oil); and SMOFlipid®, containing LCT, MCT, omega‐9 and ‐3 (soybean, coconut, olive and fish oils). Cell viability and apoptosis were assessed by Trypan blue exclusion and flow cytometry respectively. Monocyte composition and membrane remodeling were studied using gas chromatography and NR12S staining. Microparticles released in supernatant were measured by prothrombinase assay. After LPS challenge, both cellular necrosis and apoptosis were increased (threefold and twofold respectively) and microparticle release was enhanced (sevenfold) after supplementation with Medialipid® compared to Intralipid®, SMOFlipid® and monocytes in the standard medium. The monocytes differentially incorporated fatty acids after lipid emulsion challenge. Finally, lipid‐treated cells displayed microparticles characterized by disrupted membrane lipid order, reflecting lipid remodeling of the parental cell plasma membrane. Our data suggest that lipid emulsions differentially alter cell viability, monocyte composition and thereby microparticle release. While MCT have deleterious effects, we have shown that parenteral nutrition emulsion containing LCT or LCT and MCT associated to n‐3 and n‐9 fatty acids have no effect on endotoxin‐induced cell death and inflammation. 相似文献
992.
993.
Andrey Lyalin Akira Nakayama Kohei Uosaki Tetsuya Taketsugu 《Topics in Catalysis》2014,57(10-13):1032-1041
Adsorption and catalytic activation of the molecular oxygen on the hexagonal boron nitride (h-BN) monolayer supported on Ni(111) and Cu(111) surfaces have been studied theoretically using density functional theory. It is demonstrated that an inert h-BN monolayer can be functionalized and become catalytically active on the transition metal support as a result of mixing of the metal d and h-BN π bands. 相似文献
994.
Andrey Babenko Irina Temnikova Ustinya Bokova 《The International journal of environmental studies》2014,71(5):671-677
The possibility to use soil-inhabiting rove beetles (Coleoptera, Staphylinidae) as an indicator of disturbed forest areas has been studied. The studies of Staphylinidae succession and changes in beetles’ communities in the couse of demutational successions took place in the dark coniferous forests of the Kuznetsky Alatau. The specific species for all the stages of secondary succession on the clearings of different ages were marked. For instance, Philonthus lepidus Grav. indicates meadow stages of succession in fir forests, while Tachinus marginellus Grav., Tachinus elongatus Gyll and Philonthus setosus Sahlb. are typical for primary forests. In pine forests, Tachyporus obtusus L. may serve as a good indicator for initial stages of succession, while Staphylinus erythropterus L. and Tachinus marginatus Gyll. are typical for old growth forests. A trend of decrease in the level of aggregation during the process of restoration of primary plant communities has been registered for all types of forest ecosystems. 相似文献
995.
Alexey Redkov Semen Chervinskii Alexander Baklanov Igor Reduto Valentina Zhurikhina Andrey Lipovskii 《Nanoscale research letters》2014,9(1):606
Growth of self-assembled metal nanoislands on the surface of silver ion-exchanged glasses via their thermal processing in hydrogen followed by out-diffusion of neutral silver is studied. The combination of thermal poling of the ion-exchanged glass with structured electrode and silver out-diffusion was used for simple formation of separated groups of several metal nanoislands presenting plasmonic molecules. The kinetics of nanoisland formation and temporal evolution of their size distribution on the surface of poled and unpoled glass are modeled.
PACS
78.67.Sc (nanoaggregates; nanocomposites); 81.16.Dn (self-assembly); 68.35.bj (surface structure of glasses); 64.60.Qb (Nucleation); 81.16.Nd (micro- and nanolithography) 相似文献996.
Kuznetsov AV 《Nanoscale research letters》2011,6(1):100
The aim of this article is to propose a novel type of a nanofluid that contains both nanoparticles and motile (oxytactic)
microorganisms. The benefits of adding motile microorganisms to the suspension include enhanced mass transfer, microscale
mixing, and anticipated improved stability of the nanofluid. In order to understand the behavior of such a suspension at the
fundamental level, this article investigates its stability when it occupies a shallow horizontal layer. The oscillatory mode
of nanofluid bioconvection may be induced by the interaction of three competing agencies: oxytactic microorganisms, heating
or cooling from the bottom, and top or bottom-heavy nanoparticle distribution. The model includes equations expressing conservation
of total mass, momentum, thermal energy, nanoparticles, microorganisms, and oxygen. Physical mechanisms responsible for the
slip velocity between the nanoparticles and the base fluid, such as Brownian motion and thermophoresis, are accounted for
in the model. An approximate analytical solution of the eigenvalue problem is obtained using the Galerkin method. The obtained
solution provides important physical insights into the behavior of this system; it also explains when the oscillatory mode
of instability is possible in such system. 相似文献
997.
Brunk E Ashari N Athri P Campomanes P de Carvalho FF Curchod BF Diamantis P Doemer M Garrec J Laktionov A Micciarelli M Neri M Palermo G Penfold TJ Vanni S Tavernelli I Rothlisberger U 《Chimia》2011,65(9):667-671
The Laboratory of Computational Chemistry and Biochemistry is active in the development and application of first-principles based simulations of complex chemical and biochemical phenomena. Here, we review some of our recent efforts in extending these methods to larger systems, longer time scales and increased accuracies. Their versatility is illustrated with a diverse range of applications, ranging from the determination of the gas phase structure of the cyclic decapeptide gramicidin S, to the study of G protein coupled receptors, the interaction of transition metal based anti-cancer agents with protein targets, the mechanism of action of DNA repair enzymes, the role of metal ions in neurodegenerative diseases and the computational design of dye-sensitized solar cells. Many of these projects are done in collaboration with experimental groups from the Institute of Chemical Sciences and Engineering (ISIC) at the EPFL. 相似文献
998.
Hongkang Wang Kunpeng Dou Wey Yang Teoh Yawen Zhan Tak Fu Hung Feihu Zhang Jiaqiang Xu Ruiqin Zhang Andrey L. Rogach 《Advanced functional materials》2013,23(38):4847-4853
Hierarchical SnO2 nanoflowers, assembled from single‐crystalline SnO2 nanosheets with high‐index (11$ \bar 3 $ ) and (10$ \bar 2 $ ) facets exposed, are prepared via a hydrothermal method using sodium fluoride as the morphology controlling agent. Formation of the 3D hierarchical architecture comprising of SnO2 nanosheets takes place via Ostwald ripening mechanism, with the growth orientation regulated by the adsorbate fluorine species. The use of Sn(II) precursor results in simultaneous Sn2+ self‐doping of SnO2 nanoflowers with tunable oxygen vacancy bandgap states. The latter further results in the shifting of semiconductor Fermi levels and extended absorption in the visible spectral range. With increased density of states of Sn2+‐doped SnO2 selective facets, this gives rise to enhanced interfacial charge transfer, that is, high sensing response, and selectivity towards oxidizing NO2 gas. The better gas sensing performance over (10$ \bar 2 $ ) compared to (11$ \bar 3 $ ) faceted SnO2 nanostructures is elucidated by surface energetic calculations and Bader analyses. This work highlights the possibility of simultaneous engineering of surface energetics and electronic properties of SnO2 based materials. 相似文献
999.
Marcio Andrey Teixeira Paulo Roberto Guardieiro 《International Journal of Communication Systems》2013,26(8):1038-1053
IEEE 802.16e is a telecommunication standard technology designed to support a wide variety of multimedia applications. It defines five service classes, each one with its respective QoS requirements, but does not define the scheduling algorithm for these service classes. In this paper, an adaptive packet scheduling algorithm for the uplink traffic in IEEE 802.16e networks is proposed. This algorithm is designed to be completely dynamic, mainly in networks that use various modulation and coding schemes (MCSs). The algorithm is applied directly to the bandwidth request queues in the base station (BS) and aims at supporting the real‐time and non‐real‐time applications. Using a cross‐layer approach and the states of the bandwidth request queues in the BS, a new deadlines based scheme was defined, aiming at limiting the maximum delay to the real‐time applications. Moreover, this algorithm interacts with the polling management mechanisms of the BS and controls the periodicity of sending unicast polling to the real‐time and non‐real‐time service connections, in accordance with the QoS requirements of the applications. The proposed algorithm was evaluated by means of modeling and simulation in environments where various MCSs were used and also in environments where only one type of modulation was used. The simulations showed satisfactory results in both environments. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
1000.
3D blading of a high-pressure and low-pressure steam turbine stage is optimized using Nelder–Mead method of deformed polyhedron. Values of the minimized objective function, i.e. stage losses with the exit energy are found from 3D viscous compressible flow computations, including turbulence effects. Among the optimized parameters are stator and rotor blade numbers and stagger angles, rotor blade twist angle, stator blade sweep and lean, both straight and compound. The blade sections (profiles) are assumed not to change during the optimization. There are constraints imposed on the design parameters, including the mass flow rate and stage reaction. Optimization gives designs with new 3D blade stacking lines, and with increased efficiencies, compared with the original design. 相似文献