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991.
Claire Ducrot-Boisgontier Julien Parmentier Luc Delmotte Joël Patarin 《Journal of Materials Science》2009,44(24):6571-6575
Ordered microporous carbons were synthesized by the nanocasting process using EMC-2 zeolite (EMT structure type) and acetylene
as a mould and a carbon precursor, respectively. In this study, the conditions of the synthesis methods for preparing the
ordered microporous carbons were examined. Temperature and duration parameters for the chemical vapour infiltration were optimized
to yield an ordered carbon replica that displays up the three XRD diffraction peaks. This faithful replica exhibits also a
high micropore volume (1.3–1.4 cm3/g) with mainly supermicroporosity, a high specific surface area (>2900 m2/g) and nearly no mesoporosity. The pore size distribution calculated with NLDFT method from nitrogen physisorption data shows
three maxima at 0.6, 1.0 and 1.8 nm diameters. The second is due to the zeolite wall dissolution. The first and the third
are attributed to different types of default. Compared to the classical two-step procedure, the direct infiltration with acetylene
appears an interesting route for the preparation of ordered microporous carbon replicas with high micropore volume. 相似文献
992.
Oudejans Ra?ul R. D.; Michaels Claire F.; Bakker Frank C.; Davids Keith 《Canadian Metallurgical Quarterly》1999,25(2):531
To catch a lofted ball, a catcher must pick up information that guides locomotion to where the ball will land. The acceleration of tangent of the elevation angle of the ball (AT) has received empirical support as a possible source of this information. Little, however, has been said about how the information is detected. Do catchers fixate on a stationary point, or do they track the ball with their gaze? Experiment 1 revealed that catchers use eye and head movements to track the ball. This means that if AT is picked up retinally, it must be done by means of background motion. Alternatively, AT could be picked up by extraretinal mechanisms, such as the vestibular and proprioceptive systems. In Experiment 2, catchers reliably ran to intercept luminous fly balls in the dark, that is, in absence of a visual background, under both binocular and monocular viewing conditions. This indicates that the optical information is not detected by a retinal mechanism alone. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Claire Bell 《World Patent Information》2000,22(4):325
The Patent Information Service of Birmingham Central Library was re-assessed in the light of changing customer requirements and new opportunities to better meet those needs. A substantial funding injection enabled research to be carried out and the results put into practice, e.g., in expanding the range of services – with particular emphasis on helping small and medium enterprise (SME) businesses, and in positive marketing of the services, rather than the previous passive provision of services. The resulting integrated business and intellectual property service was then re-branded as ‘Business Insight' and given wide promotion in the Birmingham area. 相似文献
994.
Maria do Carmo Hespanhol da Silva Claire Isabel Grígoli de Luca Sarantpoulos Newton Pimenta Celio Pasquini 《Packaging Technology and Science》1999,12(6):271-275
This paper describes the development of an analyser intended to measure the concentrations of CO2 and O2 present as part of the gas mixture in the head‐space of food packages. The efficiency of the measuring device was evaluated by analysing the atmosphere of packages containing the following food products: grated Parmesan cheese, milk powder and fresh pasta. A comparison between the results of the analysis performed with the newly developed analyser and those obtained by gas chromatography showed good correlation between the two methods. The O2 and CO2 analyser presented satisfactory accuracy (absolute error smaller than 2.5%, v/v) and precision (relative standard deviation varying from 0.2% to 8.5%). In addition, final results of the levels of both gas types present in the atmosphere submitted to analysis are obtained after about 2 min. The proposed analyser constitutes an alternative solution for the analysis of gases present in the head‐space of packages, especially when gas samples of very small volumes—about 200 μl—are to be used. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
995.
Jose Maria Zapico Lourdes Acosta Miryam Pastor Loganathan Rangasamy Laura Marquez-Cantudo Claire Coderch Irene Ortin Maria Nicolau-Sanus Leonor Puchades-Carrasco Antonio Pineda-Lucena Alejandro Majali-Martinez Pilar Ramos Beatriz de Pascual-Teresa Ana Ramos 《International journal of molecular sciences》2021,22(18)
Osteoarthritis is a degenerative disease, often resulting in chronic joint pain and commonly affecting elderly people. Current treatments with anti-inflammatory drugs are palliative, making the discovery of new treatments necessary. The inhibition of matrix metalloproteinase MMP-13 is a validated strategy to prevent the progression of this common joint disorder. We recently described polybrominated benzotriazole derivatives with nanomolar inhibitory activity and a promising selectivity profile against this collagenase. In this work, we have extended the study in order to explore the influence of bromine atoms and the nature of the S1′ heterocyclic interacting moiety on the solubility/selectivity balance of this type of compound. Drug target interactions have been assessed through a combination of molecular modeling studies and NMR experiments. Compound 9a has been identified as a water-soluble and highly potent inhibitor with activity in MG-63 human osteosarcoma cells. 相似文献
996.
Claire FerchaudJean-Claude Grenier Ye Zhang-SteenwinkelMarc M.A. van Tuel Frans P.F. van BerkelJean-Marc Bassat 《Journal of power sources》2011,196(4):1872-1879
The praseodymium nickelate oxide Pr2NiO4+δ, a mixed conducting oxide with the K2NiF4-type structure, was evaluated as cathode for low temperature solid oxide fuel cells (T = 873 K). The electrochemical performance of the cathode has been improved by optimization of the microstructure of the porous cathode combined with the use of a ceria barrier layer in between the cathode and zirconia electrolyte. Both low polarization and ohmic resistances were obtained using Pr2NiO4+δ-powders with a median particle size of 0.4 μm, and sintering the screen printed layer at a sintering temperature of about 1353 K for 1 h. These manufacturing conditions resulted in a cathode microstructure with well established connections between the cathode particles and good adhesion of the cathode on the electrolyte. Full-sized anode supported cells have been manufactured using the same process conditions for the Pr2NiO4+δ cathode and tested. The best results were obtained when using a dense Ce0.8Gd0.2O1.9 (20CGO) barrier layer. While a complete optimization of the cell preparation has not yet been achieved, the electrochemical performances of anode supported cells with Pr2NiO4+δ are higher than those with the well known state-of-the-art La0.6Sr0.4Fe0.8Co0.2O3−δ (LSFC) material. 相似文献
997.
998.
Lin-Cereghino J Hashimoto MD Moy A Castelo J Orazem CC Kuo P Xiong S Gandhi V Hatae CT Chan A Lin-Cereghino GP 《Yeast (Chichester, England)》2008,25(4):293-299
The methylotrophic yeast, Pichia pastoris, is widely used as a host organism for the expression of heterologous proteins. Currently, the Zeocin and blasticidin resistance genes are the only dominant selectable markers that can be used for primary selection of transformants. In this report we describe new expression vectors that can be used to select directly for P. pastoris transformants using G418 resistance conferred by a modified Tn903kan(r) gene. Compared to other dominant markers, this system is more economical and offers a higher transformation efficiency, due to the small sizes of the cloning vectors, pKAN B and pKANalpha B (GenBank Accession Nos EU285585 and EU285586, respectively). Additionally, multicopy transformants can be generated using these new vectors. 相似文献
999.
Rambeau CM 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2010,368(1931):5225-5248
Palaeoenvironmental research in the Southern Levant presents a series of challenges, partly due to the unequal distribution of palaeoenvironmental records and potential archives throughout the region. Our knowledge of climatic evolution, during the last approximately 25,000 years, is of crucial importance to understand cultural developments. More local, well-dated, multi-proxy studies are much needed to obtain an accurate picture of environmental change in respect of the Late Pleistocene and the Holocene. This contribution reviews the current state of knowledge regarding Late Quaternary palaeoenvironmental changes in the Southern Levant, including some examples of more recent developments in palaeoenvironmental reconstruction in Israel and the Dead Sea area, and introduces the major challenges researchers face in the region. It also presents the first results of a new case study in Jordan, based on an analysis of peaty deposits located in the mountain slopes east of the Dead Sea. Such new studies help refine our knowledge of local environmental changes in the Southern Levant and especially the more arid areas, for which little information is presently available. More material suitable for palaeoenvironmental research, for example extensive tufa and travertine series, still awaits consideration in Jordan, opening up exciting perspectives for future research in the area. 相似文献
1000.
Huma Hameed Muhammad Farooq Cline Vuillier Claire Piquet-Pellorce Annaïg Hamon Marie-Thrse Dimanche-Boitrel Michel Samson Jacques Le Seyec 《International journal of molecular sciences》2022,23(13)
Some life-threatening acute hepatitis originates from drug-induced liver injury (DILI). Carbon tetrachloride (CCl4)-induced acute liver injury in mice is the widely used model of choice to study acute DILI, which pathogenesis involves a complex interplay of oxidative stress, necrosis, and apoptosis. Since the receptor interacting protein kinase-1 (RIPK1) is able to direct cell fate towards survival or death, it may potentially affect the pathological process of xenobiotic-induced liver damage. Two different mouse lines, either deficient for Ripk1 specifically in liver parenchymal cells (Ripk1LPC-KO) or for the kinase activity of RIPK1 (Ripk1K45A, kinase dead), plus their respective wild-type littermates (Ripk1fl/fl, Ripk1wt/wt), were exposed to single toxic doses of CCl4. This exposure led in similar injury in Ripk1K45A mice and their littermate controls. However, Ripk1LPC-KO mice developed more severe symptoms with massive hepatocyte apoptosis as compared to their littermate controls. A pretreatment with a TNF-α receptor decoy exacerbated liver apoptosis in both Ripk1fl/fl and Ripk1LPC-KO mice. Besides, a FasL antagonist promoted hepatocyte apoptosis in Ripk1fl/fl mice but reduced it in Ripk1LPC-KO mice. Thus, the scaffolding properties of RIPK1 protect hepatocytes from apoptosis during CCl4 intoxication. TNF-α and FasL emerged as factors promoting hepatocyte survival. These protective effects appeared to be independent of RIPK1, at least in part, for TNF-α, but dependent on RIPK1 for FasL. These new data complete the deciphering of the molecular mechanisms involved in DILI in the context of research on their prevention or cure. 相似文献