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91.
Chrystelle Le Danvic Gaelle Guiraudie-Capraz Djamel Abderrahmani Jean-Pierre Zanetta Patricia Nagnan-Le Meillour 《Journal of chemical ecology》2009,35(7):741-751
Knowledge of endogenous ligands of olfactory binding proteins is a prerequisite for studying their role in odor and pheromone
transduction. Here, we report the extraction, derivatization, and characterization by gas chromatography-mass spectrometry
of the natural ligands of pig, Sus scrofa (L.), Von Ebner’s Gland protein (VEG) and odorant binding protein (OBP). We identified two isoforms (VEG1 and VEG2), which
differed only by the linkage of an O-N-acetylglucosamine (O-GlcNac) group on VEG1. The natural ligands of VEG1 were characterized as two isomers of testosterone, whereas ligands of
VEG2 and OBP were fatty acids or their derivatives. Our findings suggest that the binding specificity of VEG1 for steroids
is governed by the presence of an O-GlcNac moiety on the protein. This specificity was confirmed by the binding of radiolabeled testosterone only by VEG1 in
an in-gel binding assay. This is the first evidence for a post-translational modification in the process of odorant discrimination
by olfactory binding proteins. 相似文献
92.
93.
Pierre Abel Pascal Gros Didier Loisel Cristina Russo Dos Santos Jean-Pierre Paris 《电信纪事》2000,55(3-4):131-142
In this paper we will present CyberNet, an interactive 3D dynamic information visualization tool designed to evaluate the added value this technology brings to network management. This paper explains how 3D metaphoric worlds may help the user and points out the problems raised by the dynamic nature of the information. It focuses on the solutions that were adopted to cope with these problems. We first present some prototypes of network administration tools implemented using the CyberNet framework. Secondly we explain how information is collected and structured, and then we show how this structured information may be mapped onto 3D graphical components in order to automatically build and update metaphoric 3D worlds. The last part of the paper presents the user interaction mechanisms provided by the system. 相似文献
94.
Charlotte Bernard Jean-Pierre Aimé Sophie Marsaudon Raphaël Levy Anne Marie Bonnot Cattien Nguyen Denis Mariolle François Bertin Amal Chabli 《Nanoscale research letters》2007,2(7):309-318
Evaporation of fluid at micro and nanometer scale may be used to self-assemble nanometre-sized particles in suspension. Evaporating
process can be used to gently control flow in micro and nanofluidics, thus providing a potential mean to design a fine pattern
onto a surface or to functionalize a nanoprobe tip. In this paper, we present an original experimental approach to explore
this open and rather virgin domain. We use an oscillating tip at an air liquid interface with a controlled dipping depth of
the tip within the range of the micrometer. Also, very small dipping depths of a few ten nanometers were achieved with multi
walls carbon nanotubes glued at the tip apex. The liquid is an aqueous solution of functionalized nanoparticles diluted in
water. Evaporation of water is the driving force determining the arrangement of nanoparticles on the tip. The results show
various nanoparticles deposition patterns, from which the deposits can be classified in two categories. The type of deposit
is shown to be strongly dependent on whether or not the triple line is pinned and of the peptide coating of the gold nanoparticle.
In order to assess the classification, companion dynamical studies of nanomeniscus and related dissipation processes involved
with thinning effects are presented. 相似文献
95.
96.
97.
Equilibrium stress-strain relationships in uniaxial extension for high cis-1,4-polyisoprene (Shell IR 307) networks were obtained by extrapolation of relaxation measurements to infinite time through a BKZ constitutive equation. Three series of networks were investigated, each series being characterized by its polymer precursor molecular weight. Influence of crosslinking density was studied through varying amounts of dicumyl peroxide as crosslinking agent. These results were used to test Flory and Erman's recent molecular elasticity theory of imperfect networks with constraints on junctions. It was shown that this later theory treating entanglements as restrictions on junction fluctuations could be reasonably used to characterize network topology. A universal value of 0.50 for the interpenetration parameter I is confirmed and an interpretation of parameter ζ in terms of network inhomogeneity is tentatively given. 相似文献
98.
James?M.?Ma Samad?A.?Firdosy Richard?B.?Kaner Jean-Pierre?Fleurial Vilupanur?A.?RaviEmail author 《Journal of Materials Science》2014,49(3):1150-1156
Lanthanum telluride (La3?x Te4) is a state-of-the-art n-type high temperature thermoelectric material that behaves as a weak and brittle ceramic. Vickers microindentation hardness testing was explored as a rapid analysis technique to characterize the mechanical properties of this material. An indentation size effect was observed with hardness values ranging from 439 ± 31 kgf/mm2 (0.01 kgf/10 s contact time) to 335 ± 6 kgf/mm2 (0.5 kgf/10 s contact time). The Vickers indentation fracture toughness, K VIF, based on measurements of crack lengths emanating from the corners of the Vickers indents was 0.70 ± 0.06 MPa m1/2. 相似文献
99.
Guillermo A. Oliveira Udry Laura Tiessler-Sala Eva Pugliese Agathe Urvoas Zakaria Halime Jean-Didier Marchal Jean-Pierre Mahy Rmy Ricoux 《International journal of molecular sciences》2022,23(23)
The covalent insertion of a cobalt heme into the cavity of an artificial protein named alpha Rep (αRep) leads to an artificial cobalt hemoprotein that is active as a catalyst not only for the photo-induced production of H2, but also for the reduction of CO2 in a neutral aqueous solution. This new artificial metalloenzyme has been purified and characterized by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS), circular dichroism, and UltraViolet–Visible spectroscopy. Using theoretical experiments, the structure of this biohybrid and the positioning of the residues near the metal complex were examined, which made it possible to complete the coordination of the cobalt ion by an axial glutamine Gln283 ligand. While the Co(III)–porphyrin catalyst alone showed weak catalytic activity for both reactions, 10 times more H2 and four times more CO2 were produced when the Co(III)–porphyrin complex was buried in the hydrophobic cavity of the protein. This study thus provides a solid basis for further improvement of these biohybrids using well-designed modifications of the second and outer coordination sphere by site-directed mutagenesis of the host protein. 相似文献
100.
We present a numerical study of a neural tree learning algorithm, the “triolearning≓ strategy. We study the behaviour of the
algorithm as a function of the size of the training set. The results show that a limited number of examples can be used to
estimate both the network performance and the network complexity that would result from running the algorithm on a large data
set. 相似文献