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91.
Background
Stargazin (γ2) and the closely related γ3, and γ4 transmembrane proteins are part of a family of proteins that may act as both neuronal voltage-dependent calcium channel (VDCC) γ subunits and transmembrane α-amino-3-hydroxy-5-methyl-4-isoxazoleproponinc (AMPA) receptor regulatory proteins (TARPs). In this investigation, we examined the distribution patterns of the stargazin-like proteins γ2, γ3, and γ4 in the human central nervous system (CNS). In addition, we investigated whether human γ2 or γ4 could modulate the electrophysiological properties of a neuronal VDCC complex transiently expressed in Xenopus oocytes. 相似文献92.
U. Kürpick G. Meister A. Goldmann 《Applied Physics A: Materials Science & Processing》1992,55(6):529-532
The reaction of atomic hydrogen (or atomic deuterium) with highly orientated pyrolytic graphite surfaces has been studied by means of thermal desorption spectroscopy. In some cases atomic deuterium instead of atomic hydrogen, was used solely to assign the desorbed masses unambiguously to the different hydrocarbons. The desorption of D2 and fourteen hydrocarbons was observed. D2 desorbed at higher temperatures than the CH-(CD) compounds, the desorption spectra of the hydrocarbons contained two peaks. The dependence of the desorption spectra of several hydrocarbons on the heating rate, the atomic hydrogen exposure and the composition of the desorption products was investigated in detail. The kinetic parameters of the desorption process were determined for CH, C2H2, and CD4. The spectra showed that there must be a first order desorption process for all the hydrocarbons, the values for the activation energy and the frequency factor were the same within experimental errors. The results were discussed by means of a simple model. 相似文献
93.
Annette A’Campo–Neuen 《Archiv der Mathematik》2006,87(3):217-226
We prove tight lower bounds for the coefficients of the toric h-vector of an arbitrary centrally symmetric polytope generalizing previous results due to R. Stanley and the author using
toric varieties. Our proof here is based on the theory of combinatorial intersection cohomology for normal fans of polytopes
developed by G. Barthel, J.-P. Brasselet, K. Fieseler and L. Kaup, and independently by P. Bressler and V. Lunts. This theory
is also valid for nonrational polytopes when there is no standard correspondence with toric varieties. In this way we can
establish our bounds for centrally symmetric polytopes even without requiring them to be rational.
Received: 24 March 2004 相似文献
94.
Dr. Thomas Lunkenbein Dr. Frank Girgsdies Anna Wernbacher Dr. Johannes Noack Dr. Gudrun Auffermann Akira Yasuhara Achim Klein‐Hoffmann Prof. Wataru Ueda Dr. Maik Eichelbaum Dr. Annette Trunschke Prof. Robert Schlögl Dr. Marc G. Willinger 《Angewandte Chemie (International ed. in English)》2015,54(23):6828-6831
Complex Mo,V‐based mixed oxides that crystallize in the orthorhombic M1‐type structure are promising candidates for the selective oxidation of small alkanes. The oxygen sublattice of such a complex oxide has been studied by annular bright field scanning transmission electron microscopy. The recorded micrographs directly display the local distortion in the metal oxygen octahedra. From the degree of distortion we are able to draw conclusions on the distribution of oxidation states in the cation columns at different sites. The results are supported by X‐ray diffraction and electron paramagnetic resonance measurements that provide integral details about the crystal structure and spin coupling, respectively. 相似文献
95.
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98.
Druart C Delhomme O de Vaufleury A Ntcho E Millet M 《Analytical and bioanalytical chemistry》2011,399(4):1725-1732
Analysing herbicides in soil is a complex issue that needs validation and optimization of existing methods. An extraction and analysis method was developed to assess concentrations of glyphosate, glufosinate and aminomethylphophonic acid (AMPA) in field soil samples. After testing extractions by accelerated solvent extraction and ultrasonic extraction, agitation was selected with the best recoveries. Water was preferred as solvent extraction because it resulted in a cleaner chromatogram with fewer impurities than was the case with alkaline solvents. Analysis was performed by FMOC pre-column derivatization followed by high-performance liquid chromatography (HPLC) on a 300 mm C(18) column which permitted enhanced separation and sensitivity than a 250 mm C(18) column and increased resistance than the NH(2) column for soil samples. This extraction and analysis method allowing a minimum of steps before the injection in the HPLC with fluorescence detection is efficient and sensitive for a clay-loamy soil with detection limits of 103 μg kg(-1) for glyphosate, 15 μg kg(-1) for glufosinate and 16 μg kg(-1) for AMPA in soil samples. 相似文献
99.
García F Less RJ McPartlin M Michalski A Mulvey RE Naseri V Stead ML Morán de Vega A Wright DS 《Chemical communications (Cambridge, England)》2011,47(6):1821-1823
The structures of a series of spherical host-guest complexes [{MeE(PPh)(3)Li(4)·3thf}(4)(μ(4)-X)](-) (E = Al, [1X](-); E = Ga, [2X](-); E = In, [3X](-)) reveal that changing the halide ions (X = Cl, Br, or I) within their central tetrahedral Li(4) sites has negligible effect on the structural parameters. 相似文献
100.
Allison Talley Annette F. Kelley Marcus R. Bond 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(12):m395-m399
The title compound, {(C3H10N)4[Ni3Cl10]}n, contains zigzag layers of tri‐μ‐chlorido‐bridged linear 2/m‐symmetric Ni3Cl12 segments, linked by mono‐μ‐chlorido quasi‐linear bridges to two other segments at each end. These inorganic layers are interleaved with interdigitated bilayers of mirror‐symmetric n‐propylammonium cations, the ammonium head groups of which are directed into the inorganic layers to form multiple N—H...Cl hydrogen bonds, while the propyl tail groups pack together in a tongue‐and‐groove manner in the center of the bilayer. The propyl groups are ordered at 100 K but disordered with opposite conformations on the mirror plane at 240 K. 相似文献