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101.
John K. Meissen Matthew D. Sweeney Matthew Girardi Roger Lawrence Jeffrey D. Esko Julie A. Leary 《Journal of the American Society for Mass Spectrometry》2009,20(4):652-657
The presence of 3-O-sulfated glucosamine residues in heparin or heparan sulfate plays a role in binding to antithrombin III
and HSV infection. In this study, tandem mass spectrometry was used to differentiate between two heparin disaccharide isomers
containing variable sulfate at C6 in a common disaccharide and C3 in a more rare one. The dissociation patterns shown by MS2 and MS3 were clearly distinguishable between the isomers, allowing their differentiation and quantitation. Using this technique,
we show that an octasaccharide with 11 sulfate groups with high affinity for inflammatory chemokine CCL2 does not contain
3-O-sulfated disaccharides. 相似文献
102.
Qinglan Xia 《Journal of Geometric Analysis》2009,19(2):452-479
In this article, we study the geodesic problem in a generalized metric space, in which the distance function satisfies a relaxed
triangle inequality d(x,y)≤σ(d(x,z)+d(z,y)) for some constant σ≥1, rather than the usual triangle inequality. Such a space is called a quasimetric space. We show that many well-known results
in metric spaces (e.g. Ascoli-Arzelà theorem) still hold in quasimetric spaces. Moreover, we explore conditions under which
a quasimetric will induce an intrinsic metric. As an example, we introduce a family of quasimetrics on the space of atomic
probability measures. The associated intrinsic metrics induced by these quasimetrics coincide with the d
α
metric studied early in the study of branching structures arisen in ramified optimal transportation. An optimal transport
path between two atomic probability measures typically has a “tree shaped” branching structure. Here, we show that these optimal
transport paths turn out to be geodesics in these intrinsic metric spaces.
This work is supported by an NSF grant DMS-0710714. 相似文献
103.
George G. Roussas Debasis Bhattacharya 《Statistical Inference for Stochastic Processes》2009,12(2):185-201
Under suitable regularity conditions imposed on a general discrete time-parameter stochastic process, the Hájek-Inagaki convolution
representation theorem is established for randomly stopped locally asymptotically mixed normal experiments.
D. Bhattacharya: On leave from Visva-Bharati University, Santiniketan, India. 相似文献
104.
The Pb doped metastable tetragonal ZrO2 (t-ZrO2:Pb) nanoparticles have been successfully synthesized by hydrothermal method. Pb ion doping has great effects on the phases, crystallite sizes and optical band gaps. Systematic structural characterization revealed that the introduction of Pb ion results in lattice expansion. The as-prepared t-ZrO2:Pb with ca 4–6 nm in size has high specific surface area (>150 m2/g) and narrow particle size distributions. The diffuse reflectance spectra investigated that the band gap shifts from ultraviolet (Eg = 5.19 eV) for pure ZrO2 to the visible region for t-ZrO2:Pb and the gap can be effectively adjusted with the content of Pb in nanocrystals. Through thermal treatment, Pb ion doped in ZrO2 crystals was excluded with increasing temperature. At 800 °C, the three t-ZrO2:Pb samples of ZPO-2, ZPO-3 and ZPO-4 still contained the pure tetragonal phase, in which Pb content were not reduced to zero, while the transformation from tetragonal to monoclinic phase occurred due to zero Pb content in ZPO-1. The reason to this transformation and stabilized mechanism of Pb ion in ZrO2 were discussed. 相似文献
105.
106.
V.K. Sharma S. Mitra P. Maheshwari D. Dutta P.K. Pujari R. Mukhopadhyay 《The European physical journal. Special topics》2010,189(1):273-277
Dynamics of ethylene glycol (EG) adsorbed in H-ZSM5 zeolite as studied using quasielastic neutron scattering (QENS) technique
is reported here. Analysis of QENS data revealed that observed dynamics correspond to isotropic rotational motion of EG. Rotational
diffusion coefficient of EG adsorbed in H-ZSM5 zeolite is found to be slower compared to bulk and comparable to that of benzene
adsorbed in the same host. Positron Annihilation Spectroscopy (PAS) technique is used to understand the nature of guest-host
interaction and the results of both QENS and PAS are found to be consistent with each other. 相似文献
107.
108.
The effects of bath composition and deposition variables on the electrodeposition of Zn–Ni–P alloys were studied in order to develop a single bath for deposition of Ni–P/Zn–Ni compositionally modulated multilayer coatings (CMMCs). The basis for development of the bath was a large increase in the Ni deposition rate compared to that of Zn at low deposition overpotentials combined with the impossibility of codeposition of Zn with P. EDS analysis demonstrated that the deposits obtained from the Zn–Ni–P bath at low overpotentials were practically all Ni–P, while the alloy deposited at high overpotentials was mainly Zn–Ni with around 3.2 wt% P content. 相似文献
109.
The composition, structure, substructure, and physicomechanical properties of hafnium diboride films deposited by nonreactive
rf magnetron sputtering are studied by X-ray diffraction (including photographic recording) and electron microscopy. The results
obtained are analyzed, and the film growth kinetics is revealed. 相似文献
110.
Thiago Fassarella 《Bulletin of the Brazilian Mathematical Society》2011,42(2):321-330
We show that if a Laurent polynomial on the coordinate ring of the complex algebraic torus on n variables has vanishing logarithmic Hessian, then up to an automorphism of the torus, the Laurent polynomial depends on at
most n−1 variables. 相似文献