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151.
We study the frequency polygon investigated by Scott (J Am Stat Assoc 80: 348–354, 1985) as a nonparametric density estimate for a continuous and stationary real random field \({\left( X_{\mathbf{t}},\mathbf{t}\in\mathbb{R}^{N}\right)}\). We establish the asymptotic expressions for the integrated pointwise squared bias and the integrated pointwise squared variance of the estimate when the field is observed over a rectangular domain of \({\mathbb{R}^{N}}\). Under mild mixing conditions, we show that the estimate achieves the same rate of convergence to zero of the integrated mean squared error as kernel estimators and it can also attain the optimal uniform strong rate of convergence \({\left(\widehat{\mathbf{T}}^{-1} \log \widehat{\mathbf{T}}\right)^{1/3}}\) for appropriate choices of the bin widths. 相似文献
152.
153.
154.
Some new examples of recurrence and non-recurrence sets for products of rotations on the unit circle
We study recurrence and non-recurrence sets for dynamical systems on compact spaces, in particular for products of rotations on the unit circle T. A set of integers is called r-Bohr if it is recurrent for all products of r rotations on T, and Bohr if it is recurrent for all products of rotations on T. It is a result due to Katznelson that for each r ? 1 there exist sets of integers which are r-Bohr but not (r+1)-Bohr. We present new examples of r-Bohr sets which are not Bohr, thanks to a construction which is both flexible and completely explicit. Our results are related to an old combinatorial problem of Veech concerning syndetic sets and the Bohr topology on ?, and its reformulation in terms of recurrence sets which is due to Glasner and Weiss. 相似文献
155.
Sophie Laruelle Charles-Albert Lehalle Gilles Pagès 《Mathematics and Financial Economics》2013,7(3):359-403
We model a trader interacting with a continuous market as an iterative algorithm that adjusts limit prices at a given rhythm and propose a procedure to minimize trading costs. We prove the $a.s.$ convergence of the algorithm under assumptions on the cost function and give some practical criteria on model parameters to ensure that the conditions to use the algorithm are met (notably, using the co-monotony principle). We illustrate our results with numerical experiments on both simulated and market data. 相似文献
156.
Darbandi Masih Laurent Sophie Busch Martin Li Zi-An Yuan Ying Krüger Michael Farle Michael Winterer Markus Vander Elst Luce Muller Robert N. Wende Heiko 《Journal of nanoparticle research》2013,15(5):1-9
Quasi-critical fluctuations occur close to critical points or close to continuous phase transitions. In three-dimensional systems, precision tuning is required to access the fluctuation regime. Lowering the dimensionality enhances the parameter space for quasi-critical fluctuations considerably. This enables one to make use of novel properties emerging in fluctuating systems, such as giant susceptibilities, Casimir forces or novel quasi-particle interactions. Examples are discussed ranging from simple metal–adsorbate systems to unconventional superconductivity in iron-based superconductors. 相似文献
157.
Alberto Palazzolo Sophie Feuillastre Viktor Pfeifer Sbastien Garcia‐Argote Donia Bouzouita Simon Tricard Cline Chollet Elodie Marcon David‐Alexandre Buisson Sophie Cholet Franois Fenaille Guy Lippens Bruno Chaudret Grgory Pieters 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(15):4945-4949
A general approach for the efficient hydrogen‐isotope exchange of nucleobase derivatives is described. Catalyzed by ruthenium nanoparticles, using mild reaction conditions, and involving either D2 or T2 as isotopic sources, this reaction possesses a wide substrate scope and a high solvent tolerability. This novel method facilitates the access to essential diagnostic tools in drug discovery and development: tritiated pharmaceuticals with high specific activities and deuterated oligonucleotides suitable for use as internal standards during LC‐MS quantification. 相似文献
158.
Billon Sophie Sardini Paul Leblond Sylvain Fichet Pascal 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(3):699-709
Journal of Radioanalytical and Nuclear Chemistry - A large set of key parameters is provided to use in decommissioning operations, the conversion method fully described in the companion paper... 相似文献
159.
Dr. Margot N. Wenzel Dr. Riccardo Bonsignore Sophie R. Thomas Dr. Didier Bourissou Prof. Giampaolo Barone Prof. Angela Casini 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(32):7628-7634
With the aim of exploiting the use of organometallic species for the efficient modification of proteins through C-atom transfer, the gold-mediated cysteine arylation through a reductive elimination process occurring from the reaction of cyclometalated AuIII C^N complexes with a zinc finger peptide (Cys2His2 type) is here reported. Among the four selected AuIII cyclometalated compounds, the [Au(CCON)Cl2] complex featuring the 2-benzoylpyridine (CCON) scaffold was identified as the most prone to reductive elimination and Cys arylation in buffered aqueous solution (pH 7.4) at 37 °C by high-resolution LC electrospray ionization mass spectrometry. DFT and quantum mechanics/molecular mechanics (QM/MM) studies permitted to propose a mechanism for the title reaction that is in line with the experimental results. Overall, the results provide new insights into the reactivity of cytotoxic organogold compounds with biologically important zinc finger domains and identify initial structure–activity relationships to enable AuIII-catalyzed reductive elimination in aqueous media. 相似文献
160.
Khaled Beyaz Carlos Vaca-Garcia Emeline Vedrenne Nabila Haddadine Ahmed Benaboura Sophie Thiebaud-Roux 《International Journal of Polymer Analysis and Characterization》2019,24(3):245-256
In this work, we reported the preparation of a novel biomaterial, by graft-polymerization of 2-2-dimethyl-1-3-dioxolan-4-yl methyl acrylate (solketalacrylate, DMDMA) on hydroxyethyl cellulose (HEC) using KPS as initiator. Several experiments were performed to found the optimum conditions for the preparation of this biopolymer, by varying the time of the reaction as well as the initiator and the monomer ratio. Results showed that the highest grafting yield was 25%, obtained after 72?minutes at 65?°C, using THF as solvent. The structure of the grafted copolymer was confirmed by X-ray diffraction patterns which showed, besides the characteristic peaks of HEC at 2θ?=?31.74° and 44.63° a new peak at 2θ?=?30.72° related to an organized structure of the grafted polymer on the HEC backbone. The DSC analysis showed a single glass transition temperature Tg, intermediate between the corresponding values for HEC and neat poly(solketal acrylate). Moreover, the grafted biomaterial presented two-fold more moisture absorption ability by comparison with HEC, making this new synthetic biomaterial highly promising for dryness applications. In our knowledge, the synthesized monomer: 2-2-dimethyl-1-3-dioxolan-4-yl methyl acrylate, (solketal acrylate, DMDMA), has never been grafted on the HEC backbones before that is what makes the novelty of the present work. 相似文献