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51.
Alberto Bolognesi Paolo DiGianvincenzo Umberto Giovanella Raniero Mendichi Alberto Giacometti Schieroni 《European Polymer Journal》2008,44(3):793-800
The control of the organization of polymeric films from the nano- to the meso-scale is an ongoing field and different approaches have been proposed by many authors with the aim to drive the organization and the morphology of the materials to optimize their properties. One of the driving force of the organization at the micrometric and submicrometric scale is the degree of interaction between different polymeric chains and many successful examples of ordered supramolecular organization based on nano and microphase separation have been reported by using block copolymers and polymer blends. In this work we report on a synthetic approach to prepare a copolymeric structure formed by polystyrene and 3,4-ethylenedioxythiophene (EDOT) oligomers with the aim of preparing thin polymeric films exhibiting organized morphologies. 相似文献
52.
Simone Zanella Dr. Michele Mingozzi Alberto Dal Corso Dr. Roberto Fanelli Dr. Daniela Arosio Prof. Dr. Marco Cosentino Dr. Laura Schembri Dr. Franca Marino Dr. Marta De Zotti Prof. Dr. Fernando Formaggio Dr. Luca Pignataro Prof. Dr. Laura Belvisi Prof. Dr. Umberto Piarulli Prof. Dr. Cesare Gennari 《ChemistryOpen》2015,4(5):633-641
A dual-action ligand targeting both integrin αVβ3 and vascular endothelial growth factor receptors (VEGFRs), was synthesized via conjugation of a cyclic peptidomimetic αVβ3 Arg-Gly-Asp (RGD) ligand with a decapentapeptide. The latter was obtained from a known VEGFR antagonist by acetylation at the Lys13 side chain. Functionalization of the precursor ligands was carried out in solution and in the solid phase, affording two fragments: an alkyne VEGFR ligand and the azide integrin αVβ3 ligand, which were conjugated by click chemistry. Circular dichroism studies confirmed that both the RGD and VEGFR ligand portions of the dual-action compound substantially adopt the biologically active conformation. In vitro binding assays on isolated integrin αVβ3 and VEGFR-1 showed that the dual-action conjugate retains a good level of affinity for both its target receptors, although with one order of magnitude (10/20 times) decrease in potency. The dual-action ligand strongly inhibited the VEGF-induced morphogenesis in Human Umbilical Vein Endothelial Cells (HUVECs). Remarkably, its efficiency in preventing the formation of new blood vessels was similar to that of the original individual ligands, despite the worse affinity towards integrin αVβ3 and VEGFR-1. 相似文献
53.
A method for crack localization, based on so-called Local Modal Crack Sensitivity (LMCS), has recently been proposed by one of the Authors. As a major feature, the method only involves measuring eigenfrequencies. The method has already been used for beams of uniform cross section and homogeneous boundary conditions. In this paper, the method is extended to stepped beams, with both homogeneous and non-homogeneous boundary conditions. Experimental results confirm its usefulness for crack localization. Satisfactory localization of a second crack was also possible, so confirming the effectiveness of the method. 相似文献
54.
We present the detailed analysis of the diffusive transport of spatially inhomogeneous fluid mixtures and the interplay between structural and dynamical properties varying on the atomic scale. The present treatment is based on different areas of liquid state theory, namely, kinetic and density functional theory and their implementation as an effective numerical method via the lattice Boltzmann approach. By combining the first two methods, it is possible to obtain a closed set of kinetic equations for the singlet phase space distribution functions of each species. The interactions among particles are considered within a self-consistent approximation and the resulting effective molecular fields are analyzed. We focus on multispecies diffusion in systems with short-range hard-core repulsion between particles of unequal sizes and weak attractive long-range interactions. As a result, the attractive part of the potential does not contribute explicitly to viscosity but to diffusivity and the thermodynamic properties. Finally, we obtain a practical scheme to solve the kinetic equations by employing a discretization procedure derived from the lattice Boltzmann approach. Within this framework, we present numerical data concerning the mutual diffusion properties both in the case of a quiescent bulk fluid and shear flow inducing Taylor dispersion. 相似文献
55.
On the distribution of the (un)bounded sum of random variables 总被引:1,自引:0,他引:1
Umberto Cherubini 《Insurance: Mathematics and Economics》2011,48(1):56-63
We propose a general treatment of random variables aggregation accounting for the dependence among variables and bounded or unbounded support of their sum. The approach is based on the extension to the concept of convolution to dependent variables, involving copula functions. We show that some classes of copula functions (such as Marshall-Olkin and elliptical) cannot be used to represent the dependence structure of two variables whose sum is bounded, while Archimedean copulas can be applied only if the generator becomes linear beyond some point. As for the application, we study the problem of capital allocation between risks when the sum of losses is bounded. 相似文献
56.
Fuzzy ontology representation using OWL 2 总被引:3,自引:0,他引:3
Fernando Bobillo Umberto Straccia 《International Journal of Approximate Reasoning》2011,52(7):1073-1094
The need to deal with vague information in Semantic Web languages is rising in importance and, thus, calls for a standard way to represent such information. We may address this issue by either extending current Semantic Web languages to cope with vagueness, or by providing a procedure to represent such information within current standard languages and tools. In this work, we follow the latter approach, by identifying the syntactic differences that a fuzzy ontology language has to cope with, and by proposing a concrete methodology to represent fuzzy ontologies using OWL 2 annotation properties. We also report on some prototypical implementations: a plug-in to edit fuzzy ontologies using OWL 2 annotations and some parsers that translate fuzzy ontologies represented using our methodology into the languages supported by some reasoners. 相似文献
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60.
Problema di Dirichlet per l’equazione delle superfici di curvatura media assegnata con dato infinito
Umberto Massari 《Annali dell'Universita di Ferrara》1977,23(1):111-141
Riassunto In questo lavoro si studia il problema di Dirichlet per l’equazione delle superfici di curvatura media assegnata con dato
infinito. Si dimostra una condizione necessaria e sufficiente affinchè esista una soluzione. Si dimostra pure un teorema di
unicità.
Summary In this paper we consider the Dirichlet’s problem for surfaces of prescribed mean curvature with infinite data. We prove a necessary and sufficient condition for the existence of the solution. Finally we prove an uniqueness theorem.相似文献