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51.
Monica Borgatti Irene Mancini Nicoletta Bianchi Alessandra Guerrini Ilaria Lampronti Damiano Rossi Gianni Sacchetti Roberto Gambari 《BMC biochemistry》2011,12(1):15
Background
Cystic fibrosis (CF) airway pathology is a fatal, autosomal, recessive genetic disease characterized by extensive lung inflammation. After induction by TNF-α, elevated concentrations of several pro-inflammatory cytokines (i.e. IL-6, IL-1β) and chemokines (i.e. IL-8) are released from airway epithelial cells. In order to reduce the excessive inflammatory response in the airways of CF patients, new therapies have been developed and in this respect, medicinal plant extracts have been studied. In this article we have investigated the possible use of bergamot extracts (Citrus bergamia Risso) and their identified components to alter the expression of IL-8 associated with the cystic fibrosis airway pathology. 相似文献52.
Gianni Astarita M. E. Paulaitis R. G. Wissinger 《Journal of Polymer Science.Polymer Physics》1989,27(10):2105-2116
A thermodynamic analysis of the glass transition in polymers is presented, which predicts, with a minimum of assumptions, three of the four inequalities which have consistently been observed experimentally: i.e., that specific heat and isothermal compressibility of the glass are lower than those of the rubber, and that the Prigogine-Defay ratio is larger than unity. The analysis cannot predict the fact that the thermal expansion coefficient of the glass is also lower than that of the rubber, and indeed the converse situation is not a thermodynamic impossibility. 相似文献
53.
We investigate entire radial solutions of the semilinear biharmonic equation Δ2u=λexp(u) in Rn, n?5, λ>0 being a parameter. We show that singular radial solutions of the corresponding Dirichlet problem in the unit ball cannot be extended as solutions of the equation to the whole of Rn. In particular, they cannot be expanded as power series in the natural variable s=log|x|. Next, we prove the existence of infinitely many entire regular radial solutions. They all diverge to −∞ as |x|→∞ and we specify their asymptotic behaviour. As in the case with power-type nonlinearities [F. Gazzola, H.-Ch. Grunau, Radial entire solutions for supercritical biharmonic equations, Math. Ann. 334 (2006) 905-936], the entire singular solution x?−4log|x| plays the role of a separatrix in the bifurcation picture. Finally, a technique for the computer assisted study of a broad class of equations is developed. It is applied to obtain a computer assisted proof of the underlying dynamical behaviour for the bifurcation diagram of a corresponding autonomous system of ODEs, in the case n=5. 相似文献
54.
Gianni Nicoletto 《Optics and Lasers in Engineering》1990,12(2-3)
The local deformation about fatigue cracks has been investigated by the coherent optics method of moiré interferometry. The complexity of the interference fringe patterns motivated the parallel development of companion numerical models for simulating moiré interferometric response for known boundary conditions. Experimental patterns are here examined in the light of computer-generated fringe systems for a stationary crack in elastic as well as elastic-plastic solids. Various effects due to material plasticity, specimen-dependent non-singular stress, and mixed mode loading are identified in the fringe patterns. 相似文献
55.
The Szpilrajn theorem and its strengthening by Dushnik and Miller belong to the most quoted theorems in many fields of pure
and applied mathematics as, for instance, order theory, mathematical logic, computer sciences, mathematical social sciences,
mathematical economics, computability theory and fuzzy mathematics. The Szpilrajn theorem states that every partial order
can be refined or extended to a total (linear) order. The theorem by Dushnik and Miller states, moreover, that every partial
order is the intersection of its total (linear) refinements or extensions. Since in mathematical social sciences or, more
general, in any theory that combines the concepts of topology and order one is mainly interested in continuous total orders
or preorders in this paper some aspects of a possible continuous analogue of the Szpilrajn theorem and its strengthening by
Dushnik and Miller will be discussed. In particular, necessary and sufficient conditions for a topological space to satisfy
a possible continuous analogue of the Dushnik-Miller theorem will be presented. In addition, it will be proved that a continuous
analogue of the Szpilrajn theorem does not hold in general. Further, necessary and in some cases necessary and sufficient
conditions for a topological space to satisfy a possible continuous analogue of the Szpilrajn theorem will be presented.
相似文献
56.
The fundamental solution of the fractional diffusion equation of distributed order in time (usually adopted for modelling sub-diffusion processes) is obtained based on its Mellin–Barnes integral representation. Such solution is proved to be related via a Laplace-type integral to the Fox–Wright functions. A series expansion is also provided in order to point out the distribution of time-scales related to the distribution of the fractional orders. The results of the time fractional diffusion equation of a single order are also recalled and then re-obtained from the general theory. 相似文献
57.
Chiara Dall'asta Gianluigi Ingletto Roberto Corradini Gianni Galaverna Rosangela Marchelli 《Journal of inclusion phenomena and macrocyclic chemistry》2003,45(3-4):257-263
Cyclodextrins have been used as fluorescence enhancers in HPLC to improve thedetection limits of aflatoxins, cancerogens which can be found in severalfoodstuffs. In this work, a screening of several cyclodextrins has been performedin order to find the factors affecting the fluorescence enhancement. Evidence for formationof a 1 : 1 AF-CD inclusion complex has been achieved by titration and competitiveexperiments with adamantanecarboxylic acid and by fluorescence quenching by KI.Stability constants of the AF-CD complexes were evaluated. 相似文献
58.
Moiré interferometry is a valuable tool for investigations of the mechanics of materials. It is characterized by high-sensitivity and full-field capability. In this paper, the applicability of moiré interferometry and microscopic magnification to the visualization of the heterogeneous nature of the plastic strains in a polycrystalline material is considered. Plastic deformation of a coarse-grained aluminum is considered in detail. 相似文献
59.
60.
Several variants of the modal interpretation of quantum mechanics have been introduced and discussed in recent years. In this paper we present a study of the mathematical foundations of such an interpretation in the framework of the quantum theory of measurement. 相似文献