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1.
Results in Mathematics - First asymptotic relations of Voronovskaya-type for rational operators of Shepard-type are shown. A positive answer in some senses to a problem on the pointwise... 相似文献
2.
G. Ciasca M. Chiarpotto G. Campi B. Bocca M. Rodio A. Pino A. Ricci N. Poccia C. Rossi A. Alimonti H. Amenitsch P. De Sole A. Bianconi 《Journal of nanoparticle research》2011,13(11):6149-6155
This study investigates the uptake of iron and aluminium by apoferritin. In particular, we provide the first evidence that apoferritin is able to bind in vitro the physiological form of aluminium, Al(OH)4 ?, to reach an Al/Fe atomic ratio of about 0.15. Mass spectrometry analysis shows that the Al content increases linearly as a function of Al concentration in solution. These findings provide a better understanding of the Al uptake in vivo, confirming that the metal content of ferritin depends on the metal bio-availability. 相似文献
3.
Veronica M. T. Lattanzio Biancamaria Ciasca Miriam Haidukowski Alessandro Infantino Angelo Visconti Michelangelo Pascale 《Journal of mass spectrometry : JMS》2013,48(12):1291-1298
Fusarium langsethiae, formally described as a new species over a decade ago, has been identified as the main producer of HT‐2 (HT2) and T‐2 (T2) toxins in Europe in small cereal grains. Mycotoxin contamination caused by this Fusarium species can represent a food safety hazard that deserves further attention. In the present work, the mycotoxin profile in wheat cultures of F. langsethiae is presented with particular reference to the production of major type‐A trichothecenes and their glucosyl derivatives. F. langsethiae isolates, representative of the major Italian wheat cultivation areas, were tested for the production of T2, HT2, diacetoxyscirpenol (DAS) and neosolaniol (NEO), and relevant glucosyl derivatives. Liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) was used for the identification and chemical characterization of these metabolites. F. langsethiae isolates under investigation resulted to be potent producers of T2, HT2 and NEO. Furthermore, a well‐defined set of isolates, all originating from Central Italy, produced also DAS. All isolates were found to be able to produce HT2 glucosyl derivatives, whereas only traces of T2 glucoside were detected in one sample. Furthermore, two mono‐glucosyl derivatives of NEO and one mono‐glucoside derivative of DAS were identified and characterized. The screening for the presence/absence of glucosylated trichothecenes in analyzed fungal extracts revealed a general co‐occurrence of these derivatives with the parent toxin at levels that could be roughly estimated to account up to 37% of the relevant unconjugated toxin. This is the first report of the production of glucosylated trichothecenes by F. langsethiae cultured on small grains. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
4.
A Combined NMR and Computational Approach to Determine the RGDechi‐hCit‐αvβ3 Integrin Recognition Mode in Isolated Cell Membranes 下载免费PDF全文
Dr. Biancamaria Farina Dr. Ivan de Paola Dr. Luigi Russo Dr. Domenica Capasso Dr. Annamaria Liguoro Dr. Annarita Del Gatto Dr. Michele Saviano Prof. Paolo V. Pedone Dr. Sonia Di Gaetano Dr. Gaetano Malgieri Dr. Laura Zaccaro Prof. Roberto Fattorusso 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):681-693
The critical role of integrins in tumor progression and metastasis has stimulated intense efforts to identify pharmacological agents that can modulate integrin function. In recent years, αvβ3 and αvβ5 integrin antagonists were demonstrated to be effective in blocking tumor progression. RGDechi‐hCit, a chimeric peptide containing a cyclic RGD motif linked to an echistatin C‐terminal fragment, is able to recognize selectively αvβ3 integrin both in vitro and in vivo. High‐resolution molecular details of the selective αvβ3 recognition of the peptide are certainly required, nonetheless RGDechi‐hCit internalization limited the use of classical in cell NMR experiments. To overcome such limitations, we used WM266 isolated cellular membranes to accomplish a detailed NMR interaction study that, combined with a computational analysis, provides significant structural insights into αvβ3 molecular recognition by RGDechi‐hCit. Remarkably, on the basis of the identified molecular determinants, we design a RGDechi‐hCit mutant that is selective for αvβ5 integrin. 相似文献
5.
Biancamaria Della Vecchia Giuseppe Mastroianni József Szabados 《Acta Mathematica Hungarica》2004,103(1-2):19-41
We give direct and converse results for the weighted approximation of functions with endpoint or inner singularities by Bernstein operators. 相似文献
6.
Biancamaria Della Vecchia 《Results in Mathematics》2003,43(1-2):79-87
The author constructs rational operators for the weighted uniform approximation of functions with endpoints singularities by algebraic weights in [?1,1]. New direct and converse results not possible by polynomials are proved. 相似文献
7.
G Ciasca G Campi A Battisti G Rea M Rodio M Papi P Pernot A Tenenbaum A Bianconi 《Langmuir : the ACS journal of surfaces and colloids》2012,28(37):13405-13410
The tau protein belongs to the category of Intrinsically Disordered Proteins (IDP), which in their native state lack a folded structure and fluctuate between many conformations. In its physiological state, tau helps nucleating and stabilizing the microtubules' (MTs) surfaces in the axons of the neurons. Tau is mainly composed by two domains: (i) the binding domain that tightly bounds the MT surfaces and (ii) the projection domain that exerts a long-range entropic repulsive force and thus provides the proper spacing between adjacent MTs. Tau is also involved in the genesis and in the development of the Alzheimer disease when it detaches from MT surfaces and aggregates in paired helical filaments. Unfortunately, the molecular mechanisms behind these phenomena are still unclear. Temperature variation, rarely considered in biological studies, is here used to provide structural information on tau correlated to its role as an entropic spacer between adjacent MTs surfaces. In this paper, by means of small-angle X-ray scattering and molecular dynamics simulation, we demonstrate that tau undergoes a counterintuitive collapse phenomenon with increasing temperature. A detailed analysis of our results, performed by the Ensemble Optimization Method, shows that the thermal collapse is coupled to the occurrence of a transient long-range contact between a region encompassing the end of the proline-rich domain P2 and the first part of the repeats domain, and the region of the N-terminal domain entailing residues 80-150. Interestingly these two regions involved in the tau temperature collapse belong to the flexible projection domain that acts as an entropic bristle and regulates the MTs' architecture. Our results show that temperature is an important parameter that influences the dynamics of the tau projection domain, and hence its entropic behavior. 相似文献
8.
Biancamaria Della Vecchia Giuseppe Mastroianni József Szabados 《Mediterranean Journal of Mathematics》2013,10(1):1-15
In [1], we have introduced a new weighted type of modification of the classical Kantorovich operator. The advantage of this operator is that there is no restriction on the parameters of the weight, and the class of functions is wider than in the earlier version of the weighted operator (cf. the monograph of Ditzian and Totik [3]). Direct and converse theorems and a Voronovskaya-type relation were proved. Here we solve the saturation problem of the operator (Theorem 2.1). We follow the method developed in [3], but the details are much more involved. A surprising fact emerges in determining the trivial class of saturation (Theorem 3.1). 相似文献
9.
We give error estimates for the weighted approximation of functions on the real line with Freud-type weights, by entire functions interpolating at finitely or infinitely many points on the real line. The error estimates involve weighted moduli of continuity corresponding to general Freud-type weights for which the density of polynomials is not always guaranteed. 相似文献
10.
Biancamaria Della Vecchia Giuseppe Mastroianni Pter Vrtesi 《Journal of Computational and Applied Mathematics》1994,50(1-3):233-240
The authors consider a procedure of Hermite interpolation of higher order based on the zeros of Jacobi polynomials plus the endpoints ±1 and prove that such a procedure can always well approximate a function and its derivatives simultaneously in uniform norm. 相似文献