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41.
42.
Lorella Guadagnini Elisabetta Salatelli Anastasiia Kharina Domenica Tonelli 《Journal of Solid State Electrochemistry》2014,18(10):2731-2742
A composite material based on overlapped layers of electrochemically synthesized Prussian Blue (PB) and terthiophene-derived polymer is described, aiming at enhancing the stability of the hexacyanoferrate thanks to the protective action of the polymer. Two bilayer configurations and deposition methods (for the polymer component) were tested. The morphology and electrochemical behavior in organic solvent and in aqueous solutions containing different supporting electrolytes were carried out. The best performances of electrodes modified with films of the composite material as to increased stability of PB were achieved with the potentiostatically deposited polymer covering the PB layer, in acetate buffer at pH 5.5. As for potential cycling stress, the anodic and cathodic peak currents due to PB were not decreased after 20 cycles. Conversely, PB alone displayed the anodic peak currents relevant to PB/Prussian White (PW) and PB/Berlin Green (BG) systems decreased by about 30 %. The stability to local pH increase was assessed by cyclic voltammetry after electrochemical reduction of H2O2. For example, the anodic peak currents were decreasing by 15 % and 5 % for the two PB redox systems, while for PB alone the same currents decreased by 35 % and 10 %. The response sensitivity to hydrogen peroxide was improved by 54 %, with respect to PB alone, as evaluated by chronoamperometry. 相似文献
43.
Exploring Weak Ligand–Protein Interactions by Long‐Lived NMR States: Improved Contrast in Fragment‐Based Drug Screening
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Roberto Buratto Daniele Mammoli Dr. Elisabetta Chiarparin Dr. Glyn Williams Prof. Geoffrey Bodenhausen 《Angewandte Chemie (International ed. in English)》2014,53(42):11376-11380
Ligands that have an affinity for protein targets can be screened very effectively by exploiting favorable properties of long‐lived states (LLS) in NMR spectroscopy. In this work, we describe the use of LLS for competitive binding experiments to measure accurate dissociation constants of fragments that bind weakly to the ATP binding site of the N‐terminal ATPase domain of heat shock protein 90 (Hsp90), a therapeutic target for cancer treatment. The LLS approach allows one to characterize ligands with an exceptionally wide range of affinities, since it can be used for ligand concentrations [L] that are several orders of magnitude smaller than the dissociation constants KD. This property makes the LLS method particularly attractive for the initial steps of fragment‐based drug screening, where small molecular fragments that bind weakly to a target protein must be identified, which is a difficult task for many other biophysical methods. 相似文献
44.
Paolo Ferruti Elisabetta Ranucci Amedea Manfredi Nicolò Mauro Elena Ferrari Riccardo Bruni Francesco Colombo Patrizia Mussini Manuela Rossi 《Journal of polymer science. Part A, Polymer chemistry》2012,50(24):5000-5010
Traditional precipitation methods for inorganic micropollutant removal from waters are increasingly being replaced by sorption methods based on both natural and synthetic materials. In this context, two novel effective heavy metal ions absorbers are presented. These resins, LYMA and LMT85, were crosslinked poly(amidoamine)s carrying amine and carboxyl groups in their repeating units. In particular, the LYMA‐repeating unit contains one carboxyl and two amine groups and is a mimic of L ‐lysine, whereas LMT85 contains two amine and five carboxyl groups and is a mimic of EDTA. Both resins were prepared at moderate cost by simple eco‐friendly procedures. The heavy metal ion set adopted as benchmark was Cu2+, Cd2+, Pb2+, Zn2+, Ni2+, and Co2+. LYMA proved selective for Cu2+ and Ni2+, the other ions tested being negligibly absorbed, whereas LMT85 proved capable of rapidly and quantitatively absorbing all the ions tested either singly or in mixed solution. The absorption process was reversible, and the resins were easily regenerated by acidification. The absorption of several metal ions imparted intense coloring to the resins, a feature possibly exploitable for analytical purposes. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
45.
Elisabetta Fersini E. Messina F. Archetti C. Manfredotti 《Journal of Mathematical Modelling and Algorithms》2010,9(3):275-289
The combined analysis of tissue micro array and drug response datasets has the potential of revealing valuable knowledge about
various relations among gene expressions and drug activity patterns in tumor cells. However, the amount and the complexity
of biological data needs appropriate data mining models in order to extract interesting patterns and useful information. The
ultimate goal of this paper is to define a model which, given the gene expression profile related to a specific tumor tissue,
could help in selecting a set of most responsive drugs. This is accomplished through an integrated framework based on a constraint-based
clustering algorithm, called Relational K-Means, which groups cell lines using drug response information and taking into account
cell-to-cell relationships derived from their gene expression profiles. 相似文献
46.
Drag reduction by polymers in wall turbulence is bounded from above by a universal maximal drag reduction (MDR) velocity profile that is a log law, estimated experimentally by Virk as V+(y+) approximately 11.7logy+ - 17. Here V+(y+) and y+ are the mean streamwise velocity and the distance from the wall in "wall" units. In this Letter we propose that this MDR profile is an edge solution of the Navier-Stokes equations (with an effective viscosity profile) beyond which no turbulent solutions exist. This insight rationalizes the universality of the MDR and provides a maximum principle which allows an ab initio calculation of the parameters in this law without any viscoelastic experimental input. 相似文献
47.
Maria Giorgia Cutrufello Italo Ferino Elisabetta Rombi Vincenzo Solinas Gerardo Colón José Antonio Navío 《Reaction Kinetics and Catalysis Letters》2003,79(1):93-99
A ceria-lanthana catalytic system prepared by the sol-gel technique proved to be active in 4-methylpentan-2-ol conversion,
mainly leading to 4-methylpent-1-ene, a monomer for manufacturing polymers of high technological properties. The product distribution
strongly depends on the acid-base features of the catalyst. The catalytic behavior of the samples was examined in the light
of their acid-base properties.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
48.
We study a class of degenerate elliptic second order differential operators acting on some polynomial weighted function spaces on [0,+[. We show that these operators are the generators of C
0-semigroups of positive operators which, in turn, are the transition semigroups associated with right-continuous normal Markov processes with state space [0,+]. Approximation and qualitative properties of both the semigroups and the Markov processes are investigated as well. Most of the results of the paper depend on a representation of the semigroups we give in terms of powers of particular positive operators of discrete type we introduced and studied in a previous paper. 相似文献
49.
50.
In this paper we propose a continuous-time Markov chain to describe the spread of an infective and non-mortal disease into a community numerically limited and subjected to an external infection. We make a numerical simulation that shows tendencies for recurring epidemic outbreaks and for fade-out or extinction of the infection. 相似文献