Simplest Prussian-blue deposition from ferric ferricyanide solution by a reducing Ag spot put onto an ITO substrate

This article was published in the Journal of Solid State Electrochemistry [© Springer-Verlag] and the definitive version is available at: http://dx.doi.org/10.1007/s10008-012-1811-7Prussian-blue (PB) film for electro-chromism can be electro-deposited on to an electrode (usually tin-doped indium oxide/glass) either directly from a PB colloid or from ferric ferricyanide in a two-electrode electro-chemical cell by applying a reductive potential. Alternatively, a “sacrificial” electron-producing silver flag electrode in the solution, when connected to the PB-receiving electrode, can effect the required reductive deposition. A silver spot, here innovatively applied as silver paint directly onto the deposition electrode, produces PB film on immersion in the iron(III)(III) solution, obviating the separate counter-electrode method

A computational analysis of the dynamic roles of talin, Dok1, and PIPKI for integrin activation

Integrin signaling regulates cell migration and plays a pivotal role in developmental processes and cancer metastasis. Integrin signaling has been studied extensively and much data is available on pathway components and interactions. Yet the data is fragmented and an integrated model is missing. We use a rule-based modeling approach to integrate available data and test biological hypotheses regarding the role of talin, Dok1 and PIPKI in integrin activation. The detailed biochemical characterization of integrin signaling provides us with measured values for most of the kinetics parameters. However, measurements are not fully accurate and the cellular concentrations of signaling proteins are largely unknown and expected to vary substantially across different cellular conditions. By sampling model behaviors over the physiologically realistic parameter range we find that the model exhibits only two different qualitative behaviours and these depend mainly on the relative protein concentrations, which offers a powerful point of control to the cell. Our study highlights the necessity to characterize model behavior not for a single parameter optimum, but to identify parameter sets that characterize different signaling modes

Nafion® as advanced immobilisation substrate for the voltammetric analysis of electroactive microparticles: the case of some artistic colouring agents

Voltammetry of microparticles is applied to characterise and to identify solid analytes of interest in the field of cultural heritage. Nafion® is used for the immobilisation of solid microparticles onto the surface of a glassy carbon electrode by exploiting the deposition onto the electrode surface of a micro-volume of a suspension of the microsample in polymeric solution. Cyclic voltammetry and square wave voltammetry are applied to characterise and to identify the microparticles immobilised in the Nafion® coating. The analyte studied in this work is Prussian Blue as a typical inorganic pigment, with a relatively simple electrochemical behaviour. The proposed method is applied to a sample of Venetian marmorino plaster. The performance of Nafion® for this analysis is compared with that of the polymer Paraloid B72

Online network organization of Barcelona en Comú, an emergent movement-party

Abstract The emerging grassroots party Barcelona en Comú won the 2015 Barcelona City Council election. This candidacy was devised by activists involved in the Spanish 15M movement to transform citizen outrage into political change. On the one hand, the 15M movement was based on a decentralized structure. On the other hand, political science literature postulates that parties develop oligarchical leadership structures. This tension motivates to examine whether Barcelona en Comú preserved a decentralized structure or adopted a conventional centralized organization. In this study we develop a computational methodology to characterize the online network organization of every party in the election campaign on Twitter. Results on the network of retweets reveal that, while traditional parties are organized in a single cluster, for Barcelona en Comú two well-defined groups co-exist: a centralized cluster led by the candidate and party accounts, and a decentralized cluster with the movement activists. Furthermore, results on the network of replies also shows a dual structure: a cluster around the candidate receiving the largest attention from other parties, and another with the movement activists exhibiting a higher predisposition to dialogue with other parties