Branching at the alkyl side chain of the imidazolium cation in ionic liquids (ILs) was evaluated towards its effect on carbon dioxide (CO2 ) solubilization at 10 and 80 bar (1 bar=1x10(5) Pa). By combining high-pressure NMR spectroscopy measurements with molecular dynamics simulations, a full description of the molecular interactions that take place in the IL-CO2 mixtures can be obtained. The introduction of a methyl group has a significant effect on CO2 solubility in comparison with linear or fluorinated analogues. The differences in CO2 solubility arise from differences in liquid organization caused by structural changes in the cation. ILs with branched cations have similar short-range cation-anion orientations as those in ILs with linear side chains, but present differences in the long-range order. The introduction of CO2 does not cause perturbations in the former and benefits from the differences in the latter. Branching at the cation results in sponge-like ILs with enhanced capabilities for CO2 capture.

Multiheme cytochromes have been implicated in Geobacter sulfurreducens (Gs) extracellular electron transfer (EET). These proteins are potential targets to improve EET and enhance bioremediation and electrical current production by Gs. However, the functional characterization of multiheme cytochromes is particularly complex due to the co-existence of several microstates in solution, connecting the fully reduced and fully oxidized states. Over the last decade, new strategies have been developed to characterize multiheme redox proteins functionally and structurally. These strategies were used to reveal the functional mechanism of Gs multiheme cytochromes and also to identify key residues in these proteins for EET. In previous studies, we set the foundations for enhancement of the EET abilities of Gs by characterizing a family of five triheme cytochromes (PpcA-E). These periplasmic cytochromes are implicated in electron transfer between the oxidative reactions of metabolism in the cytoplasm and the reduction of extracellular terminal electron acceptors at the cell’s outer surface. The results obtained suggested that PpcA can couple e-/H+ transfer, a property that might contribute to the proton electrochemical gradient across the cytoplasmic membrane for metabolic energy production. The structural and functional properties of PpcA were characterized in detail and used for rational design of a family of 23 single site PpcA mutants. In this review, we summarize the functional characterization of the native and mutant proteins. Mutants that retain the mechanistic features of PpcA and adopt preferential e-/H+ transfer pathways at lower reduction potential values compared to the wild-type protein were selected for in vivo studies as the best candidates to increase the electron transfer rate of Gs. For the first time Gs strains have been manipulated by the introduction of mutant forms of essential proteins with the aim to develop and improve bioelectrochemical technologies.

Foods are partially crystalline partially amorphous systems. Edible films are considered good models for food systems due to their interesting physical properties, quite straightforward matrices, and easy reproduction. Chitosan is a semicrystalline biopolymer, biocompatible, biodegradable, with antimicrobial activity and filmogenic properties, thoroughly used in edible films' studies. This work aims to investigate the relationship between chitosan films' molecular relaxation time, their microstructure (crystallinity) and functional properties. Analyses were carried out using data on chitosan/glycerol films prepared with different polymer/plasticisant concentrations. Results demonstrate that there is a relationship between macroscopic properties and water and glycerol relaxation times. Moreover, results show that while water is free in the matrix, glycerol is linked to the chitosan polymeric chains, decreasing intermolecular attractions and increasing free volume, thus facilitating molecular migration. Also the data analysis reveals the usefulness of NMR and molecular mobility studies in the matrix for characterisation and development of polymeric structures. Industrial relevance: NMR spectroscopy is currently one of the key methods for food characterisation. Foodstuff is a complex matrix including many different compounds with different chemical structures, concentrations, solubility, properties and nutritional values. From a fundamental perspective, foods are mainly edible and digestible biopolymers that are partially crystalline/partially amorphous and thus edible films, specifically chitosan/glycerol films can be very interesting food model systems for mobility and microstructure studies. Studies on water and solids' mobility and thermo-mechanical properties in food systems (real or model systems),are fundamental to fully attain food physical properties and stability. These studies may be extremely useful for food product and process design, safety and sensorial attributes and also for better understanding and predicting, for example, food storage stability conditions. (C) 2015 Elsevier Ltd. All rights reserved.

Since long ago cellulosic lyotropic liquid crystals were thought as potential materials to produce fibers competitive with spidersilk or Kevlar, yet the processing of high modulus materials from cellulose-based precursors was hampered by their complex rheological behavior. In this work, by using the Rheo-NMR technique, which combines deuterium NMR with rheology, we investigate the high shear rate regimes that may be of interest to the industrial processing of these materials. Whereas the low shear rate regimes were already investigated by this technique in different works [1-4], the high shear rates range is still lacking a detailed study. This work focuses on the orientational order in the system both under shear and subsequent relaxation process arising after shear cessation through the analysis of deuterium spectra from the deuterated solvent water. At the analyzed shear rates the cholesteric order is suppressed and a flow-aligned nematic is observed which for the higher shear rates develops after certain time periodic perturbations that transiently annihilate the order in the system. During relaxation the flow aligned nematic starts losing order due to the onset of the cholesteric helices leading to a period of very low order where cholesteric helices with different orientations are forming from the aligned nematic, followed in the final stage by an increase in order at long relaxation times corresponding to the development of aligned cholesteric domains. This study sheds light on the complex rheological behavior of chiral nematic cellulose-based systems and opens ways to improve its processing. (C) 2015 Elsevier Ltd. All rights reserved.

Gold glyconanoparticles (GlycoNPs) are full of promise in areas like biomedicine, biotechnology and materials science due to their amazing physical, chemical and biological properties. Here, siRNA GlycoNPs (AuNP@PEG@Glucose@siRNA) in comparison with PEGylated GlycoNPs (AuNP@PEG@Glucose) were applied in vitro to a luciferase-CMT/167 adenocarcinoma cancer cell line and in vivo via intratracheal instillation directly into the lungs of B6 albino mice grafted with luciferase-CMT/167 adenocarcinoma cells. siRNA GlycoNPs but not PEGylated GlycoNPs induced the expression of pro-apoptotic proteins such as Fas/CD95 and caspases 3 and 9 in CMT/167 adenocarcinoma cells in a dose dependent manner, independent of the inflammatory response, evaluated by bronchoalveolar lavage cell counting. Moreover, in vivo pulmonary delivered siRNA GlycoNPs were capable of targeting c-Myc gene expression (a crucial regulator of cell proliferation and apoptosis) via in vivo RNAi in tumour tissue, leading to an similar to 80% reduction in tumour size without associated inflammation.

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In this work we calculate photoionization and X-ray production cross-sections (XPCS) of M-shell vacancies in Hg at incident photon energy of 5.96 keV (low.

Responsible Research and Innovation (RRI) is a normative concept that has captured considerable attention on the Science and Technology (S&T) policy level, but also in academic discourses. It represents a new approach to how science, innovation and research can be shaped in accordance with societal values that builds directly on the concepts and methodologies of Technology Assessment (TA). The definition and operationalization aspects of RRI remain still unclear although key ingredients such as ethical acceptability are well established in S&T debates and embrace a spectrum of standard methodological approaches. In this paper we review the conceptual debate on RRI with a focus on its constituent parts. We then present a functional comparison between RRI and TA that proves the considerable conceptual overlap in the two approaches. We argue that TA methodologies and precepts should be employed as key operationalisational features in RRI. Finally we argue for a global perspective on RRI by describing a case study on global ethics in S&T that introduces an analytical framework for ethics debates.

Abstract Recovery of fully aggregated water-soluble CdTe quantum dots was achieved by simple treatment with a strong base. A deprotonation-triggered disaggregation is postulated to be the main mechanism involved in the quantum dots “reborn” process.

In the last 30 years we have assisted to a massive advance of nanomaterials in material science. Nanomaterials and structures, in addition to their small size, have properties that differ from those of larger bulk materials, making them ideal for a host of novel applications. The spread of nanotechnology in the last years has been due to the improvement of synthesis and characterization methods on the nanoscale, a field rich in new physical phenomena and synthetic opportunities. In fact, the development of functional nanoparticles has progressed exponentially over the past two decades. This work aims to extensively review 30 years of different strategies of surface modification and functionalization of noble metal (gold) nanoparticles, magnetic nanocrystals and semiconductor nanoparticles, such as quantum dots. The aim of this review is not only to provide in-depth insights into the different biofunctionalization and characterization methods, but also to give an overview of possibilities and limitations of the available nanoparticles.

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