Non-catalytic cellulosomal carbohydrate-binding modules (CBMs) are responsible for increasing the catalytic efficiency of cellulosic enzymes by selectively putting the substrate (a wide range of poly- and oligosaccharides) and enzyme into close contact. In the present work we carried out an atomistic rationalization of the molecular determinants of ligand specificity of a family 11 CBM from thermophilic C. thermocellum (CtCBM11), based on a NMR and molecular modeling approach. We have determined the NMR solution structure of CtCBM11 at 25 and 50 ºC and derived information on the residues of the protein involved in ligand recognition and on the influence of the length of the saccharide chain on binding. We obtained models of the CtCBM11/cellohexaose and CtCBM11/cellotetraose complexes by docking in accordance with the NMR experimental data. Specific ligand/protein CH-π and Van der Waals interactions were found to be determinant for the stability of the complexes and for defining specificity. Using the order parameters derived from backbone dynamics analysis in the presence and absence of ligand and at 25 and 50 ºC, we determined that the protein’s backbone conformational entropy is slightly positive. This data in combination with the negative binding entropy calculated from ITC studies supports a selection mechanism where a rigid protein selects a defined oligosaccharide conformation.

A novel porous polymer-ionic liquid composite with poly(2-hydroxyethyl methacrylate) (PHEMA) and 1-butyl-3-methylimidazolium hexafluorophosphate (BMIPF6) has been synthesized by γ-irradiation without heat or chemical initiators. The products can be reversibly converted into organogels. The composites are potential candidates for electrochemical applications. The use of γ-radiation can be a simple and versatile alternative way to obtain these materials.

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The advancement of CMOS technology led to the integration of more complex functions. In the particular of wireless transceivers, integrated LC tanks are becoming popular both for VCOs and integrated filters [1]. For RF applications the main challenge is still the design of integrated inductors with the maximum quality factor. For that purpose, tapered, i.e., variable width inductors have been proposed in the literature. In this paper, analytical expressions for the determination the pi-model parameters, for the characterization of variable width integrated inductors are proposed. The expressions rely exclusively on geometrical and technological parameters, thus granting the rapid adaptation of the model to different technologies. The results obtained with the model are compared against simulation with ASITIC, showing errors below 10%. The model is then integrated into an optimization procedure where inductors with a quality factor improvement in the order of 20-30% are obtained, when compared with fixed width inductors.

Progressive scaling of CMOS technology towards nanoscale regime enables the design of highly integrated systems for the wireless communications market. As technology continues to scale, the variability in process parameters may cause significant deviations in device behaviour. The complexity of designing spiral inductors has lead to the development of multi-objective optimization based design methodologies yielding the generation of Pareto-optimal surfaces. However, the variability of the process parameters is usually ignored, yielding the selection of ideally optimal solutions in detriment of quasi-optimal solutions that may prove to be better, should the robustness against process parameter variation be accounted for. We propose the generation of an extended Pareto front containing both optima and quasi-optima solutions. Finally information on the robustness to process parameter variations, is used for electing the best design solutions.The evaluation of the extended set of sub-optima solutions requires methods capable to find the set of local optima, since solutions that are close to each other in the performance index space may be very distant in the design parameter space.

Natural polymers have been studied during the last years for the transport and separation of liquid and gas mixtures, in terms of solubility and permeability data, and their structure and mechanical properties have been characterised. However, no transport models have been reported, relating transport with the material morphology. Cork is a natural cellular material containing three structural polymers (suberin, lignin and polysaccharides). Cork is considered a natural polymer, with economic relevance due to its sealing, non-toxic, stable and low-density properties. Corkwas characterised in this work in terms of its solubility and permeability data in relation to various gases with different molecular mass: He, O2,N2,CO2 and 1,1,1,2-tetrafluoroethane (R134a). A morphological analysis of the structure of the cork sample chosen in this work was also performed using SEM (scanning electron microscopy) and TEM (transmission electron microscope) image analysis, which took into account the variation of each relevant structural parameter. A transport model was developed supported on the morphology of cork characterised in this work. The transport model developed considers that gas permeation occurs through the plasmodesmata, which are channels with approximately 100 nm of diameter that cross the cell walls of the cork cells. It was found that gas transport follows a Knudsen mechanism, as proved by the gas permeability behaviour with increasing gasmolecularmass, with a negligible contribution of viscous transport to the total flux. &

{New cationic Ag(I) complexes were prepared by reaction of AgBF4 with two thioether-functionalized bis-(diphenylphosphino) amine ligands, Ph2PN(p-ArSMe)PPh2 (L1) and Ph2PN(n-PrSMe)PPh2 (L2), and compared with those obtained from the unfunctionalized ligands Ph2PN(Ph)PPh2 (L3) and Ph2PN(n-Bu)PPh2 (L4), respectively. The complex {[}Ag-3(mu(3)-Cl)(2)(mu(2)-L1-P, P)(3)](BF4) (1 center dot BF4) contains a triangular array of Ag centres supported by three bridging L1 ligands and two triply-bridging chlorides. In contrast, ligand L2 led to the coordination polymer {[}\{Ag-2(mu(3)-L2,-P,P,S)(2)(MeCN)(2)\}\{Ag-2(mu(2)-L2-P,P)(2)(MeCN)(2) \}(BF4)(4)](n) (2) in which the tethered thioether group connects intermolecularly a Ag2 unit to the diphosphine bridging the other Ag2 unit. With L3 and L4, two similar complexes were obtained, {[}Ag-2(mu(2)-L3)(BF4)(2)] (3) and {[}Ag-2(mu(2)-L4)(BF4)(2)] (4), respectively, with bridging diphosphine ligands and a BF4 anion completing the coordination sphere of the metal. Complexes 1 center dot BF4 center dot CH2Cl2, 2 center dot THF, 3 center dot 3CH(2)Cl(2) and 4 have been fully characterized, including by single crystal X-ray diffraction.}

Transport properties of natural (noncompressed) cork were evaluated for water and ethanol in both vapor and liquid phases. The permeability for these permeants has been measured, as well as the sorption and diffusion coefficients. This paper focuses on the differences between the transport of gases' relevant vapors and their liquids (water and ethanol) through cork. A transport mechanism of vapors and liquids is proposed. Experimental evidence shows that both vapors and liquids permeate not only through the small channels across the cells (plasmodesmata), as in the permeation of gases, but also through the walls of cork cells by sorption and diffusion as in dense membranes. The present study also shows that cork permeability for gases was irreversibly and drastically decreased after cork samples were exposed to ethanol or water in liquid phase.