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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.

In this work we propose a stochastic model for the design and planning of closed-loop supply chains.
Uncertainties in demand and return volumes are modelled together with uncertain transportation
costs. A two-stage stochastic programming is developed and a sensitivity analysis to the worst-case
probability is performed in order to test the solution robustness. Finally, in order to prove the
goodness of the stochastic approach, the value of the stochastic solution and the value of perfect
information are computed. An example based on a real case shows the model applicability.

This work aimed to study the effect of different pre-treatments applied to a potato peel residue, in a thermophilic Anaerobic Digestion (AD) process. All samples were subjected to a mechanical pre-treatment through milling to a particle size below 2 mm. The thermal pre-treatments applied consisted of autoclaving the residue at a gauge pressure of 1.2 bar, under a temperature of 122°C, and for 20, 35 and 55 minutes: assays E122.20, E122.35 and E122.55, respectively. The control assay was performed on a ground residue, which was not submitted to any thermal pre-treatment. All pre-treated residues were subjected to an AD process in a CSTR reactor at 49±1°C. The experimental data showed that the highest methane percentages were very similar (about 92% v/v) for all samples submitted to the thermal pre-treatments. For the control assay, the highest percentage of methane was 87.9% (v/v). The highest biogas yields were recorded in the trial E122.35 (646±50 cm3.g-1 CODremoved), against only 250±20 cm3.g-1 CODremoved for the control assay. The highest biogas yields for VSremoved were attained in the assays E122.55 and E122.35, with values of 646±48 cm3.g-1 VSremoved and 634±59 cm3.g-1 VSremoved, respectively. Globally, the yields registered for the assay E122.35 were similar to those determined in the assay E122.55. Due to the lower energy consumption during the pre-treatment performed in the assay E122.35, this was considered to be the most suitable pre-treatment for this type of residue.

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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Electrospun fibers of poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2) with exceptional electro-optical performance are obtained. The I/T characteristics measured in fibers with 7-15 μm diameter and 1 mm length show a semiconductor behavior; their thermal activation energy is 0.5 eV and the dark conductivity at RT is 5 × 10-9 (Ω cm)-1. Besides exhibiting a photosensitivity of about 60 under white light illumination with a light power intensity of 25 mW · cm-2, the fibers also attain RT photoluminescence in the cyan, yellow, and red wavelength range under ultraviolet, blue, and green light excitation, respectively. Optical microscope images of F8T2 reveal homogeneous electrospun fibers, which are in good agreement with the uniformly radial fluorescence observed. The production of electrospun fibers from poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-bithiophene] (F8T2) obtained without a carrier polymer is reported. The obtained fibers are shown to have properties suitable for organic fiber photovoltaic and sensors applications. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.