Keratin–polyhydroxyalkanoate melt‐compounded composites with improved barrier properties of interest in food packaging applications

Sustainable biocomposite materials based on the combination of polyhydroxyalkanoates with a keratin additive derived from poultry feathers were successfully developed via melt compounding. Suitable dispersions for low loadings of the additive in the biopolymeric matrix were achieved by the melt‐mixing technique. A good physical interaction between the polymeric matrix and the additive was observed by scanning electron microscopy (SEM). Reductions in water, limonene, and oxygen permeability of the pure polymer to less than a half of its initial value for the composite containing 1 wt % of keratin additive were achieved. This composition was also found to exhibit optimum mechanical performance. As a result, these materials offer significant potential in fully renewable packaging applications based on polyhydroxyalkanoates with enhanced barrier performance. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39947.     

Toughening effects of titanium dioxide nanoparticles on TiO2/epoxy resin nanocomposites

The purpose of this study was to investigate the influence of adding different volume concentrations of titanium dioxide (TiO₂) nanoparticles to an Araldite LY 564 epoxy resin. In order to characterize the nanoparticles toughening effects, compact tension specimens were used to determine the plane strain fracture toughness (K_IC). Additionally, elastic modulus, tensile strength, and maximum sustained strain were measured in mechanical tensile tests. Composites were analyzed by means of electronic microscopy, both TEM and SEM, to check the dispersion quality of the nanoparticles in thepolymer matrix and to study the observed toughening mechanisms of the fillers. Addition of TiO₂ nanoparticles could simultaneously improve the stiffness and the toughness of the epoxy resin. POLYM. COMPOS., 31:1241–1246, 2010. © 2009 Society of Plastics Engineers     

Cell Proliferation in the Piriform Cortex of Rats with Motor Cortex Ablation Treated with Growth Hormone and Rehabilitation

Traumatic brain injury represents one of the main health problems in developed countries. Growth hormone (GH) and rehabilitation have been claimed to significantly contribute to the recovery of lost motor function after acquired brain injury, but the mechanisms by which this occurs are not well understood. In this work, we have investigated cell proliferation in the piriform cortex (PC) of adult rats with ablation of the frontal motor cortex treated with GH and rehabilitation, in order to evaluate if this region of the brain, related to the sense of smell, could be involved in benefits of GH treatment. Male rats were either ablated the frontal motor cortex in the dominant hemisphere or sham-operated and treated with GH or vehicle at 35 days post-injury (dpi) for five days. At 36 dpi, all rats received daily injections of bromodeoxyuridine (BrdU) for four days. We assessed motor function through the paw-reaching-for-food task. GH treatment and rehabilitation at 35 dpi significantly improved the motor deficit caused by the injury and promoted an increase of cell proliferation in the PC ipsilateral to the injury, which could be involved in the improvement observed. Cortical ablation promoted a greater number of BrdU+ cells in the piriform cortex that was maintained long-term, which could be involved in the compensatory mechanisms of the brain after injury.     

Effects of Lifestyle Intervention in Tissue-Specific Lipidomic Profile of Formerly Obese Mice

Lipids are highly diverse in their composition, properties and distribution in different biological entities. We aim to establish the lipidomes of several insulin-sensitive tissues and to test their plasticity when divergent feeding regimens and lifestyles are imposed. Here, we report a proton nuclear magnetic resonance (¹H-NMR) study of lipid abundance across 4 tissues of C57Bl6J male mice that includes the changes in the lipid profile after every lifestyle intervention. Every tissue analysed presented a specific lipid profile irrespective of interventions. Glycerolipids and fatty acids were most abundant in epididymal white adipose tissue (eWAT) followed by liver, whereas sterol lipids and phosphoglycerolipids were highly enriched in hypothalamus, and gastrocnemius had the lowest content in all lipid species compared to the other tissues. Both when subjected to a high-fat diet (HFD) and after a subsequent lifestyle intervention (INT), the lipidome of hypothalamus showed no changes. Gastrocnemius and liver revealed a pattern of increase in content in many lipid species after HFD followed by a regression to basal levels after INT, while eWAT lipidome was affected mainly by the fat composition of the administered diets and not their caloric density. Thus, the present study demonstrates a unique lipidome for each tissue modulated by caloric intake and dietary composition.     

Synthesis, characterization and evaluation of NiMo/SiO2–Al2O3 catalysts prepared by the pH-swing method

NiMo/(X)SiO₂–Al₂O₃ catalysts were synthesized with various SiO₂ contents (X = 0, 10, 25 and 50 wt%) using the pH-swing method. In order to find the optimum SiO₂ content, the catalysts were evaluated in the hydrodesulfurization of 4,6-DMDBT, hydrogenation of naphthalene and hydrodenitrogenation of carbazole. Kinetic parameters of Langmuir–Hinshelwood type equations for all the reaction systems were estimated. FTIR analysis of CO adsorption for the sulfided catalysts shows that the amount of coordinatively unsaturated Mo sites promoted by nickel (CUS-NiMoS) follows the order NiMo/10ASA > NiMo/25ASA > NiMo/0ASA. This tendency agrees with the results obtained in catalytic activity.     

Experiment Dashboard for Monitoring Computing Activities of the LHC Virtual Organizations

The Large Hadron Collider (LHC) is preparing for data taking at the end of 2009. The Worldwide LHC Computing Grid (WLCG) provides data storage and computational resources for the high energy physics community. Operating the heterogeneous WLCG infrastructure, which integrates 140 computing centers in 33 countries all over the world, is a complicated task. Reliable monitoring is one of the crucial components of the WLCG for providing the functionality and performance that is required by the LHC experiments. The Experiment Dashboard system provides monitoring of the WLCG infrastructure from the perspective of the LHC experiments and covers the complete range of their computing activities. This work describes the architecture of the Experiment Dashboard system and its main monitoring applications and summarizes current experiences by the LHC experiments, in particular during service challenges performed on the WLCG over the last years.