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Solid wine wastes named wine lees (WL) have been tested as cost‐advantage filler within biopolymers such as poly(3‐hydroxybutyrate‐co‐hydroxyhexanoate) and poly(3‐hydroxybutyrate‐co‐hydroxyvalerate). WL have been first characterized and subsequently mixed within the polymers through a twin‐screw extruder in different concentrations (10, 20, and 40 phr). Moreover, the role of 3‐methacryloxypropyltrimethoxysilane tested as coupling agent has been investigated within the 20 phr formulation. The obtained materials have been characterized from a thermal, mechanical, rheological, and morphological point of view through: differential scanning calorimetry, melt flow rate, tensile and creep tests, dynamic mechanical analysis, and scanning electron microscopy. Results have shown how WL can improve the biopolymers overall properties without compromising their bio‐based origin. Several micromechanical models have been exploited to extend the mechanical behavior and correlations between biocomposites properties and WL contents have been carried out. Finally, the economic analysis has shown how these biocomposites could be suitable also for large‐scale applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48869. [ABSTRACT FROM AUTHOR]

Aim To assess the impact on fear of hypoglycaemia and treatment satisfaction with an artificial pancreas system used for 2 consecutive months, as well as participant acceptance of the artificial pancreas system. Methods In a randomized crossover trial patient-related outcomes associated with an evening-and-night artificial pancreas and sensor-augmented pump therapy were compared. Both intervention periods lasted 8 weeks. The artificial pancreas acceptance questionnaire (range 0-90, higher scores better), Hypoglycaemia Fear Survey II (range 0-72, higher scores worse) and Diabetes Treatment Satisfaction Questionnaire (range 0-36, higher scores better) were completed by 32 participants. Semi-structured interviews were conducted after study completion in a subset of six participants. Outcomes were compared using a repeated-measures anova model or paired t-test when appropriate. Results The total artificial pancreas acceptance questionnaire score at the end of the artificial pancreas period was 69.1 ( sd 14.7; 95% CI 63.5, 74.7), indicating a positive attitude towards the artificial pancreas. No significant differences were found among the scores at baseline, end of sensor-augmented pump therapy period or end of the artificial pancreas period with regard to fear of hypoglycaemia [28.2 ( sd 17.5), 23.5 ( sd 16.6) and 23.5 ( sd 16.7), respectively; P = 0.099] or diabetes treatment satisfaction [29.0 ( sd 3.9), 28.2 ( sd 5.2) and 28.0 ( sd 7.1), respectively; P = 0.43]. Themes frequently mentioned in the interviews were 'positive effects at work', 'improved blood glucose', 'fewer worries about blood glucose', but also 'frequent alarms', 'technological issues' and 'demand for an all-in-one device'. Conclusions The psychological outcomes of artificial pancreas and sensor-augmented pump therapy were similar. Current artificial pancreas technology is promising but user concerns should be taken into account to ensure utility of these systems. [ABSTRACT FROM AUTHOR]

Aims To test in an outpatient setting the safety and efficacy of continuous subcutaneous insulin infusion ( CSII) driven by a modular model predictive control ( MMPC) algorithm informed by continuous glucose monitoring ( CGM) measurement. Methods 13 patients affected by type 1 diabetes participated to a non-randomized outpatient 42-h experiment that included two evening meals and overnight periods (in short, dinner & night periods). CSII was patient-driven during dinner & night period 1 and MMPC-driven during dinner&night period 2. The study was conducted in hotels, where patients could move around freely. A CGM system ( G4 Platinum; Dexcom Inc., San Diego, CA, USA) and insulin pump ( AccuChek Combo; Roche Diagnostics, Mannheim, Germany) were connected wirelessly to a smartphone-based platform (DiAs, Diabetes Assistant; University of Virginia, Charlottesville, VA, USA) during both periods. Results A significantly lower percentage of time spent with glucose levels <3.9 mmol/l was achieved in period 2 compared with period 1: 1.96 ± 4.56% vs 12.76 ± 15.84% (mean ± standard deviation, p < 0.01), together with a greater percentage of time spent in the 3.9-10 mmol/l target range: 83.56 ± 14.02% vs 62.43 ± 29.03% (p = 0.04). In addition, restricting the analysis to the overnight phases, a lower percentage of time spent with glucose levels <3.9 mmol/l (1.92 ± 4.89% vs 12.7 ± 19.75%; p = 0.03) was combined with a greater percentage of time spent in 3.9-10 mmol/l target range in period 2 compared with period 1 (92.16 ± 8.03% vs 63.97 ± 2.73%; p = 0.01). Average glucose levels were similar during both periods. Conclusions The results suggest that MMPC managed by a wearable system is safe and effective during evening meal and overnight. Its sustained use during this period is currently being tested in an ongoing randomized 2-month study. [ABSTRACT FROM AUTHOR]

Silica nanoparticles were synthesized by means of a sol-gel method and generated in ethylene propylene diene monomer rubber (EPDM) by in situ synthesis. The properties were determined using scanning electron microscopy, attenuated total reflectance Fourier-transform infrared spectroscopy, thermogravimetric analysis, tensile testing, dynamic mechanical analysis, swelling tests, and gel content determination. The silica particles were homogenously dispersed in the EPDM matrix, with the presence of agglomerates, especially for high silica contents. The swelling experiments showed a decrease in the crosslinking density of the vulcanized rubber due to the presence of the silica nanoparticles. The mechanical properties, however, were significantly improved by the presence of the stiff silica nanoparticles. The effect of the amount of silica on the thermomechanical properties and thermal degradation of EPDM was also investigated. The presence of silica showed an increase in the storage and loss moduli at high temperatures, probably due to the increasing filler content. The thermal degradation analysis showed that the presence of silica particles incorporated in the EPDM matrix had no significant influence on the thermal stability of the composites. POLYM. COMPOS., 36:825-833, 2015. © 2014 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

The present work attempts to study the mechanical properties and toughness behavior of a typical acrylic melamine clearcoat modified by a polyester-amide hyperbranched polymer (HBP). Formulations were such that 0, 5, 10, 25 and 50% (molar percent) of total acrylic hydroxyl groups were stoichiometrically substituted by those of HBP. Bulk and surface of the clearcoats were studied by various mechanical techniques including hardness, tensile, dynamic mechanical thermal analysis (DMTA), nano-indentation and scratch tests. In addition a scanning electron microscope (SEM) was utilized to observe the morphology of the fractured films. The bulk mechanical properties showed that a low loading (5 molar %) of HBP was sufficient to considerably increase the bulk hardness, cross-linking density and toughness. DMTA and SEM results proved the occurrence of a single-phase blend and that the shear deformation was the main toughening mechanism of HBP modified clearcoats. In general, it was revealed that the HBP not only could act as an excellent compatible toughening agent, but also maintained the clarity of the clearcoat and increased its scratch resistance. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The sol-gel technique was used to reinforce isoprene rubber (IR) by generating silica in situ from tetraethoxysilane (TEOS). The aim of the research was to elucidate the effect of the preparation conditions on the structural and morphological characteristics of silica and the resulting mechanical reinforcement. The structure of the in situ generated silica was analyzed by 29Si high-resolution solid-state NMR spectroscopy, which evidenced a high condensation degree of TEOS that decreased with increasing the sol-gel reaction time. The silica dispersion became less homogeneous as the TEOS content and the reaction time were increased. The incorporation of a coupling agent (OTES, octyltriethoxysilane) in the reaction mixture promoted full conversion of TEOS. Lower particle size, better silica dispersion, and higher filler-matrix adhesion were noticed if the incorporation of OTES was delayed compared to TEOS. Uniaxial tensile tests evidenced that the tensile strength typically increased in the first 60 min of reaction and then leveled off. A similar behavior was observed for the high deformation stiffness, whereas at low deformations, the stiffness increased monotonically with the reaction time. In the vulcanizates with silica contents higher than 25 wt %, a drastic stiffness decrement was observed passing from low to high deformations. This reduction was ascribed to the disruption of the secondary filler network occurring in these materials when severely stretched. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

The article presents a study which used acicular titania nanoparticles to prepare nanocomposites filled at varying concentrations by melt mixing with a high density polyethylene (HDPE) matrix. The study found a decrease in the creep compliance for both the elastic and viscous components. The researchers recommended using untreated titania nanoparticles in reducing the creep compliance rather than the functionalized ones.

Hepatic synthesis of lipoproteins and apolipoproteins was investigated in male Wistar rats with severe nephrotic syndrome induced by puromycin aminonucleoside by incubating liver slices with a mixture ofC-amino acids. Labeled lipoproteins were separated by preparative ultracentrifugation from the incubation medium after the addition of carrier plasma. The incorporation ofC-amino acids into very low density lipoproteins (VLDL) (1.006 g/ml), low density lipoproteins (LDL) (1.006-1.063 g/ml) and high density lipoproteins (HDL) (1.063-1.210 g/ml) was increased in nephrotic liver 6.1-, 5.7- and 5.0-fold, respectively. The measurement of radioactivity associated to apolipoproteins isolated by SDS-PAGE documented an increased incorporation into apolipoprotein E (apoE) of nephrotic VLDL (33.1% vs 20% of the total radioactivity incorporated into VLDL apoproteins) and a markedly increased incorporation into apolipoprotein A-I (apoA-I) of nephrotic HDL (44.3% vs 16.3% of the total radioactivity incorporated into HDL apoproteins). In nephrotic liver, the total incorporation of amino acids into apolipoproteins (apoVLDL+apoLDL+apoHDL) was increased 12.6 times for apoA-I, 6.4 times for apoB, 5.0 times for apoE, 4.2 times for apoC+apoA-II and 2.5 times for apoA-IV. We suggest that, in nephrotic liver: (a) the synthesis of VLDL, LDL and HDL is increased, and (b) the total synthesis of apoA-I is selectively increased when compared to that of the other apolipoproteins. [ABSTRACT FROM AUTHOR]