A new latent accelerator and study of its effect on physical,mechanical and shelf-life of carbon fiber epoxy prepreg

The effects of a new latent accelerator and those of two common accelerators of 1-methyl imidazole and 2,4,6-tris(dimethylaminomethyl)phenol (DMP) have been studied in relation to the properties of dicyandiamide (dicy) cured epoxy resin and its prepregs with unidirectional carbon fiber. The new prepared accelerator is an adduct based on DMP (A_DMP). The results showed that the curing behavior of epoxy/dicy did not change when the appropriate amount of new accelerator was used. The amount of 5 phr of new latent accelerator is equal to the amount of 0.6 phr of DMP accelerator and by increasing the amount of new accelerator, the curing reaction of epoxy/dicy increased significantly. Viscosity build-up results and gel time measurements showed the high pot-life of resin system (epoxy/Dicy/A_DMP) and the high shelf-life of their prepreg. The results showed that the lap shear strength of sample containing 5 phr of the new accelerator (A_DMP5) was increased by 127% in comparison to the sample containing 0.6 phr of DMP. Transverse tensile strength and strain-at-break were increased by 27% and 31.7%, respectively. Transverse flexural strength, flexural strain-at-break and flexural modulus increased by 52%, 11% and 60%, respectively. On the other hand, fracture toughness and fracture energy increased significantly by 214% and 700%, respectively. This increase in mechanical properties was due to the bulkiness of the new latent accelerator acting as a toughening agent and also the good adhesion of fiber to the matrix as revealed by scanning electron microscopy.

     

Influence of functional information on consumer liking and consumer perception related to health claims for blueberry functional beverages

The objective of this study was to investigate the impact of functional labelling on the consumers acceptability and purchase intentions of blueberry functional beverages (BFB). A 2‐day consumer acceptance test was conducted independently with functional information (n = 60) and without any information (n = 80). The presence of functional labelling did not influence the liking attributes of BFBs (P > 0.05). However, functional information positively affected consumer perception of health‐related perceptions associated with BFBs, such as ‘aiding eye health improvement’ and ‘eye fatigue relief’. Subjects perceived more health‐related perceptions when informed test was conducted. The first‐order effect was observed, in which the degree of the first‐order effect was greater for BFBs that had a thicker mouthfeel. Findings from the results can practically guide product developers and marketers in the functional drink industry by providing the strategy for how to evaluate reformulated functional beverages for the consumer acceptance test by warning a counter‐balanced sample presentation.     

Biosynthesis,characterization and cytotoxic activity of CeO2 nanoparticles

Cerium oxide nanoparticles (CeO₂-NPs) have been biosynthesized using the aqueous extract of aerial parts of Prosopis farcta. This plant contains phenolic compounds that function as reducing and capping agents. Biosynthesized particles have been characterized through the use of UV–vis, PXRD, TEM, FESEM, EDX, Raman and FTIR analysis. The UV–vis spectrum clearly showed absorption peak at 317?nm, which indicated the formation of spherical CeO₂-NPs. It displayed in the FESEM and TEM images that the biosynthesized particles are uniformly and spherically shaped with a size of about 30?nm, while the EDX has clearly shown that only the elements Ce and O are present in the biosynthesized sample. Moreover, the Raman spectrum of synthesized nanoparticles has displayed a Ce-O stretching band at a measurement of 459?cm^?1. The cytotoxic activity of biosynthesized nanoparticles against the HT-29 cancer cell line was studied using the MTT assay. All the concentrations of CeO₂-NPs (0–800?µg/ml) showed non-toxic effects and thus, it can be suggested that these nanoparticles have the potential of being utilized in various fields of medicine, such as drug delivery.     

Cachexia,a Systemic Disease beyond Muscle Atrophy

Cachexia is a complication of dismal prognosis, which often represents the last step of several chronic diseases. For this reason, the comprehension of the molecular drivers of such a condition is crucial for the development of management approaches. Importantly, cachexia is a syndrome affecting various organs, which often results in systemic complications. To date, the majority of the research on cachexia has been focused on skeletal muscle, muscle atrophy being a pivotal cause of weight loss and the major feature associated with the steep reduction in quality of life. Nevertheless, defining the impact of cachexia on other organs is essential to properly comprehend the complexity of such a condition and potentially develop novel therapeutic approaches.     

An accurate analysis of the nonlinear power amplifier effects on SC-FDMA signals

Wireless Networks - Single carrier-frequency division multiple access (SC-FDMA) is a multiple access technique in broadband wireless networks which has been adapted by 3GPP for uplink transmission...     

A privacy-preserving distributed transfer learning in activity recognition

Telecommunication Systems - Along with the widespread use of smartphones, activity recognition using embedded inertial sensors has intrigued researchers. The learning and employing activity...     

Mechanistic Insights into the Allosteric Regulation of the Clr4 Protein Lysine Methyltransferase by Autoinhibition and Automethylation

Clr4 is a histone H3 lysine 9 methyltransferase in Schizosaccharomyces pombe that is essential for heterochromatin formation. Previous biochemical and structural studies have shown that Clr4 is in an autoinhibited state in which an autoregulatory loop (ARL) blocks the active site. Automethylation of lysine residues in the ARL relieves autoinhibition. To investigate the mechanism of Clr4 regulation by autoinhibition and automethylation, we exchanged residues in the ARL by site-directed mutagenesis leading to stimulation or inhibition of automethylation and corresponding changes in Clr4 catalytic activity. Furthermore, we demonstrate that Clr4 prefers monomethylated (H3K9me1) over unmodified (H3K9me0) histone peptide substrates, similar to related human enzymes and, accordingly, H3K9me1 is more efficient in overcoming autoinhibition. Due to enzyme activation by automethylation, we observed a sigmoidal dependence of Clr4 activity on the AdoMet concentration, with stimulation at high AdoMet levels. In contrast, an automethylation-deficient mutant showed a hyperbolic Michaelis–Menten type relationship. These data suggest that automethylation of the ARL could act as a sensor for AdoMet levels in cells and regulate the generation and maintenance of heterochromatin accordingly. This process could connect epigenome modifications with the metabolic state of cells. As other human protein lysine methyltransferases (for example, PRC2) also use automethylation/autoinhibition mechanisms, our results may provide a model to describe their regulation as well.