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Abstract Graphene/polymer composites can be spun into fibers with remarkable mechanical, thermal and electrical properties, but few studies have considered requirements for the pilot-scale production of such fibers using commercially available graphene nanoplatelets (GnP). To address this limitation, we fabricated melt-spun polyamide 6 (PA6) multifilament yarns in which 3% or 5% (w/w) GnP was incorporated into the PA6 matrix by melt compounding during the initial process step. We tested a range of melt-spinning process parameters and analyzed the properties of the resulting fibers in detail. We were able to fabricate yarns containing 24 single filaments at a maximum winding speed of 1800 m/min while applying a draw ratio of 2.5. The electrical conductivity of the as-spun yarns was in the 10 μS/m range, which is suitable for the production of anti-static textiles. Furthermore, the degree of crystallization declined as the GnP content increased, reducing the tenacity of the yarn but improving its elastic modulus, allowing the production of composite textiles. In conclusion, we confirmed that large amounts of graphene can be incorporated into PA6 polymers by melt spinning and that the resulting composite fibers are suitable for multiple downstream applications in the textile industry. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

The malaria mosquito, Anopheles stephensi, and other mosquitoes modulate their biology to match the time-of-day. In the present work, we used a non-hypothesis driven approach (untargeted proteomics) to identify proteins in mosquito tissue, and then quantified the relative abundance of the identified proteins from An. stephensi bodies. Using these quantified protein levels, we then analyzed the data for proteins that were only detectable at certain times-of-the day, highlighting the need to consider time-of-day in experimental design. Further, we extended our time-of-day analysis to look for proteins which cycle in a rhythmic 24-hour (“circadian”) manner, identifying 31 rhythmic proteins. Finally, to maximize the utility of our data, we performed a proteogenomic analysis to improve the genome annotation of An. stephensi. We compare peptides that were detected using mass spectrometry but are ‘missing’ from the An. stephensi predicted proteome, to reference proteomes from 38 other primarily human disease vector species. We found 239 such peptide matches and reveal that genome annotation can be improved using proteogenomic analysis from taxonomically diverse reference proteomes. Examination of ‘missing’ peptides revealed reading frame errors, errors in gene-calling, overlapping gene models, and suspected gaps in the genome assembly. [ABSTRACT FROM AUTHOR]

The structural properties of novel melt-spun polymer optical fibers (POFs) are investigated by small-angle X-ray scattering. The amorphous PMMA POFs were subjected to a rapid cooling in a water quench right after extrusion in order to obtain a radial refractive index profile. Four fiber samples were investigated with small-angle X-ray scattering (SAXS). The resulting distance-distribution functions obtained from the respective equatorial and meridional SAXS data exhibit a real-space correlation peak indicative of periodic cross-sectional and axial variations in the scattering density contrast. Simple model calculations demonstrate how the structural information contained particularly in the equatorial distance distribution function can be interpreted. The respective results are qualitatively verified for one of the fiber samples by comparison of the model curve with the measured SAXS data. Eventually, the study confirms that the cross-sectional variation of the (scattering-) density is the main reason for the formation of radial refractive-index profiles in the POFs. [ABSTRACT FROM AUTHOR]