0000000000575056
AUTHOR
A. Campos
Polymer-polymer interaction parameters in solvent/polymer/polymer ternary systems
Abstract Empirical equations defining the relationships between b23 and χ23 interaction parameters for the ternary systems toluene (1)/poly(dimethylsiloxane), PDMS, (2)/polystyrene, PS, (3) and benzene (1)/PDMS(2)/PS(3) have been determined. The dependences of both interaction parameters on the mean molecular weights of the macromolecular components have also been studied. A single dependence of b23 (or χ23) upon the mean molecular weight is found when both polymeric components have intermediate to high molecular weights. However, that single dependence is not found when the molecular size of polymer (2) is low.
SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study
Abstract Background Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18–49, 50–69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results NNVs were more favourable in su…
Determination of χ from liquid-liquid phase data in ternary polymer systems (solvent/polymer/polymer) with hydrogen bonding
Two different models accounting for the dependences of χ and g interaction parameters on both temperature and composition have been applied to different ternary polymer systems (TPS) solvent(1)/polymer(2)/polymer(3). The ana- lyzed TPS have consisted on ten different polymer mixtures in chloroform as common solvent that can specifically interact via hydrogen bond. Experimental ternary phase diagrams determined by liquid chromatography were taken from literature. The application of the two models to the experimental data have served to obtain χij and gij interaction parameters for all the binary ij (ij = 12, 13, 23) interactions established between the three components of the system, with si…
Parasite community diversity in two Mediterranean labrid fishes Symphodus tinea and Labrus merula
Examination of 111 peacock wrasse [Symphodus tinea (L.)] and 97 brown wrasse (Labrus merula L.) from the Valencian coast (Spain) yielded 24 metazoan parasite species (11 Digenea, three Cestoda, four Nematoda. one Acanlhocephala, five Crustacea). Eighteen species were from 5. tinea and 17 from L. merula; 11 of the 24 species were common to both hosts. Brillouin's diversity index, was applied to fully censused parasite infracommunities. This is the first time that all the metazoan parasites (internal and external) in any position in the host have been analysed for diversity. High values of prevalence, intensity, and diversity parameters indicate that these labrid fishes support diverse parasi…