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Patterns of genital tract Mustelid Gammaherpesvirus 1 (Musghv-1) reactivation are linked to stressors in European badgers (Meles meles)
No full textGammaherpesvirus reactivation can promote diseases or impair reproduction. Understanding reactivation patterns and associated risks of different stressors is therefore important. Nevertheless, outside the laboratory or captive environment, studies on the effects of stress on gammaherpesvirus reactivation in wild mammals are lacking. Here we used Mustelid gammaherpesvirus 1 (MusGHV-1) infection in European badgers (Meles meles) as a host–pathogen wildlife model to study the effects of a variety of demographic, physiological and environmental stressors on virus shedding in the genital tract. We collected 251 genital swabs from 150 free-ranging individuals across three seasons and screened them for the presence of MusGHV-1 DNA using PCR targeting the DNA polymerase gene. We explored possible links between MusGHV-1 DNA presence and seven variables reflecting stressors, using logistic regression analysis. The results reveal different sets of risk factors between juveniles and adults, likely reflecting primary infection and reactivation. In adults, virus shedding was more likely in badgers in poorer body condition and younger than 5 years or older than 7; while in juveniles, virus shedding is more likely in females and individuals in better body condition. However, living in social groups with more cubs was a risk factor for all badgers. We discuss possible explanations for these risk factors and their links to stress in badgers
Enhanced weathering to capture atmospheric carbon dioxide: Modeling of a trickle‐bed reactor
No full textEnhanced weathering (EW) of alkaline minerals can potentially capture CO2 from the atmosphere at gigaton scale, but the reactor design presents great challenges. We model EW with fresh water in a counter‐current trickle flow packed bed batch of 1–10 mm calcite particles. Weathering kinetics are integrated with the mass transfer of CO2 incorporating transfer enhancement by chemical reaction. To avoid flooding, flow rates must be reduced as the particles shrink due to EW. The capture rate is mainly limited by slow transfer of CO2 from gas to liquid although slow dissolution of calcite can also play a role in certain circumstances. A bed height of at least 7–8 m is required to provide sufficient residence time. The results highlight the need to improve capture rate and reduce energy and water consumption, possibly through enriching the feed with CO2 and further chemical acceleration of the mass transfer
Exciton dynamics in monolayer graphene grown on a Cu(111) surface
No full textWe have characterized the carrier dynamics of the excitonic emission emerging from a monolayer of graphene grown on a Cu(111) surface. Excitonic emission from the graphene, with strong and sharp peaks both with a full-width at half-maximum of 2.7 meV, was observed near ~3.16 and ~3.18 eV at 4.2 K. The carrier recombination parameters were studied by measuring both temperature-dependent and time-resolved photoluminescence. The intensity variation with temperature of these two peaks shows an opposing trend. The time-resolved emission was modelled using coupled differential equations and the decay time was found to be dominated by carrier trapping and Auger recombination as the temperature increased
China's online parrot trade: Generation length and body mass determine sales volume via price
No full textThe wildlife trade threatens global biodiversity and animal welfare, where parrots are among the taxa most frequently traded, supplying exotic pets and captive breeders worldwide. Using phylogenetic path analysis, we examine how biological factors interact with price to influence online protected parrot trade volumes in China, using transactions recorded for 46 species (n = 5862 individuals). Trade was greatest in smaller, faster breeding species that commanded a lower price. This price effect followed the economic law of demand, with Relatively Inelastic Demand (−0.758), outweighing indicators of ‘quality’ such as body coloration, and conservation status. We identify two areas of concern: those larger, slower-breeding, rarer species, even though sold at lower numbers, may be at conservation risk if harvested from the wild. In contrast, the sheer numbers (over 90% of the individuals were under median generation length, body mass and/or price) and ready availability of smaller and more common species comprises a substantial overall animal welfare issue, given that the capture, importation, or captive breeding of many parrot species in China is illegal and thus unregulated. Our investigation highlights the importance of properly understanding the internal relations among drivers of wildlife trade to inform appropriate management
Navigating the challenges of L2 reading: Self-efficacy, self-regulatory reading strategies and learner profiles
No full textReading in a foreign language has value for learners as a potentially rich source of input as well as enjoyment. It requires persistence, however. Within models of self‐regulated learning, persistence relates to learners’ self‐efficacy and use of strategies to aid task completion and regulation of engagement. Yet the relationship between self‐efficacy and self‐regulatory strategies is underexplored for second language (L2) reading, despite some intervention studies finding that instruction aimed at improving strategy use positively influences self‐efficacy. The current study investigated the relationship between what we call text engagement regulatory reading strategies (TERRS) and reading self‐efficacy among 529 beginner learners of French. It also explored whether different learner profiles exist with respect to that relationship, and how far learners of different profiles benefited in respect of reading self‐efficacy from 3 instructional approaches: phonics instruction plus the use of challenging texts; strategy‐based instruction using the same texts; and no explicit phonics or strategy instruction using the texts only. The use of TERRS was an important predictor of reading self‐efficacy and central to 3 distinct learner profile clusters. Increases in reading self‐efficacy were significantly greater for learners of certain profiles who received strategy‐based instruction, with implications for theories of self‐regulated language learning and classroom practice
A phylodynamic workflow to rapidly gain insights into the dispersal history and dynamics of SARS-CoV-2 lineages
No full textSince the start of the COVID-19 pandemic, an unprecedented number of genomic sequences of SARS-CoV-2 have been generated and shared with the scientific community. The unparalleled volume of available genetic data presents a unique opportunity to gain real-time insights into the virus transmission during the pandemic, but also a daunting computational hurdle if analyzed with gold-standard phylogeographic approaches. To tackle this practical limitation, we here describe and apply a rapid analytical pipeline to analyze the spatiotemporal dispersal history and dynamics of SARS-CoV-2 lineages. As a proof of concept, we focus on the Belgian epidemic, which has had one of the highest spatial densities of available SARS-CoV-2 genomes. Our pipeline has the potential to be quickly applied to other countries or regions, with key benefits in complementing epidemiological analyses in assessing the impact of intervention measures or their progressive easement
The Cuntz-Toeplitz algebras have nuclear dimension one
No full textWe prove that unital extensions of Kirchberg algebras by separable stable AF
algebras have nuclear dimension one. The title follows
The gut-microbiota as a target for the treatment of negative symptoms of schizophrenia: a systematic review and meta-analysis of controlled trials of add-on strategies: Conference abstract
No full textHomogenisation applied to thermal radiation in porous media
No full textHeat transport in granular and porous media occurs through conduction in the solid and radiation through the voids. By exploiting the separation of length scales between the small typical particles or voids and the large size of whole region, the method of multiple scales can be applied. For a purely diffusive system, this yields a problem on the macroscale with an effective conductivity, deduced by solving a ‘cell problem’ on the microscale. Here, we apply the method when radiation and conduction are both present; however, care must be taken to correctly handle the integral nature of the radiative boundary condition. Again, an effective conductivity is found by solving a ‘cell problem’ which, because of the non-linearity of radiative transfer, to be solved for each temperature value. We also incorporate modifications to the basic theory of multiple scales in order to deal with the non-local nature of the radiative boundary condition. We derive the multiple scales formulation of the problem and report on numerical comparisons between the homogenised problem and direct solution of the problem. We also compare the effective conductivity to that derived using Maxwell models and effective medium theory