Factors affecting the local distribution of <i>Polystigma rubrum</i> stromata on <i>Prunus spinosa</i>

Background and aims – Polystigma rubrum forms orange-red stromata on the surface of living leaves of Prunus spinosa and P. domestica. Records suggests that this fungus now has a much more limited distribution in Britain than recorded in the 19th and early 20th century. Methods – We studied the local distribution of the fungus in the Burren Hills of western Ireland where it remains very common. Key results – Assessment of the local distribution of the fungus over two years found stromata to occur more frequently on P. spinosa leaves in hedgerows than woodlands. On individual trees in areas of open limestone pavement, the frequency of stromata was ten times higher in 2016 than 2015, possibly related to interannual rainfall differences. On hedgerow trees subjected to winter flooding, stromata were much less abundant, whereas stromata were more abundant on leaves also infected by the gall mite Eriophyes prunispinosae. The identity of Po. rubrum was confirmed by ITS sequencing.Conclusion – At a field location where Po. rubrum stromata are present in unusually high abundance, the distribution of stromata on trees in different habitats showed high levels of variation linked to both habitat and the presence of gall mites. Further work is required to determine whether variation in leaf surface and soil moisture are the key determinants of the observed distribution. Such investigations may reveal why Po. rubrum, once common in northern Europe is now restricted mainly to westerly, coastal locations

Really Trying or Merely Trying

We enjoy first-person authority with respect to a certain class of actions: for these actions, we know what we are doing just because we are doing it. This paper first formulates an epistemological principle that captures this authority in terms of trying to act in a way that one has the capacity to act. It then considers a case of effortful action – running a middle distance race – that threatens this principle. And proposes the solution of changing the metaphysics of action: one can keep hold of the idea that we have first-person authority over what we are doing by adopting a disjunctive account of action

Constraints on the neutron star equation of state from AT2017gfo using radiative transfer simulations

The detection of the binary neutron star merger GW170817 together with the observation of electromagnetic counterparts across the entire spectrum inaugurated a new era of multimessenger astronomy. In this study, we incorporate wavelength-dependent opacities and emissivities calculated from atomic-structure data enabling us to model both the measured light curves and spectra of the electromagnetic transient AT2017gfo. Best fits of the observational data are obtained by Gaussian Process Regression, which allows us to present posterior samples for the kilonova and source properties connected to GW170817. Incorporating constraints obtained from the gravitational wave signal measured by the LIGO-Virgo Scientific Collaboration, we present a 90 per cent upper bound on the mass ratio q ≲ 1.38 and a lower bound on the tidal deformability of Λ ≳ 197, which rules out sufficiently soft equations of state. Our analysis is a path-finder for more realistic kilonova models and shows how the combination of gravitational wave and electromagnetic measurements allow for stringent constraints on the source parameters and the supranuclear equation of state

An ancient dental gene network regulates development and continuous regeneration of teeth in sharks

The appearance of toothed vertebrates has proven a major determinant of the overall success of this lineage. This is most apparent in sharks and rays (elasmobranchs), which further retain the capacity for life-long tooth regeneration. Given their comparatively basal phylogenetic position, elasmobranchs therefore offer the opportunity for crucial insights into putative ancestral characters of tooth development, yet despite their evolutionary significance this remains poorly understood. Using the established chondrichthyan model, the catshark (Scyliorhinus sp.), we identified the expression of genes representative of conserved signaling pathways during stages of early dental competence, tooth initiation and regeneration. The expression patterns of β-catenin, shh, bmp4, pax9, pitx1/2, and the stem cell marker Sox2, characterise an ancestrally conserved gene set deployed during initiation of the elasmobranch dentition, suggesting that all vertebrate dentitions are defined by the expression of this core set of genes. These findings provide novel evidence to support the conservation in deep evolutionary time of a core set of dental patterning genes, therefore further defining the evolutionary trajectory of tooth development. We show how these genes facilitate the emergence of the shark dentition and offer insights into their deployment during development of the dental lamina, a sheet of dental epithelial cells that are responsible for continuous tooth regeneration. This study further promotes a specific experimental agenda to further characterise the roles of these core developmental genes during vertebrate tooth development, and importantly dental regeneration

Self-reported medication use among pregnant and breastfeeding women during the COVID-19 pandemic ::a cross-sectional study in five european countries

Insight into the epidemiology of perinatal medication use during the COVID-19 pandemic is scarce. Therefore, a cross-sectional study using an anonymous web survey was performed in Ireland, Norway, Switzerland, The Netherlands, and United Kingdom (UK) to investigate the prevalence and type of medications used by pregnant and breast-feeding women during the first pandemic wave. Factors associated with medication use were estimated by logistic regression. In total, 8378 women participated (i.e., 3666 pregnant and 4712 breastfeeding women). Most responses were collected in Norway (34%) and The Netherlands (28%), followed by Switzerland (19%), Ireland (17%) and UK (2%). Participants were more often professionally active and more often had a higher educational level compared to the general birthing population in each country. Overall, approximately 60% of women reported having used at least 1 medication in the preceding 3 months. Daily and occasional use was reported by 34% and 42% of pregnant and 29% and 44% of breastfeeding women. The most prevalent ATC (Anatomical Therapeutic Chemical) categories were the nervous system, the respiratory system, the alimentary tract/metabolism, and the musculo-skeletal system. Paracetamol, ibuprofen, antacids, and cetirizine were the most frequently used medications. The rate of antibacterial use was lower than previously reported. Having a chronic illness, country, maternal age, SARS-CoV-2 testing, professional status and time since delivery were associated with medication use. In conclusion, perinatal medication use was highly prevalent during the first pandemic wave, underlining the importance of maintaining counseling efforts on medication use, even in times of disrupted healthcare services and/or limited resources