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3′H-spiro[dibenzo[c,h]xanthene-7,1′-isobenzofuran]-3′-one
Get PDFTarget compound 3′H-spiro[dibenzo[c,h]xanthene-7,1′-isobenzofuran]-3′-one ( 1 ) has long been known to be a by-product obtained from the preparation of naphtholphthalein. The structure of compound 1 was elucidated in the early 20th century; however, this compound has not previously been fully characterized using modern techniques. In this report, 1H NMR and 13C NMR spectra are provided. X-ray crystallography is also used to characterize the title compound for the first time.Peer reviewe
Contrafreeloading in kea (Nestor notabilis) in comparison to Grey parrots (Psittacus erithacus)
Get PDFContrafreeloading-working to access food that could be freely obtained-is rarely exhibited and poorly understood. Based on data from Grey parrots (Psittacus erithacus), researchers proposed a correlation between contrafreeloading and play: that contrafreeloading is more likely when subjects view the task as play. We tested that hypothesis by subjecting a relatively more playful parrot species, the kea (Nestor notabilis), to the same experimental tasks. Experiment 1 presented eight kea with container pairs holding more- or less-preferred free or enclosed food items, and examined three types of contrafreeloading: calculated (working to access preferred food over less-preferred, freely available food); classic (working to access food identical to freely available food); and super (working to access less-preferred food over preferred, freely available food). At the group level, the kea behaved similarly to the Greys: They significantly preferred calculated contrafreeloading, performed classic contrafreeloading at chance, and significantly failed to super contrafreeload. However, overall kea engaged in more contrafreeloading than Greys. Experiment 2 examined a potentially more ecologically relevant task, a choice between shelled and unshelled walnuts. No kea contrafreeloaded for nuts, whereas two of five Greys significantly preferred nut contrafreeloading and one chose at chance. We examine proximate and adaptive explanations for the performances of these differentially playful parrot species to further elucidate the role of play in contrafreeloading.Peer reviewe
A modified primer-pair designed for the molecular sex identification of black-legged Kittiwake (Laridae: Rissa tridactyla)
Get PDFFunding: This study was funded under the Natural Environment Research Council Scottish Universities Partnership for Environmental Research Doctoral Training Partnership (NE/S007342/1, website https://superdtp.st-andrews.ac.uk/) with additional funding from the Marine Directorate (Scottish Government) and the Joint Nature Conservation Committee. Collection of Norwegian samples and data were financed by the SEAPOP program (www.seapop.no, grant no. 192141), and the Marine Alliance for Science and Technology Scotland and Scottish Funding Council Saltire Emerging Researcher Scheme (Ref. SERS1-10). Russian samples and data were supported by the ARCTOX and SEATRACK programmes. Dutch samples and data were collected in a collaborative project between Ruben Fijn, Rob van Bemmelen (both Waardenburg Ecology) and Hans Schekkerman (Sovon), which was commissioned by TotalEnergies (Thijs Kabel and Gerry van der Meijden).In studies of avian populations accurate sex identification facilitates the study of sex-linked behaviour, ecology, social structure, decision-making, and life histories. To improve molecular sex identification protocols for the black-legged kittiwake (Laridae: Rissa tridactyla, hereafter ‘kittiwake’), primers previously developed for other bird species were realigned against the kittiwake CHD1 Z and W chromosomes to generate a species-specific primer-pair. Amplicons of 602 bp and 375 bp were produced using typical PCR and gel electrophoresis procedures. The modified primer-pair was validated on a test sample of 138 kittiwakes from four Atlantic breeding colonies sexed a priori using head-bill length.Peer reviewe
Spatial capture-recapture can improve environmental impact assessments for large carnivores
Get PDFFunding: This manuscript forms part of the ongoing PhD research of Gonçalo Ferrão da Costa, titled ‘Large Carnivores in Space and Time—Understanding Wolf Dynamics through Non-Invasive Methodologies’, funded by the Fundação para a Ciência e Tecnologia (FCT, Portugal) under grant no. 2020.06403.BD (https://doi.org/10.54499/2020.06403.BD). Data collection for this analysis was supported by funding from Trustwind and BE–Bioinsight & Ecoa.1. Environmental Impact Assessments (EIAs) for large carnivores frequently rely on summary statistics or relative abundance indices to evaluate the effects of infrastructure development on predator populations. However, these approaches often fail to account for imperfect detection and observer bias, which can result in misleading conclusions about population status and trends. This leads to potentially unreliable conclusions and suboptimal conservation decisions. 2. This study addresses these limitations by demonstrating the benefits of spatial capture–recapture (SCR), particularly its capacity to account for detection probability and spatial heterogeneity, using the wolf (Canis lupus) as a model species in a 3-year monitoring programme within a windfarm-impacted landscape in Portugal. 3. We show that, aside from the addition of georeferenced individual identification and survey effort data, implementing SCR requires only minimal adjustments to existing survey designs while yielding substantial analytical benefits. SCR generates unbiased estimates of density, abundance and space use—critical metrics for assessing population status—and allows the integration of spatial covariates (such as proximity to infrastructure) to enable explicit, model-based inference about potential impacts. 4. Practical implications. Incorporating SCR into EIA monitoring can replace relative abundance indices with robust ecological metrics, enhancing transparency and reliability for stakeholders. This approach supports adaptive management procedures and the development of effective mitigation and compensation measures across project phases, ultimately promoting the long-term resilience of large carnivore populations.Peer reviewe
Kea (Nestor notabilis) fail a loose-string connectivity task
Get PDFFunding: This project was made possible through the support of a grant from Templeton World Charity Foundation (AHT), a Rutherford Discovery Fellowship (AHT), and a Prime Minister’s McDiarmid Emerging Scientist Prize (AHT).Naïve individuals of some bird species can rapidly solve vertical string-pulling tasks with virtually no errors. This has led to various hypotheses being proposed which suggest that birds mentally simulate the effects of their actions on strings. A competing embodied cognition hypothesis proposes that this behaviour is instead modulated by perceptual-motor feedback loops, where feedback of the reward moving closer acts as an internal motivator for functional behaviours, such as pull-stepping. To date, the kea parrot has produced some of the best performances of any bird species at string-pulling tasks. Here, we tested the predictions of the four leading hypotheses for the cognition underpinning bird string-pulling by presenting kea with a horizontal connectivity task where only one of two loose strings was connected to the reward, both before and after receiving perceptual-motor feedback experience. We find that kea fail the connectivity task both before and after perceptual-motor feedback experience, suggesting not only that kea do not mentally simulate their string-pulling actions, but also that perceptual-motor feedback alone is insufficient in eliciting successful performance in the horizontal connectivity task. This suggests a more complex interplay of cognitive factors underlies this iconic example of animal problem-solving.Peer reviewe
Heating and cooling at a coronal magnetic null
Get PDFAWH and DJ gratefully acknowledge the financial support of the Science and Technology Facilities Council (STFC) through Consolidated Grants ST/S000402/1 and ST/W001195/1 to the University of St Andrews.Conductive cooling of the solar corona at a magnetic null is examined. An initial equilibrium is set up, balancing thermal conduction and a constant spatially uniform coronal heating. The heating is then turned off and the subsequent conductive cooling calculated. An equation for the cooling is obtained using the method of separation of variables and it is shown that the equations for the equilibrium between conduction and heating, and the time-dependent cooling are mathematically identical with a simple change of variables. Thus, the properties of the cooling phase are automatically determined by the equilibrium state. For a two-dimensional null, the characteristic cooling time-scale increases over that in a straight field by a factor of between 2 and 5, with a scaling determined by the ratio of the average and base areas of a flux element. There is no explicit dependence on the very large areas that can arise near the null.Peer reviewe
The aesthetic constitution of genders
Get PDFThis paper presses the programmatic idea that it is fruitful to think of genders as constituted by aesthetic rational social practices; in particular, that doing so can illuminate the relation between social role and self-identity. The first part of the paper describes rational social practices, and then interprets two social-role approaches to genders in light of that description. The interpretation places the two approaches in different domains of reason, one epistemic, one practical; this makes apparent the conceptual space for a model of gender roles inhabiting the aesthetic domain. The second part of the paper articulates such a model, according to which the feminine and masculine roles in a social context consist in aesthetic constraints, enablements and norms. These depend on rational, social, human-centred aesthetic practices in which gender differentiation is essential. The third part of the paper demonstrates the utility of this model by using it to explore the relation between social role and self-identity; it argues that one identifies with a gender by actively participating in the very aesthetic practices that constitute it, and so generating reasons for self-valuation. Throughout, the point is not so much to defend the specific details of the suggested views, but more to show that the idea that aesthetic practices play a significant role in constituting gender merits serious consideration.Peer reviewe
How exploratory and selective developmental mechanisms generate facilitated variation and influence evolution, with a focus on the evolution of adaptive immunity
Get PDFPhenotypic plasticity is often conceptualized in two contrasting ways: as reaction norms that map specific environmental cues to phenotypic changes (a highly deterministic notion of plasticity) and more variable and experience-dependent forms of plasticity such as behavioural and cognitive adaptation (a.k.a. ‘exploratory mechanisms’). In practice, many plastic traits are likely to incorporate both inherited components that produce structured responses to environmental cues and flexible components that rely on environmental feedback, and these components of plasticity will frequently interact. For instance, innate immunity biases clonal selection in vertebrate adaptive immunity to ensure that common microbial threats are rapidly targeted and suppressed. Despite functioning in concert, innate and feedback-dependent forms of plasticity significantly differ in their inheritance and their impact on fitness, leaving their joint evolution subject to non-trivial trade-offs. Here I use a computational approach to investigate the evolution of forms of plasticity based on the iterative generation of superfluous phenotypic variation and subsequent selective reinforcement using environmental feedback. After a brief introduction to the topic (chapter 1) and discussion of a framework of assumptions (chapter 2), I go on to focus on the idea that variation and selection, when occurring within the lifetime of an organism rather than at the scale of generations and populations, may facilitate the evolution of an inherited bias in the variability of phenotypes (chapter 3). In chapter 4, I explore this idea further in the context of negative frequency-dependent selection. Finally, in chapter 5 and 6 I confine my analysis to adaptive immunity, conceptualised as a form of within-lifetime variation and selection. I find support for the hypothesis that adaptive immunity could have evolved to facilitate interactions with a diversity of beneficial and threatening microbes across co-evolutionary timescales. Together, this work illustrates how variability in the formation and reinforcement of phenotypes within lifetimes may influence long-term evolution."This thesis was supported by the University of St Andrews and funded by the DSTL French-UK PhD scheme."--Fundin
Mathilde Blind and Ludwig Mond : chemistry, industry, and waste in late-Victorian culture
Get PDFThis essay examines the friendship between the poet Mathilde Blind and the industrial chemist Ludwig Mond, arguing that Blind’s dialogue with Mond’s thinking about waste and productivity reveals surprising similarities between the concerns of Victorian industry and those of fin-de-siècle literary culture. Mond’s work was shaped by the productivist belief that industry, far from damaging the natural environment, exemplified humanity’s participation in a providential economy in which all waste, including industrial waste, could be recycled and again rendered productive. Blind found solace in this argument, refiguring it both to endorse the aestheticizing work of poetry and to support her speculations about personal immortality. But she was also sceptical of Mond’s productivism, and, especially in the notebook she used in the 1890s, voiced a concern that failure and waste could not be prevented entirely, whether by nature, the industrial nation, or the individual.Peer reviewe
Addressing degradation of Ni/YSZ cermet fuel electrode in reversible solid oxide cells
Get PDFFunding: This work was supported by the UK Engineering and Physical Sciences Research Council (EPSRC) under the project “High efficiency reversible solid oxide cells for the integration of offshore renewable energy using hydrogen – expertise and track record of the team” (Grant Number: EP/W003686/1). The research group at the Institute of Power Engineering – National Research Institute acknowledges the IPE-NRI statutory grant, “Development of Reversible Solid Oxide Cells (SOC) Based on the Institute of Power Engineering's Technology for Power-to-X Systems”, for the project running from 2022 to 2024). EPSRC grants EP/T019298/1 and EP/R023751/1 are also acknowledged.Ni cermet fuel electrodes yield excellent electrochemical performance in solid oxide cells (SOCs), but their long-term stability is hindered by degradation mechanisms related to Ni agglomeration. While microstructure engineering can slow this degradation, it remains an intrinsic issue. Here, a new approach is presented to mitigate this degradation through infiltration of cerium oxides. This study shows that adding nanostructured CGO reduces degradation and enhances stability in the reversible mode. Although some agglomerations is observed, it does not impact cell performance. CGO-infiltrated cells exhibited no signs of degradation over 650-hours in reversible mode at 750°C, alternating between high hydrogen concentration (97% H2 and 3% H2O) at 0.8 V and high steam concentration (10% H2 and 90% H2O) at 1.27 V. Generated current increased in FC mode (from 0.20 to 0.31 Acm−2) and from 0.39 to 0.65 Acm−2 in EC mode. In contrast, non-infiltrated cells showed a decline in EC mode from 0.67 to 0.2 A cm−2 and in FC mode from 0.49 to 0.31 Acm−2 after 400h. This offers a promising route to improving SOCs. Ni agglomeration's minor effect on electrochemical activity suggests the reaction has moved from the triple-phase boundary at the electrode gas interface to the double-phase boundary.Peer reviewe
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