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Foraging behaviour of nesting Grey Herons inferred from PIT-tagged salmonid fish
No full textStudies of fish behaviour and ecology create opportunities for studying piscivores that have been underutilised. A leading example is the widespread use by fish biologists of Passive Integrated Transponder (PIT) tagging for identifying individuals, tracking movements, and estimating population sizes. PIT tags have high physical durability and long electronic lifespans. In consequence, if a piscivore swallows a tagged fish, the tag will almost certainly be excreted intact and subsequently detectable at the location of excretion for years. Accessible nesting or roosting colonies of piscivorous birds adjacent to fish PIT-tagging study sites thus present a potentially rich source of information on feeding habits. However, when such PIT tag surveys are conducted, they typically focus on the biology of the prey and not the predator. Here, we make opportunistic use of a PIT-tagging study of young Salmo spp. salmonids in Ireland to investigate the biology of a widespread and familiar avian piscivore, the Grey Heron Ardea cinerea. We scanned the ground underneath an accessible heronry for tags known to have been fitted to their carriers over four days in May 2019 in an intensively monitored river from which emigration is only possible via a fish trap. We found 48 focal tags in the heronry out of 594 tagged fish. Tags in the heronry were significantly biased towards smaller individuals and S. salar. Data on unpredated fish implies that all putative predation events occurred at least 10.8 km from the heronry despite there being foraging habitat less than 150 m from the colony, and that the majority occurred before the end of June in the year of tagging. We discuss our results in the context of the relatively limited information on breeding-season foraging activity for Grey Herons, optimal foraging considerations and ways to refine the use of PIT tagging of fish for studying piscivores
Erratum: “Self-consistent 3D Radiative Transfer for Kilonovae: Directional Spectra from Merger Simulations” (2023, ApJL, 954, L41)
No full textAfter the article was published, we discovered an error in our conversion of log gf values to A values from the Kurucz atomic data set. A “wavelength” column was erroneously interpreted to have units of angstroms instead of nanometers, which (when squared) resulted in A values that were too high by a factor of 100. In particular, this affected the A values of Sr, Y, and Zr for the “AD2” data set. The wavelengths of the transitions were not affected, since these were separately calculated from the differences between energy levels that were correctly interpreted. An erroneous multiplicative factor was also found in the free–free opacities, leading to an upward revised bolometric luminosity at the early times (≲0.5 days), before the free–free opacity becomes negligible. The conclusions of the Letter are not affected by these errors, although there are quantitative differences. The times at which our 3D AD2 modeled spectra appear similar to AT2017gfo (which were already too ea rly) are shifted later by around 0.3 days. Therefore, we present new versions of the figures with updated models at the corrected times in Figures 1, 2, 3, 4, and 5. (Figure presented).</p
The famine that wasn't? Ireland, 1799–1801
No full textThis paper re-examines the period of potential famine in Ireland between 1799 and 1801, reframing it as the “Famine that Wasn't.” Although successive harvest failures occurred during these years—back-to-back crop failures in 1799 and 1800—famine conditions did not follow. The study critically investigates how Ireland avoided mass starvation despite these climatic and agricultural challenges in a period better known for constitutional change, notably the Act of Union between Britain and Ireland which came into effect in January 1801. The broad conclusion reached is that while immediate food shortages and social distress were evident, famine was averted in 1800 and 1801 due to a combination of favourable political, ideological and social circumstances, timely state interventions, flexible relations of production, some scattered instances of organised philanthropy, and a widespread ethic of sharing. Acting in conjunction, these served to limit excess mortality. The Irish would not be so fortunate a half century later. Of theoretical interest to economists and economic anthropologists, the paper argues that in pre-industrial economies spikes in food prices may be poor indicators of the extent of distress and excess mortality.<br/
Unmasking the self: exploring autistic adolescents' experiences of drama and its impact on wellbeing
No full textPulmonary endpoints in clinical trials for children with cystic fibrosis under two years of age - a European consensus
No full textCystic fibrosis is a lifelong progressive disease and the earlier that treatment can be initiated the better are the long-term outcomes. However, in children under 2 years of age there are challenges in choosing clinical trial endpoints that are both relevant and feasible. Many authorisation studies to date in this age group have extrapolated pulmonary efficacy from older age groups, with a focus on safety, pharmacokinetics, and biomarker response. As lung health is normal or near normal in this age group demonstrating lack of pulmonary decline may require prohibitively large numbers for standard duration regulatory studies. The European Cystic Fibrosis Society Clinical Trial Network was approached to produce a consensus document evaluating direct pulmonary endpoints as well as biomarkers and non-pulmonary endpoints relevant for pulmonary therapies in this age group. Endpoints evaluated are multiple-breath washout (MBW); chest CT; chest MRI; airway infection and inflammation; gastrointestinal parameters; pharmacodynamic measurement of cystic fibrosis transmembrane regulator (CFTR) protein function; and patient-reported outcome measures. Currently, design for trials for young children with cystic fibrosis under 2 years of age should usually continue to study pharmacokinetics, pharmacodynamics where appropriate, safety and tolerability as the primary endpoints, but should include pulmonary and non-pulmonary endpoints as secondary or exploratory outcomes. Long term post authorization studies exploring pulmonary outcome measures such as MBW, measures of structural lung disease such as CT and MRI, and measures of pulmonary inflammation will be vital to help us understand the pulmonary benefit of commencing therapies in this young cohort.<br/
TMAN: A Triple Morphological Feature Attention Network for Fine-Grained Classification of Breast Ultrasound Images
No full textAccurately diagnosing various types of breast lesions is critical for assessing breast cancer risk and predicting patient outcomes, which necessitates a fine-grained classification approach. While convolutional neural networks (CNNs) are predominantly employed in fine-grained classification tasks for breast lesions, they often struggle to effectively capture and model the intricate relationships between local and global features, an aspect that is vital for achieving high classification accuracy. Additionally, Color Doppler Flow Imaging (CDFI) and Strain Elastography (SE) are two important ultrasound imaging techniques widely used in the diagnosis of breast lesions. However, their specific contributions to fine-grained classification have not been thoroughly investigated. In this paper, we introduce a Triple Morphological Feature Attention Network (TMAN) designed to enhance fine-grained classification of breast ultrasound images. The TMAN architecture comprises three key modules: Local Margin Attention (LMA), Structured Texture Attention (STA), and Fusion Attention (FA), each focused on extracting distinct morphological features. TMAN achieved an average accuracy of 74.40%, precision of 73.18%, and specificity of 96.02%, surpassing state-of-the-art methods. The findings reveal that incorporating CDFI significantly improved classification for malignant subtypes with a 10% accuracy boost, while SE had a negligible impact. These findings highlight the effectiveness of TMAN in extracting nuanced morphological features and advancing precision in breast ultrasound diagnosis. The source code is accessible at https://github.com/windywindyw/TMAN
Book Review: Towards Abolitionist Futures? ‘The End of Peacekeeping. Gender, Race and the Martial Politics of Intervention’, University of Pennsylvania Press: Philadelphia, PA, 2024, 208 pp. ISBN: 9781512825237
No full textHigh electrical power experimental methods to de-risk integrated electrical and carbon fibre composite structure design
No full textElectrification is a key enabling technology for decarbonisation of flight. However, the associated weight of these systems is a major design challenge. Opportunities for weight reduction exist through the integration of the electrical power system with carbon fibre composite (CFC) structures i.e. non-electrically active CFC components in electrical power equipment and minimisation of cable harnesses. However, these new integrated systems introduce new failure modes when CFC, which normally exhibit dielectric behaviours, conduct electrical fault currents. To understand these challenges, the associated material behaviours, including time-variant electrical-thermal behaviour of CFC, must be fully characterised.Pre-existing experimental methods are limited to lower power levels by existing power supply current and voltage limits. While these studies indicate that glass transition temperature is reached, behaviour prediction at higher power levels is reliant on extrapolation and modelling. Therefore, this paper will present an experimental methodology to capture electrical-thermal response of CFC at aircraft high voltage levels. A capacitive discharge rig is used to control the applied voltage level and electrical fault duration, without current limitation. The paper will explore the ability of both experiments and modelling to replicate the electrical-thermal response of CFC within modern aircraft electrical power system models, thus directly de-risking integrated systems design
On the use of the Axelrod formula for thermal electron collisions in astrophysical modelling
No full textThe Axelrod approximation is widely used in astrophysical modelling codes to evaluate electron-impact excitation effective collision strengths for forbidden transitions. Approximate methods such as this are a necessity for many heavy elements with open shells where collisional data is either non existent or sparse as the use of more robust methods prove prohibitively expensive. Atomic data for such forbidden transitions are essential for producing full collisional radiative models that do not assume Local-Thermodynamic-Equilibrium (LTE). In this short work we present the re-optimization the simple Axelrod formula for a large number of R-matrix data sets, ranging from Fe and Ni to the first r-process peak elements of Sr, Y and Zr, to higher Z systems Te, W, Pt and Au. We show that the approximate treatment of forbidden transitions can be a significant source of inaccuracy in such collisional radiative models. We find a large variance of the optimized coefficients for differing systems and charge states, although some general trends can be seen based on the orbital structure of the ground-state-configurations. These trends could potentially inform better estimates for future calculations for elements where R-matrix data is not available.<br/