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Chancellors and the legacies of Empire at St Andrews, 1700-1900
No full textThis working paper reports the result of an audit on the 8 men who held the role of Chancellor at St Andrews between 1700 and 1900. It was presented to the Legacies of Empire steering group in March 2023 to inform discussion about whether to include the Chancellors in the project Report. This working paper contains slightly more information than was ultimately included in ‘Section 4.6: the Chancellors’ in the final report on St Andrews and the Legacies of Empire (2024)
Behind the scenes of Philosophical Transactions
No full textTo celebrate 360 years since the first publication of the Philosophical Transactions, Aileen Fyfe invites you behind the scenes of the making of a scientific periodical
The social burden of antimicrobial resistance:what is it, how can we measure it, and why does it matter?
No full textAntimicrobial resistance (AMR) is a growing global health threat, which is increasingly quantified in terms of its human health and economic burden. In this article, we highlight that for policy and planning purposes the social burden of AMR is as important to attend to as health and economic burdens, requiring systematic consideration and measurement of multiple dimensions. We provide a conceptual and empirical overview of four dimensions of the social burden of AMR: the distribution of AMR among and between populations; the lived experiences of AMR by patients and carers; how and by whom AMR interventions are shouldered; and how AMR can change society. We illustrate these dimensions through five case studies drawn from research projects in the UK, East Africa, Thailand and Brazil. Drawing on these insights, we discuss challenges and opportunities for documentation and measurement of AMR’s social burden going forward. Taking this seriously aligns with the consensus observation that to address AMR requires moving away from pathogen-based and siloed disciplinary perspectives and means embracing different forms of data and evidence from around the world. We propose an interdisciplinary engagement across researchers, policy makers and community stakeholders to arrive at agreed principles and metrics for future monitoring of the social burden. We need to tackle invisibility through lack of data by considering the social burden in design of AMR surveillance and research, includes mainstreaming social science data, and incorporating arts-based approaches to understanding AMR. Recognition, documentation and measurement of the social burdens of AMR will advance AMR approaches and help develop equitable solutions
Magnetic fields in massive star-forming regions (MagMaR):the magnetic field at the onset of high-mass star formation
No full textA complete understanding of the initial conditions of high-mass star formation and what processes determine multiplicity requires the study of the magnetic field in young massive cores. Using Atacama Large Millimeter/submillimeter Array (ALMA) 250 GHz polarization observations (0."3 = 1000 au) and ALMA 220 GHz high-angular-resolution observations (0."05 = 160 au), we have performed a full energy analysis including the magnetic field at core scales and have assessed what influences the multiplicity inside a massive core previously believed to be in the prestellar phase. With a mass of 31 M⊙, the G11.92 MM2 core has a young CS molecular outflow with a dynamical timescale of a few thousand years. At high resolution, the MM2 core fragments into a binary system, with a projected separation of 505 au and a binary mass ratio of 1.14. Using the Davis–Chandrasekhar–Fermi method with an angle dispersion function analysis, we estimate in this core a magnetic field strength of 6.2 mG and a mass-to-magnetic-flux ratio of 18. The MM2 core is strongly subvirialized, with a virial parameter of 0.064, including the magnetic field. The high mass-to-magnetic-flux ratio and low virial parameter indicate that this massive core is very likely undergoing runaway collapse, which is in direct contradiction with the core accretion model. The MM2 core is embedded in a filament that has a velocity gradient consistent with infall. In line with clump-fed scenarios, the core can grow in mass at a rate of 1.9–5.6 × 10−4 M⊙ yr−1. In spite of the magnetic field having only a minor contribution to the total energy budget at core scales (a few thousands of astronomical units), it likely plays a more important role at smaller scales (a few hundreds of astronomical units) by setting the binary properties. Considering energy ratios and a fragmentation criterion at the core scale, the binary system could have been formed by core fragmentation. The binary system properties (projected separation and mass ratio), however, are also consistent with radiation-magnetohydrodynamic simulations with super-Alfvenic or supersonic (or sonic) turbulence that form binaries by disk fragmentation.<div/
Enhancing the performance of metal-supported solid oxide fuel cells via infiltration with an aqueous solution of metal nitrate salts
No full textThe infiltration technique is a cost-effective method to develop nanostructured electrodes that can accelerate sluggish oxygen reduction reaction (ORR) and enhance the electrochemical performance of solid oxide fuel cells (SOFCs) at intermediate temperatures (600–800 °C). For metal-supported SOFCs, identifying a highly efficient ORR catalyst is an ongoing challenge due to lower temperature operation. In this work, nanostructured praseodymium oxide (PrOx) and multiphase heterostructures containing perovskites with the nominal composition of Nd0.6Sr0.4CoO3−δ (NSC), SrCO3, and CoO have been developed via infiltration into the symmetric metal-supported backbone as binary layer composite, and their electrochemical performance has been investigated. The composite demonstrates enhanced electrochemical performance at various temperatures achieving the lowest polarization resistance (Rp) of 0.05 Ω cm2 at 700 °C compared to multiphase NSC alone (0.1 Ω cm2) under similar conditions. A distribution function of relaxation time (DFRT) analysis using impedance spectroscopy genetic program (ISGP) was carried out to study different electrochemical processes. PrOx significantly improves the processes involved in the ORR. The full cell performance of the composite electrode achieves a peak power density (PPD) of 329 mW·cm–2 at 700 °C in 3%H2O/H2 as fuel
Representations of extensions of simple groups
No full textFeit and Tits (1978) proved that a nontrivial projective representation of minimal dimension of a finite extension of a finite nonabelian simple group G factors through a projective representation of G, except for some groups of Lie type in characteristic 2; the exact exceptions for G were determined by Kleidman and Liebeck (1989). We generalise this result in two ways. First we consider all low-dimensional projective representations, not just those of minimal dimension. Second we consider all characteristically simple groups, not just simple groups
Acoustic characteristics and context of buzzes and rasps produced by northern bottlenose whales (<i>Hyperoodon ampullatus</i>)
No full textDeep-diving northern bottlenose whales (Hyperoodon ampullatus) rely on sound for orientation, foraging and communication. While their regular echolocation clicks have been described, characterisations of other click types are limited. Here we quantify acoustic and behavioural differences between two types of rapid click trains: buzzes and rasps. Sound and movement data were collected from 15 animal-attached DTag deployments around Jan Mayen Island (Norway) from 2013–2016. Buzzes and rasps were manually identified, and random forest analyses revealed a classification accuracy of 93.7% (n = 129 respectively). Rasps occurred more often near the surface whereas buzzes were primarily emitted at depth during foraging dives, had shorter inter-click-intervals (U = 263, p < 0.001), longer durations (U = 14413, p < 0.001), and coincided with increased movement more often than rasps (U = 10384, p < 0.001). On-axis clicks from nearby whales showed further differences in duration and frequency content between individual buzz and rasp clicks. Our findings demonstrate that buzzes and rasps are acoustically and contextually distinct, with buzzes associated with foraging and rasps with communication. These differences will allow identification of buzzes and rasps and inference of behaviour and habitat use in passive acoustic data, enhancing research on this cryptic beaked whale
Magnetic x-ray spectroscopy of Gd-doped EuO thin films
No full textWe present a detailed x-ray magnetic circular dichroism (XMCD) study of the magnetic properties of Gd-doped EuO thin films, synthesized via molecular-beam epitaxy with Gd doping levels up to over 12%. The impact of Gd doping on the electronic and magnetic behavior of EuO is studied using XMCD and magnetometry. Gd doping significantly enhances the Curie temperature (C) from 69 K in undoped EuO to over 120 K, driven by increased carrier density, while preserving the high quality of the single-crystalline films. At higher doping levels, a plateau in C is observed, which is attributed to the formation of Eu-Gd nearest-neighbor pairs that limit dopant activation. We also observe a distinctive “double-dome” structure in the temperature-dependent magnetization, which we attribute to both the ferromagnetic ordering of Eu 4 moments at lower temperatures and the influence of conduction electrons via 4−5 exchange interactions at higher temperatures. These findings provide key insights into the mechanisms of carrier-induced magnetic transitions
Poloidal field line resonances driven by a fast wave
No full textWe present numerical simulations of the excitation of resonant poloidal Alfvén waves. The resulting Alfvén waves could be loosely described as “high‐m” (m is the azimuthal wave number) in as much as the azimuthal scale of the wave is much less than the scale in the direction normal to L‐shells. Such waves are generally excited by wave‐particle interactions. In this article we show how resonant poloidal Alfvén waves can be excited by a fast mode (of large azimuthal scale) in a cold plasma. The key property that enables this is a three‐dimensional equilibrium, which facilitates the process of phasemixing in the azimuthal direction. We show that the classification of resonant Alfvén waves as high‐m and low‐m has limited applicability in 3D inhomogeneous media and suggest an alternative classification be based on the excitation mechanism
Spatial proteomics identifies a CRTC-dependent viral signaling pathway that stimulates production of interleukin-11
No full textAppropriate cellular recognition of viruses is essential for the generation of an effective innate and adaptive immune response. Viral sensors and their downstream signaling components thus provide a crucial first line of host defense. Many of them exhibit subcellular relocalization upon activation, resulting in the expression of interferon and antiviral genes. To comprehensively identify signaling factors, we analyzed protein relocalization on a global scale during viral infection. cAMP-responsive element-binding protein (CREB)-regulated transcription coactivators 2 and 3 (CRTC2/3) exhibited early cytoplasmic-to-nuclear translocation upon infection with multiple viruses in diverse cell types. This movement was dependent on mitochondrial antiviral signaling protein (MAVS), cyclo-oxygenase proteins, and protein kinase A. A key effect of CRTC2/3 translocation is transcription of the fibro-inflammatory cytokine interleukin (IL)-11. This may be important clinically in viral infections associated with fibrosis, including SARS-CoV-2. Nuclear translocation of CRTC2/3 is, therefore, identified as an important pathway in the context of viral infection.</p