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JWST-TST DREAMS : Sulfur dioxide in the atmosphere of the Neptune-mass planet HAT-P-26 b from NIRSpec G395H transmission spectroscopy
Get PDFFunding: L.A. is supported by Cornell University College of Arts & Sciences Klarman Fellowship. H.R.W. was funded by UK Research and Innovation (UKRI) framework under the UK government’s Horizon Europe funding guarantee for an ERC Starter Grant (grant No. EP/Y006313/1). R.J.M. is supported by NASA through the NASA Hubble Fellowship grant HST-HF2-51513.001, awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS 5-26555. D.R.L. acknowledges support from NASA under award No. 80GSFC24M0006. C.I.C. acknowledges support by NASA Headquarters through an appointment to the NASA Postdoctoral Program at the Goddard Space Flight Center, administered by ORAU through a contract with NASA.We present the James Webb Space Telescope (JWST) transmission spectrum of the exoplanet HAT-P-26 b (18.6 M⊕, 6.33 R⊕), based on a single transit observed with the JWST NIRSpec G395H grating. We detect water vapor (ln = 4.1), carbon dioxide (ln = 85.6), and sulfur dioxide (ln = 13.5) with high confidence, along with marginal indications for hydrogen sulfide and carbon monoxide (ln < 0.5). The detection of SO2 in a warm super-Neptune-sized exoplanet (RP ∼ 6 R⊕) bridges the gap between previous detections in hot Jupiters and sub-Neptunes, highlighting the role of disequilibrium photochemistry across a broad range of exoplanet atmospheres, including those cooler than 1000 K. Our precise measurements of carbon, oxygen, and sulfur indicate an atmospheric metallicity of ∼10× solar and a subsolar C/O ratio. Retrieved molecular abundances are consistent within 2σ with predictions from self-consistent models including photochemistry. The elevated CO2 abundance and possible H2S signal may also reflect sensitivities to the thermal structure, cloud properties, or additional disequilibrium processes such as vertical mixing. We compare the SO2 abundance in HAT-P-26 b with that of 10 other JWST-observed giant exoplanets, and find a correlation with atmospheric metallicity. The trend is consistent with the prediction from I. J. M. Crossfield, showing a steep rise in SO2 abundance at low metallicities, and a more gradual increase beyond 30× solar. This work is part of a series of studies by our JWST Telescope Scientist Team (JWST-TST), in which we use Guaranteed Time Observations to perform Deep Reconnaissance of Exoplanet Atmospheres through Multi-instrument Spectroscopy (DREAMS).Peer reviewe
Sleep disturbance in children with prenatal alcohol exposure : a systematic review and meta-analysis
Get PDFBackground: Sleep disturbances are prevalent in children with prenatal alcohol exposure (PAE), including those with Fetal Alcohol Spectrum Disorders (FASD), potentially exacerbating behavioural and cognitive deficits. Despite this, no review has systematically assessed the timing or severity of these sleep disturbances. The aim of this review was to identify sleep disturbances in children with PAE. Methods: A systematic search across seven databases followed PRISMA guidelines. Studies included children aged 3–10 with PAE and provided quantitative sleep data. Two reviewers independently screened articles. A meta-analysis of subjective sleep outcomes used a random-effects model, with heterogeneity assessed via I2. Results: Fourteen studies met inclusion criteria. Children with PAE had consistently worse sleep than typically developing peers, including longer sleep onset, shorter duration, more awakenings, lower sleep efficiency, and greater sleep variability. Higher PAE levels were linked to earlier onset and persistence of sleep disturbances, with more severe issues in early pregnancy exposure. Meta-analysis of seven studies showed high heterogeneity (I2 = 0.91) with medium to large effect sizes, particularly for night awakenings (d = 1.04) and sleep duration (d = 0.89). Conclusions: Children with PAE face persistent sleep disturbances, worsening with heavier or earlier exposure, highlighting the need for early screening and interventions.Peer reviewe
Spontaneous encoding of event roles in hominids
Get PDFFunding: This research was funded by the Swiss National Science Foundation (project grant numbers 310030_185324, KZ, and 100015_182845, BB) and the National Center for Competence in Research “Evolving Language” (SNSF agreement number 51NF40_180888, BB, KZ).When observing social interactions, humans rapidly and spontaneously encode events in terms of agents, patients and causal relations. This propensity can be made visible empirically with the switch cost paradigm, a reaction time experiment and well-established tool of cognitive psychology. We adapted the paradigm for non-human primates to test whether non-linguistic animals encoded event roles in the same way. Both human and non-human participants were requested to attend to different social interactions between two artificially coloured (blue or green) actors and to target the actor masked by a specified colour (e.g., blue), regardless of her role. We found that when we switched the targeted colour mask from agents to patients (or vice versa) the processing time significantly increased in both hominid species (i.e., human and chimpanzee), suggesting that event roles were spontaneously encoded and subsequently interfered with our simplistic colour search task. We concluded that the propensity to encode social events in terms of agents and patients was a common feature of hominid cognition, as demonstrated in several human and one chimpanzee participant, pointing towards an evolutionarily old and phylogenetically shared cognitive mechanism central to language processing.Peer reviewe
Emotional drivers of pedagogy and their place in the motivational process : distinguishing percepts from outcomes
Get PDFFunding: The author(s) declare that financial support was received for the research and/or publication of this article. This research was supported by a studentship at the Scottish Graduate School of Social Science (award number ES/P000681/1), which was funded by the Economic and Social Research Council (ESRC) and the Scottish Funding Council (SFC).Introduction: Research examining teachers’ experiences during the Covid pandemic highlighted the importance of emotion as a driver of motivation, specifically the emotions of CARE, CURIOSITY, COOPERATION and CHALLENGE. Here we examine the generalisability of those findings in the post-pandemic period. Methods: Interviews were carried out with a new cohort of nine Scottish teachers, and deductive thematic and narrative analyses were used to analyse the data. Results: Results confirmed the presence of the four motivating emotions, as distinct from outcome emotions such as pride and frustration. However, their prevalence shifted, with CARE and CURIOSITY less dominant than during Covid, while CHALLENGE was more prevalent. Teachers’ accounts also suggested that COMMUNITY is a more accurate label than COOPERATION for capturing the feelings associated with shared social motivation. Examination of co-occurrence of emotions showed they were frequently mentioned in close temporal proximity to each other. Narrative analysis highlighted individual stories that link emotional percepts, cognitions, volitional behaviour, and outcome emotions within each teacher’s situational context. We consequently propose a motivational process model consisting of these four factors, in contrast to a recent integrative framework including six stages of action in which emotions are less foregrounded. Discussion: We discuss how these findings support the development of a Theory of Emotionally Motivated Pedagogy that presents emotions as a central component of teacher motivation. Implications are discussed for pedagogical practitioners seeking to understand their own motivation, as well as for researchers examining motivation as a complex affectivist phenomenon.Peer reviewe
Quantitative covering and equidistribution
Get PDFFunding: This work was partly funded by a Leverhulme ECR fellowship ECF-2021-385.Covering (density of orbits) and equidistribution are fundamental properties of an ergodic dynamical system. In this expository note, we investigate the quantitative aspects of these properties for a simple model. In particular, we investigate how much of a single orbit we must observe before we can expect it to reach a certain density in the state space and for it to be almost equidistributed, in a certain sense. We explore more broadly how these questions regarding the statistics of individual dynamical orbits are closely related to the multifractal properties of the underlying ergodic measure.Peer reviewe
Development and innovation in a new distributed medical programme : Scottish Graduate Entry Medicine (ScotGEM)
Get PDFFunding: The author(s) declare that financial support was received for the research and/or publication of this article. We thank the University of Dundee for funding the article processing charge.Introduction: Addressing the shortage of primary-care physicians, especially in remote and rural areas, is a crucial target in many countries. This article introduces the Scottish Graduate Entry Medicine (ScotGEM) programme: a compressed, tailor-made curriculum designed to equip and enthuse its graduates to practice generalist and rural medicine in Scotland, within the ethos of socially accountable medicine. Methods: This curriculum paper describes ScotGEM in sufficient detail for the reader to translate elements to their own context. It then collates findings from evaluations, research projects and many critical discussions about the programme. This work is used to describe and evaluate the curriculum design and delivery, with a focus on the distributed aspects. Results: Three key innovations of the curriculum are explored in detail: the Generalist Clinical Mentor (GCM) role; the year-long primary care Longitudinal Integrated Clerkship (LIC); and the Agents of Change curriculum. There are early signs that ScotGEM is encouraging generalist, rural careers within Scotland. There is also growing evidence of the benefits ScotGEM faculty and students bring to the clinical workforce in the distributed settings. Discussion: Distributed programmes require additional organization for students and faculty. Partnerships can be challenging but immensely rewarding. Healthcare partners in rural areas need to be involved early in planning and strong relationships fostered with local “champions.”Peer reviewe
The Future of (Environmental) History: A Roundtable Discussion
Get PDFFunding: The workshop behind this roundtable was made possible by generous funding from the Royal Historical Society.In April 2023, eighteen scholars from nine different subjects representing the humanities, natural and social sciences came together for a one-day workshop at St John’s College, Durham. Despite our differences, all had one aim: the study of past environmental change and its effects on human societies. Talking across disciplinary divides, we discussed what environmental history is, how it may or may not contribute to tackling the climate crisis, and the problems of sources, scale and temporality. This article collects select conversations into a roundtable format split into four areas: scale, time and space, interdisciplinarity, and the future of environmental history. We argue that environmental history is more usefully understood not as a distinct sub-field of history, but as an interdisciplinary meeting place for innovative collaboration. This also presents a model for future research aimed at tackling the climate crisis at higher education institutions.Peer reviewe
An account on structure, synthesis and application of polythiophene and swelling behaviour of non-conducting polymers
Get PDFPolymer matrixes are studied extensively due to their unique chemical and mechanical properties and a wide field of applications. Conducting polymers are utilized as the active materials for solid-state devices viz. batteries, LED and sensors. The present article discusses the application of polythiophene as an active material for energy active devices. In addition, the authors have worked on enhancing the ionic conduction of non-conducting polymers like poly[ethylene oxide]. Solvent diffusion mechanism of non-conducting polymer–salt composite is nonlinear in nature. Swelling tendency of polymer composite can be influenced to physical, chemical and morphological behaviour. Ionic conductivity phenomena of polymer–salt composite are also influenced by the solvent
Machine-learning approach to understanding ultrafast carrier dynamics in the three-dimensional Brillouin zone of PtBi2
Get PDFFunding: This work was supported by the Independent Research Fund Denmark (Grants No. 1026-00089B and No. 4258-00002B) and Novo Nordisk Foundation (Grant No. NFF23OC0085585). S.A. acknowledges DFG through AS 523/4-1.Using time- and angle-resolved photoemission spectroscopy, we examine the unoccupied electronic structure and electron dynamics of the type-I Weyl semimetal PtBi2. Using the ability to change the probe photon energy over a wide range, we identify the predicted Weyl points in the unoccupied three-dimensional band structure and we discuss the effect of k⊥ broadening in the normally unoccupied states. We characterize the electron dynamics close to the Weyl points and in other parts of three-dimensional Brillouin zone using k-means, an unsupervised machine-learning technique. This reveals distinct differences—in particular, that the electron dynamics close to the Weyl points are slower than in Brillouin zone regions close to the bulk Fermi surface.Peer reviewe
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