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exoALMA. IV. Substructures, asymmetries, and the faint outer disk in continuum emission
No full textFunding: P.C. acknowledges support by the Italian Ministero dell’Istruzione, Università e Ricerca through the grant Progetti Premiali 2012-iALMA (CUP C52I13000140001) and by the ANID BASAL project FB210003. S.F. is funded by the European Union (ERC, UNVEIL, 101076613), and acknowledges financial contribution from PRIN-MUR 2022YP5ACE. J.B. acknowledges support from NASA XRP grant No. 80NSSC23K1312. M.B., D.F., J.S, and A.W. have received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation program (PROTOPLANETS, grant agreement No. 101002188). M.F. has received funding from the European Research Council (ERC) under the European Unions Horizon 2020 research and innovation program (grant agreement No. 757957). M.F. is supported by a grant-in-aid from the Japan Society for the Promotion of Science (KAKENHI: No. JP22H01274). C.H. acknowledges support from NSF AAG grant No. 2407679. J.D.I. acknowledges support from an STFC Ernest Rutherford Fellowship (ST/W004119/1) and a University Academic Fellowship from the University of Leeds. A.I. acknowledges support from the National Aeronautics and Space Administration under grant No. 80NSSC18K0828. Support for A.F.I. was provided by NASA through the NASA Hubble Fellowship grant No. HST-HF2-51532.001-A awarded by the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. G.L. has received funding from the European Research Council (ERC) under the European Union Horizon 2020 research and innovation program (Grant agreement no. 815559 (MHDiscs)). G.L. and C.L. have received funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No. 823823 (DUSTBUSTERS). C.L. acknowledges support from the UK Science and Technology Research Council (STFC) via the consolidated grant ST/W000997/1. C.P. acknowledges Australian Research Council funding via FT170100040, DP18010423, DP220103767, and DP240103290. D.P. acknowledges Australian Research Council funding via DP18010423, DP220103767, and DP240103290. G.R. acknowledges funding from the Fondazione Cariplo, grant No. 2022-1217, and the European Research Council (ERC) under the European Union’s Horizon Europe Research & Innovation Programme under grant agreement No. 101039651 (DiscEvol). F.M. received funding from the European Research Council (ERC) under the European Union’s Horizon Europe research and innovation program (grant agreement No. 101053020, project Dust2Planets). N.C. has received funding from the European Research Council (ERC) under the European Union Horizon Europe research and innovation program (grant agreement No. 101042275, project Stellar-MADE). L.T. acknowledges funding from Progetti Premiali 2012 iALMA (CUP C52I13000140001), Deutsche Forschungs-gemeinschaft (German Research Foundation) reference No. 325594231 FOR 2634/1 TE 1024/1-1, European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant No. 823823 (DUSTBUSTERS), and the ERC via the ERC Synergy grant ECOGAL (grant No. 855130). T.C.Y. acknowledges support by Grant-in-Aid for JSPS Fellows JP23KJ1008. H.-W.Y. acknowledges support from the National Science and Technology Council (NSTC) in Taiwan through grant NSTC 113-2112-M-001-035- and from the Academia Sinica Career Development Award (AS-CDA-111-M03). G.W.F. acknowledges support from the European Research Council (ERC) under the European Union Horizon 2020 research and innovation program (grant agreement No. 815559 (MHDiscs)). G.W.F. was granted access to the HPC resources of IDRIS under the allocation A0120402231 made by GENCI. Support for B.Z. was provided by The Brinson Foundation.The exoALMA Large Program targeted a sample of 15 disks to study gas dynamics within these systems, and these observations simultaneously produced continuum data at 0.9 mm (331.6 GHz) with exceptional surface brightness sensitivity at high angular resolution. To provide a robust characterization of the observed substructures, we performed a visibility space analysis of the continuum emission from the exoALMA data, characterizing axisymmetric substructures and nonaxisymmetric residuals obtained by subtracting an axisymmetric model from the observed data. We defined a nonaxisymmetry index and found that the most asymmetric disks predominantly show an inner cavity and consistently present higher values of mass accretion rate and near-infrared excess. This suggests a connection between outer disk dust substructures and inner disk properties. The depth of the data allowed us to describe the azimuthally averaged continuum emission in the outer disk, revealing that larger disks (both in dust and gas) in our sample tend to be gradually tapered compared to the sharper outer edge of more compact sources. Additionally, the data quality revealed peculiar features in various sources, such as shadows, inner disk offsets, tentative external substructures, and a possible dust cavity wall.Peer reviewe
Constraining lens masses in moderately to highly magnified microlensing events from Gaia
No full textFunding: This project has received funding from the European Union’s Horizon Europe Research and Innovation programme ACME under grant agreement No 101131928 (2024-2028). ZTF is supported by the National Science Foundation under Grants No. AST-1440341 and AST-2034437. This work was partially funded by Kepler/K2 grant J1944/80NSSC19K0112 and HST GO-15889, and STFC grants ST/T000198/1 and ST/S006109/1. YT acknowledges the support of DFG priority program SPP 1992 "Exploring the Diversity of Extrasolar Planets" (TS 356/3-1). RAS and EB gratefully acknowledge support from the NASA XRP Program, through grant number 80NSSC19K0291. The Omega Key Project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No. 101004719 (OPTICON - RadioNet Pilot). This work is supported by the Polish MNiSW grant DIR/WK/2018/12. Josep Manel Carrasco work was (partially) supported by the Spanish MICIN/AEI/10.13039/501100011033 and by ”ERDF A way of making Europe” by the ”European Union” through grant PID2021-122842OB-C21, and the Institute of Cosmos Sciences University of Barcelona (ICCUB, Unidad de Excelencia ”María de Maeztu”) through grant CEX2019-000918-M and the project 2021-SGR-00679 GRC de l’Agència de Gestió d’Ajuts Universitaris i de Recerca (Generalitat de Catalunya). G.D., M.S. and M.D.J acknowledge support by the Astronomical Station Vidojevica and the Ministry of Science, Technological Development and Innovation of the Republic of Serbia (MSTDIRS) through contract no. 451-03-136/2025-03/200002 made with Astronomical Observatory (Belgrade), by the EC through project BELISSIMA (call FP7-REGPOT-2010-5, No. 256772), the observing and financial grant support from the Institute of Astronomy and Rozhen NAO BAS through the bilateral SANU-BAN joint research project "GAIA astrometry and fast variable astronomical objects", and support by the SANU project F-187. Also, this research was supported by the Science Fund of the Republic of Serbia, grant no. 6775, Urban Observatory of Belgrade - UrbObsBel. T.G. and the IST60 Telescope has been supported by the Scientific Research Projects Coordination Unit of Istanbul University (Project No.: TSG-2023-40046 and FBG-2017-23943) Turkish Republic, Directorate of Presidential Strategy and Budget project, 2016K121370. This work is partially supported by the Fundamental Fund of Thailand Science Research and Innovation (TSRI) through the National Astronomical Research Institute of Thailand (Public Organization) (FFB680072/0269). J.Z. and E.P. acknowledge funding from the Research Council of Lithuania (LMTLT, grant No. S-LL-24-1).Context . Microlensing events provide a unique way to detect and measure the masses of isolated, non-luminous objects, particularly dark stellar remnants. Under certain conditions, it is possible to measure the mass of these objects using photometry alone, specifically when a microlensing light curve displays a finite source (FS) effect. This effect generally occurs in highly magnified light curves, i.e. when the source and the lens are very well aligned. Aims . In this study, we analyse Gaia Alerts and Gaia Data Release 3 datasets, identifying four moderate-to-high-magnification microlensing events without a discernible FS effect. The absence of this effect suggests a large Einstein radius, implying substantial lens masses. Methods . In each event, we constrained the FS effect, and therefore established lower limits for the angular Einstein radius and lens mass. Additionally, we used the DarkLensCode software to obtain the mass, distance, and brightness distribution for the lens based on the Galactic model. Results . Our analysis established lower mass limits of ∼0.7 M⊙ for one lens and ∼0.3 − 0.5 M⊙ for two others. A DarkLensCode analysis supports these findings, estimating lens masses in the range of ∼0.42 − 1.70 M⊙ and dark lens probabilities exceeding 80%. These results strongly indicate that the lenses are stellar remnants, such as white dwarfs or neutron stars. Conclusions . While further investigations are required to confirm the nature of these lenses, we demonstrate a straightforward yet effective approach to identifying stellar remnant candidates.Peer reviewe
Social learning and expectational stability
No full textStability features of social learning (SL) dynamics are examined. We show SL can be formulated as a stochastic recursive algorithm, making it possible to analyze asymptotics using the familiar differential-equation approach. For a simple univariate model, this approach reduces to the E-stability principle, though in prominent instability cases divergence is exceedingly slow compared to adaptive learning (AL). We locate differing fitness criteria as the source of the slower evolution rates of SL compared to AL. Modifed AL and SL learning dynamics models are developed and used to illustrate the different implications of policy change in a standard New Keynesian model. We anticipate that the central question going forward will be how best to combine the two approaches when modeling adaptation to structural change.Peer reviewe
Towards TB elimination in Malawi : a 5-year analysis of key indicators for TB control using surveillance data
No full textFunding: This work was supported by The Global Fund through the Partnership to Enhance Technical Support for Analytical Capacity and Data Use in East and Southern Africa (PERSUADE) project (Global Fund Grant Number 2022-000076) and the Establishment and operationalization of regional community of practice for peer learning and knowledge sharing in integrated digital health analytics and data use (Global Fund Grant Number 2025-003179).Background: Malawi's TB Control Programme emphasises data-driven approaches for monitoring TB control efforts, but programmatic indicators have never been systematically evaluated. This study evaluates the performance of Malawi's TB Control Programme, providing insights into national trends, geographical distributions, and programmatic gaps in TB care. Methods: Aggregate TB data collected through Malawi's District Health Information System from 2018 to 2022 were analysed cross-sectionally. We analysed trends in TB incidence and case notification rates (CNRs), calculated performance indicators, and assessed district-level variations using time-series plots and statistical comparisons. Population estimates were derived from the 2018 census and adjusted for annual growth. Findings: Malawi reported 18,025 new persons with TB in 2022. From 2005 to 2018, TB incidence and CNRs declined by 68.6% and 54.5%, respectively. The highest CNRs were recorded among men aged 35-64 years. Treatment success rates improved overall, reaching 89.2% in 2022, though disparities persisted for HIV-positive patients and those treated at tertiary facilities. Conclusion: Challenges remain in Malawi's TB control efforts, particularly in addressing case detection gaps in high-burden districts and improving outcomes for vulnerable populations. Strengthening active case finding, enhancing diagnostic capacity, and addressing socio-economic determinants of health are essential for sustaining progress and achieving END-TB Strategy goals.Peer reviewe
Male mating behaviour is shaped by previous experience of both conspecific and heterospecific females in the seed bug Lygaeus simulans
No full textFunding: This work was supported by the University of St Andrews.Mating decisions are often context-dependent. For example, choosy individuals may benefit from relaxing mate preferences if conspecific mates are scarce. However, prior experience of heterospecifics can also alter mating decisions, and this can influence the strength of species discrimination and/or sexual selection. Here, we investigate the effect of previous mating opportunities on the subsequent mating decisions of male Lygaeus simulans seed bugs, a species known both to experience reproductive interference (reproductive interactions with heterospecifics that are costly) and also male mate choice for larger females. We used a nested, hierarchical design whereby focal males were: (1) paired with a conspecific female or remained unpaired on day 1; (2) paired with a conspecific female, a heterospecific female, or were unpaired on day 6; (3) paired with a conspecific female or a heterospecific female on day 8. The sister species L. equestris provided the heterospecific partners. We found that males were less likely to mate with heterospecific L. equestris females if they had previously encountered a heterospecific, but only if copulation had not occurred during that encounter. Additionally, the willingness of males to copulate with conspecifics increased when males had prior conspecific experience, and decreased with prior heterospecific experience, suggesting that male pre-copulatory mating decisions are plastic and can be influenced by experience of both con- and heterospecifics.Peer reviewe
Step 1: the Scottish Trauma & Orthopaedics Equality Project : demographics and working patterns of a national workforce
No full textAims: Trauma & Orthopaedic (T&O) surgery has come under scrutiny for lagging behind other medical specialties in promoting gender and cultural equity and diversity within their workforce. The proportions of female, ethnic minority, and sexual and gender minority individuals within orthopaedic membership bodies are disproportionate to the populations they serve. The aim of this study is to report the findings of a national workforce survey of demographics and working patterns within T&O in Scotland. Methods: A questionnaire devised by a working group was delivered by the Client Analyst and Relationship Development (CARD) group. Utilizing a secure third party ensured anonymity for all respondents. Data were recorded and analyzed by the CARD group. Results: A total of 353 responses were recorded, representing 71% of the known workforce. Overall, 261 respondents (74%) identified as male, 85 (24%) female, and seven (2%) preferred not to say. For specialist trainee (ST)3 to ST6, 148 (42%) were female, and for ST7 to ST8, 131 (37%) were female. In total, 226 of all respondents (64%) were white-British, 35 (10%) were white-European, and 92 (26%) were of an ethnic minority background. A total of 321 of respondents (91%) identified as heterosexual, 14 (4%) preferred not to say, and 18 (5%) identified as LGBTQ+ or preferred to self-describe. Conclusion: This is the largest national workforce survey in contemporary surgical literature. The findings demonstrate a greater proportion of female surgeons overall compared to other studies in T&O. This proportion of females was highest among more junior trainees. The Scottish T&O workforce is more ethnically diverse than the demographics of the population it serves. This study suggests that T&O in Scotland is an evolving speciality in terms of equality and diversity, and is making positive progress.Peer reviewe
Insulin levels early in perimenopause inform vasomotor symptom incidence across the menopausal transition
No full textTempleman Lab research is supported by funding from the Canadian Institutes of Health Research (PJT—183618). N.M.T. is a Tier 2 Canada Research Chair in Metabolic Determinants of Reproduction and Aging, and a Michael Smith Health Research BC Scholar. This study uses publicly available data from SWAN, which has had grant support through the National Institutes of Health (NIH), the Department of Health and Human Services, the National Institute on Aging, the National Institute of Nursing Research, and the NIH Office of Research on Women’s Health.Context: Metabolic health impacts the menopausal transition. Metabolic characteristics like body mass index (BMI) affect vasomotor syndrome incidence, but the role of elevated insulin, an early marker of metabolic dysfunction, remains understudied. Objective: To determine whether midlife insulin levels are associated with vasomotor symptom incidence or reproductive hormone trajectories. Methods: Longitudinal analyses of community-based data from the Study of Women's Health Across the Nation (SWAN) were conducted. We analyzed the 704 SWAN participants (of 3302) without oophorectomy or hysterectomy who had metabolic data for age 47 and did not take insulin/medications for hyperglycemia. Mean fasting insulin at 47 was 10.117 µIU/mL (SD = 6.711), with 27.0 kg/m2 BMI (SD = 6.6); mean age of final menstrual period for these participants was 51.0 years (SD = 2.3). Main outcome measures included vasomotor symptom timings and durations, and trajectories of estradiol, follicle-stimulating hormone (FSH), and testosterone across the menopausal transition. Results: Higher insulin at 47 predicted younger onsets of hot flashes and night sweats, longer durations of hot flashes and cold sweats, and greater testosterone rise. BMI associations with vasomotor symptoms paralleled those of insulin, but BMI appeared more closely linked to slower estradiol decline and blunted FSH rise. In Cox proportional hazards models, elevated age-47 insulin was associated with increased likelihood of hot flashes; this remained significant with BMI and glucose as covariates. Conclusions: Perimenopausal fasting insulin and BMI show complementary but distinct associations with menopausal changes. Elevated insulin predicts earlier and prolonged vasomotor symptoms, and is associated with higher testosterone.Peer reviewe
A laboratory-focussed desk review of health systems in Uganda, Kenya, and the UK to respond to current and future pandemics
No full textFunding: We acknowledge funding from the Scottish Funding Council/Global Challenges Research Fund grant (SM-DO-XFC119) and the School of Medicine University of St Andrews that funded WM’s PhD project.Background Laboratory systems play a crucial role in managing diseases effectively, and the COVID-19 pandemic serves as a prime example. The pandemic underscored the need to make laboratory health systems more resilient and robust to respond to future pandemics. Methods We conducted a desk review guided by the six World Health Organization health system building blocks (health service delivery, health financing, medical products, vaccines, and technologies, human resources for health, governance, and health information systems). Results The three countries’ strengths include health information systems, well-established reference laboratories, mobile and community-level testing, a vibrant private laboratory sector in Uganda and Kenya, and a growing private sector in the UK. In Uganda and Kenya, there are laboratory connectivity solutions for molecular diagnostics, multi-disease testing platforms and specimen referral systems, while in the UK, there are hub-and-spoke networks. Weaknesses in Uganda and Kenya include vertical laboratory systems strengthening, ill-equipped laboratories, constrained and inequitable distribution of laboratory human resources, and limited data use. In the UK, there is chronic underfunding and undervaluing of disciplines supporting infection testing, microbiology and virology. Conclusions The growing contribution of the private sector in the three countries and the deployment of multi-disease testing platforms should be supported, given the advantage of shared financial costs in the face of chronic underfunding for laboratory systems.Peer reviewe
Increasing confidence in dependently typed programs
No full textThere exist numerous methods for testing and verifying software, including property based testing, automatic code generation, model checking, and proof assistants. Although these tools help ensure that software behaves according to its specification, they are typically deployed in isolation rather than as reinforcements for one another. As software complexity grows, so does the complexity of modelling and checking the system. While rigorous approaches such as model checking and formal proofs provide strong correctness guarantees, these have difficulty scaling and often require reimplementing the code in a separate verification language. This risks the semantics being lost in translation, as there is no guarantee that the verified model behaves the same as the deployed code. Programming languages with dependent types – such as Idris2 – present novel ways to enforce correctness through dependently typed terms. However, the complexity of the dependent types also grows with the complexity of the system. This raises the question: "How does one know that the typed model used for checking matches the specification?" Since dependent types are effectively type-level programs, how might one try to ensure that they accurately model the problem and do not themselves contain errors?
This thesis explores several approaches to this problem. It presents a tool for generating types and code from diagrams, leveraging human strengths in visual reasoning. Additionally, a type-level property based testing framework is presented, allowing dependently typed stateful models to be tested. Both approaches are evaluated over stateful systems of increasing complexity, with even small systems giving rise to subtle bugs in a dependently typed model. These results demonstrate the value of the tools presented, which combine multiple degrees of verification into a single system and reduce the expertise required to increase the confidence in dependently typed programs while strengthening the relation between the checked model and the implementation."This work was supported by a Doctoral Training Grant from the School of Computer Science at the University of St Andrews, awarded in 2020 by the Head of School at the time: Professor Simon Dobson. I am forever grateful.
Parts of the work were also supported by EPSRC grant EP/T007265/1."--Fundin
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