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Long-term fertility trends by birth order in Britain : comparison between England & Wales and Scotland
Get PDFFunding: This research was supported by the Economic and Social Research Council (ESRC), grant number ES/S009477/1 (Understanding Recent Fertility Trends in the UK and Improving Methodologies for Fertility Forecasting).This study uses census-linked administrative data to investigate childbearing trends by birth order in Britain over three decades. This is the first study to investigate longer-term changes in fertility dynamics in Britain by birth order and to compare parity-specific fertility by country. First-birth rates declined in the 1990s, slightly increased in the first decade of this century, and decreased thereafter, with changes in timing of parenthood responsible for these changes. Second- and third-birth rates declined in the 1990s but remained relatively stable in the early twenty-first century. Birth intervals remained unchanged, meaning that changes in quantum are responsible for trends in higher-order birth rates. Time trends are similar in England & Wales and Scotland but with significantly lower second- and third-birth rates in Scotland. Changes in population composition by education and ethnicity explain little of the aggregate fertility trends or between-country differences. Both countries have seen rapid declines in first-birth rates, especially among low-educated women.Peer reviewe
On the relation between magnetic field strength and gas density in the interstellar medium : a multiscale analysis
Get PDFFunding: DJW acknowledges support from the Programa de Becas Posdoctorales of the Dirección General de Asuntos del Personal Académico of the Universidad Nacional Autónoma de México (DGAPA,UNAM,Mexico). SS acknowledges support from UNAM-PAPIIT Program IA10484. REP is supported by a Discovery Grant from NSERC, Canada. He is also grateful for support of his sabbatical leave in Heidelberg (2022/23), by the Institute for Theoretical Astrophysics of the University of Heidelberg (ITA) and the Max Planck Institute for Astronomy, where this work was started. RJS gratefully acknowledges an STFC Ernest Rutherford fellowship (grant ST/N00485X/1). M-MML acknowledges direct support from US National Science Foundation grants AST18-15461 and AST23-07950, as well as support from grant PHY23-09135 to the Kavli Institute for Theoretical Physics. LSV was supported by the Science Pathways Scholars Program of Barnard College. RP acknowledges funding support from Ontario Graduate Scholarships and the Queen Elizabeth II Graduate Scholarship in Science & Technology. AP acknowledges financial support from the grant UNAMPAPIIT IG100223, the Sistema Nacional de Investigadores of CONAHCyT, and from the CONAHCyT project number 86372 of the ‘Ciencia de Frontera 2019’ programme, entitled ‘Citlalcóatl: A multiscale study at the new frontier of the formation and early evolution of stars and planetary systems’, México. DJW, PG, NB, UL, PH, RSK, and JDS acknowledge funding from the European Research Council via the ERC Synergy Grant ‘ECOGAL’ (project ID 855130). RSK is grateful to the German Excellence Strategy for funding via the Heidelberg Cluster of Excellence ‘STRUCTURES’ (EXC 2181–390900948), and to BMWK for support in project ‘MAINN’ (funding ID 50OO2206). The team in Heidelberg acknowledges computing resources provided by The Län and DFG through grants INST 35/1134-1 FUGG and 35/1597-1 FUGG, data storage at SDS@hd funded through grants INST 35/1314-1 FUGG and INST 35/1503-1 FUGG, as well as computing resources provided by the Leibniz Rechenzentrum via grants pr32lo, pr73fi and GCS large-scale project 10391.The relationship between magnetic field strength B and gas density n in the interstellar medium is of fundamental importance. We present and compare Bayesian analyses of the B–n relation for two comprehensive observational data sets: a Zeeman data set and 700 observations using the Davis–Chandrasekhar–Fermi (DCF) method. Using a hierarchical Bayesian analysis we present a general, multiscale broken power-law relation, B = B0(n/n0)α, with α = α1 for n n0, and with B0 the field strength at n0. For the Zeeman data, we find: α1 = 0.15+0.06−0.09 for diffuse gas and α2 = 0.53+0.09−0.07 for dense gas with n0 = 0.40+1.30−0.30 × 104 cm−3. For the DCF data, we find: α1 = 0.26+0.01−0.01 and α2 = 0.77+0.14−0.15, with n0 = 14.00+10.00−7.00 × 104 cm−3, where the uncertainties give 68 per cent credible intervals. We perform a similar analysis on nineteen numerical magnetohydrodynamic simulations covering a wide range of physical conditions from protostellar discsto dwarf and Milky Way-like galaxies, computed with the AREPO, FLASH, PENCIL, and RAMSES codes. The resulting exponents depend on several physical factors such as dynamo effects and their time-scales, turbulence, and initial seed field strength. We find that the dwarf and Milky Way-like galaxy simulations produce results closest to the observations.Peer reviewe
G-band FMCW Doppler radar for close-range environmental sensing
Get PDFFunding: This work was supported by the U.K. Engineering and Physical Sciences Research Council (EPSRC) under Grant EP/S032851/1. Aleksanteri B. Vattulainen’s Ph.D. was funded by the EPSRC.Radar systems operating within the 220 GHz atmospheric transmission window are comparatively rare despite the benefits they offer in high angular, range, and Doppler resolutions. Given the growing availability of solid-state signal generation components designed for this frequency range, interest in the sensing potential of this region is increasing. This paper presents the development and characterization of ‘Theseus’, a 207 GHz FMCW Doppler radar designed for sea clutter and marine target characterization but also capable of a large variety of other close-range environmental sensing uses. The radar carrier frequency is tunable between 200-208 GHz with a maximum chirp bandwidth of 2 GHz resulting in a range resolution of 7.5 cm, and a chirp repetition interval (CRI) of 67.59 μs giving a maximum unambiguous velocity of ±5.36 ms−1 . Several measurement application examples are presented, showcasing a wealth of micro-Doppler and micro-range information gathered from a variety of targets and clutter including sea clutter, humans swimming and running, UAV flight, a plan position indicator (PPI) scan of a terrestrial environment, and rain clutter. Data in this frequency band are very rare in the open literature, and thus the high range and Doppler resolution measurement capabilities of this radar present an opportunity to expand the knowledge in this area.Peer reviewe
Reflections on confronting a capacity challenge with an AI-powered patient simulator (SimPatient)
Get PDFFunding: ComSIM: Community Orientated Simulation, University of St Andrews.Peer reviewe
Coevolution of life and environment during the Ediacaran-Cambrian transition : clues from litho-, bio-, and chemostratigraphy of the Corumbá Group, Brazil
Get PDFFunding: The authors acknowledge the São Paulo Research Foundation (FAPESP), through which we received funding under projects 2016/06114-6, 2020/16140-0, 2020/03347-5, 2022/04186-0, and 2021/02628-3, and the Brazilian National Council for Scientific and Technological Development (CNPq) through which we received funding under project 140745/2021-1. RIF and PCB are fellows of CNPq. GMPS currently holds a Deutsche Forschungsgemeinschaft (DFG) scholarship (grant #497339722). FB acknowledges support from UKRI Project EP/Y008790/1.This study presents new litho-, bio-, and chemostratigraphic data of the late Ediacaran Corumbá Group (Brazil) obtained from two drill cores that were collected as part of the GRIND-ECT project (Geological Research through Integrated Neoproterozoic Drilling – Ediacaran-Cambrian Transition). This is the first study encompassing, continuously, the Bocaina (ca. 570–555 Ma) and Tamengo (ca. 550–540 Ma) formations, which are key carbonate units from the upper Corumbá Group and optimal archives for investigating the ECT in Western Gondwana. Sequence stratigraphic analysis reveals two third-order transgressive–regressive cycles. A sequence boundary at the Bocaina-Tamengo Limit (BTL) formed during a major, potentially glacio-eustatic, regression, after which the morphology of the carbonate platform changed from a rimmed/open shelf to a distally-steepened ramp. Biostratigraphic analysis constrains the lowest regional occurrence of Cloudina shortly above the BTL. Four species of acritarchs from the genus Leiosphaeridea and Germinosphaera are documented in the Tamengo Formation, revealing an association with the Late Ediacaran Leiosphere Palynoflora. Cloudina and Leiosphaeridea show biostratigraphic trends linked to third-order cycles, being more abundant during shallower intervals. The δ13Ccarb curve in the Bocaina Formation exhibits a relatively stable trend around +2 ‰, followed by a minor negative excursion (n1) down to −1.7 ‰ at the BTL, which is also present in other sections on the Corumbá platform. Above n1, the Tamengo Formation exhibits a positive excursion reaching values of +6 ‰. Confidence in precise correlation between the global carbon isotope curve and the Corumbá Group curve is somewhat hampered, given the uncertain age of the lowermost Bocaina Formation. It is possible that n1 is temporally equivalent to the globally documented negative excursion at 550 Ma, suggesting that these excursions, in part, result from diagenetic alteration or local effects that were exacerbated during a major glacio-eustatic regression. Despite having values consistent with the Late Ediacaran Positive carbon Isotope Plateau, the Tamengo Formation lacks negative excursions that may exist in the global curve, such as A0, which may cast doubt on the global nature of this event. The links between sequence-, bio-, and chemostratigraphy presented herein indicate an intricate coevolution of life and environment during the ECT.Peer reviewe
Post-pleistocene colonisation rather than the contemporary environment has most influenced the current population structure of Scottish Atlantic salmon (Salmo salar)
Get PDFGenetic structuring in populations is the result of both historical and contemporary environmental factors driving genetic drift, natural selection and gene flow, as well as purely genetic factors, such as mutation and recombination. In Atlantic salmon (Salmo salar), re-colonisation of rivers after the last Ice Age was shown to be an important factor in shaping contemporary population structure, though the observed structure was more complex than was predicted through founder effects. Thus, other, perhaps more contemporary factors may also play a role. Here, we investigated the influence of the time since deglaciation, distance to the sea, population connectivity, temperature, water quality, waterbody modifications, and environmental protections on spatial structuring of genetic diversity, based on microsatellite data (33 loci) collected from 48 Scottish S. salar populations. The results confirmed that recently deglaciated areas are less genetically diverse and more differentiated. Modified waterbodies also exhibit less genetic diversity and greater differentiation, although this effect differs between rivers draining on the east and west coasts of Scotland. Distance to the sea also had a non-negligible effect, while the other considered factors did not have a significant effect.Peer reviewe
Near-infrared transmission spectroscopy of HAT-P-18 b with NIRISS : disentangling planetary and stellar features in the era of JWST
No full textFunding: This project is undertaken with the financial support of the Canadian Space Agency. MFT acknowledges financial support from the Fonds de Recherche du Québec – Nature et technologies (FRQNT) and funding from the Trottier Family Foundation in their support of iREx. RJM acknowledges support for this work provided by NASA through the NASA Hubble Fellowship grant number HST-HF2-51513.001, awarded by the Space Telescope Science Institute (STScI), which is operated by the Association of Universities for Research in Astronomy, Inc., for NASA, under contract NAS5-26555. MR acknowledges financial support from the Natural Sciences and Engineering Research Council of Canada (NSERC) as well as from FRQNT and iREx. CP acknowledges support from FRQNT and TEPS Ph.D. scholarships and the NSERC Vanier scholarship. KM acknowledges financial support from the FRQNT. OL acknowledges financial support from FRQNT and iREx. DJ is supported by NRC Canada and by an NSERC Discovery Grant. JDT was supported for this work by NASA through the NASA Hubble Fellowship grant number HST-HF2-51495.001-A awarded by the STScI, which is operated by the Association of Universities for Research in Astronomy, Incorporated, under NASA contract number NAS5-26555.The JWST Early Release Observations (ERO) included a NIRISS/SOSS (0.6–2.8 μm) transit of the ∼ 850 K Saturn-mass exoplanet HAT-P-18 b. Initial analysis of these data reported detections of water, escaping helium and haze. However, active K dwarfs like HAT-P-18 possess surface heterogeneities – star-spots and faculae – that can complicate the interpretation of transmission spectra, and indeed, a spot-crossing event is present in HAT-P-18 b’s NIRISS/SOSS light curves. Here, we present an extensive reanalysis and interpretation of the JWST ERO transmission spectrum of HAT-P-18 b, as well as HST/WFC3 and Spitzer/IRAC transit observations. We detect H2O (12.5σ), CO2 (7.3σ), a cloud deck (7.4σ), and unocculted star-spots (5.8σ), alongside hints of Na (2.7σ). We do not detect the previously reported CH4 (log CH4 < −6 to 2σ). We obtain excellent agreement between three independent retrieval codes, which find a sub-solar H2O abundance (log H2O ≈ −4.4 ± 0.3). However, the inferred CO2 abundance (log CO2 ≈ −4.8 ± 0.4) is significantly super-solar and requires further investigation into its origin. We also introduce new stellar heterogeneity considerations by fitting for the active regions’ surface gravities – a proxy for the effects of magnetic pressure. Finally, we compare our JWST inferences to those from HST/WFC3 and Spitzer/IRAC. Our results highlight the exceptional promise of simultaneous planetary atmosphere and stellar heterogeneity constraints in the era of JWST and demonstrate that JWST transmission spectra may warrant more complex treatments of the transit light source effect.Peer reviewe
A widely-occurring family of pore-forming effectors broadens the impact of the Serratia Type VI secretion system
Get PDFFunding: This work was supported by Wellcome (grant numbers 104556/Z/14/Z, Senior Research Fellowship S.J.C.; and 220321/Z/20/Z, Senior Research Fellowship Renewal S.J.C.), UKRI Medical Research Council (grant numbers MR/K000111X/1, New Investigator Research Grant, S.J.C.; and MR/T041811/1, Future Leaders Fellowship, M.B.), UKRI Biotechnology and Biological Sciences Research Council (grant numbers BB/M010996/1 and BB/T00875X/1, EASTBio PhD studentships K.M. and A.T.G.), Academy of Medical Sciences (grant number SBF005/1096, Springboard Grant, M.B.; the Springboard scheme is funded by Wellcome, the Department of Business, Energy, and Industrial Strategy UK, the British Heart Foundation, and Diabetes UK) and the British Heart Foundation (grant number FS/PhD/22/2932, non-clinical PhD studentship Q.W.H.).Delivery of antibacterial effector proteins into competitor cells using the Type VI secretion system (T6SS) is a widespread strategy for inter-bacterial competition. While many enzymatic T6SS effectors have been described, relatively few which form pores in target cell membranes have been reported. Here, we describe a widely-occurring family of T6SS-dependent pore-forming effectors, exemplified by Ssp4 of Serratia marcescens Db10. We show in vitro that Ssp4 forms regulated pores with high selectivity for cations, and use structural models and molecular dynamics simulations to predict how these pores conduct ions. Ssp4 has a broader phylogenetic distribution and is active against a wider range of bacterial species than Ssp6, the other pore-forming effector delivered by the same T6SS, with the two effectors displaying distinct ion selectivities and impacts on intoxicated cells. Finally, identification of Ssp4-resistant mutants revealed that a mucA mutant of Pseudomonas fluorescens is protected against T6SS attacks. We propose that deployment of two distinct T6SS-dependent pore-forming toxins is a common strategy to ensure effective de-energisation of closely- and distantly-related competitors.Peer reviewe
How do stratospheric perturbations influence North American weather regime predictions?
Get PDFFunding: S.H.L. was funded by the Natural Environment Research Council (NERC) via the SCENARIO Doctoral Training Partnership (NE/L002566/1) at the University of Reading. S.J.W was supported by the National Centre for Atmospheric Science, a NERC collaborative centre.Observational evidence shows changes to North American weather regime occurrence depending on the strength of the lower-stratospheric polar vortex. However, it is not yet clear how this occurs or to what extent an improved stratospheric forecast would change regime predictions. Here we analyze four North American regimes at 500 hPa, constructed in principal component (PC) space. We consider both the location of the regimes in PC space and the linear regression between each PC and the lower-stratospheric zonal-mean winds, yielding a theory of which regime transitions are likely to occur due to changes in the lower stratosphere. Using a set of OpenIFS simulations, we then test the effect of relaxing the polar stratosphere to ERA-Interim on subseasonal regime predictions. The model start dates are selected based on particularly poor subseasonal regime predictions in the European Centre for Medium-Range Weather Forecasts CY43R3 hindcasts. While the results show only a modest improvement to the number of accurate regime predictions, there is a substantial reduction in Euclidean distance error in PC space. The average movement of the forecasts within PC space is found to be consistent with expectation for moderate-to-large lower-stratospheric zonal wind perturbations. Overall, our results provide a framework for interpreting the stratospheric influence on North American regime behavior. The results can be applied to subseasonal forecasts to understand how stratospheric uncertainty may affect regime predictions, and to diagnose which regime forecast errors are likely to be related to stratospheric errors.Peer reviewe
Disease accumulation across birth cohorts in South Korea
Get PDFFunding: This work was supported by a St Andrews-Max Planck PhD Studentship in Population Health (to A.L.); the Academy of Medical Sciences, the Wellcome Trust, the Government Department of Business, Energy and Industrial Strategy, the British Heart Foundation Diabetes UK, and the Global Challenges Research Fund (Grant number SBF004\1093 to K.K.); the Economic and Social Research Council Centre for Population Change and the Economic and Social Research Council Connecting Generations research program (Grant numbers ES/K007394/1 and ES/W002116/1 to H.K.); and M.M. was supported by the Strategic Research Council (SRC), FLUX consortium, decision numbers 345130 and 345131; by the National Institute on Aging (R01AG075208); by grants to the Max Planck—University of Helsinki Center from the Max Planck Society (Decision number 5714240218), Jane and Aatos Erkko Foundation, Error! Hyperlink reference not valid. at the University of Helsinki, and Cities of Helsinki, Vantaa and Espoo; and the European Union (ERC Synergy, BIOSFER, 101071773). Views and opinions expressed are, however, those of the author only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them.Objectives This article estimates rates and age-trajectories of disease accumulation across South Korean birth cohorts and assesses whether observed cohort differences persist after accounting for early-life exposures and adult characteristics. Methods Data were from eight waves of the Korean Longitudinal Study of Aging (2006–2020) and included 8,202 participants aged 50 to 74 years. Birth cohorts were defined by historical periods: Japanese annexation (1932–1944), Korean liberation (1945–1949), Korean War (1950–1953), and Post-war (1954–1961). Poisson mixed-effects models were used to estimate disease accumulation using counts of self-reported chronic diseases. Models were built stepwise from a baseline model with cohort fixed effects. Subsequent models added a cohort/age interaction, early-life exposures (parental death and education), and adult characteristics (own education, residence, smoking, and obesity). Results The Post-war (1954–1961) cohort has lower rates of disease accumulation than the older cohorts, which do not differ substantially from each other. Controlling for early-life exposures slightly reduces cohort differences, but controlling for adult characteristics leads to a larger reduction, leaving only the Korean liberation (1945–1949) cohort significantly different from the Post-war (1954–1961) cohort (IRR: 1.17, 95% CI: 1.07–1.29). This suggests adult characteristics explain most of the observed differences between the Post-war (1954–1961) and older cohorts, except the Korean liberation (1945–1949) cohort, which remains uniquely different due to unobserved factors. Discussion These findings highlight how historical context and life course experiences are jointly associated with disease accumulation across cohorts. Adult characteristics play an important role, especially for older cohorts, and could be considered as important targets for disease prevention strategies.Peer reviewe
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