179566 research outputs found
Sort by
The situated and everyday cultivation of transcultural capital in educational and home settings for migrant youth in Scotland
Get PDFScholars have identified that many young migrants employ transcultural capital to navigate difference in everyday life. In some cases, this enables migrants to resist social marginalisation, articulate empathy and challenge social hierarchies. This paper focuses on the significance and potential of the school, family and neighbourhood environments in the everyday cultivation of transcultural capital. To do this, we highlight the narratives of young migrants (age 16–18) in their final years of compulsory education, derived from a larger mixed-methods study on educational transitions in Scotland. This paper argues that (1) there is considerable variability between young migrants in the identification, development and mobilisation of transcultural capital and such capital is not to be assumed for migrant young people; (2) the ability to realise transcultural capital as an asset is highly situated in everyday contexts. This paper concludes that in order for transcultural capital to be mobilised, institutional contexts including schools need to have greater awareness of the processes through which transcultural capital can be nurtured for young migrants and a more intentional approach to fostering it
Identifying sex‐ and gender‐specific endocrinological, lifestyle, psychosocial, and socio‐cultural targets for Alzheimer's disease prevention in Africans: The Female Brain Health and Endocrine Research in Africa (FemBER‐Africa) project
Get PDFKinetics and Mechanism of Enantioselective Cu-Catalyzed Alcohol Silylation
Get PDFThe enantioselective Cu-catalyzed dehydrogenative Si–O coupling of secondary benzylic alcohols with (nBu)3SiH was investigated using a combination of in situ 1H/19F NMR spectroscopic reaction monitoring, isotopic labeling, kinetic modeling, and computational studies. Macrokinetic behavior is governed by substrate-inhibited L*CuOR·ROH resting states: rates rise with conversion when [(nBu)3SiH] > [ROH] and fall when [(nBu)3SiH] < [ROH]. Alcohols bearing electron-withdrawing substituents are stronger inhibitors and show overall lower macrokinetic reactivity, but react faster than alcohols with electron-donating substituents in intermolecular competitions, indicating that inhibition is more substituent-sensitive than the product-committing step. Divergence between intrinsic enantioselectivity and observed macrokinetic rates of enantiomers in isolation results from enantiomer-dependent inhibition, and a product-committing σ-bond-metathesis step is consistent with measured Eyring activation parameters and a Si–H/Si–D KIE ≤ 1.3. Eyring and Hammett analyses, as well as DFT calculations, support an H-bonding inhibition mode for the L*CuOR·ROH resting state. Stoichiometric styrene as an additive suppresses H2 generation and mitigates catalyst deactivation, increasing process safety and efficiency. Dynamic kinetic resolution, enabled by addition of a ruthenium racemization cocatalyst, results in reaction rates comparable to those of the faster enantiomer while improving overall efficiency
Downdraft Devices for Negative Emissions—Quantification Study and Environmental Implication
No full textMethane (CH4) is a potent greenhouse gas with a global warming potential far exceeding that of CO2 over short time horizons. Its removal from the atmosphere remains challenging due to its low ambient concentration and chemical stability. This study explores downdraft energy towers (DETs) as an innovative CH4 mitigation technology that enhances the dominant hydroxyl radical (·OH) sink via water vapor release. A coupled modeling framework integrating computational fluid dynamics (CFD) and a simplified atmospheric chemistry model was developed to quantify the influence of operational parameters, environmental conditions, and tower scale. The CFD simulations evaluated internal flow dynamics and water vapor output, whereas the atmospheric model estimated ·OH production and CH4 oxidation potential. Results indicate that higher water injection rates, elevated ambient temperatures, and lower relative humidity markedly increase downdraft strength, vapor emissions, and ·OH formation. Scaling analysis showed that an 800 DET could remove up to 141.17 t CH4 per year, with the highest efficiency in hot, dry climates. These findings highlight DETs as a promising complementary option for greenhouse gas mitigation and provide guidance for optimizing their design and deployment in climate engineering strategies.</p
Antenatal Corticosteroids and Infectious Diseases Throughout Childhood
No full textIMPORTANCE: International guidelines recommend the use of antenatal corticosteroids (ACS) in pregnancies at risk of imminent preterm birth before 34 weeks' gestation. However, whether ACS leads to long-term risk of infection from childhood to adulthood is unknown.OBJECTIVE: To determine whether preterm (<37 weeks' gestation) and full-term (37-41 weeks' gestation) children exposed to ACS are more susceptible to respiratory and nonrespiratory infections compared with ACS-unexposed children throughout childhood and adolescence.DESIGN, SETTING, AND PARTICIPANTS: This population-based cohort study used data from the multicenter Consortium for the Study of Pregnancy Treatments (Co-OPT) study, including data from nationwide registries for mothers and their children in Finland and Scotland. Singleton children born from 1997 to 2018 and 2006 to 2018 in Scotland and Finland, respectively, were followed up until 2018, death, or first infection. Data were analyzed between June 2022 and October 2023.EXPOSURES: Maternal ACS treatment.MAIN OUTCOMES AND MEASURES: Primary and secondary outcomes were the first diagnosis of respiratory or nonrespiratory infection after birth-related hospital discharge. Outcomes were stratified by gestational age at birth.RESULTS: Among 1 548 538 included mother-child pairs (mean [SD] maternal age, 29.4 [5.7] years; mean [SD] gestational age at birth, 39.2 [1.7] weeks; 759 082 [49.0%] female neonates), 49 263 children (3.2%) were ACS-exposed, of whom 34 806 (70.7%) were preterm and 14 457 (29.3%) were full term at birth. ACS-exposed children had more respiratory and nonrespiratory infections than nonexposed children (incidence rate, 65.2 vs 39.8 and 30.0 vs 17.9 per 1000 person-years, respectively). Compared with nonexposed children, higher risks for respiratory and nonrespiratory infections were found among ACS-exposed children born at 34 weeks 0 days to 36 weeks 6 days' gestation (adjusted hazard ratios [HRs], 1.10 [95% CI, 1.06-1.14] and 1.19 [95% CI, 1.15-1.24]), 37 0/7 to 38 6/7 weeks' gestation (adjusted HRs, 1.27 [95% CI, 1.21-1.32] and 1.17 [95% CI, 1.11-1.23]), and 39 weeks 0 days to 41 weeks 6 days' gestation (adjusted HRs, 1.23 [95% CI, 1.16-1.30] and 1.31 [95% CI, 1.22-1.40]). However, ACS-exposed children born at 28 weeks 0 days to 31 weeks 6 days' gestation and 32 weeks 0 days to 33 weeks 6 days' gestation showed no association between ACS exposure and respiratory and nonrespiratory infections.CONCLUSION AND RELEVANCE: In this cohort study, exposure to ACS was associated with increased risks of infections in full-term children until age 21 years. In preterm children born before 34 weeks' gestation, no association between ACS and infections was found. To minimize the adverse effects of ACS treatment, more stringent criteria for ACS administration and better prediction tools for preterm birth are required.</p
BIA Transmission in Rate Splitting-based Optical Wireless Networks
No full textOptical wireless communication (OWC) has recently received massive interest as a new technology that can support the enormous data traffic increasing on daily basis. In particular, laser-based OWC networks can provide terabits per second (Tbps) aggregate data rates. However, the emerging OWC networks require a high number of optical access points (APs), each AP corresponding to an optical cell, to provide uniform coverage for multiple users. Therefore, inter-cell interference (ICI) and multi-user interference (MUI) are crucial issues that must be managed efficiently to provide high spectral efficiency. In radio frequency (RF) networks, rate splitting (RS) is proposed as a transmission scheme to serve multiple users simultaneously following a certain strategy. It was shown that RS provides high data rates compared to orthogonal and non-orthogonal interference management schemes. Considering the high density of OWC networks, the application of RS within each optical cell might not be practical due to severe ICI. In this paper, a novel strategy is derived, referred to as blind interference alignment-rate splitting (BIA-RS), to fully coordinate the transmission among the optical APs, while determining the precoding matrices of multiple groups of users formed beforehand. Therefore, RS can be implemented within each group to manage MUI. The proposed BIA-RS scheme requires two layers of power allocation to achieve high performance. Given that, a max-min fractional optimization problem is formulated to optimally distribute the power budget among the groups and the messages intended to the users of each group. Finally, a power allocation algorithm is designed with multiple Lagrangian multipliers to provide practical and sub-optimal solutions. The results show the high performance of the proposed scheme compared to other counterpart schemes.</p
Loss of tropical moist broadleaf forest has turned Africa’s forests from a carbon sink into a source
No full textAfrica’s forests and woody savannas have historically acted as a carbon sink, removing atmospheric carbon and storing it as biomass. However, our novel analysis reveals a critical transition from a carbon sink to a carbon source between 2010 and 2017. Using new high-resolution satellite-derived biomass maps, validated with field plots and machine learning techniques, we quantified the aboveground biomass stocks across African biomes over a decade. Between 2007 and 2010, the continent gained 439 ± 66 Tg yr⁻1 of aboveground biomass, but from 2010 to 2015 biomass declined by − 132 ± 20 Tg yr-1 and from 2015 to 2017 this decline continued with a loss of − 41 ± 6 Tg yr-1, primarily driven by deforestation in tropical moist broadleaf forests. Gains in savanna biomass partially offset these losses, likely due to shrub encroachment. Our findings underline the urgent need for implementing policies to halt global deforestation as required by the Glasgow Leaders Declaration to close the global emissions gap. The current ongoing revisions of Nationally Determined Contributions to the Paris Agreement need to be even more ambitious to compensate for the ongoing loss of natural carbon sinks
Avian-origin influenza A viruses tolerate elevated pyrexic temperatures in mammals
No full textHost body temperature can define a virus's replicative profile-influenza A viruses (IAVs) adapted to 40° to 42°C in birds are less temperature sensitive in vitro compared with human isolates adapted to 33° to 37°C. In this work, we show that avian-origin PB1 polymerase subunits enable IAV replication at elevated temperatures, including avian-origin PB1s from the 1918, 1957, and 1968 pandemic viruses. Using a model system to ensure biosafety, we show that a small increase in body temperature protects against severe disease in mice and that this protection is overcome by a febrile temperature-resistant PB1. These findings indicate that although elevated temperature itself can be a potent antiviral defense, it may not be effective against all influenza strains. These data inform both the clinical use of antipyretics and IAV surveillance efforts.</p
Accessible, Realistic Genome Simulation with Selection Using stdpopsim
No full textSelection is a fundamental evolutionary force that shapes patterns of genetic variation across species. However, simulations incorporating realistic selection along heterogeneous genomes in complex demographic histories are challenging, limiting our ability to benchmark statistical methods aimed at detecting selection and to explore theoretical predictions. stdpopsim is a community-maintained simulation library that already provides an extensive catalog of species-specific population genetic models. Here, we present a major extension to the stdpopsim framework that enables simulation of various modes of selection, including background selection, selective sweeps, and arbitrary distributions of fitness effects (DFE) acting on annotated subsets of the genome (for instance, exons). This extension maintains stdpopsim's core principles of reproducibility and accessibility while adding support for species-specific genomic annotations and published DFE estimates. We demonstrate the utility of this framework by comparing methods for demographic inference, DFE estimation, and selective sweep detection across several species and scenarios. Our results demonstrate the robustness of demographic inference methods to selection on linked sites, reveal the sensitivity of DFE-inference methods to model assumptions, and show how genomic features, like recombination rate and functional sequence density, influence power to detect selective sweeps. This extension to stdpopsim provides a powerful new resource for the population genetics community to explore the interplay between selection and other evolutionary forces in a reproducible, user-friendly framework.</p
Access Repository Dashboard
Do you manage Edinburgh Research Explorer? Access insider analytics, issue reports and manage access to outputs from your repository in the CORE Repository Dashboard!