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Changes in functional area and land cover in hunting blocks in northern Tanzania
Get PDFTrophy hunting (TH) is a form of wildlife use in which individuals pay to hunt under regulated conditions and retain selected body parts as trophies. Tanzania permits TH in areas with different land-use designations, covering diverse habitats. However, human activities such as settlement, agriculture and livestock grazing can threaten habitats and wildlife populations, particularly as revenue from TH declines. Using satellite data from between 2013 and 2023, we quantified changes in functional area and land cover across 15 hunting blocks in northern Tanzania. Over this period, functional area in hunting blocks decreased by c. 22.4% in Game Controlled Areas (GCAs) and by c. 18.0% in Open Areas (OAs), attributed to human encroachment. Longido North GCA experienced the most substantial land-cover change, with a 76% increase in dense vegetation. An analysis comparing the 2013–2019 and 2019–2023 data revealed consistent shrinkages in grassland and mixed and dense vegetation within the Longido North GCA, Masai OA and Irkishbor OA hunting blocks. Although individual land-cover losses in the given periods remained below 50% (our threshold for major habitat loss), these cumulative changes reduce habitat suitability, posing risks to biodiversity and the sustainability of TH. This study reveals the extent of human pressures on hunting blocks and calls for integrated regional planning, active management and targeted conservation strategies
The genetic consequences of dispersal and immigration in a wild great tit population
Get PDFUnderstanding how dispersal impacts the genetic makeup of populations is essential for predicting their responses to environmental change. Gene flow—via within-population dispersal and external immigration—shapes population health and evolutionary potential by boosting genetic diversity, but it can also counteract local adaptation. We investigate these processes in a population of great tits (Parus major) in Wytham Woods, United Kingdom. This system represents a large, continuous population of a vagile, widely distributed species. Using a comprehensive social pedigree alongside two genomic datasets, one with 949 individuals genotyped at 600,000 SNPs and another with 2,644 individuals typed at 10,000 SNPs, we demonstrate spatial genetic structure largely driven by the spatial and temporal clustering of close kin. We quantify how temporally persistent this pattern is and find that relatedness declines with geographic distance in a consistent manner across years, without a consistent genetic basis, a pattern which is frequently renewed due to high population turnover. Immigrants make up a substantial portion of the breeding population, yet are often assumed to be genetically distinct, unrelated, and outbred—assumptions that can bias population inferences. We show that immigrants are indeed outbred, as are local birds; have fewer close relatives within the population, and are less likely to be related to their neighbours than locally born birds. Despite low FST and no clear genome-wide population structure, immigrants and locals can be distinguished above chance using a Random Forest classifier trained on SNP data. Our study highlights the complex interplay between dispersal, population turnover and spatial population structure, and suggests that great tits in Wytham Woods experience substantial gene flow within the population and from immigrants, maintaining high genetic diversity and reducing the possibility of local adaptation at this spatial scale
Progression independent of relapse activity and relapse-associated worsening in seronegative NMOSD: an international cohort study
Get PDFBackgroundPrevious studies have indicated that progression independent of relapse activity (PIRA) is uncommon in patients with aquaporin- 4 antibody-positive (AQP4-IgG) neuromyelitis optica spectrum disorder (NMOSD). However, the patterns of disability accumulation in seronegative NMOSD are unknown. This study aimed to evaluate the prevalence of PIRA and relapse-associated worsening (RAW) in seronegative NMOSD.MethodsWe conducted a retrospective, multicentre cohort study of seronegative NMOSD patients from the MSBase registry. Inclusion criteria required at least three recorded expanded disability status scale (EDSS) scores: baseline, progression, and 6 months confirmed disability progression (CDP). For those with 6-month CDP, the presence or absence of relapse between baseline and progression determined the classification as RAW or PIRA, respectively. Descriptive statistics were employed to present the data.ResultsThis study included 93 patients, with a median follow-up duration of 5.0 years (Q1 2.8, Q3 8.4). The cohort predominantly consisted of female patients (77.4%), with a median age of onset of 33.9 years (Q1 26.1, Q3 41.2). PIRA was observed in 1 case (1.1%), whilst RAW was documented in 7 cases (7.5%).ConclusionThis international cohort study confirms that CDP is uncommon in seronegative NMOSD. Given more than three quarters of CDP occur due to RAW, therapeutic strategies should focus primarily on preventing relapses
Ultrasound-Based Tomographic Imaging Reconstruction and Synthesis Methods: a Scoping Review
Get PDFUltrasound (US) imaging is valued for its safety, affordability, and accessibility, but its low spatial resolution and operator dependence limit its diagnostic capabilities. Tomographic imaging modalities like computed tomography (CT) and magnetic resonance imaging (MRI) offer high-resolution 3D visualization but are cost-prohibitive and complex. Ultrasound-based tomographic imaging aims to combine the advantages of both modalities, potentially democratizing access to advanced imaging. A scoping review was conducted following PRISMA-SR guidelines. Articles were identified through searches in PubMed MEDLINE, Embase, Scopus, and arXiv from inception to July 2025. Eligibility criteria included full-text original studies focused on ultrasound-based tomographic imaging generation or reconstruction methods. Out of 8256 identified articles, 86 met the inclusion criteria. Studies examined four imaging modalities: photoacoustic tomography (36%), ultrasound computed tomography (36%), 3D reconstruction (20%), and synthetic imaging (7%). Deep learning algorithms (67%) were the most common, followed by iterative reconstruction algorithms (9%), and other methods. The breast (17%), brain (16%), and blood vessels (14%) were the most studied anatomical regions. This review highlights advancements in ultrasound-based tomographic imaging, driven by deep learning innovations. Despite progress, the field is still in its infancy, and challenges remain in clinical adoption, particularly in standardization and validating performance. Future research should focus on improving algorithm efficiency, generalizability, and validation
Metal-centred states control carrier lifetimes in transition metal oxide photocatalysts
Get PDFEfficient sunlight-to-energy conversion requires materials that can generate long-lived charge carriers upon illumination. However, the targeted design of semiconductors possessing intrinsically long lifetimes remains a key challenge. Here using a series of transition metal oxides, we establish a link between carrier lifetime and electronic configuration in transition metal-based semiconductors. We identify a subpicosecond relaxation mechanism via metal-centred ligand field states that compromise quantum yields in open d-shell transition metal oxides (for example, Fe2O3, Co3O4, Cr2O3 and NiO), which is more reminiscent of molecular complexes than crystalline semiconductors. We found that materials with spin-forbidden ligand field transitions could partially mitigate this relaxation pathway, explaining why Fe2O3 achieves higher photoelectrochemical activity than other visible light-absorbing transition metal oxides. However, achieving high yields of long-lived charges requires transition metal oxides with d0 or d10 electronic configurations (for example, TiO2 and BiVO4), where ligand field states are absent. These trends translate to transition metal-containing semiconductors beyond oxides, enabling the design of photoabsorbers with better-controlled recombination channels in photovoltaics, photocatalysis and communication device
Patient characteristics associated with clinically coded long COVID: an OpenSAFELY study using electronic health records
Get PDFBackground Clinically coded long COVID cases in electronic health records are incomplete, despite reports of rising cases of long COVID. Aim To determine patient characteristics associated with clinically coded long COVID. Design & setting With the approval of NHS England, we conducted a cohort study using electronic health records within the OpenSAFELY-TPP platform in England, to study patient characteristics associated with clinically coded long COVID from 29 January 2020 to 31 March 2022. Method We summarised the distribution of characteristics for people with clinically coded long COVID. We estimated age-sex adjusted hazard ratios and fully adjusted hazard ratios for coded long COVID. Patient characteristics included demographic factors, and health behavioural and clinical factors. Results Among 17 986 419 adults, 36 886 (0.21%) were clinically coded with long COVID. Patient characteristics associated with coded long COVID included female sex, younger age (under 60 years), obesity, living in less deprived areas, ever smoking, greater consultation frequency, and history of diagnosed asthma, mental health conditions, pre-pandemic post-viral fatigue, or psoriasis. These associations were attenuated following two-doses of COVID-19 vaccines compared to before vaccination. Differences in the predictors of coded long COVID between the pre-vaccination and post-vaccination cohorts may reflect the different patient characteristics in these two cohorts rather than the vaccination status. Incidence of coded long COVID was higher in those with hospitalised COVID than with those non-hospitalised COVID-19. Conclusions We identified variation in coded long COVID by patient characteristic. Results should be interpreted with caution as long COVID was likely under-recorded in electronic health records
The genome sequence of the ichneumonid wasp, <i>Sussaba pulchella</i> (Holmgren, 1858) (Hymenoptera: Ichneumonidae)
Get PDFWe present a genome assembly from an individual male Sussaba pulchella (ichneumonid wasp; Arthropoda; Insecta; Hymenoptera; Ichneumonidae). The genome sequence has a total length of 299.91 megabases. Most of the assembly (81.88%) is scaffolded into 15 chromosomal pseudomolecules. The mitochondrial genome has also been assembled, with a length of 34.69 kilobases. This assembly was generated as part of the Darwin Tree of Life project, which produces reference genomes for eukaryotic species found in Britain and Ireland
Not Extremely Plastic: Testing the Limits of Morphological Plasticity in Fungal Mycelia in Response to Soil Grazers
Get PDFModular organisms such as fungi are assumed to exhibit extreme morphological plasticity, yet this assumption has rarely been tested experimentally. Their morphology emerges from local, independent responses of constituent modules, suggesting strong plastic responses to environmental conditions. While such levels of plasticity decouple morphology from ecological function, they make these organisms an ideal system for studying the evolution of plasticity. Here we quantified the plasticity of modular fungi to grazers with known strong effects on their fitness and tested two competing hypotheses: (1) fungal morphology converges on a common ‘grazing‐resistant’ phenotype across species (i.e., extreme plasticity) or (2) grazer‐induced plasticity remains limited and species‐specific. We found support for the latter, suggesting a more nuanced plasticity for fungi than would be expected based on their modularity. Our study calls for refining assumptions about plasticity in modular organisms and informs the use of morphological traits as predictors of ecological function
Mapping Changes in Settlement Number and Demography in the South of Israel from the Hellenistic to the Early Islamic Period
Get PDFThe south of Israel was lately at the heart of a debate regarding the supposed catastrophic effects of the Late Antique Little Ice Age (LALIA) and the Justinianic plague. The current article aims to contribute to this debate by examining the fluctuations in settlement numbers in the south of modern-day Israel, between the Hellenistic and Early Islamic periods. It will do this by aggregating archaeological survey data, mapping it on ArcGIS and analysing it quantitively and qualitatively, while comparing it with data from excavations. Through this, it will be shown that a decline in settlements occurred only from the 7th century CE and the damaging effects of the LALIA and the Justinianic plague will be questioned
Nature-Based Solutions to Promote Just Transitions for Climate Change and Antimicrobial Resistance: Reflections from Multisectoral Roundtables
Get PDFNature-based solutions (NbSs) are increasingly recognised for their potential to address climate change and biodiversity loss, but their role in mitigating antimicrobial resistance (AMR) remains underexplored. AMR and climate change share environmental drivers, such as pollution, ecosystem degradation, and industrial agriculture, yet responses often remain fragmented and technocratic. This paper draws on a global roundtable series convened under the British Academy’s “Just Transitions for AMR” initiative to explore how NbS can support more just, equitable, and integrated responses to these intersecting crises. Bringing together 46 experts from public health, environmental science, agriculture, governance, and social sciences, the roundtables facilitated interdisciplinary exchange across Africa, Asia, and Europe. The paper synthesises insights across four thematic areas: conceptualising Just Transitions in NbS, identifying co-benefits for scaling NbS for climate and AMR mitigation, addressing implementation barriers, and proposing future directions. Findings emphasise the need to reframe NbS as socially embedded practices co-designed with communities, rather than as technical fixes. Participants called for investment in place-based approaches, participatory monitoring, and governance structures promoting inclusion. The paper concludes by aligning NbS with One Health and Just Transition principles, urging a shift from isolated interventions to systems-oriented transformations that redress power imbalances in environmental and health governance