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Transforming jet flavour tagging at ATLAS
No full textJet flavour tagging enables the identification of jets originating from heavy-flavour quarks in proton–proton collisions at the Large Hadron Collider, playing a critical role in its physics programmes. This paper presents GN2, a transformer-based flavour tagging algorithm deployed by the ATLAS Collaboration that represents a different methodology compared to previous approaches. Designed to classify jets based on the flavour of their constituent particles, GN2 processes low-level tracking information in an end-to-end architecture and incorporates physics-informed auxiliary training objectives to enhance both interpretability and performance. Its performance is validated in both simulation and collision data. The measured c-jet (light-jet) rejection in data is improved by a factor of 3.5 (1.8) for a 70% b-jet tagging efficiency, compared to the previous algorithm. GN2 provides substantial benefits for physics analyses involving heavy-flavour jets, such as measurements of Higgs boson pair production and the couplings of bottom and charm quarks to the Higgs boson, and demonstrates the impact of advanced machine learning methods in experimental particle physics
An evaluation of a trauma-focused group intervention for women accessing a maternal mental health service
Get PDFBackground: Psychological birth trauma affects 1 in 3 women and 4–5% go on to develop childbirth-related post-traumatic stress disorder (CBPTSD). Maternal Mental Health Services (MMHS) have been established in the UK to provide psychological assessment and intervention for women experiencing CBPTSD following psychological birth trauma. CBPTSD symptoms can impact the transition to parenthood and the parent-infant relationship. Providing timely psychological intervention is therefore crucial in supporting women and families. Aims and Objective: This service evaluation aimed to evaluate a trauma-focused group intervention on reducing psychological distress and CBPTSD symptoms for women following psychological birth trauma in a MMHS. Method: The service evaluation included 30 women who attended a 6-week psychological intervention group. The group was facilitated online and included psychoeducation and grounding and stabilisation skills. Participants completed a range of self-report measures pre- and post-intervention that assessed psychological distress and CBPTSD symptoms. Participant therapy goals were also assessed. Results: Results indicated the group contributed to statistically significant reductions in psychological distress and CBPTSD symptoms, contributing to the growing evidence base for interventions following psychological birth trauma. There were also statistically significant differences in therapy goals following the group, indicating acceptability of the intervention. Conclusions: This service evaluation provides valuable insights into the role of group intervention for supporting women after psychological birth trauma within MMHS. Future research can build on this by replicating with larger samples to further explore efficacy and incorporate assessment of long-term change. Additionally, the efficacy and acceptability require exploration within more diverse samples
Breast Cancer Disparities in African and African-Ancestry Populations: Genetics, Epigenetics, Structural Barriers and Technology-Enabled Solutions
Get PDFBreast cancer remains a leading cause of mortality among women globally, with disproportionately high incidence, aggressive subtypes and poor outcomes in African and African-ancestry populations. While inherited BRCA1/BRCA2 mutations drive hereditary risk, recent evidence highlights the critical role of BRCA1 promoter methylation especially in sporadic and triple-negative breast cancers (TNBC), which disproportionately affect African-descended women. This review synthesises the genetic and epigenetic landscape of breast cancer susceptibility in African and diaspora cohorts, emphasising unique mutation spectra, elevated BRCA1 methylation frequencies and their prognostic/treatment implications. Systemic barriers including limited screening infrastructure, workforce shortages, structural racism, and cultural challenges exacerbate late diagnosis and inequities. We evaluate emerging solutions such as telemedicine, AI-enhanced diagnostics, and mobile platforms, alongside the need for context-specific research and investment to integrate molecular insights with innovative health system interventions. This synthesis underscores the urgency of addressing biological and structural drivers to close breast cancer outcome gaps in Africa and similar low- and middle-income settings
Components of Service Delivery Models of Care for the Detection, Care and Management of Visual Impairment for Adults and Children with Acquired Brain Injury: A Scoping Review Protocol
No full textIntroduction: Vision problems are common in patients with acquired brain injury (ABI). Inpatient eye care is ad hoc in the UK, and once patients with ABI are discharged from hospital care, community eye care provision is typically non-standardised and frequently leads to substantial unmet needs and health inequalities for patients. Objective: The objective of this scoping review is to identify and describe the components of existing service delivery models of care in relation to the detection, care and management of visual impairment for adults and children with ABI. This is a protocol; no results will be published in this manuscript. Methods: We will search multiple databases to include MEDLINE, CINAHL, Embase, APA PsycINFO and The Cochrane Library for English language publications from the Organisation for Economic Co-operation and Development (OECD) countries. Supplementary searches will also be conducted to locate grey literature. We will include any study that describes or assesses service delivery for adults and children with visual impairment following ABI in health and social care and education settings. Stakeholder Engagement: We consulted with a broad range of stakeholders, including subject experts from health and education sectors and patient and public representatives during the planning, and will continue the same during the conduct, reporting and dissemination of this scoping review
Imaging vascular characteristics and glycolytic metabolism of glioblastoma in a chick embryo model using 1H MRI and [18F]FDG-PET
No full textPurpose: To assess hypoxia-associated host-tumour vascular adaptations and glycolytic metabolism in the chick chorioallantoic membrane (CAM) glioblastoma model. Procedures: U251 GBM cells were conditioned under normoxia (21% O₂) or hypoxia (1% O₂) for 72 h before implantation onto the CAM on embryonic day 7 (E7). Imaging was performed on E13 using MRI (control-CAM n = 8, normoxic-tumour n = 7, hypoxic-tumour n = 6) and brightfield microscopy (control-CAM n = 7, normoxic-tumour n = 8, hypoxic-tumour n = 7). Tumours were harvested on E14 for histology and gene expression analyses. In a separate cohort of 25 GBM-CAM tumours grown under normoxic conditioning, the correlation of glucose metabolism was assessed using [18F]FDG-PET on E12 followed by lactate MRS on E13 (n = 8). Results: Normoxia- and hypoxia-conditioned tumour-bearing CAMs exhibited vascular remodelling and significant upregulation of VEGFA and ADM compared to cultured cells. αSMA staining confirmed vessel infiltration in normoxia-conditioned tumours. CAIX staining revealed a hypoxic core in these tumours while hypoxia-conditioned tumours displayed heterogeneous staining. In both conditions, GLUT1 staining colocalised with CAIX staining, indicating hypoxia-associated glycolysis. GLUT1, PDK1 and LDHA expression was elevated in CAM tumours relative to tumour cells in vitro. In the metabolic imaging cohort, most tumours exhibited [18F]FDG uptake and lactate signal. However, no statistically significant relationship was observed between the two methods. Conclusions: The CAM model provides a versatile platform for investigating GBM vascularisation and metabolism. Hypoxic conditioning amplifies transcriptional and vascular changes to the CAM. Although both [18F]FDG uptake and lactate were measurable, no significant correlation between the two was observed, potentially reflecting variability in tumour engraftment, vascular delivery of [18F]FDG, and microenvironmental influences on lactate accumulation
Transcriptional Control of Hepatocellular Carcinoma Cells Aggressiveness by AAV2/8-Mediated Delivery of Human Centenarian-Associated SIRT6 N308K/A313S.
Get PDFHepatocellular carcinoma (HCC) is the sixth most prevalent cancer and a chief cause of cancer-related mortality throughout the world. SIRT6 is a fundamental sirtuin that governs several disease processes encompassing inflammation and cancer, including HCC. Longevity in centenarian Ashkenazi Jews was recently associated to novel allelic variants of SIRT6 (N308K/A313S), which ameliorate genome maintenance and DNA repair, and suppress cancer cells. It is currently unknown whether the above-mentioned SIRT6 variants display divergent or similar roles in HCC pathogenesis, compared to the wild-type (WT) counterpart. Our goal was to elucidate how these new centenarian-associated SIRT6 genetic variants may modulate HCC cell lines' (HepG2 and Huh-7) aggressiveness and behavior, using functional and transcriptomic approaches. We demonstrate that adeno-associated virus (AAV2/8)-mediated overexpression of centenarian-associated SIRT6 variants hampered HCC cell proliferation, with transcriptomic data showing the modulation of hallmark genes involved in the turnover of collagen/extracellular matrix (ECM). In addition, we found that AAV2/8-mediated overexpression of SIRT6 N308K/A313S decreased invasion and also increased stiffness in HCC cells, as measured by nanoindentation, in a more pronounced fashion compared to SIRT6 WT. Intracellular stiffness is a property of the cancer cells themselves, which, along with ECM invasiveness, plays a significant role in the progression of HCC. These data suggest that increased intracellular stiffening mirrors increased cell motility and invasive behavior; it can be indicative of suppressed cancer development and progression by the centenarian-associated SIRT6 N308K/A313S mutant
Short-term lagged interactions between freight and passenger volumes in urban traffic: inter- and intra-modal effects with explainable machine learning
Get PDFUrban transport systems face increasing complexity as freight and passenger flows compete for limited road capacity. While multimodal forecasting methods have progressed, short-term interactions between vehicle classes remain underexplored, particularly in real-world operational settings. This study addresses that gap by examining whether recent freight or passenger volumes are significantly associated with current traffic conditions across modes. Using 6,003 hourly records from Liverpool, UK, we develop an interpretable machine learning framework combining K-means clustering, XGBoost classification, and the DALEX explainability toolkit. Results show that one-hour lagged freight volume significantly improves the classification of current passenger traffic states, while the reverse effect is limited. Global feature importance and local interpretability analyses consistently identify freight volume as the most influential predictor. Partial dependence plots (PDPs) reveal a nonlinear inflexion point, where freight volumes exceeding roughly 500 vehicles per hour in this Liverpool case study are associated with reduced passenger flow. McNemar's test confirms a statistically significant improvement, and robustness checks, including alternative lag structures, interaction terms, and reciprocal models, reinforce the stability of this finding. These insights offer practical value for short-term forecasting, corridor-level coordination, and longer-term multimodal planning. The observed directional asymmetry, wherein freight volumes more reliably predict passenger conditions than the reverse, highlights the potential benefits of incorporating freight data into real-time traffic management systems. More broadly, the study demonstrates how interpretable machine learning can uncover cross-modal dependencies and support the development of more integrated, responsive, and equitable urban mobility systems
Continental Contrasts in Climate Extremes That Control Tree Fecundity
Get PDFIn 2023, more than half of olive harvests (Olea europaea) across Spain, Greece, and Türkiye were lost to drought. The same year late freeze destroyed 90% of the peach crop (Prunus persica) on the Georgia Piedmont and the apple crop (Malus domestica) in central New York, Vermont, and southern Quebec. Climate extremes now rank with the costliest threats to agriculture, but their role in forest recovery from diebacks that are happening globally is unknown for lack of tree fecundity estimates in forests. Tolerance of climate extremes could depend on past exposure but constrained by phylogenetic conservatism. We report a continental scale analysis of climate extremes and forest fecundity across North America and Europe showing that responses to late freeze and drought are happening now. Species differences are not explained by the traits typically included in ecological studies and they are weakly associated with phylogeny. Late freeze, that is, freezing temperatures that follow the onset of flower development in spring, is shown to be “normal” in North America, but not Europe, potentially explaining failed seed production due to delayed onset and the resultant shorter growing period by North American transplants dating back at least to the 18th century. Drought has thus far had the greatest impacts in dry forested regions, but here too, species differences are not explained by traditional trait values. If responses have been buffered from drought and late freeze by past exposure, acclimation and local adaptation prove inadequate as extremes intensify
Measurement of the branching fraction of the Λb0→J/ψΛ decay and isospin asymmetry of B → J/ψK decays
No full textThis paper describes a measurement of the Λb0→J/ψΛ branching fraction using data collected with the LHCb experiment in proton-proton collisions from 2016 to 2018. The dataset corresponds to an integrated luminosity of 5.4 fb−1. The branching fraction is determined relative to that of B0→J/ψKS0 decays, (Formula presented.) yielding BΛb0→J/ψΛ=3.34±0.02±0.10±0.08±0.28×10−4, where the first uncertainty is statistical, the second systematic, the third due to external inputs on branching fractions and the fourth due to the ratio of Λb0 baryon and B0 meson hadronisation fractions. In addition, the isospin asymmetry between the rates of B0→J/ψKS0 and B+→ J/ψK+ decays is measured to be (Formula presented.) where the first uncertainty is statistical and the second systematic
Learning-Based Multi-Objective Optimization of Parametric Stadium-Type Tiered-Seating Configurations
No full textParametric tiered-seating design can be framed as a constrained multi-objective optimization problem in which a low-dimensional decision vector is evaluated by a deterministic operator with sequential feasibility rejection and visibility constraints. This study introduces an oracle-preserving, learning-assisted screening workflow, where a multi-output multilayer perceptron (MLP) is used only to prioritize candidates for evaluation. Here, multi-output denotes a single network trained to predict the full objective vector jointly. Candidates are sampled within bounded decision ranges and evaluated by an operator that propagates section-coupled geometric state and enforces hard clearance thresholds through a Vertical Sightline System (VSS), i.e., a deterministic row-wise sightline/clearance evaluator that enforces hard clearance thresholds. The oracle-evaluated set is reduced to its mixed-direction Pareto-efficient subset and filtered by feature-space proximity to a fixed validation reference using nearest-neighbor distances in standardized 11-dimensional features, yielding a robustness-oriented pool. A compact shortlist is derived via TOPSIS (Technique for Order Preference by Similarity to an Ideal Solution; used here strictly as a post-Pareto decision-support ranking rule), and preference uncertainty is assessed by Monte Carlo weight sampling from a symmetric Dirichlet distribution. In an archived run under a fixed oracle budget, 1235 feasible designs are evaluated, producing 934 evaluated Pareto solutions; proximity filtering retains 187 robust candidates and TOPSIS reports a traceable top-30 shortlist. Stability is supported by concentrated top-k frequencies under weight perturbations and by audits under single-feature-drop ablations and tested rounding precisions. Overall, the workflow enables reproducible multi-objective screening and reporting for feasibility-dominated seating design
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