Study of High-Transverse-Momentum Higgs Boson Production in Association with a Vector Boson in the qqbb Final State with the ATLAS Detector

This Letter presents the first study of Higgs boson production in association with a vector boson (V=W or Z) in the fully hadronic qqbb final state using data recorded by the ATLAS detector at the LHC in proton-proton collisions at sqrt[s]=13  TeV and corresponding to an integrated luminosity of 137  fb^{-1}. The vector bosons and Higgs bosons are each reconstructed as large-radius jets and tagged using jet substructure techniques. Dedicated tagging algorithms exploiting b-tagging properties are used to identify jets consistent with Higgs bosons decaying into bb[over ¯]. Dominant backgrounds from multijet production are determined directly from the data, and a likelihood fit to the jet mass distribution of Higgs boson candidates is used to extract the number of signal events. The VH production cross section is measured inclusively and differentially in several ranges of Higgs boson transverse momentum: 250-450, 450-650, and greater than 650 GeV. The inclusive signal yield relative to the standard model expectation is observed to be μ=1.4_{-0.9}^{+1.0} and the corresponding cross section is 3.1±1.3(stat)_{-1.4}^{+1.8}(syst)  pb.

Measurement of the Centrality Dependence of the Dijet Yield in p+Pb Collisions at sqrt[s_{NN}]=8.16 TeV with the ATLAS Detector

ATLAS measured the centrality dependence of the dijet yield using 165  nb^{-1} of p+Pb data collected at sqrt[s_{NN}]=8.16  TeV in 2016. The event centrality, which reflects the p+Pb impact parameter, is characterized by the total transverse energy registered in the Pb-going side of the forward calorimeter. The central-to-peripheral ratio of the scaled dijet yields, R_{CP}, is evaluated, and the results are presented as a function of variables that reflect the kinematics of the initial hard parton scattering process. The R_{CP} shows a scaling with the Bjorken x of the parton originating from the proton, x_{p}, while no such trend is observed as a function of x_{Pb}. This analysis provides unique input to understanding the role of small proton spatial configurations in p+Pb collisions by covering parton momentum fractions from the valence region down to x_{p}∼10^{-3} and x_{Pb}∼4×10^{-4}.

Validation of metastasis-free survival as a surrogate endpoint for overall survival in localized prostate cancer in the era of docetaxel for castration-resistant prostate cancer

BACKGROUND

Prior work from the Intermediate Clinical Endpoints in Cancer of the Prostate (ICECaP) consortium (ICECaP-1) demonstrated that metastasis-free survival (MFS) is a valid surrogate for overall survival (OS) in localized prostate cancer (PCa). This was based on data from patients treated predominantly before 2004, prior to docetaxel being available for the treatment of metastatic castrate-resistant prostate cancer (mCRPC). We sought to validate surrogacy in a more contemporary era (ICECaP-2) with greater availability of docetaxel and other systemic therapies for mCRPC.

PATIENTS AND METHODS

Eligible trials for ICECaP-2 were those providing individual patient data (IPD) after publication of ICECaP-1 and evaluating adjuvant/salvage therapy for localized PCa, and which collected MFS and OS data. MFS was defined as distant metastases or death from any cause, and OS was defined as death from any cause. Surrogacy was evaluated using a meta-analytic two-stage validation model, with an R2 ≥ 0.7 defined a priori as clinically relevant.

RESULTS

A total of 15 164 IPD from 14 trials were included in ICECaP-2, with 70% of patients treated after 2004. The median follow-up was 8.3 years and the median postmetastasis survival was 3.1 years in ICECaP-2, compared with 1.9 years in ICECaP-1. For surrogacy condition 1, Kendall's tau was 0.92 for MFS with OS at the patient level, and R2 from weighted linear regression (WLR) of 8-year OS on 5-year MFS was 0.73 (95% confidence interval 0.53-0.82) at the trial level. For condition 2, R2 was 0.83 (95% confidence interval 0.64-0.89) from WLR of log[hazard ratio (HR)]-OS on log(HR)-MFS. The surrogate threshold effect on OS was an HR(MFS) of 0.81.

CONCLUSIONS

MFS remained a valid surrogate for OS in a more contemporary era, where patients had greater access to docetaxel and other systemic therapies for mCRPC. This supports the use of MFS as the primary outcome measure for ongoing adjuvant trials in localized PCa.

Search for New Phenomena in Two-Body Invariant Mass Distributions Using Unsupervised Machine Learning for Anomaly Detection at sqrt[s]=13 TeV with the ATLAS Detector

Searches for new resonances are performed using an unsupervised anomaly-detection technique. Events with at least one electron or muon are selected from 140  fb^{-1} of pp collisions at sqrt[s]=13  TeV recorded by ATLAS at the Large Hadron Collider. The approach involves training an autoencoder on data, and subsequently defining anomalous regions based on the reconstruction loss of the decoder. Studies focus on nine invariant mass spectra that contain pairs of objects consisting of one light jet or b jet and either one lepton (e,μ), photon, or second light jet or b jet in the anomalous regions. No significant deviations from the background hypotheses are observed. Limits on contributions from generic Gaussian signals with various widths of the resonance mass are obtained for nine invariant masses in the anomalous regions.

Observation of WZγ Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WZγ production and a measurement of its cross section using 140.1±1.2  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. The WZγ production cross section, with both the W and Z bosons decaying leptonically, pp→WZγ→ℓ^{'}^{±}νℓ^{+}ℓ^{-}γ (ℓ^{(^{'})}=e, μ), is measured in a fiducial phase-space region defined such that the leptons and the photon have high transverse momentum and the photon is isolated. The cross section is found to be 2.01±0.30(stat)±0.16(syst)  fb. The corresponding standard model predicted cross section calculated at next-to-leading order in perturbative quantum chromodynamics and at leading order in the electroweak coupling constant is 1.50±0.06  fb. The observed significance of the WZγ signal is 6.3σ, compared with an expected significance of 5.0σ.

Predation risk drives long-term shifts in migratory behaviour and demography in a large herbivore population

Migration is an adaptive life-history strategy across taxa that helps individuals maximise fitness by obtaining forage and avoiding predation risk. The mechanisms driving migratory changes are poorly understood, and links between migratory behaviour, space use, and demographic consequences are rare. Here, we use a nearly 20-year record of individual-based monitoring of a large herbivore, elk (Cervus canadensis) to test hypotheses for changing patterns of migration in and adjacent to a large protected area in Banff National Park (BNP), Canada. We test whether bottom-up (forage quality) or top-down (predation risk) factors explained trends in (i) the proportion of individuals using 5 different migratory tactics, (ii) differences in survival rates of migratory tactics during migration and whilst on summer ranges, (iii) cause-specific mortality by wolves and grizzly bears, and (iv) population abundance. We found dramatic shifts in migration consistent with behavioural plasticity in individual choice of annual migratory routes. Shifts were inconsistent with exposure to the bottom-up benefits of migration. Instead, exposure to landscape gradients in predation risk caused by exploitation outside the protected area drove migratory shifts. Carnivore exploitation outside the protected area led to higher survival rates for female elk remaining resident or migrating outside the protected area. Cause-specific mortality aligned with exposure to predation risk along migratory routes and summer ranges. Wolf predation risk was higher on migratory routes than summer ranges of montane-migrant tactics, but wolf predation risk traded-off with heightened risk from grizzly bears on summer ranges. A novel eastern migrant tactic emerged following a large forest fire that enhanced forage in an area with lower predation risk outside of the protected area. The changes in migratory behaviour translated to population abundance, where abundance of the montane-migratory tactics declined over time. The presence of diverse migratory life histories maintained a higher total population abundance than would have been the case with only one migratory tactic in the population. Our study demonstrates the complex ways in which migratory populations change over time through behavioural plasticity and associated demographic consequences because of individuals balancing predation risk and forage trade-offs.

Combined Measurement of the Higgs Boson Mass from the H→γγ and H→ZZ^{*}→4ℓ Decay Channels with the ATLAS Detector Using sqrt[s]=7, 8, and 13 TeV pp Collision Data

A measurement of the mass of the Higgs boson combining the H→ZZ^{*}→4ℓ and H→γγ decay channels is presented. The result is based on 140  fb^{-1} of proton-proton collision data collected by the ATLAS detector during LHC run 2 at a center-of-mass energy of 13 TeV combined with the run 1 ATLAS mass measurement, performed at center-of-mass energies of 7 and 8 TeV, yielding a Higgs boson mass of 125.11±0.09(stat)±0.06(syst)=125.11±0.11  GeV. This corresponds to a 0.09% precision achieved on this fundamental parameter of the Standard Model of particle physics.

Search for Dark Photons in Rare Z Boson Decays with the ATLAS Detector

A search for events with a dark photon produced in association with a dark Higgs boson via rare decays of the standard model Z boson is presented, using 139  fb^{-1} of sqrt[s]=13  TeV proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider. The dark boson decays into a pair of dark photons, and at least two of the three dark photons must each decay into a pair of electrons or muons, resulting in at least two same-flavor opposite-charge lepton pairs in the final state. The data are found to be consistent with the background prediction, and upper limits are set on the dark photon's coupling to the dark Higgs boson times the kinetic mixing between the standard model photon and the dark photon, α_{D}ϵ^{2}, in the dark photon mass range of [5, 40] GeV except for the ϒ mass window [8.8, 11.1] GeV. This search explores new parameter space not previously excluded by other experiments.

Observation of Single-Top-Quark Production in Association with a Photon Using the ATLAS Detector

This Letter reports the observation of single top quarks produced together with a photon, which directly probes the electroweak coupling of the top quark. The analysis uses 139  fb^{-1} of 13 TeV proton-proton collision data collected with the ATLAS detector at the Large Hadron Collider. Requiring a photon with transverse momentum larger than 20 GeV and within the detector acceptance, the fiducial cross section is measured to be 688±23(stat) _{-71}^{+75}(syst)  fb, to be compared with the standard model prediction of 515_{-42}^{+36}  fb at next-to-leading order in QCD.

The incidence and burden of injury in male adolescent community rugby union in Australia

OBJECTIVES

To describe the incidence, location, mechanism and burden of injury in community male adolescent rugby.

METHODS

A prospective cohort injury surveillance study using sports trainers to record 'any physical complaint' over three seasons (2018/2019/2021) in 979 U13-U17 community male rugby union players.

RESULTS

One hundred and fifty-two time-loss injuries (27.6/1000 hours) with an associated burden of 2313 days (419.7 days/1000 hours), 169 non-time loss medical attention (30.1/1000 hours) and 813 physical complaints (147.5/1000 hours) were recorded from 5511.7 exposure hours (matches 3932.5 hours, training 1579.2 hours). Time-loss injury incidence was highest in U16 (45/1000 hours) and lowest in U17 (16.6/1000 hours), with U17 significantly lower than U16 and U15 age-grades (p < 0.05). Injury burden was greatest in U13 (561.4 days/1000 hours), and significantly higher than U15 and U17 (p < 0.05). Collectively, injury incidence was greatest for the head/neck (11.8/1000 hours), bruise/contusions were most common (8.7/1000 hours) and concussion (4.5/1000 hours) accounted for the greatest injury burden (102 days/1000 hours). Being tackled was the most observed injury mechanism (10.0/1000 hours). Forwards had significantly higher incidence in mild injury (p < 0.01). The total burden (p < 0.001) associated with mild (p < 0.001) and moderate injuries (p < 0.001) was significantly higher in forwards, as was the burden of being tackled (p < 0.001), collisions (p < 0.001), trunk (p < 0.001) and lower limb (p < 0.01) injury locations. In contrast, ruck-related injury burden was greater in backs (p < 0.001).

CONCLUSION

This study showed age-grade and positional differences in incidence and burden of injury in community adolescent rugby union. The rate of non-time loss relative to time-loss injury and muscle strain injury in U13-U14s suggests further research into injury risk and maturation in rugby is needed.

Measurement of Suppression of Large-Radius Jets and Its Dependence on Substructure in Pb+Pb Collisions at sqrt[s_{NN}]=5.02 TeV with the ATLAS Detector

This letter presents a measurement of the nuclear modification factor of large-radius jets in sqrt[s_{NN}]=5.02  TeV Pb+Pb collisions by the ATLAS experiment. The measurement is performed using 1.72  nb^{-1} and 257  pb^{-1} of Pb+Pb and pp data, respectively. The large-radius jets are reconstructed with the anti-k_{t} algorithm using a radius parameter of R=1.0, by reclustering anti-k_{t} R=0.2 jets, and are measured over the transverse momentum (p_{T}) kinematic range of 158 Collapse

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Measurement of the Sensitivity of Two-Particle Correlations in pp Collisions to the Presence of Hard Scatterings

A key open question in the study of multiparticle production in high-energy pp collisions is the relationship between the "ridge"-i.e., the observed azimuthal correlations between particles in the underlying event that extend over all rapidities-and hard or semihard scattering processes. In particular, it is not known whether jets or their soft fragments are correlated with particles in the underlying event. To address this question, two-particle correlations are measured in pp collisions at sqrt[s]=13  TeV using data collected by the ATLAS experiment at the LHC, with an integrated luminosity of 15.8  pb^{-1}, in two different configurations. In the first case, charged particles associated with jets are excluded from the correlation analysis, while in the second case, correlations are measured between particles within jets and charged particles from the underlying event. Second-order flow coefficients, v_{2}, are presented as a function of event multiplicity and transverse momentum. These measurements show that excluding particles associated with jets does not affect the measured correlations. Moreover, particles associated with jets do not exhibit any significant azimuthal correlations with the underlying event, ruling out hard processes contributing to the ridge.

Observation of an Excess of Dicharmonium Events in the Four-Muon Final State with the ATLAS Detector

A search is made for potential ccc[over ¯]c[over ¯] tetraquarks decaying into a pair of charmonium states in the four muon final state using proton-proton collision data at sqrt[s]=13  TeV, corresponding to an integrated luminosity of 140  fb^{-1} recorded by the ATLAS experiment at LHC. Two decay channels, J/ψ+J/ψ→4μ and J/ψ+ψ(2S)→4μ, are studied. Backgrounds are estimated based on a hybrid approach involving Monte Carlo simulations and data-driven methods. Statistically significant excesses with respect to backgrounds dominated by the single parton scattering are seen in the di-J/ψ channel consistent with a narrow resonance at 6.9 GeV and a broader structure at lower mass. A statistically significant excess is also seen in the J/ψ+ψ(2S) channel. The fitted masses and decay widths of the structures are reported.

Observation of the γγ→ττ Process in Pb+Pb Collisions and Constraints on the τ-Lepton Anomalous Magnetic Moment with the ATLAS Detector

This Letter reports the observation of τ-lepton-pair production in ultraperipheral lead-lead collisions Pb+Pb→Pb(γγ→ττ)Pb and constraints on the τ-lepton anomalous magnetic moment a_{τ}. The dataset corresponds to an integrated luminosity of 1.44  nb^{-1} of LHC Pb+Pb collisions at sqrt[s_{NN}]=5.02  TeV recorded by the ATLAS experiment in 2018. Selected events contain one muon from a τ-lepton decay, an electron or charged-particle track(s) from the other τ-lepton decay, little additional central-detector activity, and no forward neutrons. The γγ→ττ process is observed in Pb+Pb collisions with a significance exceeding 5 standard deviations and a signal strength of μ_{ττ}=1.03_{-0.05}^{+0.06} assuming the standard model value for a_{τ}. To measure a_{τ}, a template fit to the muon transverse-momentum distribution from τ-lepton candidates is performed, using a dimuon (γγ→μμ) control sample to constrain systematic uncertainties. The observed 95% confidence-level interval for a_{τ} is -0.057 Collapse

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Strong Constraints on Jet Quenching in Centrality-Dependent p+Pb Collisions at 5.02 TeV from ATLAS

Jet quenching is the process of color-charged partons losing energy via interactions with quark-gluon plasma droplets created in heavy-ion collisions. The collective expansion of such droplets is well described by viscous hydrodynamics. Similar evidence of collectivity is consistently observed in smaller collision systems, including pp and p+Pb collisions. In contrast, while jet quenching is observed in Pb+Pb collisions, no evidence has been found in these small systems to date, raising fundamental questions about the nature of the system created in these collisions. The ATLAS experiment at the Large Hadron Collider has measured the yield of charged hadrons correlated with reconstructed jets in 0.36  nb^{-1} of p+Pb and 3.6  pb^{-1} of pp collisions at 5.02 TeV. The yields of charged hadrons with p_{T}^{ch}>0.5  GeV near and opposite in azimuth to jets with p_{T}^{jet}>30 or 60 GeV, and the ratios of these yields between p+Pb and pp collisions, I_{pPb}, are reported. The collision centrality of p+Pb events is categorized by the energy deposited by forward neutrons from the struck nucleus. The I_{pPb} values are consistent with unity within a few percent for hadrons with p_{T}^{ch}>4  GeV at all centralities. These data provide new, strong constraints that preclude almost any parton energy loss in central p+Pb collisions.

Search for Heavy Neutral Leptons in Decays of W Bosons Using a Dilepton Displaced Vertex in sqrt[s]=13 TeV pp Collisions with the ATLAS Detector

A search for a long-lived, heavy neutral lepton (N) in 139  fb^{-1} of sqrt[s]=13  TeV pp collision data collected by the ATLAS detector at the Large Hadron Collider is reported. The N is produced via W→Nμ or W→Ne and decays into two charged leptons and a neutrino, forming a displaced vertex. The N mass is used to discriminate between signal and background. No signal is observed, and limits are set on the squared mixing parameters of the N with the left-handed neutrino states for the N mass range 3  GeV Collapse

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Test of CP Invariance in Higgs Boson Vector-Boson-Fusion Production Using the H→γγ Channel with the ATLAS Detector

A test of CP invariance in Higgs boson production via vector-boson fusion has been performed in the H→γγ channel using 139  fb^{-1} of proton-proton collision data at sqrt[s]=13  TeV collected by the ATLAS detector at the LHC. The optimal observable method is used to probe the CP structure of interactions between the Higgs boson and electroweak gauge bosons, as described by an effective field theory. No sign of CP violation is observed in the data. Constraints are set on the parameters describing the strength of the CP-odd component in the coupling between the Higgs boson and the electroweak gauge bosons in two effective field theory bases: d[over ˜] in the HISZ basis and c_{HW[over ˜]} in the Warsaw basis. The results presented are the most stringent constraints on CP violation in the coupling between Higgs and weak bosons. The 95% C.L. constraint on d[over ˜] is derived for the first time and the 95% C.L. constraint on c_{HW[over ˜]} has been improved by a factor of 5 compared to the previous measurement.

Issue 2 - "Update on adverse respiratory effects of indoor air pollution". Part 2): Indoor air pollution and respiratory diseases: Perspectives from Italy and some other GARD countries

OBJECTIVE

to synthesize the Italian epidemiological contribution to knowledge on indoor pollution respiratory impact, and to analyze the perspective of some GARD countries on the health effects of indoor air pollution.

RESULTS

Italian epidemiological analytical studies confirmed a strong relationship between indoor air pollution and health in general population. Environmental tobacco smoke, biomass (wood/coal) fuel for cooking/heating and indoor allergens (house dust mites, cat and dog dander, mold/damp) are the most relevant indoor pollution sources and are related to respiratory and allergic symptoms/diseases in Italy and in other GARD countries such as Mexico, Brazil, Vietnam, India, Nepal and Kyrgyzstan. Community-based global health collaborations are working to improve prevention, diagnosis and care of respiratory diseases around the world, specially in low- and middle-income countries, through research and education.

CONCLUSIONS

in the last thirty years, the scientific evidence produced on respiratory health effects of indoor air pollution has been extensive, but the necessity to empower the synergies between scientific community and local administrations remains a challenge to address in order to implement effective interventions. Based on abundant evidence of indoor pollution health effect, WHO, scientific societies, patient organizations and other members of the health community should work together to pursue the GARD vision of "a world where all people breathe freely" and encourage policy makers to increase their engagement in advocacy for clean air.

Rhinitis associated with asthma is distinct from rhinitis alone: The ARIA-MeDALL hypothesis

Asthma, rhinitis and atopic dermatitis (AD) are interrelated clinical phenotypes that partly overlap in the human interactome. The concept of "one-airway-one-disease", coined over 20 years ago, is a simplistic approach of the links between upper- and lower-airway allergic diseases. With new data, it is time to reassess the concept. This article reviews (i) the clinical observations that led to Allergic Rhinitis and its Impact on Asthma (ARIA), (ii) new insights into polysensitisation and multimorbidity, (iii) advances in mHealth for novel phenotype definition, (iv) confirmation in canonical epidemiologic studies, (v) genomic findings, (vi) treatment approaches and (vii) novel concepts on the onset of rhinitis and multimorbidity. One recent concept, bringing together upper- and lower-airway allergic diseases with skin, gut and neuropsychiatric multimorbidities, is the "Epithelial Barrier Hypothesis". This review determined that the "one-airway-one-disease" concept does not always hold true and that several phenotypes of disease can be defined. These phenotypes include an extreme "allergic" (asthma) phenotype combining asthma, rhinitis and conjunctivitis. Rhinitis alone and rhinitis and asthma multimorbidity represent two distinct diseases with the following differences: (i) genomic and transcriptomic background (Toll-Like Receptors and IL-17 for rhinitis alone as a local disease; IL-33 and IL-5 for allergic and non-allergic multimorbidity as a systemic disease), (ii) allergen sensitisation patterns (mono- or pauci-sensitisation versus polysensitisation), (iii) severity of symptoms and (iv) treatment response. In conclusion, rhinitis alone (local disease) and rhinitis with asthma multimorbidity (systemic disease) should be considered as two distinct diseases, possibly modulated by the microbiome, and may be a model for understanding the epidemics of chronic and auto-immune diseases.

The therapeutic and commercial landscape of stem cell vesicles in regenerative dermatology

Extracellular vesicles (EVs) are lipid enveloped nanoparticles that are naturally produced by cells and function in the intercellular transfer of biological material such as proteins, RNAs and metabolites. They have been shown to act in an autocrine and paracrine manner to alter the functions of local and distant recipient cells, with a growing body of evidence highlighting their wide-ranging functions in regenerative processes such as stem cell maintenance, tissue repair and immune modulation. EVs offer several potential advantages over stem cell therapies such as improved safety profiles, scalability, and enhanced storage and quality control of the final product. In fact, many of the pro-regenerative outcomes of stem cell therapies have been attributed to the release of mesenchymal stem cell-derived EVs (MSC-EVs) and their potent effects on extracellular matrix turnover, local cell recruitment, proliferation and angiogenesis is now well described. These positive outcomes have led to clinical trials assessing the safety of MSC-EVs for applications in wound healing and the treatment of cutaneous ulcers, as well as the emergence of multiple commercial MSC-EV sources marketed for topical application in cosmetic medicine. However, regenerative EV therapeutics remain in their infancy and pertinent questions regarding product standardisation, potency and the regulatory landscape surrounding the development of these promising nano-therapeutics must be addressed to ensure safe and effective clinical adoption. In this article we provide an overview of the emerging landscape of MSC-EVs in regenerative dermatology and cosmetic science, highlighting the underlying biological mechanisms pertinent to their application and providing a perspective on current safety considerations, regulation and future directions in the field.

Shark depredation: future directions in research and management

Shark depredation is a complex social-ecological issue that affects a range of fisheries worldwide. Increasing concern about the impacts of shark depredation, and how it intersects with the broader context of fisheries management, has driven recent research in this area, especially in Australia and the United States. This review synthesises these recent advances and provides strategic guidance for researchers aiming to characterise the occurrence of depredation, identify the shark species responsible, and test deterrent and management approaches to reduce its impacts. Specifically, the review covers the application of social science approaches, as well as advances in video camera and genetic methods for identifying depredating species. The practicalities and considerations for testing magnetic, electrical, and acoustic deterrent devices are discussed in light of recent research. Key concepts for the management of shark depredation are reviewed, with recommendations made to guide future research and policy development. Specific management responses to address shark depredation are lacking, and this review emphasizes that a "silver bullet" approach for mitigating depredation does not yet exist. Rather, future efforts to manage shark depredation must rely on a diverse range of integrated approaches involving those in the fishery (fishers, scientists and fishery managers), social scientists, educators, and other stakeholders.

Accuracy and economic evaluation of screening tests for undiagnosed COPD among hypertensive individuals in Brazil

In Brazil, prevalence of diagnosed COPD among adults aged 40 years and over is 16% although over 70% of cases remain undiagnosed. Hypertension is common and well-recorded in primary care, and frequently co-exists with COPD because of common causes such as tobacco smoking, therefore we conducted a cross-sectional screening test accuracy study in nine Basic Health Units in Brazil, among hypertensive patients aged ≥40 years to identify the optimum screening test/combinations to detect undiagnosed COPD. We compared six index tests (four screening questionnaires, microspirometer and peak flow) against the reference test defined as those below the lower limit of normal (LLN-GLI) on quality diagnostic spirometry, with confirmed COPD at clinical review. Of 1162 participants, 6.8% (n = 79) had clinically confirmed COPD. Peak flow had a higher specificity but lower sensitivity than microspirometry (sensitivity 44.3% [95% CI 33.1, 55.9], specificity 95.5% [95% CI 94.1, 96.6]). SBQ performed well compared to the other questionnaires (sensitivity 75.9% [95% CI 65.0, 84.9], specificity 59.2% [95% CI 56.2, 62.1]). A strategy requiring both SBQ and peak flow to be positive yielded sensitivity of 39.2% (95% CI 28.4, 50.9) and specificity of 97.0% (95% CI 95.7, 97.9). The use of simple screening tests was feasible within the Brazilian primary care setting. The combination of SBQ and peak flow appeared most efficient, when considering performance of the test, cost and ease of use (costing £1690 (5554 R$) with 26.7 cases detected per 1,000 patients). However, the choice of screening tests depends on the clinical setting and availability of resources.ISRCTN registration number: 11377960.

Short-term risk prediction after major lower limb amputation: PERCEIVE study

BACKGROUND

The accuracy with which healthcare professionals (HCPs) and risk prediction tools predict outcomes after major lower limb amputation (MLLA) is uncertain. The aim of this study was to evaluate the accuracy of predicting short-term (30 days after MLLA) mortality, morbidity, and revisional surgery.

METHODS

The PERCEIVE (PrEdiction of Risk and Communication of outcomE following major lower limb amputation: a collaboratIVE) study was launched on 1 October 2020. It was an international multicentre study, including adults undergoing MLLA for complications of peripheral arterial disease and/or diabetes. Preoperative predictions of 30-day mortality, morbidity, and MLLA revision by surgeons and anaesthetists were recorded. Probabilities from relevant risk prediction tools were calculated. Evaluation of accuracy included measures of discrimination, calibration, and overall performance.

RESULTS

Some 537 patients were included. HCPs had acceptable discrimination in predicting mortality (931 predictions; C-statistic 0.758) and MLLA revision (565 predictions; C-statistic 0.756), but were poor at predicting morbidity (980 predictions; C-statistic 0.616). They overpredicted the risk of all outcomes. All except three risk prediction tools had worse discrimination than HCPs for predicting mortality (C-statistics 0.789, 0.774, and 0.773); two of these significantly overestimated the risk compared with HCPs. SORT version 2 (the only tool incorporating HCP predictions) demonstrated better calibration and overall performance (Brier score 0.082) than HCPs. Tools predicting morbidity and MLLA revision had poor discrimination (C-statistics 0.520 and 0.679).

CONCLUSION

Clinicians predicted mortality and MLLA revision well, but predicted morbidity poorly. They overestimated the risk of mortality, morbidity, and MLLA revision. Most short-term risk prediction tools had poorer discrimination or calibration than HCPs. The best method of predicting mortality was a statistical tool that incorporated HCP estimation.

Improving access to affordable quality-assured inhaled medicines in low- and middle-income countries

BACKGROUND: Access to affordable inhaled medicines for chronic respiratory diseases (CRDs) is severely limited in low- and middle-income countries (LMICs), causing avoidable morbidity and mortality. The International Union Against Tuberculosis and Lung Disease convened a stakeholder meeting on this topic in February 2022.METHODS: Focused group discussions were informed by literature and presentations summarising experiences of obtaining inhaled medicines in LMICs. The virtual meeting was moderated using a topic guide around barriers and solutions to improve access. The thematic framework approach was used for analysis.RESULTS: A total of 58 key stakeholders, including patients, healthcare practitioners, members of national and international organisations, industry and WHO representatives attended the meeting. There were 20 pre-meeting material submissions. The main barriers identified were 1) low awareness of CRDs; 2) limited data on CRD burden and treatments in LMICs; 3) ineffective procurement and distribution networks; and 4) poor communication of the needs of people with CRDs. Solutions discussed were 1) generation of data to inform policy and practice; 2) capacity building; 3) improved procurement mechanisms; 4) strengthened advocacy practices; and 5) a World Health Assembly Resolution.CONCLUSION: There are opportunities to achieve improved access to affordable, quality-assured inhaled medicines in LMICs through coordinated, multi-stakeholder, collaborative efforts.

Mechanistic modelling of Virchows triad to assess thrombogenicity and stroke risk in atrial fibrillation patients

Background

Atrial fibrillation (AF) is responsible for almost one third of all strokes, with the left atrial appendage (LAA) being the primary thromboembolic source due to localised stimulation of prothrombotic mechanisms; blood stasis, hypercoagulability and endothelial damage, known as Virchow's triad.

Aim

We propose an in-silico modelling pipeline that leverages clinical imaging data to mechanistically assess patient thrombogenicity for all aspects of Virchow's triad to improve the prediction and prevention of AF-related stroke.

Methods

Two AF patients undergoing Cine magnetic resonance imaging (sinus rhythm (SR) N=1 or AF N=1 during imaging) were selected for 3D left atrial (LA) modelling with patient-specific myocardial deformation prescribed from image-derived wall motion. Blood stasis was quantified by computational fluid dynamics (CFD) simulations of 5 cardiac cycles [1]. Generation of three key coagulation proteins; thrombin, fibrinogen and fibrin, were modelled to represent thrombus growth and hypercoagulability [2]. Regions prone to thrombogenesis by endothelial damage were identified by the oscillatory shear index (OSI), time averaged wall shear stress (TAWSS) and endothelial cell activation potential (ECAP) metrics in the LAA [3].

Results

Patient-specific LA simulations enabled the assessment of differences between SR and AF conditions, quantified as numerical characteristics of each aspect of Virchow's triad.

In SR, blood flow velocities were in the range 0–2.6 m/s with mean of 0.85 m/s in the LA cavity, while AF had a range between 0–1.6 m/s with mean of 0.55 m/s. The peak and mean LAA velocities in SR were 0.85 m/s and 0.14 m/s, while AF had a peak LAA velocity of 0.32 m/s and mean of 0.09 m/s, showing a 38% decrease during AF.

The thrombin concentration reached its steady state at 1.26 mmol/m3 in the AF case after 4.7 seconds, while thrombin was washed away from the initial injury site in SR. After 5 cardiac cycles of thrombus growth dynamics, the peak fibrin concentration in the LAA was 1.3 mmol/m3 in SR and 3.8 mmol/m3 in AF, with the thrombus area in AF being 40% larger. Fibrinogen concentration decreased at a rate equal to fibrin generation in both SR and AF solely in the area of thrombus formation.

ECAP in the LAA had peak values of 2.9 in SR and 3.7 in AF, with the location at highest risk of thrombogenesis above the LAA entrance. LAA OSI had an average value of 0.45 in AF versus 0.36 in SR, showing a 26% increase. Similarly, the TAWSS was 3.5x10–3 Pa on average over the LAA in AF compared to 1.4x10–3 Pa in SR.

Conclusions

Patient-specific LA models combining these three quantitative characteristics can be used to predict the higher thrombogenic risk in AF. After further validation, this novel approach for quantitative assessment of AF patient thrombogenicity based on modelling all factors in Virchow's triad can personalise and improve management of AF patients with a risk of stroke.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): UK Engineering and Physical Sciences Research Council

Observation of WWW Production in pp Collisions at sqrt[s]=13 TeV with the ATLAS Detector

This Letter reports the observation of WWW production and a measurement of its cross section using 139  fb^{-1} of proton-proton collision data recorded at a center-of-mass energy of 13 TeV by the ATLAS detector at the Large Hadron Collider. Events with two same-sign leptons (electrons or muons) and at least two jets, as well as events with three charged leptons, are selected. A multivariate technique is then used to discriminate between signal and background events. Events from WWW production are observed with a significance of 8.0 standard deviations, where the expectation is 5.4 standard deviations. The inclusive WWW production cross section is measured to be 820±100 (stat)±80 (syst)  fb, approximately 2.6 standard deviations from the predicted cross section of 511±18  fb calculated at next-to-leading-order QCD and leading-order electroweak accuracy.

A detailed map of Higgs boson interactions by the ATLAS experiment ten years after the discovery

The standard model of particle physics1-4 describes the known fundamental particles and forces that make up our Universe, with the exception of gravity. One of the central features of the standard model is a field that permeates all of space and interacts with fundamental particles5-9. The quantum excitation of this field, known as the Higgs field, manifests itself as the Higgs boson, the only fundamental particle with no spin. In 2012, a particle with properties consistent with the Higgs boson of the standard model was observed by the ATLAS and CMS experiments at the Large Hadron Collider at CERN10,11. Since then, more than 30 times as many Higgs bosons have been recorded by the ATLAS experiment, enabling much more precise measurements and new tests of the theory. Here, on the basis of this larger dataset, we combine an unprecedented number of production and decay processes of the Higgs boson to scrutinize its interactions with elementary particles. Interactions with gluons, photons, and W and Z bosons-the carriers of the strong, electromagnetic and weak forces-are studied in detail. Interactions with three third-generation matter particles (bottom (b) and top (t) quarks, and tau leptons (τ)) are well measured and indications of interactions with a second-generation particle (muons, μ) are emerging. These tests reveal that the Higgs boson discovered ten years ago is remarkably consistent with the predictions of the theory and provide stringent constraints on many models of new phenomena beyond the standard model.

AB0060 SYSTEMIC INFLAMMATORY EFFECT ON HIPPOCAMPAL VOLUME IN RHEUMATOID ARTHRITIS AND ULCERATIVE COLITIS

Background

Autoimmune diseases represent a large and heterogeneous group of disorders that afflict specific target organs. However, multiple factors point to common links between the differing presentations of autoimmune disorders.

With increased interest in further understanding the neuro-immune axis, autoimmune diseases represent an important opportunity to explore whether systemic inflammation from these autoimmune pathways has a central effect and, if so, whether there is a common or discrete central effect caused by different autoimmune diseases.

Objectives

The present study aimed to analyse hippocampal volume in patients with rheumatoid arthritis (RA) and ulcerative colitis (UC) as compared to healthy control groups. The hippocampus was chosen as a region of interest given the regulatory role it exhibits in the hypothalamic–pituitary–adrenal (HPA) axis2. Additionally, the hippocampus has been identified as a region that is affected in other autoimmune diseases such as systemic lupus erythematosus (SLE).

Methods

Data from 1,040 individuals in the UKBiobank Imaging sub-study were included in the present study. This was divided into two separate patient populations with separate control groups. Data from 267 individuals (mean age ± SD =65.52 ± 7.02, 70.8% females) were included in the RA patient group with 267 age and sex matched controls (mean age ± SD = 65.51 ± 7, 70.8% females). Data from 253 individuals (mean age ± SD = 64.09 ± 7.03, 51.6% females) were included in the UC patient group with 253 age and sex matched controls (mean age ± SD = 63.4 ± 7.02, 51.6% females).

The UKBiobank is a prospective observational study with a proposed cohort of 500,000 participants. The imaging substudy is planned to scan 100,000 of those participants with a standardised scanning protocol including MRI of the brain. Multi-modal images were acquired on a 3T scanner3. From the T1w data, volumetric imaging derived phenotypes (IDPs) are provided using the FMRIB Integrated Registration and Segmentation Tool (FIRST); http://fsl.fmrib.ox.ac.uk/fsl/fslwiki/FIRST. This study utilised the right and left hippocampal volume outputs from that tool.

Results

We observed a smaller hippocampal volume in UC patients when compared to healthy controls (difference right: 99.78 mm3, SD ± 38.97, p = 0.01; left: 74.30 mm3, SD ± 39.41, p = 0.06). The Cohen’s effect size was d = -0.24 [95% CI -0.43, -0.05] for right hippocampal volume and d = -0.18 [95% CI -0.36, 0.00] for left hippocampal volume.

Figure 1.

Right and left hippocampal volume in UC patients versus controls and right and left hippocampal volume in RA patients versus controls.

There was no significant difference seen in hippocampal volume in RA patients compared to controls (difference right: 61.32 mm3, SD ± 40.33, p = 0.13; left: 39.00 mm3, SD ± 38.19, p = 0.31). The Cohen’s effect size was d = -0.12 [95% CI -0.30, 0.06] for right hippocampal volume and d = -0.08 [95% CI -0.27, 0.10] for left hippocampal volume.

Conclusion

This study provides evidence of moderate reduction in hippocampal volumes in patients with ulcerative colitis as compared to age and sex matched healthy controls. This same effect was not seen in a similarly matched rheumatoid arthritis patient population. Further analysis of additional subcortical regions could provide further context for whether there are alternative regions affected in both RA and UC.

References

[1]Bellavance, M.A, Rivest, S., (2014), ‘The HPA – immune axis and the immunomodulatory actions of glucocorticoids in the brain’, Frontiers in Immunology, vol, 5, pp 136.

[2]Miller, K.L., Alfaro-Almagro, F., Bangerter, N.K. et al. (2016), ‘Multimodal Multimodal population brain imaging in the UK Biobank prospective epidemiological study’, Nature Neuroscience, vol. 19, pp. 1523-1536.

Disclosure of Interests

Jennifer Cox Grant/research support from: PhD funded by GlaxoSmithKline, Employee of: Former employee of GlaxoSmithKline, Marius de Groot Shareholder of: Employee of GlaxoSmithKline, Employee of: Employee of GlaxoSmithKline, James Cole: None declared, Steven Williams: None declared

Dynamic voltage attenuation identifies atrial fibrosis in a rabbit model: simultaneous assessment with optical mapping and contact electrogram mapping

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation. Academy of Medical Sciences.

Background

Bipolar voltage amplitude is a widely-used clinical parameter in atrial electrophysiology procedures. However, voltage amplitude is variable, and it has been shown that increasing activation rate decreases bipolar voltage amplitude in patients with atrial fibrillation. It is not known whether such voltage attenuation is a marker of the presence of atrial fibrosis which could therefore be used to improve intra-procedural assessment of atrial cardiomyopathy.

Purpose

We sought to investigate the effect of increasing activation rate on bipolar voltage amplitude in both healthy and fibrotic left atrial tissue.

Methods

10 New Zealand Rabbits were fed a high cholesterol diet (0.75%) for a period of 12 weeks to create an atrial fibrosis model. 10 Animals were fed normal chow. After terminal anaesthesia the heart was excised, and optical and voltage mapping of the excised left atrial tissue was performed. Blebbistatin was used to maintain cardiac stasis and the voltage sensitive dye RH237 was used for optical mapping. Voltage and optical recordings were made during pacing was from 3 different directions at rates from 2-6Hz and at 3 sites across the atrial tissue. Voltage amplitude was recorded as the mean amplitude over 10 beats during steady-state pacing. Optical recordings were used to measure conduction velocity and action potential characteristics. Only pacing runs showing 1:1 conduction were included in analysis. Atrial fibrosis was assessed using Masson’s Trichrome staining.

Results

The degree of atrial fibrosis was significantly greater in the atrial fibrosis model compared to healthy controls (15±3.24% vs. 9.74±4.98%, p=0.0069). Median voltage at base rate pacing of 2Hz was not significantly different between control and fibrotic atria (11.63mV, IQR 6.35mV vs. 10.3mV, IQR 6.81mV, p=0.71, respectively). Median voltage was significantly lower at 6Hz than at 2Hz in the control group (9.84mV, IQR 6.87mV, p=0.046). The degree of voltage attenuation between study groups was not significantly different between when pacing at 3hz or 4hz, whereas pacing at 5Hz and 6Hz showed significantly greater attenuation in fibrotic atria. At 5Hz the median reduction in amplitude from baseline in control vs fibrotic atria was 0.88mV, IQR 2.36mV vs 1.92mV, IQR 1.63mV (p=0.031). At 6 Hz the median reduction was 0.94mV, IQR 1.69mV vs 2.68mV, IQR 1.11mV, p=0.013 in control and fibrotic groups respectively.

Discussion

High cholesterol diet increased atrial fibrosis in a rabbit model. Bipolar voltage amplitude attenuation occurred in both control and fibrotic atria however the degree of voltage attenuation was significantly greater in fibrotic atria. These findings support the further evaluation of dynamic voltage attenuation for intraprocedural identification of atrial fibrosis.

Interpolation of electrophysiology parameters using OpenEP: technology development and clinical application

Funding Acknowledgements

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation

Background

Interpolation of data is common during clinical electrophysiology procedures. Applications include local activation mapping, voltage mapping and novel techniques including Sparkle and Coherence mapping. Nevertheless, underlying interpolation algorithms are proprietary and therefore challenging to reproduce. Importantly, direct comparison of electroanatomic datasets between system vendors is therefore not possible.

Purpose

We sought to (1) develop an open-source architecture for interpolation within the Open Electrophysiology Framework for Research (OpenEP; https://openep.io); (2) to provide three interpolation methods within this architecture and (3) to evaluate their performance against clinical data.

Method

The software architecture is shown in Figure 1A. The currently available methods are Radial Basis [1], Scattered Interpolant [2] and Local Smoothing [3]. Default parameters for each method are shown in Figure 1B.

The performance of each method was assessed using clinical left atrial mapping data, using the default options for each scheme. Following interpolation, a sample of 1000 activation/voltage points per mesh was used for analysis. For each interpolation method, correlation with clinical data was assessed using the intra-class correlation coefficient, whilst agreement was assessed using Bland Altman limits of agreement.

Results

For activation mapping, radial basis interpolation resulted in a smoother field than local smoothing, whilst scattered interpolation required more filtering of extreme values. Correlations between interpolated and original activation times were excellent for all interpolation schemes (radial basis R=0.91, p&lt;0.0001; local smoothing R=0.95, p&lt;0.0001; scattered interpolant R=0.92, p&lt;0.0001). Local smoothing resulted in the narrowest 95 percent limits of agreement (-19 to +20ms), compared to radial basis (-24 to +28ms) and scattered interpolation (-22 to +25ms).

For voltage mapping, the interpolation schemes resulted in similar appearances of low voltage areas, however correlations with clinical data were weaker than for activation mapping (radial basis R=0.84, p&lt;0.0001; local smoothing R=0.82, p&lt;0.0001; scattered interpolant R=0.79, p&lt;0.0001). The 95 percent limits of agreement were wide as a proportion of the mean data values, ranging from 83% (-0.8 to +0.66mV) for local smoothing to 97% (-0.78 to +0.63mV) for radial basis interpolation.

Conclusion

An extensible architecture is provided for data interpolation in OpenEP together with three interpolation methods. The methods performed wellfor local activation time interpolation but variation compared to clinical data was greater for voltage mapping. This new architecture will permit the optimisation of interpolation methods against "gold standard" simulation or histological data and facilitate comparison of datasets between system vendors.

Analysis of an adaptive lead weighted ResNet for multiclass classification of 12-lead ECGs

Background. Twelve lead ECGs are a core diagnostic tool for cardiovascular diseases. Here, we describe and analyse an ensemble deep neural network architecture to classify 24 cardiac abnormalities from 12 lead ECGs.Method. We proposed a squeeze and excite ResNet to automatically learn deep features from 12-lead ECGs, in order to identify 24 cardiac conditions. The deep features were augmented with age and gender features in the final fully connected layers. Output thresholds for each class were set using a constrained grid search. To determine why the model made incorrect predictions, two expert clinicians independently interpreted a random set of 100 misclassified ECGs concerning left axis deviation.Results. Using the bespoke weighted accuracy metric, we achieved a 5-fold cross-validation score of 0.684, and sensitivity and specificity of 0.758 and 0.969, respectively. We scored 0.520 on the full test data, and ranked 2nd out of 41 in the official challenge rankings. On a random set of misclassified ECGs, agreement between two clinicians and training labels was poor (clinician 1:κ= -0.057, clinician 2:κ= -0.159). In contrast, agreement between the clinicians was very high (κ= 0.92).Discussion. The proposed prediction model performed well on the validation and hidden test data in comparison to models trained on the same data. We also discovered considerable inconsistency in training labels, which is likely to hinder development of more accurate models.

Clinical presentation, disease course, and outcome of COVID-19 in hospitalized patients with and without pre-existing cardiac disease: a cohort study across 18 countries

AIMS

Patients with cardiac disease are considered high risk for poor outcomes following hospitalization with COVID-19. The primary aim of this study was to evaluate heterogeneity in associations between various heart disease subtypes and in-hospital mortality.

METHODS AND RESULTS

We used data from the CAPACITY-COVID registry and LEOSS study. Multivariable Poisson regression models were fitted to assess the association between different types of pre-existing heart disease and in-hospital mortality. A total of 16 511 patients with COVID-19 were included (21.1% aged 66-75 years; 40.2% female) and 31.5% had a history of heart disease. Patients with heart disease were older, predominantly male, and often had other comorbid conditions when compared with those without. Mortality was higher in patients with cardiac disease (29.7%; n = 1545 vs. 15.9%; n = 1797). However, following multivariable adjustment, this difference was not significant [adjusted risk ratio (aRR) 1.08, 95% confidence interval (CI) 1.02-1.15; P = 0.12 (corrected for multiple testing)]. Associations with in-hospital mortality by heart disease subtypes differed considerably, with the strongest association for heart failure (aRR 1.19, 95% CI 1.10-1.30; P < 0.018) particularly for severe (New York Heart Association class III/IV) heart failure (aRR 1.41, 95% CI 1.20-1.64; P < 0.018). None of the other heart disease subtypes, including ischaemic heart disease, remained significant after multivariable adjustment. Serious cardiac complications were diagnosed in <1% of patients.

CONCLUSION

Considerable heterogeneity exists in the strength of association between heart disease subtypes and in-hospital mortality. Of all patients with heart disease, those with heart failure are at greatest risk of death when hospitalized with COVID-19. Serious cardiac complications are rare during hospitalization.

A111 A RECTUM-SPECIFIC SELECTIVE RESECTION ALGORITHM OPTIMIZES ONCOLOGIC OUTCOMES FOR LARGE NON-PEDUNCULATED RECTAL POLYPS

Background

Endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD) are complementary techniques for large (≥ 20mm) non-pedunculated rectal polyps (LNPRPs). A mechanism for appropriate technique selection has not been described.

Aims

To evaluate whether a selective resection algorithm using EMR and ESD, based on real-time optical evaluation, optimizes oncologic outcomes for LNPRPs

Methods

We evaluated the performance of a selective resection algorithm (SRA; 08/2017-04/2021) compared to a universal EMR algorithm (UEA; 07/2008-07/2017) for LNPRPs within a prospective observational study. In the SRA, LNPRPs with features of superficial submucosal invasive cancer (SMIC < 1000μm; S-SMIC; Kudo pit pattern Vi), or with an increased risk of SMIC (Paris 0-Is or 0-IIa+Is non-granular, 0-IIa+Is granular with a dominant nodule ≥ 10mm) underwent ESD. The remaining LNPRPs underwent EMR. Algorithm performance was evaluated by SMIC identified after EMR, curative oncologic resection (R0 resection, S-SMIC, absence of negative histologic features), technical success, adverse events, and recurrence at first surveillance colonoscopy.

Results

480 LNPRPs were evaluated (290 UEA, 190 SRA). Median lesion size was 40mm (IQR 30-60mm). In the SRA, 103 (54.2%) and 87 (45.8%) LNPRPs underwent EMR and ESD, respectively. SMIC was identified in 56 (11.7%) LNPRPs. Significant differences in SMIC after EMR (SRA 1 (1.0%) vs. UEA 35 (12.1%); p = 0.001), curative oncologic resection (SRA 7 (33.3%) vs. UEA 2 (5.7%); p = 0.010), and recurrence (SRA 2 (1.6%) vs. UEA 40 (17.2%); p < 0.001) were identified. No significant differences in technical success or adverse events were identified (all p > 0.137). Among potentially curable malignant LNPRPs which underwent ESD, 100% (7/7) were cured.

Conclusions

A SRA optimizes oncologic outcomes for LNPRPs and mitigates the risk of piecemeal resection of cancers.

Funding Agencies

The Cancer Institute of New South Wales provided funding for a research nurse and data manager to assist with the administration of the study. Neal Shahidi was supported by the University of British Columbia Clinician Investigator Program. There was no influence from either institution regarding study design or conduct, data collection, management, analysis, interpretation, preparation, review, or approval of the manuscript.

Search for Lepton-Flavor Violation in Z-Boson Decays with τ Leptons with the ATLAS Detector

A search for lepton-flavor-violating Z→eτ and Z→μτ decays with pp collision data recorded by the ATLAS detector at the LHC is presented. This analysis uses 139  fb^{-1} of Run 2 pp collisions at sqrt[s]=13  TeV and is combined with the results of a similar ATLAS search in the final state in which the τ lepton decays hadronically, using the same data set as well as Run 1 data. The addition of leptonically decaying τ leptons significantly improves the sensitivity reach for Z→ℓτ decays. The Z→ℓτ branching fractions are constrained in this analysis to B(Z→eτ)<7.0×10^{-6} and B(Z→μτ)<7.2×10^{-6} at 95% confidence level. The combination with the previously published analyses sets the strongest constraints to date: B(Z→eτ)<5.0×10^{-6} and B(Z→μτ)<6.5×10^{-6} at 95% confidence level.