ORCID Profile
0000-0002-0948-5775
Current Organisations
Université Grenoble Alpes
,
CNRS en Alpes
,
Queensland University of Technology
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Publisher: IOP Publishing
Date: 04-04-2013
Publisher: Oxford University Press (OUP)
Date: 27-03-2023
Abstract: Sustainable investment in computerized decision support systems (CDSS) requires robust evaluation of their economic impacts compared with current clinical workflows. We reviewed current approaches used to evaluate the costs and consequences of CDSS in hospital settings and presented recommendations to improve the generalizability of future evaluations. A scoping review of peer-reviewed research articles published since 2010. Searches were completed in the PubMed, Ovid Medline, Embase, and Scopus databases (last searched February 14, 2023). All studies reported the costs and consequences of a CDSS-based intervention compared with current hospital workflows. Findings were summarized using narrative synthesis. In idual studies were further appraised against the Consolidated Health Economic Evaluation and Reporting (CHEERS) 2022 checklist. Twenty-nine studies published since 2010 were included. Studies evaluated CDSS for adverse event surveillance (5 studies), antimicrobial stewardship (4 studies), blood product management (8 studies), laboratory testing (7 studies), and medication safety (5 studies). All studies evaluated costs from a hospital perspective but varied based on the valuation of resources affected by CDSS implementation, and the measurement of consequences. We recommend future studies follow guidance from the CHEERS checklist use study designs that adjust for confounders consider both the costs of CDSS implementation and adherence evaluate consequences that are directly or indirectly affected by CDSS-initiated behavior change examine the impacts of uncertainty and differences in outcomes across patient subgroups. Improving consistency in the conduct and reporting of evaluations will enable detailed comparisons between promising initiatives, and their subsequent uptake by decision-makers.
Publisher: Oxford University Press (OUP)
Date: 25-03-2023
Abstract: Clinical prediction models providing binary categorizations for clinical decision support require the selection of a probability threshold, or “cutpoint,” to classify in iduals. Existing cutpoint selection approaches typically optimize test-specific metrics, including sensitivity and specificity, but overlook the consequences of correct or incorrect classification. We introduce a new cutpoint selection approach considering downstream consequences using net monetary benefit (NMB) and through simulations compared it with alternative approaches in 2 use-cases: (i) preventing intensive care unit readmission and (ii) preventing inpatient falls. Parameter estimates for costs and effectiveness from prior studies were included in Monte Carlo simulations. For each use-case, we simulated the expected NMB resulting from the model-guided decision using a range of cutpoint selection approaches, including our new value-optimizing approach. Sensitivity analyses applied alternative event rates, model discrimination, and calibration performance. The proposed approach that considered expected downstream consequences was frequently NMB-maximizing compared with other methods. Sensitivity analysis demonstrated that it was or closely tracked the optimal strategy under a range of scenarios. Under scenarios of relatively low event rates and discrimination that may be considered realistic for intensive care (prevalence = 0.025, area under the receiver operating characteristic curve [AUC] = 0.70) and falls (prevalence = 0.036, AUC = 0.70), our proposed cutpoint method was either the best or similar to the best of the compared methods regarding NMB, and was robust to model miscalibration. Our results highlight the potential value of conditioning cutpoints on the implementation setting, particularly for rare and costly events, which are often the target of prediction model development research. This study proposes a cutpoint selection method that may optimize clinical decision support systems toward value-based care.
Publisher: Springer Science and Business Media LLC
Date: 07-2021
DOI: 10.1038/S41567-021-01225-Z
Abstract: Leptons with essentially the same properties apart from their mass are grouped into three families (or flavours). The number of leptons of each flavour is conserved in interactions, but this is not imposed by fundamental principles. Since the formulation of the standard model of particle physics, the observation of flavour oscillations among neutrinos has shown that lepton flavour is not conserved in neutrino weak interactions. So far, there has been no experimental evidence that this also occurs in interactions between charged leptons. Such an observation would be a sign of undiscovered particles or a yet unknown type of interaction. Here the ATLAS experiment at the Large Hadron Collider at CERN reports a constraint on lepton-flavour-violating effects in weak interactions, searching for Z -boson decays into a τ lepton and another lepton of different flavour with opposite electric charge. The branching fractions for these decays are measured to be less than 8.1 × 10 −6 ( e τ ) and 9.5 × 10 −6 ( μ τ ) at the 95% confidence level using 139 fb −1 of proton–proton collision data at a centre-of-mass energy of $$\\sqrt{s}=13\\,{\\rm{TeV}}$$ s = 13 TeV and 20.3 fb −1 at $$\\sqrt{s}=8\\,{\\rm{TeV}}.$$ s = 8 TeV . These results supersede the limits from the Large Electron–Positron Collider experiments conducted more than two decades ago.
Publisher: Springer Science and Business Media LLC
Date: 05-2017
Publisher: American Physical Society (APS)
Date: 26-03-2021
Publisher: The Open Journal
Date: 05-04-2023
DOI: 10.21105/JOSS.05328
Publisher: Springer Science and Business Media LLC
Date: 02-2018
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Abstract: A measurement of four-top-quark production using proton-proton collision data at a centre-of-mass energy of 13 TeV collected by the ATLAS detector at the Large Hadron Collider corresponding to an integrated luminosity of 139 fb − 1 is presented. Events are selected if they contain a single lepton (electron or muon) or an opposite-sign lepton pair, in association with multiple jets. The events are categorised according to the number of jets and how likely these are to contain b -hadrons. A multivariate technique is then used to discriminate between signal and background events. The measured four-top-quark production cross section is found to be $$ {26}_{-15}^{+17} $$ 26 − 15 + 17 fb, with a corresponding observed (expected) significance of 1.9 (1.0) standard deviations over the background-only hypothesis. The result is combined with the previous measurement performed by the ATLAS Collaboration in the multilepton final state. The combined four-top-quark production cross section is measured to be $$ {24}_{-6}^{+7} $$ 24 − 6 + 7 fb, with a corresponding observed (expected) signal significance of 4.7 (2.6) standard deviations over the background-only predictions. It is consistent within 2.0 standard deviations with the Standard Model expectation of 12 . 0 ± 2 . 4 fb.
Publisher: Springer Science and Business Media LLC
Date: 03-2018
Publisher: American Physical Society (APS)
Date: 24-03-2021
Publisher: Elsevier BV
Date: 08-2018
Publisher: Elsevier BV
Date: 2014
Publisher: Springer Science and Business Media LLC
Date: 19-04-2021
Abstract: A search for new phenomena with top quark pairs in final states with one isolated electron or muon, multiple jets, and large missing transverse momentum is performed. Signal regions are designed to search for two-, three-, and four-body decays of the directly pair-produced supersymmetric partner of the top quark (stop). Additional signal regions are designed specifically to search for spin-0 mediators that are produced in association with a pair of top quarks and decay into a pair of dark-matter particles. The search is performed using the Large Hadron Collider proton-proton collision dataset at a centre-of-mass energy of $$ \\sqrt{s} $$ s = 13 TeV recorded by the ATLAS detector from 2015 to 2018, corresponding to an integrated luminosity of 139 fb − 1 . No significant excess above the Standard Model background is observed, and limits at 95% confidence level are set in the stop-neutralino mass plane and as a function of the mediator mass or the dark-matter particle mass. Stops are excluded up to 1200 GeV (710 GeV) in the two-body (three-body) decay scenario. In the four-body scenario stops up to 640 GeV are excluded for a stop-neutralino mass difference of 60 GeV. Scalar and pseudoscalar dark-matter mediators are excluded up to 200 GeV when the coupling strengths of the mediator to Standard Model and dark-matter particles are both equal to one and when the mass of the dark-matter particle is 1 GeV.
Publisher: American Physical Society (APS)
Date: 19-02-2021
Publisher: Elsevier BV
Date: 09-2022
DOI: 10.1016/J.JVAL.2022.01.017
Abstract: The EuroQoL 3-level version of EQ-5D and 5-level version of EQ-5D questionnaires are often used to quantify health states. They include ordinal responses across 5 health dimensions (EQ-5D index) and an EQ-visual analog scale (EQ-VAS) overall health rating. We investigated the value of incorporating the EQ-VAS to update health utility estimates using a Bayesian framework. We created a joint bivariate normal EQ-VAS and EQ-5D index utility model and compared this to a univariate normal EQ-5D index utility model. We tested these models for 1026 Sri Lankan patients with chronic kidney disease and 94 Australian patients with wounds. We validated our approach by simulating EQ-VAS and EQ-5D index responses and applying our Bayesian model and then comparing the modeled estimates to our observed data. The combined model showed a reduction in estimate uncertainty for all respondents. Compared with the EQ-5D index-only model, the mean utility for Sri Lankan respondents dropped from 0.556 (0.534-0.579) to 0.540 (0.521-0.559) in men and increased from 0.489 (0.461-0.518) to 0.528 (0.506-0.550) in women, with reduced credible interval width by 13% and 23%, respectively. The mean utility in Australian respondents moved from 0.715 (0.633-0.800) to 0.716 (0.652-0.782) in men, and 0.652 (0.581-0.723) to 0.652 (0.593-0.711) in women, with reduced credible interval width by 23% and 17%, respectively. The credible interval width for simulated data also narrowed, ranging from 8.3 to 8.5%. Including the EQ-VAS through Bayesian methods can add value by reducing requisite s le sizes and decision uncertainty using small amounts of additional data that is often collected but rarely used.
Publisher: IOP Publishing
Date: 19-05-2011
Publisher: Springer Science and Business Media LLC
Date: 02-2021
Abstract: A search for the supersymmetric partners of quarks and gluons (squarks and gluinos) in final states containing jets and missing transverse momentum, but no electrons or muons, is presented. The data used in this search were recorded by the ATLAS experiment in proton-proton collisions at a centre-of-mass energy of $$ \\sqrt{s} $$ s = 13 TeV during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb − 1 . The results are interpreted in the context of various R -parity-conserving models where squarks and gluinos are produced in pairs or in association and a neutralino is the lightest supersymmetric particle. An exclusion limit at the 95% confidence level on the mass of the gluino is set at 2.30 TeV for a simplified model containing only a gluino and the lightest neutralino, assuming the latter is massless. For a simplified model involving the strong production of mass-degenerate first- and second-generation squarks, squark masses below 1.85 TeV are excluded if the lightest neutralino is massless. These limits extend substantially beyond the region of supersymmetric parameter space excluded previously by similar searches with the ATLAS detector.
Publisher: American Physical Society (APS)
Date: 27-07-2021
Publisher: CSIRO Publishing
Date: 2018
DOI: 10.1071/AH17276
Abstract: Objective The HealthPathways program is an online information portal that helps clinicians provide consistent and integrated patient care within a local health system through localised pathways for diagnosis, treatment and management of various health conditions. These pathways are consistent with the definition of clinical pathways. Evaluations of HealthPathways programs have thus far focused primarily on website utilisation and clinical users’ experience and satisfaction, with limited evidence on changes to patient outcomes. This lack motivated a literature review of the effects of clinical pathways on patient and economic outcomes to inform a subsequent HealthPathways evaluation. Methods A systematic review was performed to summarise the analytical methods, study designs and results of studies evaluating clinical pathways with an economic outcome component published between 1 January 2000 and 31 August 2017 in four academic literature databases. Results Fifty-five relevant articles were identified for inclusion in this review. The practical pre-post study design with retrospective baseline data extraction and prospective intervention data collection was most commonly used in the evaluations identified. Straightforward statistical methods for comparing outcomes, such as the t-test or χ2 test, were frequently used. Only four of the 55 articles performed a cost-effectiveness analysis. Clinical pathways were generally associated with improved patient outcomes and positive economic outcomes in hospital settings. Conclusions Clinical pathways evaluations commonly use pragmatic study designs, straightforward statistical tests and cost–consequence analyses. More HealthPathways program evaluations focused on patient and economic outcomes, clinical pathway evaluations in a primary care setting and cost-effectiveness analyses of clinical pathways are needed. What is known about the topic? HealthPathways is a web-based program that originated from Canterbury, New Zealand, and has seen uptake elsewhere in New Zealand, Australia and the UK. The HealthPathways program aims to assist the provision of consistent and integrated health services through dedicated, localised pathways for various health conditions specific to the health region. Evaluations of HealthPathways program focused on patient and economic outcomes have been limited. What does this paper add? This review synthesises the academic literature of clinical pathways evaluations in order to inform a subsequent HealthPathways evaluation. The focus of the synthesis was on the analytical methods and study designs used in the previous evaluations. The previous clinical pathway evaluations have been pragmatic in nature with relatively straightforward study designs and analysis. What are the implications for practitioners? There is a need for more economic and patient outcome evaluations for HealthPathways programs. More sophisticated statistical analyses and economic evaluations could add value to these evaluations, where appropriate and taking into consideration the data limitations.
Publisher: Springer Science and Business Media LLC
Date: 02-2021
Abstract: A search for dark matter is conducted in final states containing a photon and missing transverse momentum in proton-proton collisions at $$ \\sqrt{s} $$ s = 13 TeV. The data, collected during 2015–2018 by the ATLAS experiment at the CERN LHC, correspond to an integrated luminosity of 139 fb − 1 . No deviations from the predictions of the Standard Model are observed and 95% confidence-level upper limits between 2.45 fb and 0.5 fb are set on the visible cross section for contributions from physics beyond the Standard Model, in different ranges of the missing transverse momentum. The results are interpreted as 95% confidence-level limits in models where weakly interacting dark-matter candidates are pair-produced via an s -channel axial-vector or vector mediator. Dark-matter candidates with masses up to 415 (580) GeV are excluded for axial-vector (vector) mediators, while the maximum excluded mass of the mediator is 1460 (1470) GeV. In addition, the results are expressed in terms of 95% confidence-level limits on the parameters of a model with an axion-like particle produced in association with a photon, and are used to constrain the coupling g a Z γ of an axion-like particle to the electroweak gauge bosons.
Publisher: IOP Publishing
Date: 07-2021
DOI: 10.1088/1748-0221/16/07/P07029
Abstract: The ATLAS experiment at the Large Hadron Collider (LHC) employs a trigger system consisting of a first-level hardware trigger (L1) and a software-based high-level trigger. The L1 muon trigger system selects muon candidates, assigns them to the correct LHC bunch crossing and classifies them into one of six transverse-momentum threshold classes. The L1 muon trigger system uses resistive-plate chambers (RPCs) to generate the muon-induced trigger signals in the central (barrel) region of the ATLAS detector. The ATLAS RPCs are arranged in six concentric layers and operate in a toroidal magnetic field with a bending power of 1.5 to 5.5 Tm. The RPC detector consists of about 3700 gas volumes with a total surface area of more than 4000 m 2 . This paper reports on the performance of the RPC detector and L1 muon barrel trigger using 60.8 fb -1 of proton-proton collision data recorded by the ATLAS experiment in 2018 at a centre-of-mass energy of 13 TeV. Detector and trigger performance are studied using Z boson decays into a muon pair. Measurements of the RPC detector response, efficiency, and time resolution are reported. Measurements of the L1 muon barrel trigger efficiencies and rates are presented, along with measurements of the properties of the selected s le of muon candidates. Measurements of the RPC currents, counting rates and mean avalanche charge are performed using zero-bias collisions. Finally, RPC detector response and efficiency are studied at different high voltage and front-end discriminator threshold settings in order to extrapolate detector response to the higher luminosity expected for the High Luminosity LHC.
Publisher: Springer Science and Business Media LLC
Date: 30-10-2021
Abstract: A search for pair production of third-generation scalar leptoquarks decaying into a top quark and a τ -lepton is presented. The search is based on a dataset of pp collisions at $$ \\sqrt{s} $$ s = 13 TeV recorded with the ATLAS detector during Run 2 of the Large Hadron Collider, corresponding to an integrated luminosity of 139 fb − 1 . Events are selected if they have one light lepton (electron or muon) and at least one hadronically decaying τ -lepton, or at least two light leptons. In addition, two or more jets, at least one of which must be identified as containing b -hadrons, are required. Six final states, defined by the multiplicity and flavour of lepton candidates, are considered in the analysis. Each of them is split into multiple event categories to simultaneously search for the signal and constrain several leading backgrounds. The signal-rich event categories require at least one hadronically decaying τ -lepton candidate and exploit the presence of energetic final-state objects, which is characteristic of signal events. No significant excess above the Standard Model expectation is observed in any of the considered event categories, and 95% CL upper limits are set on the production cross section as a function of the leptoquark mass, for different assumptions about the branching fractions into tτ and bν . Scalar leptoquarks decaying exclusively into tτ are excluded up to masses of 1 . 43 TeV while, for a branching fraction of 50% into tτ , the lower mass limit is 1 . 22 TeV.
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Abstract: A measurement of prompt photon-pair production in proton-proton collisions at $$ \\sqrt{s} $$ s = 13 TeV is presented. The data were recorded by the ATLAS detector at the LHC with an integrated luminosity of 139 fb − 1 . Events with two photons in the well-instrumented region of the detector are selected. The photons are required to be isolated and have a transverse momentum of $$ {p}_{\\mathrm{T}{,}_{\\gamma 1(2)}} $$ p T , γ 1 2 40 (30) GeV for the leading (sub-leading) photon. The differential cross sections as functions of several observables for the diphoton system are measured and compared with theoretical predictions from state-of-the-art Monte Carlo and fixed-order calculations. The QCD predictions from next-to-next-to-leading-order calculations and multi-leg merged calculations are able to describe the measured integrated and differential cross sections within uncertainties, whereas lower-order calculations show significant deviations, demonstrating that higher-order perturbative QCD corrections are crucial for this process. The resummed predictions with parton showers additionally provide an excellent description of the low transverse-momentum regime of the diphoton system.
Publisher: Ubiquity Press, Ltd.
Date: 2022
DOI: 10.5334/IJIC.5997
Publisher: Elsevier BV
Date: 08-2021
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Abstract: The production of dark matter in association with Higgs bosons is predicted in several extensions of the Standard Model. An exploration of such scenarios is presented, considering final states with missing transverse momentum and b -tagged jets consistent with a Higgs boson. The analysis uses proton-proton collision data at a centre-of-mass energy of 13 TeV recorded by the ATLAS experiment at the LHC during Run 2, amounting to an integrated luminosity of 139 fb − 1 . The analysis, when compared with previous searches, benefits from a larger dataset, but also has further improvements providing sensitivity to a wider spectrum of signal scenarios. These improvements include both an optimised event selection and advances in the object identification, such as the use of the likelihood-based significance of the missing transverse momentum and variable-radius track-jets. No significant deviation from Standard Model expectations is observed. Limits are set, at 95% confidence level, in two benchmark models with two Higgs doublets extended by either a heavy vector boson Z ′ or a pseudoscalar singlet a and which both provide a dark matter candidate χ . In the case of the two-Higgs-doublet model with an additional vector boson Z ′, the observed limits extend up to a Z ′ mass of 3 TeV for a mass of 100 GeV for the dark matter candidate. The two-Higgs-doublet model with a dark matter particle mass of 10 GeV and an additional pseudoscalar a is excluded for masses of the a up to 520 GeV and 240 GeV for tan β = 1 and tan β = 10 respectively. Limits on the visible cross-sections are set and range from to 0.05 fb to 3.26 fb, depending on the missing transverse momentum and b -quark jet multiplicity requirements.
Publisher: Springer Science and Business Media LLC
Date: 2021
Abstract: A measurement of event-shape variables in proton-proton collisions at large momentum transfer is presented using data collected at $$ \\sqrt{s} $$ s = 13 TeV with the ATLAS detector at the Large Hadron Collider. Six event-shape variables calculated using hadronic jets are studied in inclusive multijet events using data corresponding to an integrated luminosity of 139 fb − 1 . Measurements are performed in bins of jet multiplicity and in different ranges of the scalar sum of the transverse momenta of the two leading jets, reaching scales beyond 2 TeV. These measurements are compared with predictions from Monte Carlo event generators containing leading-order or next-to-leading order matrix elements matched to parton showers simulated to leading-logarithm accuracy. At low jet multiplicities, shape discrepancies between the measurements and the Monte Carlo predictions are observed. At high jet multiplicities, the shapes are better described but discrepancies in the normalisation are observed.
Publisher: Elsevier BV
Date: 11-2021
Publisher: BMJ
Date: 22-06-2022
DOI: 10.1136/BMJQS-2021-014527
Abstract: Hospital patients experiencing clinical deterioration are at greater risk of adverse events. Monitoring patients through early warning systems is widespread, despite limited published evidence that they improve patient outcomes. Current limitations including infrequent or incorrect risk calculations may be mitigated by integration into electronic medical records. Our objective was to examine the impact on patient outcomes of systems for detecting and responding to real-time, automated alerts for clinical deterioration. This review was conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews checklist. We searched Medline, CINAHL and Embase for articles implementing real-time, automated deterioration alerts in hospitalised adults evaluating one or more patient outcomes including intensive care unit admission, length of stay, in-hospital cardiopulmonary arrest and in-hospital death. Of 639 studies identified, 18 were included in this review. Most studies did not report statistically significant associations between alert implementation and better patient outcomes. Four studies reported statistically significant improvements in two or more patient outcomes, and were the only studies to directly involve the patient’s clinician. However, only one of these four studies was robust to existing trends in patient outcomes. Of the six studies using robust study designs, one reported a statistically significant improvement in patient outcomes the rest did not detect differences. Most studies in this review did not detect improvements in patient outcomes following the implementation of real-time deterioration alerts. Future implementation studies should consider: directly involving the patient’s physician or a dedicated surveillance nurse in structured response protocols for deteriorating patients the workflow of alert recipients and incorporating model features into the decision process to improve clinical utility.
Publisher: Elsevier BV
Date: 03-2012
Publisher: Springer Science and Business Media LLC
Date: 14-08-2017
DOI: 10.1038/NPHYS4208
Publisher: Springer Science and Business Media LLC
Date: 04-2021
Abstract: The results of a search for direct pair production of top squarks and for dark matter in events with two opposite-charge leptons (electrons or muons), jets and missing transverse momentum are reported, using 139 fb − 1 of integrated luminosity from proton-proton collisions at $$ \\sqrt{s} $$ s = 13 TeV, collected by the ATLAS detector at the Large Hadron Collider during Run 2 (2015–2018). This search considers the pair production of top squarks and is sensitive across a wide range of mass differences between the top squark and the lightest neutralino. Additionally, spin-0 mediator dark-matter models are considered, in which the mediator is produced in association with a pair of top quarks. The mediator subsequently decays to a pair of dark-matter particles. No significant excess of events is observed above the Standard Model background, and limits are set at 95% confidence level. The results exclude top squark masses up to about 1 TeV, and masses of the lightest neutralino up to about 500 GeV. Limits on dark-matter production are set for scalar (pseudoscalar) mediator masses up to about 250 (300) GeV.
Publisher: Springer Science and Business Media LLC
Date: 06-2021
DOI: 10.1140/EPJC/S10052-021-09192-8
Abstract: The paper presents a measurement of the Standard Model Higgs Boson decaying to b -quark pairs in the vector boson fusion (VBF) production mode. A s le corresponding to 126 $$\\hbox {fb}^{-1}$$ fb - 1 of $$\\sqrt{s} = 13\\,\\text {TeV}$$ s = 13 TeV proton–proton collision data, collected with the ATLAS experiment at the Large Hadron Collider, is analyzed utilizing an adversarial neural network for event classification. The signal strength, defined as the ratio of the measured signal yield to that predicted by the Standard Model for VBF Higgs production, is measured to be $$0.95^{+0.38}_{-0.36}$$ 0 . 95 - 0.36 + 0.38 , corresponding to an observed (expected) significance of 2.6 (2.8) standard deviations from the background only hypothesis. The results are additionally combined with an analysis of Higgs bosons decaying to b -quarks, produced via VBF in association with a photon.
Publisher: American Physical Society (APS)
Date: 26-07-2021
Publisher: Springer Science and Business Media LLC
Date: 05-2021
Abstract: The results of a search for new phenomena in final states with b -jets and missing transverse momentum using 139 fb − 1 of proton-proton data collected at a centre-of-mass energy $$ \\sqrt{s} $$ s = 13 TeV by the ATLAS detector at the LHC are reported. The analysis targets final states produced by the decay of a pair-produced supersymmetric bottom squark into a bottom quark and a stable neutralino. The analysis also seeks evidence for models of pair production of dark matter particles produced through the decay of a generic scalar or pseudoscalar mediator state in association with a pair of bottom quarks, and models of pair production of scalar third-generation down-type leptoquarks. No significant excess of events over the Standard Model background expectation is observed in any of the signal regions considered by the analysis. Bottom squark masses below 1270 GeV are excluded at 95% confidence level if the neutralino is massless. In the case of nearly mass-degenerate bottom squarks and neutralinos, the use of dedicated secondary-vertex identification techniques permits the exclusion of bottom squarks with masses up to 660 GeV for mass splittings between the squark and the neutralino of 10 GeV. These limits extend substantially beyond the regions of parameter space excluded by similar ATLAS searches performed previously.
Publisher: American Physical Society (APS)
Date: 10-06-2021
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Publisher: Springer Science and Business Media LLC
Date: 03-2021
Abstract: A search is presented for the production of the Standard Model Higgs boson in association with a high-energy photon. With a focus on the vector-boson fusion process and the dominant Higgs boson decay into b -quark pairs, the search benefits from a large reduction of multijet background compared to more inclusive searches. Results are reported from the analysis of 132 fb − 1 of pp collision data at $$ \\sqrt{s} $$ s = 13 TeV collected with the ATLAS detector at the LHC. The measured Higgs boson signal yield in this final-state signature is 1 . 3 ± 1 . 0 times the Standard Model prediction. The observed significance of the Higgs boson signal above the background is 1 . 3 standard deviations, compared to an expected significance of 1 . 0 standard deviations.
Publisher: Elsevier BV
Date: 03-2011
Publisher: Springer Science and Business Media LLC
Date: 02-2021
DOI: 10.1140/EPJC/S10052-020-08734-W
Abstract: Differential cross-section measurements are presented for the electroweak production of two jets in association with a Z boson. These measurements are sensitive to the vector-boson fusion production mechanism and provide a fundamental test of the gauge structure of the Standard Model. The analysis is performed using proton–proton collision data collected by ATLAS at $$\\sqrt{s}=13\\ \\hbox {TeV}$$ s = 13 TeV and with an integrated luminosity of $$139\\ \\hbox {fb}^{-1}$$ 139 fb - 1 . The differential cross-sections are measured in the $$Z\\rightarrow \\ell ^+\\ell ^-$$ Z → ℓ + ℓ - decay channel ( $$\\ell =e,\\mu $$ ℓ = e , μ ) as a function of four observables: the dijet invariant mass, the rapidity interval spanned by the two jets, the signed azimuthal angle between the two jets, and the transverse momentum of the dilepton pair. The data are corrected for the effects of detector inefficiency and resolution and are sufficiently precise to distinguish between different state-of-the-art theoretical predictions calculated using Powheg+Pythia8 , Herwig7+Vbfnlo and Sherpa 2.2. The differential cross-sections are used to search for anomalous weak-boson self-interactions using a dimension-six effective field theory. The measurement of the signed azimuthal angle between the two jets is found to be particularly sensitive to the interference between the Standard Model and dimension-six scattering litudes and provides a direct test of charge-conjugation and parity invariance in the weak-boson self-interactions.
Publisher: Springer Science and Business Media LLC
Date: 11-2017
Publisher: Elsevier BV
Date: 09-2005
Publisher: Elsevier BV
Date: 12-2006
Publisher: American Physical Society (APS)
Date: 07-06-2021
Publisher: Springer Science and Business Media LLC
Date: 08-2021
DOI: 10.1140/EPJC/S10052-021-09402-3
Abstract: Jet energy scale and resolution measurements with their associated uncertainties are reported for jets using 36–81 fb $$^{-1}$$ - 1 of proton–proton collision data with a centre-of-mass energy of $$\sqrt{s}=13$$ s = 13 $${\text {Te}}{\text {V}}$$ TeV collected by the ATLAS detector at the LHC. Jets are reconstructed using two different input types: topo-clusters formed from energy deposits in calorimeter cells, as well as an algorithmic combination of charged-particle tracks with those topo-clusters, referred to as the ATLAS particle-flow reconstruction method. The anti- $$k_t$$ k t jet algorithm with radius parameter $$R=0.4$$ R = 0.4 is the primary jet definition used for both jet types. This result presents new jet energy scale and resolution measurements in the high pile-up conditions of late LHC Run 2 as well as a full calibration of particle-flow jets in ATLAS. Jets are initially calibrated using a sequence of simulation-based corrections. Next, several in situ techniques are employed to correct for differences between data and simulation and to measure the resolution of jets. The systematic uncertainties in the jet energy scale for central jets ( $$|\eta | .2$$ | η | 1.2 ) vary from 1% for a wide range of high- $$p_{{\text {T}}}$$ p T jets ( $$250 _{{\text {T}}} ~{\text {Ge}}{\text {V}}$$ 250 p T 2000 GeV ), to 5% at very low $$p_{{\text {T}}}$$ p T ( $$20~{\text {Ge}}{\text {V}}$$ 20 GeV ) and 3.5% at very high $$p_{{\text {T}}}$$ p T ( $$ .5~{\text {Te}}{\text {V}}$$ 2.5 TeV ). The relative jet energy resolution is measured and ranges from ( $$24 \pm 1.5$$ 24 ± 1.5 )% at 20 $${\text {Ge}}{\text {V}}$$ GeV to ( $$6 \pm 0.5$$ 6 ± 0.5 )% at 300 $${\text {Ge}}{\text {V}}$$ GeV .
Publisher: Elsevier BV
Date: 06-2020
Publisher: Elsevier BV
Date: 11-2017
Publisher: Elsevier BV
Date: 06-2018
Publisher: Springer Science and Business Media LLC
Date: 06-2021
Abstract: A search for charged Higgs bosons decaying into a top quark and a bottom quark is presented. The data analysed correspond to 139 fb − 1 of proton-proton collisions at $$ \\sqrt{s} $$ s = 13 TeV, recorded with the ATLAS detector at the LHC. The production of a heavy charged Higgs boson in association with a top quark and a bottom quark, pp → tbH + → tbtb , is explored in the H + mass range from 200 to 2000 GeV using final states with jets and one electron or muon. Events are categorised according to the multiplicity of jets and b -tagged jets, and multivariate analysis techniques are used to discriminate between signal and background events. No significant excess above the background-only hypothesis is observed and exclusion limits are derived for the production cross-section times branching ratio of a charged Higgs boson as a function of its mass they range from 3.6 pb at 200 GeV to 0.036 pb at 2000 GeV at 95% confidence level. The results are interpreted in the hMSSM and $$ {M}_h^{125} $$ M h 125 scenarios.
Publisher: Elsevier BV
Date: 09-2018
Publisher: Elsevier BV
Date: 05-2015
Publisher: Elsevier BV
Date: 05-2021
Publisher: Elsevier BV
Date: 09-2012
Publisher: Oxford University Press (OUP)
Date: 12-07-2019
Abstract: falls, seizures, syncope and transient ischaemic attacks (TIA) are common presentations to emergency departments sharing overlapping clinical features and diagnostic uncertainties. These transient attacks can be markers of serious adverse outcomes and are associated with high admission rates. We evaluated the effects of an integrated suite of pathways for transient attacks designed to improve adherence to best practices and reduce costs through fewer admissions. a suite of clinician-designed pathways based on initial presenting diagnosis was developed to support ambulant care in a large hospital in Queensland, Australia. We performed a set of regression analyses to identify the differences in total cost and length of stay (LOS) before and after implementation. We conducted a Monte Carlo simulation to estimate the cost savings of the freed capacity in the patient cohort. pathway implementation was associated with reduced admitted LOS and costs. Falls patients admitted LOS declined by 32.5%, and admission costs by 19.5%. Syncope, seizure, and TIA patients admitted LOS declined by 22% with no change in admitted costs. Despite a small increase in 90-day representations, total emergency department LOS was unchanged. Emergency department costs were similar between falls and non-falls patients. The Monte Carlo analysis showed that the most likely outcome was a cost savings in freed capacity of $71 per patient episode. the ATAP suite of pathways was associated with reduction in LOS, release of capacity and reduction in costs. Further study is needed to evaluate mechanisms and clinical outcomes in this vulnerable population.
Publisher: S. Karger AG
Date: 17-08-2022
DOI: 10.1159/000525727
Abstract: b i Introduction: /i /b The digitization of hospital systems, including integrated electronic medical records, has provided opportunities to improve the prediction performance of inpatient fall risk models and their application to computerized clinical decision support systems. This review describes the data sources and scope of methods reported in studies that developed inpatient fall prediction models, including machine learning and more traditional approaches to inpatient fall risk prediction. b i Methods: /i /b This scoping review used methods recommended by the Arksey and O’Malley framework and its recent advances. PubMed, CINAHL, IEEE Xplore, and EMBASE databases were systematically searched. Studies reporting the development of inpatient fall risk prediction approaches were included. There was no restriction on language or recency. Reference lists and manual searches were also completed. Reporting quality was assessed using adherence to Transparent Reporting of a multivariable prediction model for In idual Prognosis or Diagnosis statement (TRIPOD), where appropriate. b i Results: /i /b Database searches identified 1,396 studies, 63 were included for scoping assessment and 45 for reporting quality assessment. There was considerable overlap in data sources and methods used for model development. Fall prediction models typically relied on features from patient assessments, including indicators of physical function or impairment, or cognitive function or impairment. All but two studies used patient information at or soon after admission and predicted fall risk over the entire admission, without consideration of post-admission interventions, acuity changes or length of stay. Overall, reporting quality was poor, but improved in the past decade. b i Conclusion: /i /b There was substantial homogeneity in data sources and prediction model development methods. Use of artificial intelligence, including machine learning with high-dimensional data, remains underexplored in the context of hospital falls. Future research should consider approaches with the potential to utilize high-dimensional data from digital hospital systems, which may contribute to greater performance and clinical usefulness.
Publisher: American Physical Society (APS)
Date: 12-07-2021
Publisher: American Physical Society (APS)
Date: 31-08-2021
Publisher: Elsevier BV
Date: 10-2013
Publisher: SAGE Publications
Date: 2021
DOI: 10.1177/21501327211041489
Abstract: HealthPathways is a clinical information portal developed in New Zealand that enables general practitioners to manage and refer their patients in a local context. We analyzed specialist outpatient appointment costs in Mackay, Queensland before and after HealthPathways implementation. We retrospectively examined specialist outpatient costs for patients referred by Mackay general practitioners for conditions with varying levels of HealthPathways implementation. Ranked from most clinical pathways available to none, chronic diabetes, cardiology, respiratory, and urology visits from January to March 2015, pre-pathways, and January to March 2017, post-pathways, were assessed. Monte Carlo simulation was used to estimate cost changes. Per-visit costs were multiplied by visit numbers to estimate policy impact. The mean cost per visit increased from $220 to $305 for diabetes and $270 to $323 for respiratory, and decreased from $296 to $257 for cardiology and $444 to $293 for urology. The policy impact for each disease group over 3 months after accounting for visit numbers was a likely saving of $30 360 for diabetes and $10 270 for cardiology, and a likely cost increase of $24 449 for respiratory and $20 536 for urology. We observed that conditions with more comprehensive clinical pathways cost Mackay HHS substantially less following implementation. Costs for low and no pathway implementation referrals increased slightly over the same period.
Publisher: Springer Science and Business Media LLC
Date: 02-2021
DOI: 10.1140/EPJC/S10052-020-08677-2
Abstract: Measurements of the Standard Model Higgs boson decaying into a $$b\\bar{b}$$ b b ¯ pair and produced in association with a W or Z boson decaying into leptons, using proton–proton collision data collected between 2015 and 2018 by the ATLAS detector, are presented. The measurements use collisions produced by the Large Hadron Collider at a centre-of-mass energy of $$\\sqrt{s} = 13\\,\\text {Te}\\text {V}$$ s = 13 Te , corresponding to an integrated luminosity of $$139\\,\\mathrm {fb}^{-1}$$ 139 fb - 1 . The production of a Higgs boson in association with a W or Z boson is established with observed (expected) significances of 4.0 (4.1) and 5.3 (5.1) standard deviations, respectively. Cross-sections of associated production of a Higgs boson decaying into bottom quark pairs with an electroweak gauge boson, W or Z , decaying into leptons are measured as a function of the gauge boson transverse momentum in kinematic fiducial volumes. The cross-section measurements are all consistent with the Standard Model expectations, and the total uncertainties vary from 30% in the high gauge boson transverse momentum regions to 85% in the low regions. Limits are subsequently set on the parameters of an effective Lagrangian sensitive to modifications of the WH and ZH processes as well as the Higgs boson decay into $$b\\bar{b}$$ b b ¯ .
Publisher: BMJ
Date: 12-2021
DOI: 10.1136/BMJOPEN-2021-050070
Abstract: Epilepsy places a large burden on health systems, with hospitalisations for seizures alone occurring more frequently than those related to diabetes. However, the cost of epilepsy to the Australian health system is not well understood. The primary aim of this study is to quantify the health service use and cost of epilepsy in Queensland, Australia. Secondary aims are to identify differences in health service use and cost across population and disease subgroups, and to explore the associations between health service use and common comorbidities. This project will use data linkage to identify the health service utilisation and costs associated with epilepsy. A base cohort of patients will be identified from the Queensland Hospital Admitted Patient Data Collection. We will select all patients admitted between 2014 and 2018 with a diagnosis classification related to epilepsy. Two comparison cohorts will also be identified. Retrospective hospital admissions data will be linked with emergency department presentations, clinical costing data, specialist outpatient and allied health occasions of service data and mortality data. The level of health service use in Queensland, and costs associated with this, will be quantified using descriptive statistics. Difference in health service costs between groups will be explored using logistic regression. Linear regression will be used to model the associations of interest. The analysis will adjust for confounders including age, sex, comorbidities, indigenous status, and remoteness. Ethical approval has been obtained through the QUT University Human Research Ethics Committee (1900000333). Permission to waive consent has been granted under the Public Health Act 2005, with approval provided by all relevant data custodians. Findings of the proposed research will be communicated through presentations at national and international conferences, presentations to key stakeholders and decision-makers, and publications in international peer-reviewed journals.
Publisher: Elsevier BV
Date: 10-2016
Publisher: Springer Science and Business Media LLC
Date: 02-2017
Publisher: Springer Science and Business Media LLC
Date: 03-2018
Publisher: Springer Science and Business Media LLC
Date: 07-2021
DOI: 10.1038/S41567-021-01236-W
Abstract: The standard model of particle physics encapsulates our best current understanding of physics at the smallest scales. A fundamental axiom of this theory is the universality of the couplings of the different generations of leptons to the electroweak gauge bosons. The measurement of the ratio of the decay rate of W bosons to τ leptons and muons, R ( τ / μ ), constitutes an important test of this axiom. Using 139 fb −1 of proton–proton collisions recorded with the ATLAS detector at a centre-of-mass energy of 13 TeV, we report a measurement of this quantity from di-leptonic $$t\\overline{t}$$ t t ¯ events where the top quarks decay into a W boson and a bottom quark. We can distinguish muons originating from W bosons and those originating from an intermediate τ lepton through the muon transverse impact parameter and differences in the muon transverse momentum spectra. The measured value of R ( τ / μ ) is 0.992 ± 0.013 [± 0.007(stat) ± 0.011(syst)] and is in agreement with the hypothesis of universal lepton couplings as postulated in the standard model. This is the only such measurement from the Large Hadron Collider, so far, and obtains twice the precision of previous measurements.
Publisher: American Physical Society (APS)
Date: 10-2021
Publisher: Springer Science and Business Media LLC
Date: 03-2021
DOI: 10.1140/EPJC/S10052-021-08929-9
Abstract: A search for the pair production of heavy leptons as predicted by the type-III seesaw mechanism is presented. The search uses proton–proton collision data at a centre-of-mass energy of 13 TeV, corresponding to $$ 139\\,{\\text {fb}}^{-1} $$ 139 fb - 1 of integrated luminosity recorded by the ATLAS detector during Run 2 of the Large Hadron Collider. The analysis focuses on the final state with two light leptons (electrons or muons) of different flavour and charge combinations, with at least two jets and large missing transverse momentum. No significant excess over the Standard Model expectation is observed. The results are translated into exclusion limits on heavy-lepton masses, and the observed lower limit on the mass of the type-III seesaw heavy leptons is 790 GeV at 95% confidence level.
Publisher: American Physical Society (APS)
Date: 28-12-2021
Publisher: Springer Science and Business Media LLC
Date: 11-2021
Abstract: A novel search for exotic decays of the Higgs boson into pairs of long-lived neutral particles, each decaying into a bottom quark pair, is performed using 139 fb − 1 of $$ \\sqrt{s} $$ s = 13 TeV proton-proton collision data collected with the ATLAS detector at the LHC. Events consistent with the production of a Higgs boson in association with a leptonically decaying Z boson are analysed. Long-lived particle (LLP) decays are reconstructed from inner-detector tracks as displaced vertices with high mass and track multiplicity relative to Standard Model processes. The analysis selection requires the presence of at least two displaced vertices, effectively suppressing Standard Model backgrounds. The residual background contribution is estimated using a data-driven technique. No excess over Standard Model predictions is observed, and upper limits are set on the branching ratio of the Higgs boson to LLPs. Branching ratios above 10% are excluded at 95% confidence level for LLP mean proper lifetimes cτ as small as 4 mm and as large as 100 mm. For LLP masses below 40 GeV, these results represent the most stringent constraint in this lifetime regime.
Publisher: Elsevier BV
Date: 2022
Publisher: Springer Science and Business Media LLC
Date: 07-2021
Abstract: Measurements of four-lepton differential and integrated fiducial cross-sections in events with two same-flavour, opposite-charge electron or muon pairs are presented. The data correspond to 139 fb − 1 of $$ \\sqrt{s} $$ s = 13 TeV proton-proton collisions, collected by the ATLAS detector during Run 2 of the Large Hadron Collider (2015–2018). The final state has contributions from a number of interesting Standard Model processes that dominate in different four-lepton invariant mass regions, including single Z boson production, Higgs boson production and on-shell ZZ production, with a complex mix of interference terms, and possible contributions from physics beyond the Standard Model. The differential cross-sections include the four-lepton invariant mass inclusively, in slices of other kinematic variables, and in different lepton flavour categories. Also measured are dilepton invariant masses, transverse momenta, and angular correlation variables, in four regions of four-lepton invariant mass, each dominated by different processes. The measurements are corrected for detector effects and are compared with state-of-the-art Standard Model calculations, which are found to be consistent with the data. The Z → 4 ℓ branching fraction is extracted, giving a value of (4 . 41 ± 0 . 30) × 10 − 6 . Constraints on effective field theory parameters and a model based on a spontaneously broken B − L gauge symmetry are also evaluated. Further reinterpretations can be performed with the provided information.
Publisher: MDPI AG
Date: 09-09-2021
Abstract: When graduates of Australian social work courses embark on a career in mental health, the systems they enter are complex, fragmented and evolving. Emerging practitioners will commonly be confronted by the loneliness, social exclusion, poverty and prejudice experienced by people living with mental distress however, social work practice may not be focused on these factors. Instead, in accordance with the dominant biomedical perspective, symptom and risk management may predominate. Frustration with the limitations evident in this approach has seen the United Nations call for the transformation of mental health service delivery. Recognising paradigmatic influences on mental health social work may lead to a more considered enactment of person centred, recovery and rights-based approaches. This paper compares and contrasts influences of neo-liberalism, critical theory, human rights and post-structuralism on mental health social work practice. In preparing social work practitioners to recognise the influence of, and work more creatively with, intersecting paradigms, social work educators strive to foster a transformative approach to mental health practice that straddles discourses.
Publisher: Ubiquity Press, Ltd.
Date: 2022
DOI: 10.5334/IJIC.6980
Publisher: Springer Science and Business Media LLC
Date: 16-06-2022
DOI: 10.1038/S41598-022-14226-6
Abstract: We examined systems-level costs before and after the implementation of an emergency department paediatric sepsis screening, recognition and treatment pathway. Aggregated hospital admissions for all children aged 18y with a diagnosis code of sepsis upon admission in Queensland, Australia were compared for 16 participating and 32 non-participating hospitals before and after pathway implementation. Monte Carlo simulation was used to generate uncertainty intervals. Policy impacts were estimated using difference-in-difference analysis comparing observed and expected results. We compared 1055 patient episodes before (77.6% in-pathway) and 1504 after (80.5% in-pathway) implementation. Reductions were likely for non-intensive length of stay (− 20.8 h [− 36.1, − 8.0]) but not intensive care (–9.4 h [− 24.4, 5.0]). Non-pathway utilisation was likely unchanged for interhospital transfers (+ 3.2% [− 5.0%, 11.4%]), non-intensive (− 4.5 h [− 19.0, 9.8]) and intensive (+ 7.7 h, [− 20.9, 37.7]) care length of stay. After difference-in-difference adjustment, estimated savings were 596 [277, 942] non-intensive and 172 [148, 222] intensive care days. The program was cost-saving in 63.4% of simulations, with a mean value of $97,019 [− $857,273, $1,654,925] over 24 months. A paediatric sepsis pathway in Queensland emergency departments was associated with potential reductions in hospital utilisation and costs.
Publisher: Elsevier BV
Date: 02-2023
Publisher: Springer Science and Business Media LLC
Date: 11-2017
Publisher: Elsevier BV
Date: 05-2021
Location: United States of America
No related grants have been discovered for Fairouz Malek.