David Lawrence
A5013412137- Particle physics theoretical and experimental studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Nuclear physics research studies
- Particle Detector Development and Performance
- Radiation Detection and Scintillator Technologies
- Distributed and Parallel Computing Systems
- Atomic and Subatomic Physics Research
- Neutrino Physics Research
- Advanced Data Storage Technologies
- Dark Matter and Cosmic Phenomena
- Astrophysics and Cosmic Phenomena
- Scientific Computing and Data Management
- Nuclear Physics and Applications
- Medical Imaging Techniques and Applications
- Time Series Analysis and Forecasting
- Cardiac Ischemia and Reperfusion
- Quantum, superfluid, helium dynamics
- Cardiac Valve Diseases and Treatments
- Advanced NMR Techniques and Applications
- Cardiac Imaging and Diagnostics
- Pacific and Southeast Asian Studies
- Atomic and Molecular Physics
- Parallel Computing and Optimization Techniques
- Cancer Genomics and Diagnostics
University College London
2012-2025
Duke University
2000-2025
University College Hospital
2017-2025
Thomas Jefferson National Accelerator Facility
2014-2024
Saudi Aramco (Saudi Arabia)
2024
Old Dominion University
2020-2023
Catholic University of America
2023
University of America
2023
Pfizer (United States)
2008-2023
Ruhr University Bochum
2023
This paper introduces SC2LE (StarCraft II Learning Environment), a reinforcement learning environment based on the StarCraft game. domain poses new grand challenge for learning, representing more difficult class of problems than considered in most prior work. It is multi-agent problem with multiple players interacting; there imperfect information due to partially observed map; it has large action space involving selection and control hundreds units; state that must be solely from raw input...
<h3>Objectives</h3> Remote ischaemic preconditioning (RIPC), using brief cycles of limb ischaemia/reperfusion, is a non-invasive, low-cost intervention that may reduce perioperative myocardial injury (PMI) in patients undergoing cardiac surgery. We investigated whether RIPC can also improve short-term clinical outcomes. <h3>Methods</h3> One hundred and eighty elective coronary artery bypass graft (CABG) surgery and/or valve were randomised to receive either (2–5 min simultaneous upper arm...
We report on the measurement of γp→J/ψp cross section from E_{γ}=11.8 GeV down to threshold at 8.2 using a tagged photon beam with GlueX experiment. find that total falls toward less steeply than expected two-gluon exchange models. The differential dσ/dt has an exponential slope 1.67±0.39 GeV^{-2} 10.7 average energy. LHCb pentaquark candidates P_{c}^{+} can be produced in s channel this reaction. see no evidence for them and set model-dependent upper limits their branching fractions...
The ${\overline{\ensuremath{\nu}}}_{e}$ flux and spectrum have been measured at a distance of about 800 m from the reactors Palo Verde Nuclear Generating Station using segmented Gd-loaded liquid scintillator detector. Correlated positron-neutron events reaction ${\overline{\ensuremath{\nu}}}_{e}\stackrel{\ensuremath{\rightarrow}}{p}{e}^{+}n$ were recorded for period 200 d including 55 with one three off refueling. Backgrounds accounted by making use reactor-on reactor-off cycles, also novel...
The analysis and results are presented from the complete data set recorded at Palo Verde between September 1998 July 2000. In experiment, ${\overline{\ensuremath{\nu}}}_{\mathrm{e}}$ interaction rate has been measured a distance of 750 890 m reactors Nuclear Generating Station for total 350 days, including 108 days with one three off refueling. Backgrounds were determined by (a) $\mathrm{swap}$ technique based on difference signal background under reversal positron neutron parts correlated...
We report the first results of beam-spin asymmetry measured in reaction $\stackrel{\ensuremath{\rightarrow}}{e}p\ensuremath{\rightarrow}\mathrm{ep}\ensuremath{\gamma}$ at a beam energy 4.25 GeV. A large with $\mathrm{sin}\ensuremath{\varphi}$ modulation is observed, as predicted for interference term deeply virtual compton scattering (DVCS) and Bethe-Heitler process. The amplitude this...
We report on the initial results from a measurement of antineutrino flux and spectrum at distance about 800 m three reactors Palo Verde Nuclear Generating Station using segmented gadolinium-loaded scintillation detector. find that agrees with predicted in absence oscillations excluding 90% C.L. nu;(e)-nu;(x) Deltam(2)>1.12x10(-3) eV(2) for maximal mixing sin (2)2straight theta>0.21 large Deltam(2). Our support conclusion atmospheric neutrino observed by Super-Kamiokande do not involve nu(e).
Models of baryon structure predict a small quadrupole deformation the nucleon due to residual tensor forces between quarks or distortions from pion cloud. Sensitivity quark versus degrees freedom occurs through Q2 dependence magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in gamma*p-->Delta(+)-->p pi(0) transition. We report new experimental values for ratios E(1+)/M(1+) S(1+)/M(1+) over range = 0.4-1.8 GeV2, extracted precision p(e,e(')p)pi(0) data using truncated multipole...
Purpose To develop and validate equilibrium contrast material–enhanced computed tomography (CT) to measure myocardial extracellular volume (ECV) fraction by using a histologic reference standard compare CT with contrast-enhanced magnetic resonance (MR) imaging. Materials Methods A local ethics committee approved the study, all subjects gave fully informed written consent. An protocol was developed iohexol at 300 mg of iodine per milliliter (bolus 1 kilogram body weight administered rate 3...
To develop and validate equilibrium contrast material-enhanced computed tomography (CT) to measure myocardial extracellular volume (ECV) fraction by using a histologic reference standard compare CT with contrast-enhanced magnetic resonance (MR) imaging.A local ethics committee approved the study, all subjects gave fully informed written consent. An protocol was developed iohexol at 300 mg of iodine per milliliter (bolus 1 kilogram body weight administered rate 3 mL/sec, followed immediately...
Lineage tracing approaches have provided new insights into the cellular mechanisms that support tissue homeostasis in mice. However, relevance of these discoveries to human epithelial and its alterations disease is unknown. By developing a novel quantitative approach for analysis somatic mitochondrial mutations are accumulated over time, we demonstrate upper airway epithelium maintained by an equipotent basal progenitor cell population, which chance loss cells due lineage commitment...
Empyema is an increasingly frequent clinical problem worldwide, and has substantial morbidity mortality. Our objectives were to identify the clinical, surgical microbiological features, management outcomes, of empyema.A retrospective observational study over 12 years (1999-2010) was carried out at The Heart Hospital, London, United Kingdom. Patients with empyema identified by screening hospital electronic 'Clinical Data Repository'. Demographics, characteristics, underlying risk factors,...
Recent technical innovations and significant cost reductions have sharply increased the potential for using Membrane Bioreactor (MBR) technology in municipal wastewater treatment. MBR displays several advantages compared to traditional activated sludge processes, such as high effluent quality, limited space requirement with possibility of a flexible phased extension existing waste water treatment plants.Membrane Bioreactors Municipal Wastewater Treatment describes results comparative...
BACKGROUND. Epicardial adipose tissue (EAT) directly overlies the myocardium, with changes in its morphology and volume associated myriad cardiovascular metabolic diseases. However, EAT's immune structure cellular characterization remain incompletely described. We aimed to define phenotype of EAT humans compare such profiles across lean, obese, diabetic patients.
We report the total and differential cross sections for $J/\psi$ photoproduction with large acceptance GlueX spectrometer photon beam energies from threshold at 8.2~GeV up to 11.44~GeV over full kinematic range of momentum transfer squared, $t$. Such coverage facilitates extrapolation forward ($t = 0$) point beyond physical region. The section is used by many theoretical models plays an important role in understanding its relation $J/\psi-$proton interaction. These measurements near are also...
VERTIS CV was a randomised, double-blind, placebo-controlled, parallel-group, multicentre cardiovascular outcomes trial that evaluated the efficacy and safety of ertugliflozin in adults with type 2 diabetes atherosclerotic disease. The primary objective to show non-inferiority placebo respect outcome, major adverse events (a composite death from causes, non-fatal myocardial infarction, or stroke). analyses reported here aimed assess cardiorenal outcomes, kidney function, other older disease...
We have measured the spin structure functions g2p and g2d virtual photon asymmetries A2p A2d over kinematic range 0.02⩽x⩽0.8 0.7⩽Q2⩽20GeV2 by scattering 29.1 32.3 GeV longitudinally polarized electrons from transversely NH3 6LiD targets. Our g2 approximately follows twist-2 Wandzura–Wilczek calculation. The twist-3 reduced matrix elements d2p d2n are less than two standard deviations zero. data inconsistent with Burkhardt–Cottingham sum rule if there is no pathological behavior as x→0....
High precision measurements of the differential cross sections for π0 photoproduction at forward angles two nuclei, 12C and 208Pb, have been performed incident photon energies 4.9-5.5 GeV to extract π0→γγ decay width. The experiment was done Jefferson Lab using Hall B tagger a high-resolution multichannel calorimeter. width extracted by fitting measured recently updated theoretical models process. resulting value is Γ(π0→γγ)=7.82±0.14(stat)±0.17(syst) eV. With 2.8% total uncertainty, this...
New cross sections for the reaction e p-->e p eta are reported total center of mass energy W = 1.5--1.86 GeV and invariant momentum transfer Q2 0.25--1.5 (GeV/c)(2). This large kinematic range allows extraction important new information about response functions, photocouplings, N coupling strengths baryon resonances. Newly observed structure at approximately 1.65 is shown to come from interference between S P waves can be interpreted with known Improved values derived photon amplitude...
We report measurements of the photon beam asymmetry $\Sigma$ for reactions $\vec{\gamma}p\to p\pi^0$ and p\eta $ from GlueX experiment using a 9 GeV linearly-polarized, tagged incident on liquid hydrogen target in Jefferson Lab's Hall D. The asymmetries, measured as function proton momentum transfer, possess greater precision than previous $\pi^0$ are first $\eta$ this energy regime. results compared with theoretical predictions based $t$-channel, quasi-particle exchange constrain...
The GlueX experiment at Jefferson Lab ran with its first commissioning beam in late 2014 and the spring of 2015. Data were collected on both plastic liquid hydrogen targets, much detector has been commissioned. All systems are now performing or near design specifications events being fully reconstructed, including exclusive production π0, η ω mesons. Linearly-polarized photons successfully produced through coherent bremsstrahlung polarization transfer to ρ observed.