Publications by authors named "LJ Lewis"

The manufacturing process of regulatory T (Treg) cells for clinical application begins with the positive selection of CD25 cells using superparamagnetic iron oxide nanoparticle (SPION)-conjugated anti-CD25 antibodies (spCD25) and immunomagnetic cell separation technology. Our findings revealed that the interaction of spCD25 with its cell target induced the internalization of the complex spCD25-interleukin-2 receptor. Accumulation of intracellular spCD25 triggered oxidative stress, causing delayed Treg expansion and temporary reduction in suppressor activity.

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Background: Regulatory T cell (Treg) therapy is considered an alternative approach to induce tolerance in transplantation. If successful, this therapy may have implications on immunosuppression minimization/withdrawal to reduce drug-induced toxicity in patients. The aim of this study was to assess the efficacy of the mTORC1/C2 inhibitor, AZD8055, in the manufacturing of clinically competent Treg cells and compare the effects with those induced by rapamycin (RAPA), another mTOR inhibitor commonly used in Treg expansion protocols.

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Background: The use of behavioural science and behaviour change within local authorities and public health has supported healthful change; as evidenced by its importance and contribution to reducing harm during the COVID-19 pandemic. It can provide valuable information to enable the creation of evidence-based intervention strategies, co-created with the people they are aimed at, in an effective and efficient manner.

Aim: This study aimed to use the COM-B model to understand the Capability, Opportunity and Motivation of performing a constellation of eight COVID-19 disease prevention behaviours related to the slogans of 'Hands, Face, Space, Fresh Air'; 'Find, Isolate, Test, (FIT), and Vaccinate' in those employed in workplaces identified as high risk for transmission of the SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) to support intervention development.

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Introduction: The emergence of COVID-19 and the importance of behaviour change to limit its spread created an urgent need to apply behavioural science to public health. Knowledge mobilisation, the processes whereby research leads to useful findings that are implemented to affect positive outcomes, is a goal for researchers, policy makers and practitioners alike. This study aimed to explores the experience of using behavioural science in public health during COVID-19, to discover barriers and facilitators and whether the rapidly changing context of COVID-19 influenced knowledge mobilisation.

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Background: Public health emergencies require rapid responses from experts. Differing viewpoints are common in science, however, "mixed messaging" of varied perspectives can undermine credibility of experts; reduce trust in guidance; and act as a barrier to changing public health behaviours. Collation of a unified voice for effective knowledge creation and translation can be challenging.

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Climate warming is driving changes in species distributions and community composition. Many species have a so-called climatic debt, that is, shifts in range lag behind shifts in temperature isoclines. Inside protected areas (PAs), community changes in response to climate warming can be facilitated by greater colonization rates by warm-dwelling species, but also mitigated by lowering extirpation rates of cold-dwelling species.

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The ion-ion dynamical structure factor and the equation of state of warm dense aluminum in a two-temperature quasiequilibrium state, with the electron temperature higher than the ion temperature, are investigated using molecular-dynamics simulations based on ion-ion pair potentials constructed from a neutral pseudoatom model. Such pair potentials based on density functional theory are parameter-free and depend directly on the electron temperature and indirectly on the ion temperature, enabling efficient computation of two-temperature properties. Comparison with ab initio simulations and with other average-atom calculations for equilibrium aluminum shows good agreement, justifying a study of quasiequilibrium situations.

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We study the conductivities σ of (i) the equilibrium isochoric state σ_{is}, (ii) the equilibrium isobaric state σ_{ib}, and also the (iii) nonequilibrium ultrafast matter state σ_{uf} with the ion temperature T_{i} less than the electron temperature T_{e}. Aluminum, lithium, and carbon are considered, being increasingly complex warm dense matter systems, with carbon having transient covalent bonds. First-principles calculations, i.

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Using the two-temperature model for ultrafast matter (UFM), we compare the equation of state, pair-distribution functions g(r), and phonons using the neutral pseudoatom (NPA) model with results from density functional theory (DFT) codes and molecular dynamics (MD) simulations for Al, Li, and Na. The NPA approach uses state-dependent first-principles pseudopotentials from an "all-electron" DFT calculation with finite-T exchange-correlation functional (XCF). It provides pair potentials, structure factors, the "bound" and "free" states, as well as a mean ionization Z[over ¯] unambiguously.

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Ultrafast laser experiments yield increasingly reliable data on warm dense matter, but their interpretation requires theoretical models. We employ an efficient density functional neutral-pseudoatom hypernetted-chain (NPA-HNC) model with accuracy comparable to ab initio simulations and which provides first-principles pseudopotentials and pair potentials for warm-dense matter. It avoids the use of (i) ad hoc core-repulsion models and (ii) "Yukawa screening" and (iii) need not assume ion-electron thermal equilibrium.

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The nature of disorder in amorphous silicon (a-Si) is explored by investigating the spatial arrangement and energies of coordination defects in a numerical model. Spatial correlations between structural defects are examined on the basis of a parameter that quantifies the probability for two sites to share a bond. Pentacoordinated atoms are found to be the dominant coordination defects.

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Based on a detailed study of the radial distribution function (RDF) of a model for amorphous silicon (a-Si), we address the relation between short-range rearrangements and an increase in medium-range order induced by thermal relaxation. Recent experimental measurements have shown that a small peak appears in the RDF around 4.7 Å upon annealing, along with other subtle changes, and this is attributed to ordering among the dihedral angles.

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Objective: Prepartying is often associated with increased alcohol consumption and negative alcohol-related consequences among college students. General drinking motives are often only weakly related to preparty alcohol use, and few studies have examined the associations between preparty-specific drinking motives and alcohol-related consequences that occur during or after a preparty event. The current study utilizes event-level data to address this gap in the literature by examining the relationship between four types of preparty motives (prepartying to relax or loosen up, to increase control over alcohol use, to meet a dating partner, and to address concerns that alcohol may not be available later) and alcohol consequences as a function of gender.

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We study ion-damaged crystalline silicon by combining nanocalorimetric experiments with an off-lattice kinetic Monte Carlo simulation to identify the atomistic mechanisms responsible for the structural relaxation over long time scales. We relate the logarithmic relaxation, observed in a number of disordered systems, with heat-release measurements. The microscopic mechanism associated with this logarithmic relaxation can be described as a two-step replenish and relax process.

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We have computed current-current correlation functions in chains of anharmonic oscillators described by various models (FPU-β, FPU-αβ, ϕ4), considering both the total current and the currents associated with individual phonon modes, which are important in view of the Green-Kubo relation for heat conductivity. Our simulations show that, contrary to the common hypothesis, there are, under some circumstances, significant correlations between neighboring modes. These cross-mode correlations are the dominant contribution to the conductivity in the low anharmonicity regime.

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Protective behavioral strategies (PBS) are skills that can be used to reduce the risk of alcohol-related negative consequences. Studies have shown that, in general, PBS are related to less alcohol consumption and fewer negative consequences; however, other studies have suggested that not all types of PBS (e.g.

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Treacy and Borisenko (Reports, 24 February 2012, p. 950) argue from reverse Monte Carlo modeling of electron diffraction and fluctuation electron microscopy data that amorphous silicon is paracrystalline and not described by a continuous random network. However, their models disagree with high-resolution x-ray measurements and other evidence, whereas the agreement with fluctuation electron microscopy is at best qualitative.

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We investigate the problem of heat conduction across molecular junctions connecting two nanoparticles, both in vacuum and in a liquid environment, using classical molecular dynamics simulations. In vacuum, the well-known result of a length independent conductance is recovered; its precise value, however, is found to depend sensitively on the overlap between the vibrational spectrum of the junction and the density of states of the nanoparticles that act as thermal contacts. In a liquid environment, the conductance is constant up to a crossover length, above which a standard Fourier regime is recovered.

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As our understanding of genetics has grown, and its importance has increased in clinical care, pregnancy and the fetus are often seen through a genetic lens. Clinicians who care for pregnant women are charged with explaining genetic risk and overseeing prenatal screening. For the clinician, genetics represents clearly defined application of a particular kind of scientific knowledge.

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We study heat transfer from a heated nanoparticle into surrounding fluid using molecular dynamics simulations. We show that the fluid next to the nanoparticle can be heated well above its boiling point without a phase change. Under increasing nanoparticle temperature, the heat flux saturates, which is in sharp contrast with the case of flat interfaces, where a critical heat flux is observed followed by development of a vapor layer and heat flux drop.

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We investigate the effect of interactions between inclusions on the coarsening behavior of elastically inhomogeneous multiphase systems with lattice misfit using a recently introduced two-dimensional multiscale model based on the classical time-dependent density-functional theory. We show that spontaneous shape changes are very efficient in limiting the impact of the interactions on the chemical potential of inclusions. For this reason, the interactions between isolated pairs of inclusions are unable to significantly affect coarsening.

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With a view of finding a route toward microstructural stability in alloys, we numerically study the impact of elastic inhomogeneities on the growth of inclusions in multiphase systems. We show that growth can proceed either continuously at rough interfaces, or in a layer-by-layer fashion following an elastically induced kinetic faceting process. In the former case, the chemical potential of the inclusions is a smooth function of size, while in the latter case, elasticity increases the barrier for nucleation of new terraces on the facets, leading to an oscillatory behavior of the chemical potential and hence a strong resistance against coarsening, opening up the possibility to stabilize the structure.

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Using a two-dimensional multiscale model based on the classical time-dependent density-functional theory for lattice systems we recently introduced, we numerically study the impact of elastic inhomogeneities on the growth of isolated inclusions in multiphase alloys. We demonstrate that the coupling between the overall interface structure (as determined by the shape of the inclusions) and the local, atomic-scale structure can be very large, and is able to significantly affect the behavior of inclusions during growth. Elasticity is shown to have a strong influence on the local energetics at interfaces, leading to shape modulations and kinetic faceting.

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The substituted phenazines XR11576 and XR5944 were originally described as dual topoisomerase-I/II poisons. Subsequent reports, however, indicated that the association of their cytotoxicity with cellular topoisomerases was not clear. We set out to study this further using human tumour cell lines, PEO1 ovarian cancer, MDA-MB-231 breast cancer and variants with acquired resistance to VP-16 and XR11576: PEO1VPR, MB-231VPR, MB-231-11576R and camptothecin: PEO1CamR.

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