111 research outputs found
The Final Act of Juliette Willoughby
No full textFrom the author of The Club, a Reese Witherspoon Book Club Pick, The Final Act of Juliette Willoughby is Ellery Lloyd's compulsive multiple - timeline mystery – a story of love and madness, of obsession and revenge. This novel was co-written by Paul Vlitos (University of Greenwich) and Collette Lyons (writing together as Ellery Lloyd). In a prestigious starred notice, the influential US journal Kirkus Review noted that: “Lloyd’s novel interweaves the stories of three distinct time periods [1930s Paris, 1990s Cambridge, present-day Dubai] to create an elegant tapestry—and a novel of love, suspense, family secrets, Egyptology, surrealism, and corruption. […] A delightful puzzle box of a novel.” The Final Act of Juliette Willoughby was also one of ’10 noteworthy books for June’ in the Washington Post, a Crime Fiction Pick of the Month in The Sunday Times – and Heat magazine’s book of the week! The novel was published on the 20th June 2024 by Macmillan in the UK and on the 11th June by Harper Collins in the US
Modelling transport through biological environments that contain obstacles
No full textTransport through biological environments that are densely crowded with obstacles is often classified as anomalous, rather than Fickian diffusion. Researchers often describe these transport processes using either a random walk model or a fractional order differential equation model. To explore these ideas, we simulate transport through a crowded environment that is populated by impenetrable immobile obstacles. Our work suggests that it may be inappropriate to model transport through a crowded environment using these standard approaches.\ud
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We develop a new analytical method for modelling the transport of an agent through a crowded environment. Using our new method, we calculate the exact long-time diffusivity as well as the crossover time, which is the time scale required for the transport process to effectively become Fickian. Finally, we extend our new model to include interactions between the motile agent and the obstacles such as adhesion and repulsion
An analytical method to solve a general class of nonlinear reactive transport models
No full textThree recent papers published in Chemical Engineering Journal studied the solution of a model of diffusion and nonlinear reaction using three different methods. Two of these studies obtained series solutions using specialized mathematical methods, known as the Adomian decomposition method and the homotopy analysis method. Subsequently it was shown that the solution of the same particular model could be written in terms of a transcendental function called Gauss’ hypergeometric function. These three previous approaches focused on one particular reactive transport model. This particular model ignored advective transport and considered one specific reaction term only. Here we generalize these previous approaches and develop an exact analytical solution for a general class of steady state reactive transport models that incorporate (i) combined advective and diffusive transport, and (ii) any sufficiently differentiable reaction term R(C). The new solution is a convergent Maclaurin series. The Maclaurin series solution can be derived without any specialized mathematical methods nor does it necessarily involve the computation of any transcendental function. Applying the Maclaurin series solution to certain case studies shows that the previously published solutions are particular cases of the more general solution outlined here. We also demonstrate the accuracy of the Maclaurin series solution by comparing with numerical solutions for particular cases
Exact series solutions of reactive transport models with general initial conditions
No full textExact solutions of partial differential equation models describing the transport and decay of single and coupled multispecies problems can provide insight into the fate and transport of solutes in saturated aquifers. Most previous analytical solutions are based on integral transform techniques, meaning that the initial condition is restricted in the sense that the choice of initial condition has an important impact on whether or not the inverse transform can be calculated exactly. In this work we describe and implement a technique that produces exact solutions for single and multispecies reactive transport problems with more general, smooth initial conditions. We achieve this by using a different method to invert a Laplace transform which produces a power series solution. To demonstrate the utility of this technique, we apply it to two example problems with initial conditions that cannot be solved exactly using traditional transform techniques
Measuring the apparent size of the Moon with a digital camera
No full textThe Moon appears to be much larger closer to the horizon than when higher in the sky. This is called the ‘Moon Illusion’ since the observed size of the Moon is not actually larger when the Moon is just above the horizon. This article describes a technique for verifying that the observed size of the Moon in not larger on the horizon. The technique can be easily performed in a high school teaching environment. Moreover, the technique demonstrates the surprising fact that the observed size of the Moon is actually smaller on the horizon due to atmospheric refraction. For the purposes of this paper, several images of the moon were taken with the Moon close to the horizon and close to the zenith. Images were processed using a free program called ImageJ. The Moon was found to be 5.73 ±0.04% smaller in area on the horizon then at the zenith
Probabilistic causality: a rejoinder to Ellery Eells
No full text© 1990 The Philosophy of Science AssociationIn an earlier paper (Dupré 1984), I criticized a thesis sometimes defended by theorists of probabilistic causality, namely, that a probabilistic cause must raise the probability of its effect in every possible set of causally relevant background conditions (the "contextual unanimity thesis"). I also suggested that a more promising analysis of probabilistic causality might be sought in terms of statis- tical relevance in a fair sample. Ellery Eells (1987) has defended the contextual unanimity thesis against my objections, and also raised objections of his own to my positive claims. In this paper I defend and amplify both my objections to the contextual unanimity thesis and my constructive suggestion
Supplementary_data – Supplemental material for Non-interventional study of the safety and effectiveness of fluticasone propionate/formoterol fumarate in real-world asthma management
No full textSupplemental material, Supplementary_data for Non-interventional study of the safety and effectiveness of fluticasone propionate/formoterol fumarate in real-world asthma management by Vibeke Backer, Adam Ellery, Sylvia Borzova, Stephen Lane, Magda Kleiberova, Peter Bengtsson, Tadeusz Tomala, Dominique Basset-Stheme, Carla Bennett, Dirk Lindner, Arthur Meiners and Tim Overend in Therapeutic Advances in Respiratory Disease</p
Moments of action provide insight into critical times for advection-diffusion-reaction processes.
No full textBerezhkovskii and co-workers introduced the concept of local accumulation time as a finite measure of the time required for the transient solution of a reaction-diffusion equation to effectively reach steady state [Biophys J. 99, L59 (2010); Phys. Rev. E 83, 051906 (2011)]. Berezhkovskii's approach is a particular application of the concept of mean action time (MAT) that was introduced previously by McNabb [IMA J. Appl. Math. 47, 193 (1991)]. Here, we generalize these previous results by presenting a framework to calculate the MAT, as well as the higher moments, which we call the moments of action. The second moment is the variance of action time, the third moment is related to the skew of action time, and so on. We consider a general transition from some initial condition to an associated steady state for a one-dimensional linear advection-diffusion-reaction partial differential equation (PDE). Our results indicate that it is possible to solve for the moments of action exactly without requiring the transient solution of the PDE. We present specific examples that highlight potential weaknesses of previous studies that have considered the MAT alone without considering higher moments. Finally, we also provide a meaningful interpretation of the moments of action by presenting simulation results from a discrete random-walk model together with some analysis of the particle lifetime distribution. This work shows that the moments of action are identical to the moments of the particle lifetime distribution for certain transitions
Critical time scales for advection-diffusion-reaction processes.
No full textThe concept of local accumulation time (LAT) was introduced by Berezhkovskii and co-workers to give a finite measure of the time required for the transient solution of a reaction-diffusion equation to approach the steady-state solution [A. M. Berezhkovskii, C. Sample, and S. Y. Shvartsman, Biophys. J. 99, L59 (2010); A. M. Berezhkovskii, C. Sample, and S. Y. Shvartsman, Phys. Rev. E 83, 051906 (2011)]. Such a measure is referred to as a critical time. Here, we show that LAT is, in fact, identical to the concept of mean action time (MAT) that was first introduced by McNabb [A. McNabb and G. C. Wake, IMA J. Appl. Math. 47, 193 (1991)]. Although McNabb's initial argument was motivated by considering the mean particle lifetime (MPLT) for a linear death process, he applied the ideas to study diffusion. We extend the work of these authors by deriving expressions for the MAT for a general one-dimensional linear advection-diffusion-reaction problem. Using a combination of continuum and discrete approaches, we show that MAT and MPLT are equivalent for certain uniform-to-uniform transitions; these results provide a practical interpretation for MAT by directly linking the stochastic microscopic processes to a meaningful macroscopic time scale. We find that for more general transitions, the equivalence between MAT and MPLT does not hold. Unlike other critical time definitions, we show that it is possible to evaluate the MAT without solving the underlying partial differential equation (pde). This makes MAT a simple and attractive quantity for practical situations. Finally, our work explores the accuracy of certain approximations derived using MAT, showing that useful approximations for nonlinear kinetic processes can be obtained, again without treating the governing pde directly
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