The tyranny of regional unemployment rates

Although there is a substantial body of literature on labour market analysis, most of it ignores the spatial dimension of the labour market. A spatial perspective in analysing labour market processes is important for several reasons. FIRST, labour markets are by no means as homogeneous as conventional labour market theories assume. SECOND, most countries are displaying strong regional variations in the dynamics of unemployment. THIRD, geographical space exerts a frictional effect on labour market processes. Regional unemployment rates appear to be the most important indicators for analysing labour market processes from a spatial perspective. The paper aims to discuss some of the problems that are associated with the use of regional unemployment rates. We will focus attention on conceptual problems, problems of data quality and on some of the new problems that have arisen due to the widespread use of new computer technology. Solutions to many of the problems are obvious, but many of the new problems will require some extra effort for their solution. The tyranny that threatens the research community is that regional unemployment data exercise a power over us that can lead the naive to misinterpretations. The data may mislead even the most righteous among us. A good deal of research effort is often given to overcome the tyranny that is found in the columns and rows that the lay public likes to call statistics. The discussion will be enriched by means of a study utilizing regional unemployment rates at the district level in West Germany.

Analytical and numerical techniques for wave scattering

In this thesis, we study the mathematical solution of wave scattering problems which describe the behaviour of waves incident on obstacles and are highly relevant to a raft of applications in the aerospace industry. The techniques considered in the present work can be broadly classed into two categories: analytically based methods which use special transforms and functions to provide a near-complete mathematical description of the scattering process, and numerical techniques which select an approximate solution from a general finite-dimensional space of possible candidates. The first part of this thesis addresses an analytical approach to the scattering of acoustic and vortical waves on an infinite periodic arrangement of finite-length flat blades in parallel mean flow. This geometry serves as an unwrapped model of the fan components in turbo-machinery. Our contributions include a novel semi-analytical solution based on the Wiener–Hopf technique that extends previous work by lifting the restriction that adjacent blades overlap, and a comprehensive study of the composition of the outgoing energy flux for acoustic wave scattering on this array of blades. These results provide an insight into the importance of energy conversion between the unsteady vorticity shed from the trailing edges of the cascade blades and the acoustic field. Furthermore, we show that the balance of incoming and outgoing energy fluxes of the unsteady field provides a convenient tool for understanding several interesting scattering symmetries on this geometry. In the second part of the thesis, we focus on numerical techniques based on the boundary integral method which allows us to write the governing equations for zero mean flow in the form of Fredholm integral equations. We study the solution of these integral equations using collocation methods for two-dimensional scatterers with smooth and Lipschitz boundaries. Our contributions are as follows: Firstly, we explore the extent to which least-squares oversampling can improve collocation. We provide rigorous analysis that proves guaranteed convergence for small amounts of oversampling and shows that superlinear oversampling can ensure faster asymptotic convergence rates of the method. Secondly, we examine the computation of the entries in the discrete linear system representing the continuous integral equation in collocation methods for hybrid numerical-asymptotic basis spaces on simple geometric shapes in the context of high-frequency wave scattering. This requires the computation of singular highly-oscillatory integrals and we develop efficient numerical methods that can compute these integrals at frequency-independent cost. Finally, we provide a general result that allows the construction of recurrences for the efficient computation of quadrature moments in a broad class of Filon quadrature methods, and we show how this framework can also be used to accelerate certain Levin quadrature methods.Supported by EPSRC grant EP/L016516/

Needs Assessment to Improve Sepsis Bundle Compliance in the Emergency Department

Sepsis is a leading cause of morbidity and mortality worldwide. Treatment depends on time-sensitive antibiotic initiation, fluid resuscitation, and vasoactive support. Early recognition and bundled care are core tenets of management. Thus, this project aims to identify barriers to sepsis bundle compliance in a local community emergency department. Specifically, how do perceived barriers to sepsis bundle compliance as identified by staff correspond with quantitative delays in care as demonstrated by chart data? This mixed-methods needs assessment consists of staff surveys and analysis of extracted chart data. Staff surveys revealed barriers including staffing shortages, difficulty with intravenous (IV) access, and lack of recognition in triage. Case reviews showed that many patients receive components of the 1-hour sepsis bundle before they screen SIRS+ (57% of patients for lactate draws, 34% of patients for blood culture draws, n=35). Across cases, average door-to-antibiotic time was 137.06 minutes (SD 88.66 minutes). Thus, the department has yet to meet its target of door-to-antibiotic time less than one hour. Survey data and case reviews provide a launchpad for future quality improvement (QI) initiatives in the emergency department

Accelerated epigenetic aging in Werner syndrome.

Individuals suffering from Werner syndrome (WS) exhibit many clinical signs of accelerated aging. While the underlying constitutional mutation leads to accelerated rates of DNA damage, it is not yet known whether WS is also associated with an increased epigenetic age according to a DNA methylation based biomarker of aging (the "Epigenetic Clock"). Using whole blood methylation data from 18 WS cases and 18 age matched controls, we find that WS is associated with increased extrinsic epigenetic age acceleration (p=0.0072) and intrinsic epigenetic age acceleration (p=0.04), the latter of which is independent of age-related changes in the composition of peripheral blood cells. A multivariate model analysis reveals that WS is associated with an increase in DNA methylation age (on average 6.4 years, p=0.011) even after adjusting for chronological age, gender, and blood cell counts. Further, WS might be associated with a reduction in naïve CD8+ T cells (p=0.025) according to imputed measures of blood cell counts. Overall, this study shows that WS is associated with an increased epigenetic age of blood cells which is independent of changes in blood cell composition. The extent to which this alteration is a cause or effect of WS disease phenotypes remains unknown

Wave scattering by an infinite cascade of non-overlapping blades

We consider the scattering of waves by an in finite three-dimensional cascade of fi nite-length at blades in subsonic fow at zero angle of attack. This geometry is of speci fic relevance as it provides a model for the components in turbofan engines. We study the scattering problem analytically, considering both acoustical and vortical incident fields, spanwise wavenumbers and transverse mean flow. Most importantly we extend previous work by lifting the restriction that adjacent blades overlap, a condition that had thus far been crucial for the analytical study of this problem. Our method of solution relies on the solution of three coupled boundary value problems using the Wiener-Hopf technique, corresponding to an uncoupled leading-edge approximation, and a subsequent trailing-edge and leading-edge correction. We provide exact expressions for observables in the system, depending only on the solution of a linear matrix equation. Specifi cally we find closed-form expressions for the far- field behaviour of the scattered potential upstream and downstream of the cascade, the upstream and downstream sound power, as well as the total unsteady lift on each blade in the cascade. A wide range of results are presented, and we see that the non-overlapping cascade is, as might be expected, typically more transparent to incident disturbances than the previously studied overlapping case.EPSRC grant EP/L016516/