Social Capital: A review from an ethics perspective

In this paper we extend previous reviews of the social capital literature to encompass an ethics perspective. First, we update previous reviews of social capital. Social capital continues to gain currency in both academic and practical circles, despite relatively little critical reflection on the implications of promoting this popular concept. Our work goes some way to rectifying this paucity in understanding what has been termed the ‘dark side’ of social capital. In particular, we review the social capital concept from the perspective of three theories of business ethics: utilitarianism, justice and ethic of care. While the utilitarian perspective closely parallels accounts of social capital’s rationale, the concept’s operation is mirrored very closely by the assumptions underpinning the ethic of care, while the dark side of social capital is commonly given voice in justice-based critiques. We conclude by considering the implications of our analysis

Analysis of a Helmholtz preconditioning problem motivated by uncertainty quantification

This paper analyses the following question: let $\mathbf{A}_j$, $j=1,2,$ be the Galerkin matrices corresponding to finite-element discretisations of the exterior Dirichlet problem for the heterogeneous Helmholtz equations $\nabla\cdot (A_j \nabla u_j) + k^2 n_j u_j= -f$. How small must $\|A_1 -A_2\|_{L^q}$ and $\|{n_1} - {n_2}\|_{L^q}$ be (in terms of $k$-dependence) for GMRES applied to either $(\mathbf{A}_1)^{-1}\mathbf{A}_2$ or $\mathbf{A}_2(\mathbf{A}_1)^{-1}$ to converge in a $k$-independent number of iterations for arbitrarily large $k$? (In other words, for $\mathbf{A}_1$ to be a good left- or right-preconditioner for $\mathbf{A}_2$?). We prove results answering this question, give theoretical evidence for their sharpness, and give numerical experiments supporting the estimates. Our motivation for tackling this question comes from calculating quantities of interest for the Helmholtz equation with random coefficients $A$ and $n$. Such a calculation may require the solution of many deterministic Helmholtz problems, each with different $A$ and $n$, and the answer to the question above dictates to what extent a previously-calculated inverse of one of the Galerkin matrices can be used as a preconditioner for other Galerkin matrices

A contextual approach to trauma experience: lessons from life events research

There has been much debate over what constitutes trauma experience and how this is differentiated from other very negative life events in the diagnosis of PTSD. We believe the DSM implication that trauma events are uniquely different from other types of negative life events and are limited to a few specific types of predetermined event identified categorically hinders the utility of current trauma definitions in research and practice. Whilst we do not take issue with the standard definition of trauma events, a binary checklist-style approach to identifying such events has a potential for missing relevant experience. Instead, we argue that trauma events should be considered to be at one end of a continuum of threat/severity, with potential for more or less ‘threat to life’ in a range of domains. Furthermore, a wider assessment of events could elucidate a greater range of co-existing trauma events, those sub-threshold experiences related to phasing of trauma, and other unrelated negative life events which may contribute to context and impact. In this critique of definitions of trauma events we argue that the current definition of PTSD criterion-A events limits their utility in both research and clinical practice. Following intensive life event assessments such as the LEDS (Life Events and Difficulties Schedule) the application of dimensions underlying a cross spectrum of events includes loss (of person, role, plan or ideas about the self), danger (future loss/threat to security), humiliation (devaluation of self/rejection) and entrapment (sense of imprisonment) can be used to further categorise events or trauma, and specify their likely impact. Data is provided of the overlap of ‘markedly’ threatening negative events (using the LEDS) and those constituting trauma using a commonly used checklist in a high-risk community sample of women. This yielded high specificity (97%; CI = 95.60-97.71) but low sensitivity (41%; (95% CI = 27.57-54.97) with around a third rated on both. Most of the trauma events involved loss and danger categorisation and only in one instance humiliation. Other markedly threatening, non-trauma events, involved not only loss and danger but also humiliation and entrapment. We discuss how a more in-depth assessment of trauma events utilising these dimensions and with the new Computerised Life Events Assessment Record (CLEAR), could aid us in our understanding of trauma events and lead to more personalised treatment possibilities

Attachment style, loneliness and depression in older age women

This study explores whether attachment, especially avoidant styles, might be a predictor of social support, loneliness and depression in old age

Numerical Computation of the Complex Eigenvalues of a Matrix by solving a Square System of Equations

It is well known that if the largest or smallest eigenvalue of a matrix has been computed by some numerical algorithms and one is interested in computing the corresponding eigenvector, one method that is known to give such good approximations to the eigenvector is inverse iteration with a shift. For complex eigenpairs, instead of using Ruhe’s normalization, we show that the natural two norm normalization for the matrix pencil, yields an underdetermined system of equation and by adding an extra equation, the augmented system becomes square which can be solved by LU factorization at a cheaper rate and quadratic convergence is guaranteed. While the underdetermined system of equations can be solved using QR factorization as shown in an earlier work by the same authors, converting it to a square system of equations has the added advantage that besides using LU factorization, it can be solved by several approaches including iterative methods. We show both theoretically and numerically that both algorithms are equivalent in the absence of roundoff errors

Musculoskeletal Geometry, Muscle Architecture and Functional Specialisations of the Mouse Hindlimb

Mice are one of the most commonly used laboratory animals, with an extensive array of disease models in existence, including for many neuromuscular diseases. The hindlimb is of particular interest due to several close muscle analogues/homologues to humans and other species. A detailed anatomical study describing the adult morphology is lacking, however. This study describes in detail the musculoskeletal geometry and skeletal muscle architecture of the mouse hindlimb and pelvis, determining the extent to which the muscles are adapted for their function, as inferred from their architecture. Using I2KI enhanced microCT scanning and digital segmentation, it was possible to identify 39 distinct muscles of the hindlimb and pelvis belonging to nine functional groups. The architecture of each of these muscles was determined through microdissections, revealing strong architectural specialisations between the functional groups. The hip extensors and hip adductors showed significantly stronger adaptations towards high contraction velocities and joint control relative to the distal functional groups, which exhibited larger physiological cross sectional areas and longer tendons, adaptations for high force output and elastic energy savings. These results suggest that a proximo-distal gradient in muscle architecture exists in the mouse hindlimb. Such a gradient has been purported to function in aiding locomotor stability and efficiency. The data presented here will be especially valuable to any research with a focus on the architecture or gross anatomy of the mouse hindlimb and pelvis musculature, but also of use to anyone interested in the functional significance of muscle design in relation to quadrupedal locomotion