The ‘Sticky Elastica’: Delamination blisters beyond small\ud deformations

We consider the form of an elastic loop adhered to a rigid substrate: the ‘sticky Elastica’. In contrast to previous studies of the shape of delamination ‘blisters’, the theory developed accounts for deflections with large slope (i.e. geometrically nonlinear). Starting from the classical Euler Elastica we provide numerical results for the dimensions of such blisters for a variety of end-end confinements and develop asymptotic expressions that reproduce these results well up to the point of self-contact. Interestingly, we find that the width of such blisters does not grow monotonically with increased confinement. Our theoretical predictions are confirmed by simple desktop experiments and suggest a new method for the measurement of the elastocapillary length for deformations that cannot be considered small

Switch on, switch off: stiction in nanoelectromechanical switches

We present a theoretical investigation of stiction in nanoscale electromechanical contact switches. We develop a mathematical model to describe the deflection of a cantilever beam in response to both electrostatic and van der Waals forces. Particular focus is given to the question of whether adhesive van der Waals forces cause the cantilever to remain in the ‘ON’ state even when the electrostatic forces are removed. In contrast to previous studies, our theory accounts for deflections with large slopes (i.e. geometrically nonlinear). We solve the resulting equations numerically to study how a cantilever beam adheres to a rigid electrode: transitions between free, ‘pinned’ and ‘clamped’ states are shown to be discontinuous and to exhibit significant hysteresis. Our findings are compared to previous results from linearized models and the implications for nanoelectromechanical cantilever switch design are discussed

The sensitivity of Graphene ‘Snap-through’ to substrate\ud geometry

We study theoretically the deposition of Few Layer Graphene sheets onto a grooved substrate incorporating adhesion between substrate and sheet. We develop a model to understand the equilibrium of the sheet allowing for partial conformation of sheet to substrate. This model gives new insight into recent observations of ‘snap-through’ from flat to conforming states and emphasizes the crucial role of substrate shape in determining the nature of this transition. Our analytical results are consistent with numerical simulations using a van der Waals-like interaction . Finally we propose a novel substrate shape that should exhibit a continuous, rather than ‘snap-through’, transition

Floating carpets and the delamination of elastic sheets

We investigate the deformation of a thin elastic sheet floating on a liquid surface and subject to a uniaxial compression. We show that at a critical compression the sheet delaminates from the liquid over a finite region forming a delamination ‘blister’. This blistering regime adds to the wrinkling and localized folding regimes that have been studied previously. The transition from wrinkled to blistered states occurs when delamination becomes energetically favourable compared to wrinkling. We determine the initial blister size and the evolution of blister size with continuing compression before verifying our theoretical results with experiments at a macroscopic scale

Impact for Agents

Impact for agents. Most of the agent research community has been predicting greater impact for years and many of us have been working to help the process along. Yet the tremendous growth on the research front has not been met with

Timelike deeply virtual Compton scattering with a linearly polarized real (or quasi-real) photon beam

We calculate timelike virtual Compton scattering amplitudes in the generalized Bjorken scaling regime and focus on a new polarization asymmetry in the scattering process with a linearly polarized photon beam in the medium energy range, which will be studied intensely at JLab12 experiments. We demonstrate that new observables help us to access the polarized quark and gluon generalized parton distributions $\tilde H(x, \xi, t)$ and $\tilde E(x, \xi, t)$.Comment: To appear in the proceedings XXII. International Workshop on Deep Inelastic Scattering and Related Subjects (DIS 2014), 28 April - 2 May 2014, Warsaw, Polan

Psychoanalysis and male homosexuality

This thesis explores the status of homosexuality, within the history of psychoanalysis, and the effects of that status in the development of contemporary talking therapies. Focusing on homosexuality in men, the research in this study examines Freud’s theories and concepts, as the foundation of this thesis. This paper is divided into four chapters. The first chapter is a reading of Freud and his psychogenesis of homosexuality. The second chapter is an analysis of three American analysts, who interpreted Freud’s theory of the Oedipus complex in a very particular way to make it fit for their purpose. According to these analysts homosexuality, in their view, is an illness in need of a cure. Their aim is to convert homosexuality into heterosexuality by conducting analysis on their homosexual analysands. Throughout this chapter I will be reinterpreting a case study of reparative therapy. The third chapter is a critical analysis of Richard Isay’s radical views of homosexuality. Chapter three will also introduce gay affirmative therapy; a therapy, which is aimed to help one come to terms with their homosexuality. In the fourth chapter I will critically analyse and compare a case study of reparative and gay affirmative therapy. My intentions of analysing these two case studies are to illustrate that: while they differ in their analytic approach, they share some similarities. The purpose of analysing these two therapies is that many homosexuals today undergo reparative or gay affirmative therapy. Freud’s conclusion, that homosexuality or heterosexuality is an outcome of the Oedipus complex, will play an important role in the discussion of reparative and gay affirmative therapy. His perceptions of how psychoanalysis should be conducted throughout analysis will also emphasis how far reparative and gay affirmative therapies have developed since from classical Freudian psychoanalysis