94,499 research outputs found
Investigating presentational change in UK annual reports: a longitudinal perspective
This article examines structural and format changes in annual reports of U.K. listed companies from 1965 to 2004 with a particular focus on graph use. The article compares a new sample of 2004 annual reports with preexisting samples by Lee and by Beattie and Jones. Lee's identified trends continue. There has been a sharp increase in page length, voluntary information, and narrative information, particularly among large listed companies. A detailed analysis of voluntary disclosure indicates changes in the incidence and pattern of generic sections. Graph usage is now universal. However, key financial graph use has slightly declined, replaced by graphs depicting other operating issues. Impression management through selectivity, graphical measurement distortion, and manipulation of the length of time series graphed are common. Overall, annual reports continue to exhibit many features of public relations documents rather than financially driven, statutory documents, and the analysis of graph usage suggests a need for policy guidelines to protect users
Exact solutions for a universal set of quantum gates on a family of iso-spectral spin chains
We find exact solutions for a universal set of quantum gates on a scalable
candidate for quantum computers, namely an array of two level systems. The
gates are constructed by a combination of dynamical and geometrical
(non-Abelian) phases. Previously these gates have been constructed mostly on
non-scalable systems and by numerical searches among the loops in the manifold
of control parameters of the Hamiltonian.Comment: 1 figure, Latex, 8 pages, Accepted for publication in Physical Review
Nano-scale analysis of titanium dioxide fingerprint-development powders
Titanium dioxide based powders are regularly used in the development of latent fingerprints on dark surfaces. For analysis of prints on adhesive tapes, the titanium dioxide is suspended in a surfactant and used in the form of a small particle reagent (SPR). Analysis of commercially available products shows varying levels of effectiveness of print development, with some powders adhering to the background as well as the print. Scanning electron microscopy (SEM) images of prints developed with different powders show a range of levels of aggregation of particles.
Analytical transmission electron microscopy (TEM) of the fingerprint powder shows TiO2 particles with a surrounding coating, tens of nanometres thick, consisting of Al and Si rich material. X ray photoelectron spectroscopy (XPS) is used to determine the composition and chemical state of the surface of the powders; with a penetration depth of approximately 10nm, this technique demonstrates differing Ti: Al: Si ratios and oxidation states between the surfaces of different powders. Levels of titanium detected with this technique demonstrate variation in the integrity of the surface coating. The thickness, integrity and composition of the Al/Si-based coating is related to the level of aggregation of TiO2 particles and efficacy of print development
A High Phase Advance Damped and Detuned Structure for the Main Linacs of Clic
The main accelerating structures for the CLIC are designed to operate at an
average accelerating gradient of 100 MV/m. The accelerating frequency has been
optimised to 11.994 GHz with a phase advance of 2{\pi}/3 of the main
accelerating mode. The moderately damped and detuned structure (DDS) design is
being studied as an alternative to the strongly damped WDS design. Both these
designs are based on the nominal accelerating phase advance. Here we explore
high phase advance (HPA) structures in which the group velocity of the rf
fields is reduced compared to that of standard (2{\pi}/3) structures. The
electrical breakdown strongly depends on the fundamental mode group velocity.
Hence it is expected that electrical breakdown is less likely to occur in the
HPA structures. We report on a study of both the fundamental and dipole modes
in a CLIC_DDS_HPA structure, designed to operate at 5{\pi}/6 phase advance per
cell. Higher order dipole modes in both the standard and HPA structures are
also studied
A shock wave study of Coconino sandstone
Hugoniot equation of state measurements from shock wave loading study of Coconino sandston
Turning the Quantum Group Invariant XXZ Spin-Chain Hermitian: A Conjecture on the Invariant Product
This is a continuation of a previous joint work with Robert Weston on the
quantum group invariant XXZ spin-chain (math-ph/0703085). The previous results
on quasi-Hermiticity of this integrable model are briefly reviewed and then
connected with a new construction of an inner product with respect to which the
Hamiltonian and the representation of the Temperley-Lieb algebra become
Hermitian. The approach is purely algebraic, one starts with the definition of
a positive functional over the Temperley-Lieb algebra whose values can be
computed graphically. Employing the Gel'fand-Naimark-Segal (GNS) construction
for C*-algebras a self-adjoint representation of the Temperley-Lieb algebra is
constructed when the deformation parameter q lies in a special section of the
unit circle. The main conjecture of the paper is the unitary equivalence of
this GNS representation with the representation obtained in the previous paper
employing the ideas of PT-symmetry and quasi-Hermiticity. An explicit example
is presented.Comment: 12 page
Enhanced coupling design of a detuned damped structure for clic
The key feature of the improved coupling design in the Damped Detuned
Structure (DDS) is focused on the four manifolds. Rectangular geometry slots
and rectangular manifolds are used. This results in a significantly stronger
coupling to the manifolds compared to the previous design. We describe the new
design together with its wakefield damping properties.Comment: 3 pages, 8 figures, submitted to IPAC1
Adiposity is associated with blunted cardiovascular, neuroendocrine and cognitive responses to acute mental stress
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits
unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited - Copyright @ 2012 Jones et al.Obesity and mental stress are potent risk factors for cardiovascular disease but their relationship with each other is unclear. Resilience to stress may differ according to adiposity. Early studies that addressed this are difficult to interpret due to conflicting findings and limited methods. Recent advances in assessment of cardiovascular stress responses and of fat distribution allow accurate assessment of associations between adiposity and stress responsiveness. We measured responses to the Montreal Imaging Stress Task in healthy men (N=43) and women (N=45) with a wide range of BMIs. Heart rate (HR) and blood pressure (BP) measures were used with novel magnetic resonance measures of stroke volume (SV), cardiac output (CO), total peripheral resistance (TPR) and arterial compliance to assess cardiovascular responses. Salivary cortisol and the number and speed of answers to mathematics problems in the task were used to assess neuroendocrine and cognitive responses, respectively. Visceral and subcutaneous fat was measured using T2*-IDEAL. Greater BMI was associated with generalised blunting of cardiovascular (HR:β=â0.50 bpm.unitâ1, P=0.009; SV:β=â0.33 mL.unitâ1, P=0.01; CO:β=â61 mL.minâ1.unitâ1, P=0.002; systolic BP:β=â0.41 mmHg.unitâ1, P=0.01; TPR:β=0.11 WU.unitâ1, P=0.02), cognitive (correct answers: r=â0.28, P=0.01; time to answer: r=0.26, P=0.02) and endocrine responses (cortisol: r=â0.25, P=0.04) to stress. These associations were largely determined by visceral adiposity except for those related to cognitive performance, which were determined by both visceral and subcutaneous adiposity. Our findings suggest that adiposity is associated with centrally reduced stress responsiveness. Although this may mitigate some long-term health risks of stress responsiveness, reduced performance under stress may be a more immediate negative consequence.This work is funded by the UK National Institute of Health Research (NIHR), Siemens Medical Systems, British Heart
Foundation (BHF), NIHR Senior Research Fellowship & The Fondation Leducq, BHF Intermediate Fellowship
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