1,171 research outputs found
Designing an optometric curriculum
This project will design an optometric curriculum for a theoretical college of optometry. The curriculum will be constructed from a students point of view while conforming to real world limitations
Domain walls and instantons in N=1, d=4 supergravity
We study the supersymmetric sources of (multi-) domain-wall and (multi-)
instanton solutions of generic N=1, d=4 supergravities, that is: the
worldvolume effective actions for said supersymmetric topological defects. The
domain-wall solutions naturally couple to the two 3-forms recently found as
part of the N=1, d=4 tensor hierarchy (i.e. they have two charges in general)
and their tension is the absolute value of the superpotential section L. The
introduction of sources (we study sources with finite and vanishing thickness)
is equivalent to the introduction of local coupling constants and results in
dramatic changes of the solutions. Our results call for a democratic
reformulation of N=1,d=4 supergravity in which coupling constants are,
off-shell, scalar fields. The effective actions for the instantons are always
proportional to the coordinate orthogonal to the twist-free embedding of the
null-geodesic (in the Wick-rotated scalar manifold) describing the instanton.
We show their supersymmetry and find the associated supersymmetric (multi-)
instanton solutions.Comment: 34 pages, 4 figures, references adde
When outcome is a balance: methods to measure combined utility for the choice between induction of labour and expectant management in mild risk pregnancy at term
Background: When the primary and secondary outcomes of clinical studies yield ambiguous or conflicting recommendations, preference or valuation studies may help to overcome the decision problem. The present preference study is attached to two clinical studies (DIGTAT, ISRCT10363217; HYPITAT, ISRCT08132825) that evaluate induction of labour versus expectant management in term pregnancies with a mild risk profile. The purpose of the present study is to compare four methods of valuation/preference measurement. Met
Optimization of diagnostic imaging use in patients with acute abdominal pain (OPTIMA): Design and rationale
<p>Abstract</p> <p>Background</p> <p>The acute abdomen is a frequent entity at the Emergency Department (ED), which usually needs rapid and accurate diagnostic work-up. Diagnostic work-up with imaging can consist of plain X-ray, ultrasonography (US), computed tomography (CT) and even diagnostic laparoscopy. However, no evidence-based guidelines exist in current literature. The actual diagnostic work-up of a patient with acute abdominal pain presenting to the ED varies greatly between hospitals and physicians. The OPTIMA study was designed to provide the evidence base for constructing an optimal diagnostic imaging guideline for patients with acute abdominal pain at the ED.</p> <p>Methods/design</p> <p>Thousand consecutive patients with abdominal pain > 2 hours and < 5 days will be enrolled in this multicentre trial. After clinical history, physical and laboratory examination all patients will undergo a diagnostic imaging protocol, consisting of plain X-ray (upright chest and supine abdomen), US and CT. The reference standard will be a post hoc assignment of the final diagnosis by an expert panel. The focus of the analysis will be on the added value of the imaging modalities over history and clinical examination, relative to the incremental costs.</p> <p>Discussion</p> <p>This study aims to provide the evidence base for the development of a diagnostic algorithm that can act as a guideline for ED physicians to evaluate patients with acute abdominal pain.</p
Pregnant women with bronchial asthma benefit from progressive muscle relaxation: A randomized, prospective, controlled trial
Background: Asthma is a serious medical problem in pregnancy and is often associated with stress, anger and poor quality of life. The aim of this study was to determine the efficacy of progressive muscle relaxation (PMR) on change in blood pressure, lung parameters, heart rate, anger and health-related quality of life in pregnant women with bronchial asthma. Methods: We treated a sample of 64 pregnant women with bronchial asthma from the local population in an 8-week randomized, prospective, controlled trial. Thirty-two were selected for PMR, and 32 received a placebo intervention. The systolic blood pressure, forced expiratory volume in the first second, peak expiratory flow and heart rate were tested, and the State-Trait Anger Expression Inventory and Health Survey (SF-36) were employed. Results: According to the intend-to-treat principle, a significant reduction in systolic blood pressure and a significant increase in both forced expiratory volume in the first second and peak expiratory flow were observed after PMR. The heart rate showed a significant increase in the coefficient of variation, root mean square of successive differences and high frequency ranges, in addition to a significant reduction in low and middle frequency ranges. A significant reduction on three of five State-Trait Anger Expression Inventory scales, and a significant increase on seven of eight SF-36 scales were observed. Conclusions: PMR appears to be an effective method to improve blood pressure, lung parameters and heart rate, and to decrease anger levels, thus enhancing health-related quality of life in pregnant women with bronchial asthma. Copyright (c) 2006 S. Karger AG, Basel
The Dark Side of the Electroweak Phase Transition
Recent data from cosmic ray experiments may be explained by a new GeV scale
of physics. In addition the fine-tuning of supersymmetric models may be
alleviated by new O(GeV) states into which the Higgs boson could decay. The
presence of these new, light states can affect early universe cosmology. We
explore the consequences of a light (~ GeV) scalar on the electroweak phase
transition. We find that trilinear interactions between the light state and the
Higgs can allow a first order electroweak phase transition and a Higgs mass
consistent with experimental bounds, which may allow electroweak baryogenesis
to explain the cosmological baryon asymmetry. We show, within the context of a
specific supersymmetric model, how the physics responsible for the first order
phase transition may also be responsible for the recent cosmic ray excesses of
PAMELA, FERMI etc. We consider the production of gravity waves from this
transition and the possible detectability at LISA and BBO
Criminal and Noncriminal Psychopathy: The Devil is in the Detail
Brooks, NS ORCiD: 0000-0003-1784-099XPsychopathy is prevalent and problematic in criminal populations, but is also found to be present in noncriminal populations. In 1992, Robert Hare declared that psychopaths may also “be found in the boardroom”, which has since been followed by an interest in the issue of noncriminal, or even successful, psychopathy. In this chapter, the paradox of criminal and noncriminal psychopathy is discussed with specific attention given to the similarities and differences that account for psychopathic personality across contexts. That psychopathy is a condition typified by a constellation of traits and behaviours requires wider research across diverse populations, and thus the streams of research related to criminal and noncriminal psychopathy are presented and the implications of these contrasting streams are explored
The episodic random utility model unifies time trade-off and discrete choice approaches in health state valuation
ABSTRACT:
BACKGROUND: To present an episodic random utility model that unifies time trade-off and discrete choice approaches in health state valuation.
METHODS: First, we introduce two alternative random utility models (RUMs) for health preferences: the episodic RUM and the more common instant RUM. For the interpretation of time trade-off (TTO) responses, we show that the episodic model implies a coefficient estimator, and the instant model implies a mean slope estimator. Secondly, we demonstrate these estimators and the differences between the estimates for 42 health states using TTO responses from the seminal Measurement and Valuation in Health (MVH) study conducted in the United Kingdom. Mean slopes are estimates with and without Dolan's transformation of worse-than-death (WTD) responses. Finally, we demonstrate an exploded probit estimator, an extension of the coefficient estimator for discrete choice data that accommodates both TTO and rank responses.
RESULTS: By construction, mean slopes are less than or equal to coefficients, because slopes are fractions and, therefore, magnify downward errors in WTD responses. The Dolan transformation of WTD responses causes mean slopes to increase in similarity to coefficient estimates, yet they are not equivalent (i.e., absolute mean difference = 0.179). Unlike mean slopes, coefficient estimates demonstrate strong concordance with rank-based predictions (Lin's rho = 0.91). Combining TTO and rank responses under the exploded probit model improves the identification of health state values, decreasing the average width of confidence intervals from 0.057 to 0.041 compared to TTO only results.
CONCLUSION: The episodic RUM expands upon the theo
All the timelike supersymmetric solutions of all ungauged d=4 supergravities
We determine the form of all timelike supersymmetric solutions of all N
greater or equal than 2, d=4 ungauged supergravities, for N less or equal than
4 coupled to vector supermultiplets, using the $Usp(n+1,n+1)-symmetric
formulation of Andrianopoli, D'Auria and Ferrara and the spinor-bilinears
method, while preserving the global symmetries of the theories all the way. As
previously conjectured in the literature, the supersymmetric solutions are
always associated to a truncation to an N=2 theory that may include
hypermultiplets, although fields which are eliminated in the truncations can
have non-trivial values, as is required by the preservation of the global
symmetry of the theories. The solutions are determined by a number of
independent functions, harmonic in transverse space, which is twice the number
of vector fields of the theory (n+1). The transverse space is flat if an only
if the would-be hyperscalars of the associated N=2 truncation are trivial.Comment: v3: Some changes in the introduction. Version to be published in JHE
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