342 research outputs found
Energy absorption by "sparse" systems: beyond linear response theory
The analysis of the response to driving in the case of weakly chaotic or
weakly interacting systems should go beyond linear response theory. Due to the
"sparsity" of the perturbation matrix, a resistor network picture of
transitions between energy levels is essential. The Kubo formula is modified,
replacing the "algebraic" average over the squared matrix elements by a
"resistor network" average. Consequently the response becomes semi-linear
rather than linear. Some novel results have been obtained in the context of two
prototype problems: the heating rate of particles in Billiards with vibrating
walls; and the Ohmic Joule conductance of mesoscopic rings driven by
electromotive force. Respectively, the obtained results are contrasted with the
"Wall formula" and the "Drude formula".Comment: 8 pages, 7 figures, short pedagogical review. Proceedings of FQMT
conference (Prague, 2011). Ref correcte
Derivation of the Rules of Quantum Mechanics from Information-Theoretic Axioms
Conventional quantum mechanics with a complex Hilbert space and the Born Rule
is derived from five axioms describing properties of probability distributions
for the outcome of measurements. Axioms I,II,III are common to quantum
mechanics and hidden variable theories. Axiom IV recognizes a phenomenon, first
noted by Turing and von Neumann, in which the increase in entropy resulting
from a measurement is reduced by a suitable intermediate measurement. This is
shown to be impossible for local hidden variable theories. Axiom IV, together
with the first three, almost suffice to deduce the conventional rules but allow
some exotic, alternatives such as real or quaternionic quantum mechanics. Axiom
V recognizes a property of the distribution of outcomes of random measurements
on qubits which holds only in the complex Hilbert space model. It is then shown
that the five axioms also imply the conventional rules for all dimensions.Comment: 20 pages, 6 figure
Investigating Mitophagy and Mitochondrial Morphology In Vivo Using mito-QC:A Comprehensive Guide
An Exactly Solvable Model for the Integrability-Chaos Transition in Rough Quantum Billiards
A central question of dynamics, largely open in the quantum case, is to what
extent it erases a system's memory of its initial properties. Here we present a
simple statistically solvable quantum model describing this memory loss across
an integrability-chaos transition under a perturbation obeying no selection
rules. From the perspective of quantum localization-delocalization on the
lattice of quantum numbers, we are dealing with a situation where every lattice
site is coupled to every other site with the same strength, on average. The
model also rigorously justifies a similar set of relationships recently
proposed in the context of two short-range-interacting ultracold atoms in a
harmonic waveguide. Application of our model to an ensemble of uncorrelated
impurities on a rectangular lattice gives good agreement with ab initio
numerics.Comment: 29 pages, 5 figure
Recent advances on information transmission and storage assisted by noise
The interplay between nonlinear dynamic systems and noise has proved to be of
great relevance in several application areas. In this presentation, we focus on
the areas of information transmission and storage. We review some recent
results on information transmission through nonlinear channels assisted by
noise. We also present recent proposals of memory devices in which noise plays
an essential role. Finally, we discuss new results on the influence of noise in
memristors.Comment: To be published in "Theory and Applications of Nonlinear Dynamics:
Model and Design of Complex Systems", Proceedings of ICAND 2012 (Springer,
2014
Prevention and management of excessive gestational weight gain: a survey of overweight and obese pregnant women
Background - Excessive gestational weight gain is associated with adverse infant, childhood and maternal outcomes and research to develop interventions to address this issue is ongoing. The views of women on gestational weight gain and the resources they would consider helpful in addressing this are however largely unknown. This survey aimed to determine the views of newly pregnant women, living in areas of social disadvantage, on 1) their current body weight and potential gestational weight gain and 2) the resources or interventions they would consider helpful in preventing excessive gestational weight gain.
Methods - A convenience sample of overweight and obese pregnant women living in Fife, UK, were invited to complete a short anonymised questionnaire at their 12 week booking visit.
Results - 428 women, BMI>25 kg/m2, completed the questionnaire. Fifty-four per cent of respondents were obese (231) and 62% were living in areas of mild to moderate deprivation. Over three-quarters of participants felt dissatisfied with their current weight (81%). The majority of women (60%) expressed some concern about potential weight gain. Thirty-nine percent were unconcerned about weight gain during their pregnancy, including 34 women (19%) who reported having retained weight gained in earlier pregnancies. Amongst those concerned about weight gain advice on physical activity (41%) and access to sports/leisure facilities were favoured resources (36%). Fewer women (12%) felt that group sessions on healthy eating or attending a clinic for individualised advice (14%) would be helpful. "Getting time off work" was the most frequently cited barrier (48%) to uptake of resources other than leaflets.
Conclusions- These data suggest a lack of awareness amongst overweight and obese women regarding excessive gestational weight gain. Monitoring of gestational weight gain, and approaches for its management, should be formally integrated into routine antenatal care. Barriers to the uptake of resources to address weight gain are numerous and must be considered in the design of future interventions and services
Empathy: a review of the concept
The inconsistent definition of empathy has had a negative impact on both research and practice. The aim of this article is to review and critically appraise a range of definitions of empathy and, through considered analysis, to develop a new conceptualisation. From the examination of 43 discrete definitions, 8 themes relating to the nature of empathy emerged: “distinguishing empathy from other concepts”; “cognitive or affective?”; “congruent or incongruent?”; “subject to other stimuli?”; “self/other distinction or merging?”; “trait or state influences?”; “has a behavioural outcome?”; and “automatic or controlled?” The relevance and validity of each theme is assessed and a new conceptualisation of empathy is offered. The benefits of employing a more consistent and complete definition of empathy are discussed
Transforming Empathy to Empathetic Practice amongst Nursing and Drama Students
Nurses and actors both require the ability to demonstrate empathy in their practice. Mastering communication skills and techniques can inform an empathetic response. This skill is particularly important for nurses working in paediatric palliative and end of life care but there is lack of consensus whether empathy can be taught. The process an actor follows when getting into character incorporates drawing on personal emotive experiences and necessitates being receptive to others on stage in order to ‘journey’ from listening and empathising to actually being a character. We have translated this practice into the way we teach nursing students to communicate empathy
Is there job satisfaction in community mental health?
After discussing the importance of job satisfaction, this paper presents data concerning current levels and sources of job satisfaction in community mental health centers. Data came from a survey completed by 164 staff members working in 22 different programs located in Michigan. The return rate was 94%. Results indicated that compared to workers in other occupations, the staff were about average in satisfaction with co-workers and supervision, but low in satisfaction with the work itself. The two major sources of job satisfaction reported by staff were the level of accomplishment experienced in the work and the degree of clarity in organizational goals and policies. The paper concludes by suggesting ways in which job satisfaction in community mental health could be increased.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44298/1/10597_2004_Article_BF00778606.pd
Feminist health psychology and abortion : towards a politics of transversal relations of commonality
In 1992 Speckhard and Rue argued in the Journal of Social Issues for the recognition of a diagnostic category, post-abortion syndrome (PAS). This term was first used in 1981 by Vincent Rue in testimony to the American Congress, but was only formalised in a published paper a decade later. Speckhard and Rue (1992) posit that abortion is a psychosocial stressor that may cause mild distress through to severe trauma, creating the need for a continuum of categories, these being post-abortion distress, post-abortion syndrome and post-abortion psychosis. PAS, which is the main focus of their paper, and which has taken root in some professional language as well as lay anti-abortion discourse, is described as a type of post-traumatic stress disorder
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