809 research outputs found
Research and development program for a combined carbon dioxide removal and reduction system. Supplement 1, phase 2a - Physicochemical properties of lithium chloride lithium carbonate melt mixtures
Physiochemical properties of liquid mixtures of lithium chloride and lithium carbonat
Knowledge and attitudes of nursing staff and mothers towards kangaroo mother care in the eastern sub-district of Cape Town
Objectives: To determine the knowledge and attitude of nursing staff and mothers towards kangaroo mother care (KMC) in the eastern sub-district of Cape Town.Design: A cross-sectional descriptive study.Setting and subjects: A multi-stage sample of 30 kangaroo care mothers admitted to the Helderberg District Hospital (HDH); six nurses from the HDH; and nine nurses from the seven antenatal clinics that the mothers attended. The respondents were interviewed using a pretested questionnaire.Outcome measures: Knowledge, attitudes and acceptability of KMC.Results: Data were analysed using CDC Epi Info version 3.3.2, and Microsoft Excel software programmes. The majority of the mothers (83.3%) did not have prior knowledge of KMC. Sixty per cent of the nursing staff did not have any KMC training. The majority of the mothers were committed to KMC, were satisfied with the results (with regard to the weight gain of the infant), and indicated that they would continue to practise KMC at home. The majority of the hospital nursing staff was very positive toward KMC, and agreed that it was beneficial to both mother and infant.Conclusion: Most of the mothers lacked prior knowledge of KMC, and were only informed about it when they were admitted to the KMC ward. All of the nursing staff who were engaged in KMC (n = 15) had a positive attitude towards it.Keywords: kangaroo mother care, low birthweight infants, nursing staf
A Solution to the Graceful Exit Problem in Pre-Big Bang Cosmology
We examine the string cosmology equations with a dilaton potential in the
context of the Pre-Big Bang Scenario with the desired scale factor duality, and
give a generic algorithm for obtaining solutions with appropriate evolutionary
properties. This enables us to find pre-big bang type solutions with suitable
dilaton behaviour that are regular at , thereby solving the graceful exit
problem. However to avoid fine tuning of initial data, an `exotic' equation of
state is needed that relates the fluid properties to the dilaton field. We
discuss why such an equation of state should be required for reliable dilaton
behaviour at late times.Comment: 16 pages LaTeX, 5 figures. To appear in Physical Review
Bounce Conditions in f(R) Cosmologies
We investigate the conditions for a bounce to occur in
Friedmann-Robertson-Walker cosmologies for the class of fourth order gravity
theories. The general bounce criterion is determined and constraints on the
parameters of three specific models are given in order to obtain bounces
solutions. It is found that unlike the case of General Relativity, a bounce
appears to be possible in open and flat cosmologies.Comment: 11 pages LaTe
Cutting Ties with Pro-Ana: A Narrative Inquiry Concerning the Experiences of Pro-Ana Disengagement from Six Former Site Users.
Websites advocating the benefits of eating disorders (“Pro-Ana”) tend to reinforce and maintain restrictive eating and purging behaviors. Yet remarkably, no study has explored individual accounts of disengagement from these sites and the associated meanings. Using narrative inquiry, this study sought to address this gap. From the interviews of six women, two overarching storylines emerged. The first closely tied disengagement to recovery with varying positions of personal agency claimed: this ranged from enforced and unwelcomed breaks that ignited change, to a personal choice that became viable through the development of alternative social and personal identities. A strong counternarrative to “disengagement as recovery” also emerged. Here, disengagement from Pro-Ana was storied alongside a need to retain an ED lifestyle. With “recovery” being just one reason for withdrawal from Pro-Ana sites, clinicians must remain curious about the meanings individuals ascribe to this act, without assuming it represents a step toward recovery.Peer reviewedFinal Accepted Versio
Bounce behaviour in Kantowski-Sachs and Bianchi Cosmologies
Many cosmological scenarios envisage either a bounce of the universe at early
times, or collapse of matter locally to form a black hole which re-expands into
a new expanding universe region. Energy conditions preclude this happening for
ordinary matter in general relativistic universes, but scalar or dilatonic
fields can violate some of these conditions, and so could possibly provide
bounce behaviour. In this paper we show that such bounces cannot occur in
Kantowski-Sachs models without violating the {\it reality condition}
. This also holds true for other isotropic spatially
homogenous Bianchi models, with the exception of closed
Friedmann-Robertson-Walker and Bianchi IX models; bounce behaviour violates the
{\em weak energy condition} and . We turn to the
Randall-Sundrum type braneworld scenario for a possible resolution of this
problem.Comment: Matches published versio
Brane Dynamics in the Randall-Sundrum model, Inflation and Graceful Exit
We study the averaged action of the Randall-Sundrum model with a time
dependent metric ansatz. It can be reformulated in terms of a Brans-Dicke
action with time dependent Newton's constant. We show that the physics of early
universe, particularly inflation, is governed by the Brans-Dicke theory. The
Brans-Dicke scalar, however, quickly settles to its equilibrium value and
decouples from the post-inflationary cosmology. The deceleration parameter is
negative to start with but changes sign before the Brans-Dicke scalar settles
to its equilibrium value. Consequently, the brane metric smoothly exits
inflation. We have also studied the slow-roll inflation in our model and
investigated the spectra of the density perturbation generated by the radion
field and find them consistent with the current observations.Comment: Revised version, Accepted in Class. Quant. Gravit
Caustics of Compensated Spherical Lens Models
We consider compensated spherical lens models and the caustic surfaces they
create in the past light cone. Examination of cusp and crossover angles
associated with particular source and lens redshifts gives explicit lensing
models that confirm previous claims that area distances can differ by
substantial factors from angular diameter distances even when averaged over
large angular scales. `Shrinking' in apparent sizes occurs, typically by a
factor of 3 for a single spherical lens, on the scale of the cusp caused by the
lens; summing over many lenses will still leave a residual effect.Comment: 21 pages, 5 ps figures, eps
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