927 research outputs found
A survey-based, descriptive study of the occupational health experience of pregnant women doctors working in the public health sector in the Western Cape from 2009-2015
THE PURPOSE OF THE STUDY is to explore the experiences of pregnant women doctors working in public sector health facilities in the Western Cape and to ascertain whether occupational health laws and guidelines are being implemented for pregnant women doctors. This is being done in order to provide feedback to Western Cape department of health, so that if found necessary, recommendations for the improved occupational health of pregnant doctors can be implemented. THE OBJECTIVES are to conduct an internet-based survey of woman doctors who have experienced pregnancies while working in the public sector. The three main objectives are: 1. To describe the demographics of the respondents 2. To explore the experiences of the respondents with regard to working while pregnant 3. To assess the knowledge of occupational and other laws that relate to pregnant women at work. HYPOTHESIS: There is currently poor implementation of occupational health laws and services for pregnant doctors in the various government health facilities in the Western Cape SIGNIFICANCE OF THIS RESEARCH: "The progress of women in medicine is a long and continuing journey," AMA Women Physicians section (Anon.2013). The number of women graduating as doctors has increased. Many of these women form the mainstay of the public-sector workforce. Attention needs to be focused on ensuring the safety of pregnant women doctors and the safety of their unborn babies. METHODOLOGY OF STUDY: Study Design: This is a retrospective, survey-based, descriptive study using an electronic survey/ questionnaire as a tool. The survey includes both set answer options from which to choose as well as areas for respondents to give comments, which will add a qualitative element to the research. CHARACTERISTICS OF THE STUDY POPULATION: The study population consists of women doctors who took maternity leave while working in the state sector in the Western Cape from 2009-2015. INCLUSION AND EXCLUSION CRITERIA: Inclusion criteria: All women who complete and submit the survey will be included in the sample. No exclusion criteria are envisioned
Vanishing of Gravitational Particle Production in the Formation of Cosmic Strings
We consider the gravitationally induced particle production from the quantum
vacuum which is defined by a free, massless and minimally coupled scalar field
during the formation of a gauge cosmic string. Previous discussions of this
topic estimate the power output per unit length along the string to be of the
order of ergs/sec/cm in the s-channel. We find that this production
may be completely suppressed. A similar result is also expected to hold for the
number of produced photons.Comment: 10 pages, Plain LaTex. Minor improvements. To appear in PR
Renormalization of the charged scalar field in curved space
The DeWitt-Schwinger proper time point-splitting procedure is applied to a
massive complex scalar field with arbitrary curvature coupling interacting with
a classical electromagnetic field in a general curved spacetime. The scalar
field current is found to have a linear divergence. The presence of the
external background gauge field is found to modify the stress-energy tensor
results of Christensen for the neutral scalar field by adding terms of the form
to the logarithmic counterterms. These results are shown to be
expected from an analysis of the degree of divergence of scalar quantum
electrodynamics.Comment: 24 pages REVTe
Smoking patterns in Great Britain: the rise of cheap cigarette brands and roll your own (RYO) tobacco
This is the final version. Available from Oxford University Press via the DOI in this record.Background
In Britain, the tobacco industry segments cigarettes into four price categories—premium, mid-price, economy and ultra-low-price (ULP). Our previous work shows that tobacco companies have kept ULP prices stable in real terms. Roll your own (RYO) tobacco remains cheaper still.
Methods
Analysis of 2001–08 General Household Survey data to examine trends in use of these cheap products and, using logistic regression, the profile of users of these products.
Results
Among smokers, the proportion using cheap products (economy, ULP and RYO combined) increased significantly in almost all age groups and geographic areas. Increases were most marked in under 24 year olds, 76% of whom smoked cheap cigarettes by 2008. All cheap products were more commonly used in lower socio-economic groups. Men and younger smokers were more likely to smoke RYO while women smoked economy brands. Smokers outside London and the South East of England were more likely to smoke some form of cheap tobacco even once socio-economic differences were accounted for.
Conclusions
This paper demonstrates that cheap tobacco use is increasing among young and disadvantaged smokers compromising declines in population smoking prevalence. Thus, tobacco industry pricing appears to play a key role in explaining smoking patterns and inequalities in smoking
Astrophysical Bounds on Global Strings
Global topological defects produce nonzero stress-energy throughout
spacetime, and as a result can have observable gravitational influence on
surrounding matter. Gravitational effects of global strings are used to place
bounds on their cosmic abundance. The minimum separation between global strings
is estimated by considering the defects' contribution to the cosmological
energy density. More rigorous constraints on the abundance of global strings
are constructed by examining the tidal forces such defects will have on
observable astrophysical systems. The small number of observed tidally
disrupted systems indicates there can be very few of these objects in the
observable universe.Comment: 14 pages, REVTe
Semiclassical Stability of the Extreme Reissner-Nordstrom Black Hole
The stress-energy tensor of a free quantized scalar field is calculated in
the extreme Reissner-Nordstr\"{o}m black hole spacetime in the zero temperature
vacuum state. The stress-energy appears to be regular on the event horizon,
contrary to the suggestion provided by two-dimensional calculations. An
analytic calculation on the event horizon for a thermal state shows that if the
temperature is nonzero then the stress-energy diverges strongly there.Comment: 10 pages, REVTeX, 4 figures in separate uuencoded compressed fil
Semiclassical Methods for Hawking Radiation from a Vaidya Black Hole
We derive the general form of Hawking temperature for Vaidya black hole in
the tunneling pictures. This kind of black hole is regarded as the description
of a more realistic one since it's time dependent decreasing mass due to the
evaporation process. Clearly, the temperature would be time dependent as our
findings. We use the semiclassical methods, namely radial null geodesic and
complex paths methods. Both methods are found to give the same results. Then,
we discuss the possible form of corresponding entropy.Comment: REVTeX 4, 11 pages, no figures, accepted for publication in IJMPA;
v2: eq.5 is correcte
Derivation of fluid dynamics from kinetic theory with the 14--moment approximation
We review the traditional derivation of the fluid-dynamical equations from
kinetic theory according to Israel and Stewart. We show that their procedure to
close the fluid-dynamical equations of motion is not unique. Their approach
contains two approximations, the first being the so-called 14-moment
approximation to truncate the single-particle distribution function. The second
consists in the choice of equations of motion for the dissipative currents.
Israel and Stewart used the second moment of the Boltzmann equation, but this
is not the only possible choice. In fact, there are infinitely many moments of
the Boltzmann equation which can serve as equations of motion for the
dissipative currents. All resulting equations of motion have the same form, but
the transport coefficients are different in each case.Comment: 15 pages, 3 figures, typos fixed and discussions added; EPJA: Topical
issue on "Relativistic Hydro- and Thermodynamics
- …