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The nurses that roared: nurses from history who found their voices and challenged the status quo
In this article we explore how nurses from history challenged norms of nursing and society, and consider how they can influence and inspire nurses today. We discuss the role of nurses in the fight for women’s suffrage, campaigning for the vote and caring for women who suffered in their fight to achieve it, and present examples of outstanding bravery in the past and present day. The article contains examples of the bravery of some relatively unknown nurses in wartime, who also fought for equality and inclusion, and nurses who challenged the care of marginalised groups, campaigning for improved treatment, sometimes at great personal cost. Finally we consider the courage of present-day nurses. Drawing on the global campaign of “Nursing Now”, we suggest that learning from these exceptional nurses and acknowledging and highlighting their contribution can inspire us to strengthen and promote nursing and to empower women globally
A point mass in an isotropic universe: III. The region
McVittie's solution of Einstein's field equations, representing a point mass
embedded into an isotropic universe, possesses a scalar curvature singularity
at proper radius . The singularity is space-like and precedes, in the
expanding case, all other events in the space-time. It is shown here that this
singularity is gravitationally weak, and the possible structure of the region
is investigated. A characterization of this solution which does not
involve asymptotics is given.Comment: Revtex, 11pp. To appear in Class.Quant.Grav. Paper II appeared as
Class. Quant. Grav. 16 (1999) 122
Odd-parity perturbations of self-similar Vaidya spacetime
We carry out an analytic study of odd-parity perturbations of the
self-similar Vaidya space-times that admit a naked singularity. It is found
that an initially finite perturbation remains finite at the Cauchy horizon.
This holds not only for the gauge invariant metric and matter perturbation, but
also for all the gauge invariant perturbed Weyl curvature scalars, including
the gravitational radiation scalars. In each case, `finiteness' refers to
Sobolev norms of scalar quantities on naturally occurring spacelike
hypersurfaces, as well as pointwise values of these quantities.Comment: 28 page
Expansion-induced contribution to the precession of binary orbits
We point out the existence of new effects of global spacetime expansion on
local binary systems. In addition to a possible change of orbital size, there
is a contribution to the precession of elliptic orbits, to be added to the
well-known general relativistic effect in static spacetimes, and the
eccentricity can change. Our model calculations are done using geodesics in a
McVittie metric, representing a localized system in an asymptotically
Robertson-Walker spacetime; we give a few numerical estimates for that case,
and indicate ways in which the model should be improved.Comment: revtex, 7 pages, no figures; revised for publication in Classical and
Quantum Gravity, with minor changes in response to referees' comment
Chrysotile biopersistence in the lungs of persons in the general population and exposed workers.
Lung burden analysis was performed on 126 autopsy cases of persons who died in New York City from 1966 through 1968. Of the 126 cases, 107 were probably non-occupationally exposed, judging by occupational history and asbestos body content of lung. Fifty-three of the 107 cases contained short chrysotile fibers/fibrils, < 5 microns in length, present in 3-fold greater amounts than were found in laboratory background controls. The fiber concentrations ranged from 1.8 to 15.7 x 10(6) f/gm/dry lung tissue, and the proportion of fibers > or = 5 microns in length was only 0.34% of the total chrysotile population found. Other inorganic particles present included fragments of amphiboles. In contrast to these data, the lung parenchyma of persons occupationally exposed to asbestos commonly showed the presence of other fiber types, especially amosite and crocidolite, at very much higher concentrations and greater fiber length. Any chrysotile present would usually be in fiber bundle form, with both fibers and fibrils > 5 microns in length. Comparison of the lung fiber content of occupationally exposed persons with that of the general population showed marked qualitative and quantitative differences. Fibers are durable, and are retained in a range of concentrations. Their length and dose, among other factors, which control their biological potential are different in the two populations; the risk factors for chrysotile-induced disease are not the same
The Gamma Ray Pulsar Population
We apply a likelihood analysis to pulsar detections, pulsar upper limits, and
diffuse background measurements from the OSSE and EGRET instruments on the
Compton Gamma Ray Observatory to constrain the luminosity law for gamma-ray
pulsars and some properties of the gamma-ray pulsar population. We find that
the dependence of luminosity on spin period and dipole magnetic field is much
steeper at OSSE than at EGRET energies (50-200 keV and >100 MeV, respectively),
suggesting that different emission mechanisms are responsible for low- and
high-energy gamma-ray emission. Incorporating a spin-down model and assuming a
pulsar spatial distribution, we estimate the fraction of the Galactic gamma-ray
background due to unidentified pulsars and find that pulsars may be an
important component of the OSSE diffuse flux, but are most likely not important
at EGRET energies. Using measurements of the diffuse background flux from these
instruments, we are able to place constraints on the braking index, initial
spin period, and magnetic field of the Galactic pulsar population. We are also
able to constrain the pulsar birthrate to be between 1/(25 yr) and 1/(500 yr).
Our results are based on a large gamma-ray beam, but they do not scale in a
simple way with beam size. With our assumed beam size, the implied gamma-ray
efficiency for the EGRET detections is no more than 20%. We estimate that about
20 of the 169 unidentified EGRET sources are probably gamma-ray pulsars. We use
our model to predict the pulsar population that will be seen by future
gamma-ray instruments and estimate that GLAST will detect roughly 750 gamma-ray
pulsars as steady sources, only 120 of which are currently known radio pulsars.Comment: 32 pages, including figures. submitted to Ap
Does selection for growth rate in broilers affect their resistance and tolerance to Eimeria maxima?
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