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New Model Unions: Options for the 21st Century
The purpose of this short paper is threefold. First we discuss the underlying properties of the dominant organisational model for trade unions in Britain. Second, we look at options for changing this organisational model. Third, we conclude by looking at what this might imply for the future operation and organisation of trade unions and their engagement with their members
Patient safety in Europe: medication errors and hospital-acquired infections
The Report was commissioned by the European Federation of Nurses Associations (EFN) in November 2007 in order to support its policy statements on Patient Safety (June 2004). In that statement the EFN declares its belief that European Union health services should operate within a culture of safety that is based on working towards an open culture and the immediate reporting of mistakes; exchanging best practice and research; and lobbying for the systematic collection of information and dissemination of research findings. This Report adressess specifically the culture of highly reliable organisations using the work of James Reason (2000). Medication errors and hospital-acquired infections are examined in line with the Reprt´s parameters and a range of European studies are used as evidence. An extensive reference list is provided that allows EFN to explore work in greater detail as required
The effect of surface temperature and Reynolds number on the leeward heat-transfer for a shuttle orbiter
The effect of windward surface temperature on the heat transfer to the leeward surface of the shuttle orbiter was investigated. Heat-transfer distributions, surface-pressure distributions, and schlieren photographs were obtained for an 0.01-scale model of the 37-0 shuttle orbiter at angles-of-attack of 30 deg and of 40 deg. Similar data were obtained for a fuselage-only configuration at angles-of-attack of 30 deg and of 90 deg. Data were obtained for various Mach numbers, Reynolds numbers, and surface temperatures
Deep imaging of Eridanus II and its lone star cluster
We present deep imaging of the most distant dwarf discovered by the Dark
Energy Survey, Eridanus II (Eri II). Our Magellan/Megacam stellar photometry
reaches mag deeper than previous work, and allows us to confirm the
presence of a stellar cluster whose position is consistent with Eri II's
center. This makes Eri II, at , the least luminous galaxy known to
host a (possibly central) cluster. The cluster is partially resolved, and at
it accounts for of Eri II's luminosity. We derive
updated structural parameters for Eri II, which has a half-light radius of
pc and is elongated (), at a measured
distance of kpc. The color-magnitude diagram displays a blue,
extended horizontal branch, as well as a less populated red horizontal branch.
A central concentration of stars brighter than the old main sequence turnoff
hints at a possible intermediate-age ( Gyr) population; alternatively,
these sources could be blue straggler stars. A deep Green Bank Telescope
observation of Eri II reveals no associated atomic gas.Comment: 7 pages, 4 figures; ApJL accepte
Hunting The Most Distant Stars in the Milky Way: Methods and Initial Results
We present a new catalog of 404 M giant candidates found in the UKIRT
Infrared Deep Sky Survey (UKIDSS). The 2,400 deg available in the UKIDSS
Large Area Survey Data Release 8 resolve M giants through a volume four times
larger than that of the entire Two Micron All Sky Survey. Combining
near-infrared photometry with optical photometry and proper motions from the
Sloan Digital Sky Survey yields an M giant candidate catalog with less M dwarf
and quasar contamination than previous searches for similarly distant M giants.
Extensive follow-up spectroscopy of this sample will yield the first map of our
Galaxy's outermost reaches over a large area of sky. Our initial spectroscopic
follow-up of 30 bright candidates yielded the positive identification of
five M giants at distances kpc. Each of these confirmed M giants
have positions and velocities consistent with the Sagittarius stream. The
fainter M giant candidates in our sample have estimated photometric distances
kpc (assuming = 0.0), but require further spectroscopic
verification. The photometric distance estimates extend beyond the Milky Way's
virial radius, and increase by for each 0.5 dex decrease in assumed
. Given the number of M giant candidates, initial selection efficiency,
and volume surveyed, we loosely estimate that at least one additional
Sagittarius-like accretion event could have contributed to the hierarchical
build-up of the Milky Way's outer halo.Comment: 16 pages, 11 figures, emulateapj format. Accepted by A
Antlia B: A faint dwarf galaxy member of the NGC 3109 association
We report the discovery of Antlia B, a faint dwarf galaxy at a projected
distance of 72 kpc from NGC 3109 (15 mag), the primary
galaxy of the NGC 3109 dwarf association at the edge of the Local Group. The
tip of the red giant branch distance to Antlia B is =1.290.10 Mpc,
which is consistent with the distance to NGC 3109. A qualitative analysis
indicates the new dwarf's stellar population has both an old, metal poor red
giant branch (10 Gyr, [Fe/H]2), and a younger blue population
with an age of 200-400 Myr, analogous to the original Antlia dwarf,
another likely satellite of NGC 3109. Antlia B has \ion{H}{1} gas at a velocity
of =376 km s, confirming the association with NGC 3109
(=403 km s). The HI gas mass
(M=2.80.210 M), stellar luminosity
(=9.70.6 mag) and half light radius (=27329 pc) are
all consistent with the properties of dwarf irregular and dwarf spheroidal
galaxies in the Local Volume, and is most similar to the Leo P dwarf galaxy.
The discovery of Antlia B is the initial result from a Dark Energy Camera
survey for halo substructure and faint dwarf companions to NGC 3109 with the
goal of comparing observed substructure with expectations from the
+Cold Dark Matter model in the sub-Milky Way regime.Comment: 7 pages, 3 figures. Submitted to ApJ
Dynamical evidence for a strong tidal interaction between the Milky Way and its satellite, Leo V
We present a chemodynamical analysis of the Leo~V dwarf galaxy, based on Keck
II DEIMOS spectra of 8 member stars. We find a systemic velocity for the system
of kms, and barely resolve a
velocity dispersion for the system, with kms, consistent with previous studies of Leo~V. The
poorly resolved dispersion means we are unable to adequately constrain the dark
matter content of Leo~V. We find an average metallicity for the dwarf of
[Fe/H], and measure a significant spread in the iron abundance
of its member stars, with [Fe/H] dex, which cleanly
identifies Leo~V as a dwarf galaxy that has been able to self-enrich its
stellar population through extended star formation. Owing to the tentative
photometric evidence for tidal substructure around Leo~V, we also investigate
whether there is any evidence for tidal stripping or shocking of the system
within its dynamics. We measure a significant velocity gradient across the
system, of kms per
arcmin (or kms~kpc), which points almost directly
toward the Galactic centre. We argue that Leo~V is likely a dwarf on the brink
of dissolution, having just barely survived a past encounter with the centre of
the Milky Way.Comment: 14 pages, 12 figures, accepted for publication in MNRAS. Updated to
include minor revisions from referee proces
UK Trades Unions and the Problems of Collective Action
This paper looks at the financial resources of trades unions in the UK, both updating previous work and attempting to understand the management of first and second order collective action problems. First order problems refer to the problems of initiating collective action and second order problems refer to the management of collective action organisations. Unions are ‘cost disease’ organisations in which expenditure outstrips inflation but revenue may not. Their economic model cannot survive without some form of external subsidy. Both aggregate and case study data – from the largest UK union, Unite – are presented to illustrate the cost disease problem and to suggest options for its management
The Most Distant Stars in the Milky Way
We report on the discovery of the most distant Milky Way (MW) stars known to
date: ULAS J001535.72015549.6 and ULAS J074417.48253233.0. These stars
were selected as M giant candidates based on their infrared and optical colors
and lack of proper motions. We spectroscopically confirmed them as outer halo
giants using the MMT/Red Channel spectrograph. Both stars have large estimated
distances, with ULAS J001535.72015549.6 at kpc and ULAS
J074417.48253233.0 at 238 64 kpc, making them the first MW stars
discovered beyond 200 kpc. ULAS J001535.72015549.6 and ULAS
J074417.48253233.0 are both moving away from the Galactic center at km s and km s, respectively. Using their
distances and kinematics, we considered possible origins such as: tidal
stripping from a dwarf galaxy, ejection from the MW's disk, or membership in an
undetected dwarf galaxy. These M giants, along with two inner halo giants that
were also confirmed during this campaign, are the first to map largely
unexplored regions of our Galaxy's outer halo.Comment: Accepted and in print by ApJL. Seven pages, 2 figure
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