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New knowledge and new constraints: the case of NHS Direct
Call centres have mushroomed as a new dominant paradigm for service delivery. This paper presents data from fieldwork into tele-nursing within the UK health service, NHS Direct, as ‘nursing down the phone’ can be seen as a new expression of this wider development. We argue that nursing as a category of work has not been transformed through the advent of telenursing, unlike the situation in commercial call centres. Rather tele-nursing has appeared and developed as one further specialism within the nursing medical repertoire. Furthermore, the organisation of NHS Direct, as a nurse-led and dominated service, may have permitted nurses to expand their knowledge and professional power. But we are not suggesting either an upskilling or knowledge worker thesis as two developments put pressure on nurse’s work. The first is the call centre pressures operating within NHS Direct, despite its’ non-commercial and information/referral character as a health advisory service and the presence of a discourse of transformation with management. The second is the operation of a Clinical Assessment System (CAS) that nurses are obliged to use when responding to caller/patient enquiries. Our conclusions point towards the interplay between occupational autonomy and organisational control within a new service that has not yet finalised its design for the job of a tele-nurse
Endurance of SN 2005ip after a decade: X-rays, radio, and H-alpha like SN 1988Z require long-lived pre-supernova mass loss
SN2005ip was a TypeIIn event notable for its sustained strong interaction
with circumstellar material (CSM), coronal emission lines, and IR excess,
interpreted as shock interaction with the very dense and clumpy wind of an
extreme red supergiant. We present a series of late-time spectra of SN2005ip
and a first radio detection of this SN, plus late-time X-rays, all of which
indicate that its CSM interaction is still strong a decade post-explosion. We
also present and discuss new spectra of geriatric SNe with continued CSM
interaction: SN1988Z, SN1993J, and SN1998S. From 3-10 yr post-explosion,
SN2005ip's H-alpha luminosity and other observed characteristics were nearly
identical to those of the radio-luminous SN1988Z, and much more luminous than
SNe1993J and 1998S. At 10 yr after explosion, SN2005ip showed a drop in
H luminosity, followed by a quick resurgence over several months. We
interpret this variability as ejecta crashing into a dense shell located at
around 0.05 pc from the star, which may be the same shell that caused the IR
echo at earlier epochs. The extreme H-alpha luminosities in SN2005ip and
SN1988Z are still dominated by the forward shock at 10 yr post-explosion,
whereas SN1993J and SN1998S are dominated by the reverse shock at a similar
age. Continuous strong CSM interaction in SNe~2005ip and 1988Z is indicative of
enhanced mass loss for about 1e3 yr before core collapse, longer than Ne, O, or
Si burning phases. Instead, the episodic mass loss must extend back through C
burning and perhaps even part of He burning.Comment: 14 pages, 8 figs. accepted in MNRA
Metals, dust and the cosmic microwave background: fragmentation of high-redshift star-forming clouds
We investigate the effects of the Cosmic Microwave Background (CMB) radiation
field on the collapse of prestellar clouds. Using a semi-analytic model to
follow the thermal evolution of clouds with varying initial metallicities and
dust contents at different redshifts, we study self-consistently the response
of the mean Jeans mass at cloud fragmentation to metal line-cooling,
dust-cooling and the CMB. In the absence of dust grains, at redshifts z < 10
moderate characteristic masses (of 10s of Msun) are formed when the metallicity
is 10^{-4} Zsun < Z < 10^{-2.5} Zsun; at higher metallicities, the CMB inhibits
fragmentation and only very large masses (of ~ 100s of Msun) are formed. These
effects become even more dramatic at z > 10 and the fragmentation mass scales
are always > 100s of Msun, independent of the initial metallicity. When dust
grains are present, sub-solar mass fragments are formed at any redshift for
metallicities Z > 10^{-6} Zsun because dust-cooling remains relatively
insensitive to the presence of the CMB. When Z > 10^{-3} Zsun, heating of dust
grains by the CMB at z > 5 favors the formation of larger masses, which become
super-solar when Z > 10^{-2} Zsun and z > 10. Finally, we discuss the
implications of our result for the interpretation of the observed abundance
patterns of very metal-poor stars in the galactic halo.Comment: 9 pages, 5 figures, MNRAS, accepte
An accurate low-redshift measurement of the cosmic neutral hydrogen density
Using a spectral stacking technique, we measure the neutral hydrogen (HI)
properties of a sample of galaxies at across 35 pointings of the
Westerbork Synthesis Radio Telescope (WSRT). The radio data contains 1,895
galaxies with redshifts and positions known from the Sloan Digital Sky Survey
(SDSS). We carefully quantified the effects of sample bias, aperture used to
extract spectra, sidelobes and weighting technique and use our data to provide
a new estimate for the cosmic HI mass density. We find a cosmic HI mass density
of at , consistent with measurements from blind HI surveys and other
HI stacking experiments at low redshifts. The combination of the small
interferometer beam size and the large survey volume makes our result highly
robust against systematic effects due to confusion at small scales and cosmic
variance at large scales. Splitting into three sub-samples with = 0.038, 0.067 and 0.093 shows no significant evolution of the HI gas
content at low redshift.Comment: 17 pages, 24 figure
Thermoresponsive polymer micropatterns fabricated by dip-pen nanolithography for a highly controllable substrate with potential cellular applications
We report a novel approach for patterning thermoresponsive hydrogels based on N,N-diethylacrylamide (DEAAm) and bifunctional Jeffamine ED-600 by dip-pen nanolithography (DPN). The direct writing of micron-sized thermoresponsive polymer spots was achieved with efficient control over feature size. A Jeffamine-based ink prepared through the combination of organic polymers, such as DEAAm, in an inorganic silica network was used to print thermosensitive arrays on a thiol-silanised silicon oxide substrate. The use of a Jeffamine hydrogel, acting as a carrier matrix, allowed a reduction in the evaporation of ink molecules with high volatility, such as DEAAm, and facilitated the transfer of ink from tip to substrate. The thermoresponsive behaviour of polymer arrays which swell/de-swell in aqueous solution in response to a change in temperature was successfully characterised by atomic force microscopy (AFM) and Raman spectroscopy: a thermally-induced change in height and hydration state was observed, respectively. Finally, we demonstrate that cells can adhere to and interact with these dynamic features and exhibit a change in behaviour when cultured on the substrates above and below the transition temperature of the Jeffamine/DEAAm thermoresponsive hydrogels. This demonstrates the potential of these micropatterned hydrogels to act as a controllable surface for cell growth
Design and analysis considerations in the Ebola_Tx trial evaluating convalescent plasma in the treatment of Ebola virus disease in Guinea during the 2014-2015 outbreak.
The Ebola virus disease outbreak in 2014-2015 led to a huge caseload with a high case fatality rate. No specific treatments were available beyond supportive care for conditions such as dehydration and shock. Evaluation of treatment with convalescent plasma from Ebola survivors was identified as a priority. We evaluated this intervention in an emergency setting, where randomization was unacceptable. The original trial design was an open-label study comparing patients receiving convalescent plasma and supportive care to patients receiving supportive care alone. The comparison group comprised patients recruited at the start of the trial before convalescent plasma became available, as well as patients presenting during the trial for whom there was insufficient blood group-compatible plasma or no staffing capacity to provide additional transfusions. However, during the trial, convalescent plasma was available to treat all new patients. The design was changed to use a comparator group comprising patients previously treated at the same Ebola treatment center prior to the start of the trial. In the analysis, it was planned to adjust for any differences in prognostic variables between intervention and comparison groups, specifically baseline polymerase chain reaction cycle threshold and age. In addition, adjustment was planned for other potential confounders, identified in the analysis, such as patient presenting symptoms and time to treatment seeking. Because plasma treatment started up to 3 days after diagnosis and we could not define a similar time-point for the comparator group, patients who died before the third day after confirmation of diagnosis were excluded from both intervention and comparison groups in a per-protocol analysis. Some patients received additional experimental treatments soon after plasma treatment, and these were excluded. We also analyzed mortality including all patients from the time of confirmed diagnosis, irrespective of whether those in the trial series actually received plasma, as an intention-to-treat analysis. Per-protocol and intention-to-treat approaches gave similar conclusions. An important caveat in the interpretation of the findings is that it is unlikely that all potential sources of confounding, such as any variation in supportive care over time, were eliminated. Protocols and electronic data capture systems have now been extensively field-tested for emergency evaluation of treatment with convalescent plasma. Ongoing studies seek to quantify the level of neutralizing antibodies in different plasma donations to determine whether this influences the response and survival of treated patients
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