2,893 research outputs found
The views of doctors in their first year of medical practice on the lasting impact of a preparation for house officer course they undertook as final year medical students
<p>Abstract</p> <p>Background</p> <p>The UK General Medical Council recommends that medical students have the opportunity of shadowing the outgoing new doctor whose post they will soon undertake. At the University of Nottingham the two-week shadowing period was preceded by two weeks of lectures/seminars wherein students followed sessions on topics such as common medical/surgical emergencies, contracts, time management, surviving the first two years of clinical practice, careers advice and so on.</p> <p>The present study aimed to gain a better knowledge and understanding of the lasting impact of a four-week preparation course for new Foundation Year 1 doctors [F1 s - interns]. The objectives chosen to achieve this aim were:</p> <p>1/ to determine the extent to which the lecture/seminar course and shadowing period achieved their stated aim of smoothing the transition from life as a medical student to work as a new doctor;</p> <p>2/ to evaluate perceptions of the importance of various forms of knowledge in easing the transition between medical student and new doctor</p> <p>Method</p> <p>In the spring of 2007, 90 graduates from Nottingham were randomly selected and then emailed a link to a short, online survey of quantitative and qualitative questions. Of these 76 responded. Analysis of quantitative data was carried out using SPSS 16.0 and employed McNemar's test. Analysis of the qualitative data was carried out using the constant comparative method.</p> <p>Results</p> <p>Only 31% of respondents strongly agreed or agreed that the lecture/seminar part of the course prepared them well for their first FY1 post; 14% agreed that during their first job they drew on the knowledge gained during the lecture/seminar course; 94% strongly agreed or agreed that the shadowing part of the course was more useful than the lecture/seminar part.</p> <p>Experiential knowledge gained in the shadowing was the most highly valued, followed by procedural knowledge with propositional knowledge coming far behind.</p> <p>Conclusions</p> <p>Our study shows that new doctors retrospectively value most the knowledge they are able to transfer to the workplace and value least material which seems to repeat what they had learned for their final exams.</p
A Search for Intrinsic Polarization in O Stars with Variable Winds
New observations of 9 of the brightest northern O stars have been made with
the Breger polarimeter on the 0.9~m telescope at McDonald Observatory and the
AnyPol polarimeter on the 0.4~m telescope at Limber Observatory, using the
Johnson-Cousins UBVRI broadband filter system. Comparison with earlier
measurements shows no clearly defined long-term polarization variability. For
all 9 stars the wavelength dependence of the degree of polarization in the
optical range can be fit by a normal interstellar polarization law. The
polarization position angles are practically constant with wavelength and are
consistent with those of neighboring stars. Thus the simplest conclusion is
that the polarization of all the program stars is primarily interstellar.
The O stars chosen for this study are generally known from ultraviolet and
optical spectroscopy to have substantial mass loss rates and variable winds, as
well as occasional circumstellar emission. Their lack of intrinsic polarization
in comparison with the similar Be stars may be explained by the dominance of
radiation as a wind driving force due to higher luminosity, which results in
lower density and less rotational flattening in the electron scattering inner
envelopes where the polarization is produced. However, time series of
polarization measurements taken simultaneously with H-alpha and UV spectroscopy
during several coordinated multiwavelength campaigns suggest two cases of
possible small-amplitude, periodic short-term polarization variability, and
therefore intrinsic polarization, which may be correlated with the more widely
recognized spectroscopic variations.Comment: LaTeX2e, 22 pages including 11 tables; 12 separate gif figures; uses
aastex.cls preprint package; accepted by The Astronomical Journa
The Magnetorotational Instability in Core Collapse Supernova Explosions
We investigate the action of the magnetorotational instability (MRI) in the
context of iron-core collapse. Exponential growth of the field on the rotation
time scale by the MRI will dominate the linear growth process of field line
"wrapping" with the same characteristic time. We examine a variety of initial
rotation states, with solid body rotation or a gradient in rotational velocity,
that correspond to models in the literature. A relatively modest value of the
initial rotation, a period of ~ 10 s, will give a very rapidly rotating PNS and
hence strong differential rotation with respect to the infalling matter. We
assume conservation of angular momentum on spherical shells. Results are
discussed for two examples of saturation fields, a fiducial field that
corresponds to Alfven velocity = rotational velocity and a field that
corresponds to the maximum growing mode of the MRI. Modest initial rotation
velocities of the iron core result in sub-Keplerian rotation and a
sub-equipartition magnetic field that nevertheless produce substantial MHD
luminosity and hoop stresses: saturation fields of order 10^{15} - 10^{16} G
develop within 300 msec after bounce with an associated MHD luminosity of about
10^{52} erg/s. Bi-polar flows driven by this MHD power can affect or even cause
the explosions associated with core-collapse supernovae.Comment: 42 pages, including 15 figures. Accepted for publication in ApJ. We
have revised to include an improved treatment of the convection, and some
figures have been update
The reversal characteristics of GABAergic neurons: a neurovascular model
Neurovascular coupling (NVC) is the ability to locally adjust vascular resistance as a function of neuronal activity. Recent experiments have illustrated that NVC is partially independent of metabolic signals. In addition, nitric oxide (NO) has been shown in some instances to provide an important mechanism in altering vascular resistance. An extension to the original model of NVC [1] has been developed to include the activation of both somatosensory neurons and GABAergic interneurons and to investigate the role of NO and the delicate balance of GABA and neuronal peptide enzymes (NPY) pathways. The numerical model is compared to murine experimental data that provides time-dependent profiles of oxy, de-oxy, and total-hemoglobin. The results indicate a delicate balance that exists between GABA and NPY when nNOS interneurons are activated mediated by NO. Whereas somatosensory neurons (producing potassium into the extracellular space) do not seem to be effected by the inhibition of NO. Further work will need to be done to investigate the role of NO when stimulation periods are increased substantially from the short pulses of 2âs as used in the above experiments
MOST detects corotating bright spots on the mid-O type giant {\xi} Persei
We have used the MOST (Microvariability and Oscillations of STars)
microsatellite to obtain four weeks of contiguous high-precision broadband
visual photometry of the O7.5III(n)((f)) star {\xi} Persei in November 2011.
This star is well known from previous work to show prominent DACs (Discrete
Absorption Components) on time-scales of about 2 d from UV spectroscopy and NRP
(Non Radial Pulsation) with one (l = 3) p-mode oscillation with a period of 3.5
h from optical spectroscopy. Our MOST-orbit (101.4 min) binned photometry fails
to reveal any periodic light variations above the 0.1 mmag 3-sigma noise level
for periods of hours, while several prominent Fourier peaks emerge at the 1
mmag level in the two-day period range. These longer-period variations are
unlikely due to pulsations, including gravity modes. From our simulations based
upon a simple spot model, we deduce that we are seeing the photometric
modulation of several co-rotating bright spots on the stellar surface. In our
model, the starting times (random) and lifetimes (up to several rotations) vary
from one spot to another yet all spots rotate at the same period of 4.18 d, the
best-estimated rotation period of the star. This is the first convincing
reported case of co-rotating bright spots on an O star, with important
implications for drivers of the DACs (resulting from CIRs - Corotating
Interaction Regions) with possible bright-spot generation via a breakout at the
surface of a global magnetic field generated by a subsurface convection zone.Comment: 9 pages, 4 figures, 2 tables, MNRAS in pres
Why do only some people who support parties actually join them? Evidence from Britain
What makes people join a political party is one of the most commonly studied questions in research on party members. Nearly all this research, however, is based on talking to people who have actually joined parties. This article simultaneously analyses surveys of members of political parties in Britain and surveys of non-member supporters of those same parties. This uniquely enables us to model the decision to join parties. The results suggest that most of the elements that constitute the influential âGeneral Incentives Modelâ are significant. But it also reveals that, while party supporters imagine that selective benefits, social norms and opposing rival partiesâ policies are key factors in membersâ decisions to join a party, those who actually do so are more likely to say they are motivated by attachments to their partyâs values, policies and leaders, as well as by an altruistic desire to support democracy more generally
The effect of acid treatment on the surface chemistry and topography of graphite
Highly oriented pyrolytic graphite (HOPG) samples were investigated as model catalyst supports. The surfaces were treated with dilute HCl and HNO3 under ambient conditions and examined with atomic force microscopy and scanning tunnelling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). Raised features were formed on the HOPG surface after acid treatment. These protrusions were typically 4â6 nm in height and between 10 and 100 nm in width, covering 5â20% of the substrate for acid concentrations between 0.01 and 0.2 M. Both width and surface density of the features increases with acid concentration but the heights are not affected. STM images show that the graphite lattice extends over the protrusions indicating that the features are âblistersâ on the surface rather than deposited material, a view that is supported by the XPS which shows no other significant adsorbates except for oxygen in the case of the nitric acid. We propose that penetration of the acid at defective sites leads to a decrease in the interplanar van der Waals forces and a local delamination similar to the âbubblesâ reported between exfoliated graphene sheets and a substrate. These findings are important in the context of understanding how carbon supports stabilise active components in heterogeneous catalysts
The implications of carbon dioxide and methane exchange for the heavy mitigation RCP2.6 scenario under two metrics
Greenhouse gas emissions associated with Representative Concentration Pathway RCP2.6 could limit global warming to around or below a 2 °C increase since pre-industrial times. However this scenario implies very large and rapid reductions in both carbon dioxide (CO2) and non-CO2 emissions, and suggests a need to understand available flexibility between how different greenhouse gases might be abated. There is a growing interest in developing a greater understanding of the particular role of shorter lived non-CO2 gases as abatement options. We address this here through a sensitivity study of different methane (CH4) emissions pathways to year 2100 and beyond, by including exchanges with CO2 emissions, and with a focus on related climate and economic advantages and disadvantages.
Metrics exist that characterise gas equivalence in terms of climate change effect per tonne emitted. We analyse the implications of CO2 and CH4 emission exchanges under two commonly considered metrics: the 100-yr Global Warming Potential (GWP-100) and Global Temperature Potential (GTP-100). This is whilst keeping CO2-equivalent emissions pathways fixed, based on the standard set of emissions usually associated with RCP2.6. An idealised situation of anthropogenic CH4 emissions being reduced to zero across a period of two decades and with the implementation of such cuts starting almost immediately gives lower warming than for standard RCP2.6 emissions during the 21st and 22nd Century. This is despite exchanging for higher CO2 emissions. Introducing Marginal Abatement Cost (MAC) curves provides an economic assessment of alternative gas reduction strategies. Whilst simpler than utilising full Integrated Assessment Models (IAMs), MAC curves are more transparent for illustrative modelling. The GWP-100 metric places a relatively high value on climate change prevented for methane emission reduction, as compared to an equivalent mass of CO2 reduction. This in combination with the strong non-linearity in MAC curves (moving quickly from relatively cheap removal to emissions difficult to cut at any cost) causes little change under cost minimisation from standard RCP2.6 emissions. This reflects the original development of RCP2.6 standard emissions from similar minimisation. With gas exchange under GTP-100, however, we find much less methane is abated, resulting in higher temperatures, whilst costs are slightly lower.
Our results also highlight the point at which greater methane mitigation would become beneficial from both a climate and economic aspect. If by 2030 removal of all methane were to become possible at an average cost less than $1000 per tonne of CH4, then this would be the cheapest option, for GWP-100 metric and our CO2 MAC curve. Critically this would increase the possibility of constraining warming to two degrees
The politics of antagonism
In perhaps the last piece completed before his sudden death in April 2014 ErnestoLaclau returned to the concept of antagonism (Laclau, 2015, pp. 101â125). Itsconceptual origins lie in his immanent critique of, and break with, Marxism in the1970s. Laclau concluded that antagonism points to the limits of social objectivity andlinked this to an original political ontology (see Hansen, 2016 and Marchart, 2016).The development of this concept is, in effect, the story of Laclauâs theoreticaljourney. In tracking this conceptual history I demonstrate its continued pertinence tocontemporary political theory and link it to the rethinking of representation, toidealisation in political theory, and to the understanding of anti-austerity politics
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