178 research outputs found
Cardiogenic Shock
80% of people developing shock after
myocardial infarction die. This essay is concerned to ask why they die and what can be done
about it.Accordingly it consists of two parts:
the one concerned with the definition and some
relevant aspects of the pathogenesis of cardiogenic shock; the other concerned with therapy,
its difficulties and its future
Post impact evaluation of an E-learning cross-infection control CD-ROM provided to all general dental practitioners in England
Aim To carry out a post-impact evaluation of a cross-infection control CD-ROM, developed for NHS dental teams as a continuing professional development e-learning tool. The program was commissioned by the Department of Health and developed by a project team through the UK Committee of Postgraduate Dental Deans. The Dental Practice Boardhad originally sent one copy of the CD-ROM to each dental practice in England in 2004. Method A quantitative statistical analysis of the results of 326 online respondents to the learning package and a survey of 118 dental practitioners drawn from the Dental Practice Board database. Results Practitioners felt the CD-ROM in this instance was well designed and appropriate for their needs. It is inclusive and accessible to a wide range of dental professionals including nurses and hygienists. Conclusions This form of continuing professional development is popular with dental practitioners, although it should not be the only form of continuing professional development available. However, whilst the project was generally regarded as successful, there were problems with the distribution of the CD-ROM. This suggests that anonline resource should be made available in the future
Spitzer characterisation of dust in an anomalous emission region: the Perseus cloud
Anomalous microwave emission is known to exist in the Perseus cloud. One of
the most promising candidates to explain this excess of emission is electric
dipole radiation from rapidly rotating very small dust grains, commonly
referred to as spinning dust. Photometric data obtained with the Spitzer Space
Telescope have been reprocessed and used in conjunction with the dust emission
model DUSTEM to characterise the properties of the dust within the cloud. This
analysis has allowed us to constrain spatial variations in the strength of the
interstellar radiation field (), the mass abundances of the
PAHs and VSGs relative to the BGs (Y and Y), the
column density of hydrogen (N) and the equilibrium dust
temperature (T). The parameter maps of Y,
Y and are the first of their kind to be
produced for the Perseus cloud, and we used these maps to investigate the
physical conditions in which anomalous emission is observed. We find that in
regions of anomalous emission the strength of the ISRF, and consequently the
equilibrium temperature of the dust, is enhanced while there is no significant
variation in the abundances of the PAHs and the VSGs or the column density of
hydrogen. We interpret these results as an indication that the enhancement in
might be affecting the properties of the small
stochastically heated dust grains resulting in an increase in the spinning dust
emission observed at 33 GHz. This is the first time that such an investigation
has been performed, and we believe that this type of analysis creates a new
perspective in the field of anomalous emission studies, and represents a
powerful new tool for constraining spinning dust models.Comment: 13 pages, 9 figures, accepted for publication in MNRA
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
The short term variability of the Galactic cosmic ray flux (CRF) reaching
Earth has been previously associated with variations in the global low altitude
cloud cover. This CRF variability arises from changes in the solar wind
strength. However, cosmic ray variability also arises intrinsically from
variable activity of and motion through the Milky Way. Thus, if indeed the CRF
climate connection is real, the increased CRF witnessed while crossing the
spiral arms could be responsible for a larger global cloud cover and a reduced
temperature, thereby facilitating the occurrences of ice ages. This picture has
been recently shown to be supported by various data (Shaviv, 2001). In
particular, the variable CRF recorded in Iron meteorites appears to vary
synchronously with the appearance ice ages.
Here we expand upon the original treatment with a more thorough analysis and
more supporting evidence. In particular, we discuss the cosmic ray diffusion
model which considers the motion of the Galactic spiral arms. We also elaborate
on the structure and dynamics of the Milky Way's spiral arms. In particular, we
bring forth new argumentation using HI observations which imply that the
galactic spiral arm pattern speed appears to be that which fits the glaciation
period and the cosmic-ray flux record extracted from Iron meteorites. In
addition, we show that apparent peaks in the star formation rate history, as
deduced by several authors, coincides with particularly icy epochs, while the
long period of 1 to 2 Gyr before present, during which no glaciations are known
to have occurred, coincides with a significant paucity in the past star
formation rate.Comment: 33 pages, 11 figures. To Appear in New Astronom
Developing Risk Management as a Competitive Capability
At the level of the firm, three major parameters are found to influence the ability of SMEs to develop risk management competencies; these are enterprise risk management, internal control, and risk culture
Angular Power Spectra of the Millimeter Wavelength Background Light from Dusty Star-forming Galaxies with the South Pole Telescope
We use data from the first 100 square-degree field observed by the South Pole
Telescope (SPT) in 2008 to measure the angular power spectrum of temperature
anisotropies contributed by the background of dusty star-forming galaxies
(DSFGs) at millimeter wavelengths. From the auto and cross-correlation of 150
and 220 GHz SPT maps, we significantly detect both Poisson distributed and, for
the first time at millimeter wavelengths, clustered components of power from a
background of DSFGs. The spectral indices between 150 and 220 GHz of the
Poisson and clustered components are found to be 3.86 +- 0.23 and 3.8 +- 1.3
respectively, implying a steep scaling of the dust emissivity index beta ~ 2.
The Poisson and clustered power detected in SPT, BLAST (at 600, 860, and 1200
GHz), and Spitzer (1900 GHz) data can be understood in the context of a simple
model in which all galaxies have the same graybody spectrum with dust
emissivity index of beta = 2 and dust temperature T_d = 34 K. In this model,
half of the 150 GHz background light comes from redshifts greater than 3.2. We
also use the SPT data to place an upper limit on the amplitude of the kinetic
Sunyaev-Zel'dovich power spectrum at l = 3000 of 13 uK^2 at 95% confidence.Comment: 18 pages, 9 figure
What does inflation really predict?
If the inflaton potential has multiple minima, as may be expected in, e.g.,
the string theory "landscape", inflation predicts a probability distribution
for the cosmological parameters describing spatial curvature (Omega_tot), dark
energy (rho_Lambda, w, etc.), the primordial density fluctuations (Omega_tot,
dark energy (rho_Lambda, w, etc.). We compute this multivariate probability
distribution for various classes of single-field slow-roll models, exploring
its dependence on the characteristic inflationary energy scales, the shape of
the potential V and and the choice of measure underlying the calculation. We
find that unless the characteristic scale Delta-phi on which V varies happens
to be near the Planck scale, the only aspect of V that matters observationally
is the statistical distribution of its peaks and troughs. For all energy scales
and plausible measures considered, we obtain the predictions Omega_tot ~
1+-0.00001, w=-1 and rho_Lambda in the observed ballpark but uncomfortably
high. The high energy limit predicts n_s ~ 0.96, dn_s/dlnk ~ -0.0006, r ~ 0.15
and n_t ~ -0.02, consistent with observational data and indistinguishable from
eternal phi^2-inflation. The low-energy limit predicts 5 parameters but prefers
larger Q and redder n_s than observed. We discuss the coolness problem, the
smoothness problem and the pothole paradox, which severely limit the viable
class of models and measures. Our findings bode well for detecting an
inflationary gravitational wave signature with future CMB polarization
experiments, with the arguably best-motivated single-field models favoring the
detectable level r ~ 0.03. (Abridged)Comment: Replaced to match accepted JCAP version. Improved discussion,
references. 42 pages, 17 fig
A roadmap for global synthesis of the plant tree of life
Providing science and society with an integrated, up-to-date, high quality, open, reproducible and sustainable plant tree of life would be a huge service that is now coming within reach. However, synthesizing the growing body of DNA sequence data in the public domain and disseminating the trees to a diverse audience are often not straightforward due to numerous informatics barriers. While big synthetic plant phylogenies are being built, they remain static and become quickly outdated as new data are published and tree-building methods improve. Moreover, the body of existing phylogenetic evidence is hard to navigate and access for non-experts. We propose that our community of botanists, tree builders, and informaticians should converge on a modular framework for data integration and phylogenetic analysis, allowing easy collaboration, updating, data sourcing and flexible analyses. With support from major institutions, this pipeline should be re-run at regular intervals, storing trees and their metadata long-term. Providing the trees to a diverse global audience through user-friendly front ends and application development interfaces should also be a priority. Interactive interfaces could be used to solicit user feedback and thus improve data quality and to coordinate the generation of new data. We conclude by outlining a number of steps that we suggest the scientific community should take to achieve global phylogenetic synthesis
Character, Incidence, and Predictors of Knee Pain and Activity after Infrapatellar Intramedullary Nailing of an Isolated Tibia Fracture
© Copyright 2015 Wolters Kluwer Health, Inc. All rights reserved. Objective: To study the activity and incidence of knee pain after sustaining an isolated tibia fracture treated with an infrapatellar intramedullary nail at 1 year. Design: Retrospective review of prospective cohort. Setting: Multicenter Academic and Community hospitals. Patients: Four hundred thirty-seven patients with an isolated tibia fracture completed a 12-month assessment on pain and self-reported activity. Intervention: Infrapatellar intramedullary nail. Outcomes: Demographic information, comorbid conditions, injury characteristics, and surgical technique were recorded. Knee pain was defined on a 1-7 scale with 1 being no pain and 7 being a very great deal of pain. Knee pain \u3e4 was considered clinically significant. Patients reported if they were able, able with difficulty, or unable to perform the following activities: kneel, run, climb stairs, and walk prolonged. Variables were tested in multilevel multivariable regression analyses. Results: In knee pain, 11% of patients reported a good deal to a very great deal of pain (\u3e4), and 52% of patients reported no or very little pain at 12 months. In activity at 12 months, 26% and 29% of patients were unable to kneel or run, respectively, and 31% and 35% of patients, respectively, stated they were able with difficulty or unable to use stairs or walk. Conclusions: Clinically significant knee pain (\u3e4/7) was present in 11% of patients 1 year after a tibia fracture. Of note, 31%-71% of patients had difficulty performing or were unable to perform routine daily activities of kneeling, running, and stair climbing, or walking prolonged distances
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