155 research outputs found
Are planetary nebulae derived from multiple evolutionary scenarios?
Our understanding of planetary nebulae has been significantly enhanced as a
result of several recent large surveys (Parker et al., these proceedings).
These new discoveries suggest that the `PN phenomenon' is in fact more
heterogeneous than previously envisaged. Even after the careful elimination of
mimics from Galactic PN catalogues, there remains a surprising diversity in the
population of PNe and especially their central stars. Indeed, several
evolutionary scenarios are implicated in the formation of objects presently
catalogued as PNe. We provide a summary of these evolutionary pathways and give
examples of each. Eventually, a full census of local PNe can be used to
confront both stellar evolution theory and population synthesis models.Comment: 4 pages, 1 figure. To be published in Planetary Nebulae: an Eye to
the Future, Proceedings of IAU Symposium 283, held in Puerto de la Cruz,
Tenerife, Spain, July 25-29 201
Stress in Prefixed Disyllabic Verb/Noun Pairs
International audienceSummary of stress variation, data consistency between dictionaries, and detailed analysis of two parameters: frequency (from COCAE data) and vowel quality (full and/or reduced vowe
A microbolometer-based far infrared radiometer to study thin ice clouds in the Arctic
A far infrared radiometer (FIRR) dedicated to measuring radiation emitted by clear and cloudy atmospheres was developed in the framework of the Thin Ice Clouds in Far InfraRed Experiment (TICFIRE) technology demonstration satellite project. The FIRR detector is an array of 80 × 60 uncooled microbolometers coated with gold black to enhance the absorptivity and responsivity. A filter wheel is used to select atmospheric radiation in nine spectral bands ranging from 8 to 50 µm. Calibrated radiances are obtained using two well-calibrated blackbodies. Images are acquired at a frame rate of 120 Hz, and temporally averaged to reduce electronic noise. A complete measurement sequence takes about 120 s. With a field of view of 6°, the FIRR is not intended to be an imager. Hence spatial average is computed over 193 illuminated pixels to increase the signal-to-noise ratio and consequently the detector resolution. This results in an improvement by a factor of 5 compared to individual pixel measurements. Another threefold increase in resolution is obtained using 193 non-illuminated pixels to remove correlated electronic noise, leading an overall resolution of approximately 0.015 W m−2 sr−1. Laboratory measurements performed on well-known targets suggest an absolute accuracy close to 0.02 W m−2 sr−1, which ensures atmospheric radiance is retrieved with an accuracy better than 1 %. Preliminary in situ experiments performed from the ground in winter and in summer on clear and cloudy atmospheres are compared to radiative transfer simulations. They point out the FIRR ability to detect clouds and changes in relative humidity of a few percent in various atmospheric conditions, paving the way for the development of new algorithms dedicated to ice cloud characterization and water vapor retrieval
Multicategorial Prefixed Words Stress Behaviour: Variation and Frequency
International audienceIn-depth analysis of intra- and inter-dialectal variation, and of the role of word frequenc
Quantifying anthropogenic methane emissions and their uncertainties using very high spatial and spectral resolution satellite and airborne data
Methane is one of the most powerful greenhouse gases that has contributed to about a third of
the 2010-2019 global warming relative to the pre-industrial times in 1850-1900. The Upper Silesian
Coal Basin in southern Poland is one of the strongest anthropogenic methane (CH4) emitters in
Europe, with emissions ranging from 228 to 339 ktCH4yr-1. In that region, ventilation shafts and
drainage stations used in coal mines are the main sources of CH4 emissions, of which the mass
flows and their sources of uncertainties can be assessed using an adapted version of the
Integrated Mass Enhancement (IME) method
CO2/pH-responsive particles with built-in fluorescence read-out
yesA novel fluorescent monomer was synthesized to probe the state of CO2-responsive cross-linked polymeric particles. The fluorescent emission of this aminobromomaleimide-bearing monomer, being sensitive to protic environments, can provide information on the core hydrophilicity of the particles and therefore indicates the swollen state and size of the particles. The particles’ core, synthesized from DEAEMA (N,N-diethylaminoethyl methacrylate), is responsive to CO2 through protonation of the tertiary amines of DEAEMA. The response is reversible and the fluorescence emission can be recovered by simply bubbling nitrogen into the particle solution. Alternate purges of CO2 and N2 into the particles’ solution allow several ON/OFF fluorescence emission cycles and simultaneous particle swelling/shrinking cycles.British Petroleum Company (BP), Engineering and Physical Sciences Research Council (EPSRC
Methicillin-Susceptible ST398 Staphylococcus aureus Responsible for Bloodstream Infections: An Emerging Human-Adapted Subclone?
In the course of an annual 3-month bloodstream infections (BSI) survey conducted during a four-year period in 31 healthcare institutions located in three noncontiguous French regions, we report 18 ST398 Staphylococcus aureus BSI. ST398 BSI incidence showed a seven-fold increase during the study period (0.002 per 1,000 patient days in 2007 vs. 0.014 in 2010). ST398 BSI isolates differed from the pig-borne multiresistant clone: 17/18 BSI isolates were methicillin susceptible and none was of t011, t034 or t108 pig-borne spa-types. ST398 BSI isolates had homogenous resistance patterns (15/18 with only Eryr) and prophagic content (all harboured the hlb-converting Sau3int phage). The clustering of BSI and pig-borne isolates by spa-typing and MLVA, the occurrence of Sau3int phage in BSI isolates and the lack of this phage in pig-borne isolates suggest that the emergence of BSI isolates could have arisen from horizontal transfer, at least of the Sau3int phage, in genetically diverse MSSA ST398 isolates. The acquisition of the phage likely plays a role in the increasing ability of the lysogenic ST398 isolates to colonize human. The mode of acquisition of the non pig-borne ST398 isolates by our 18 patients remains unclear. ST398 BSI were diagnosed in patients lacking livestock exposure and were significantly associated with digestive portals of entry (3/18 [16.7%] for ST398 vs. 19/767 [2.5%] for non ST398 BSI; p = .012). This raises the question of possible foodborne human infections. We suggest the need for active surveillance to study and control the spread of this human-adapted subclone increasingly isolated in the hospital setting
CC9 Livestock-Associated Staphylococcus aureus Emerges in Bloodstream Infections in French Patients Unconnected With Animal Farming
We report 4 bloodstream infections associated with CC9 agr type II Staphylococcus aureus in individuals without animal exposure. We demonstrate, by microarray analysis, the presence of egc cluster, fnbA, cap operon, lukS, set2, set12, splE, splD, sak, epiD, and can, genomic features associated with a high virulence potential in human
Upper limits for mass and radius of objects around Proxima Cen from SPHERE/VLT
The recent discovery of an earth-like planet around Proxima Centauri has drawn much attention to this star and its environment. We performed a series of observations of Proxima Centauri using Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE), the planet-finder instrument installed at the European Southern Observatory (ESO) Very Large Telescope (VLT) UT3, using its near-infrared modules, InfraRed Dual-band Imager and Spectrograph (IRDIS) and IFS. No planet was detected directly, but we set upper limits on the mass up to 7 au by exploiting the AMES-COND models. Our IFS observations reveal that no planet more massive than ∼6–7 MJup can be present within 1 au. The dual-band imaging camera IRDIS also enables us to probe larger separations than other techniques such as radial velocity or astrometry. We obtained mass limits of the order of 4 MJup at separations of 2 au or larger, representing the most stringent mass limits at separations larger than 5 au available at the moment. We also made an attempt to estimate the radius of possible planets around Proxima using the reflected light. Since the residual noise for the observations is dominated by photon noise and thermal background, longer exposures in good observing conditions could improve the achievable contrast limit further.DM, AZ, RG, RUC, SD and ES acknowledge support from the ‘Progetti Premiali’ funding scheme of MIUR. We acknowledge support from the French ANR through the GUEPARD project grant ANR10-BLANC0504-01. QK acknowledges support from the EU through ERC grant number 279973. JH is supported by the GIPSE grant ANR-14-CE33-0018. HA acknowledges financial support by FONDECYT, grant 3150643, and support from the Millennium Science Initiative (Chilean Ministry of Economy) through grant RC130007. SPHERE was funded by ESO, with additional contributions from CNRS (France), MPIA (Germany), INAF (Italy), FINES (Switzerland) and NOVA (Netherlands). SPHERE also received funding from the European Commission Sixth and Seventh Framework Programmes as part of the Optical Infrared Coordination Network for Astronomy (OPTICON) under grant number RII3-Ct-2004-001566 for FP6 (2004-2008), grant number 226604 for FP7 (2009-2012) and grant number 312430 for FP7 (2013-2016). Part of this has been carried out within the frame of the National Centre for Competence in Research Planets supported by the Swiss National Science Foundation. H.M.S. and M.R.M. acknowledge financial support from the SNSF
PANC Study (Pancreatitis: A National Cohort Study): national cohort study examining the first 30 days from presentation of acute pancreatitis in the UK
Abstract
Background
Acute pancreatitis is a common, yet complex, emergency surgical presentation. Multiple guidelines exist and management can vary significantly. The aim of this first UK, multicentre, prospective cohort study was to assess the variation in management of acute pancreatitis to guide resource planning and optimize treatment.
Methods
All patients aged greater than or equal to 18 years presenting with acute pancreatitis, as per the Atlanta criteria, from March to April 2021 were eligible for inclusion and followed up for 30 days. Anonymized data were uploaded to a secure electronic database in line with local governance approvals.
Results
A total of 113 hospitals contributed data on 2580 patients, with an equal sex distribution and a mean age of 57 years. The aetiology was gallstones in 50.6 per cent, with idiopathic the next most common (22.4 per cent). In addition to the 7.6 per cent with a diagnosis of chronic pancreatitis, 20.1 per cent of patients had a previous episode of acute pancreatitis. One in 20 patients were classed as having severe pancreatitis, as per the Atlanta criteria. The overall mortality rate was 2.3 per cent at 30 days, but rose to one in three in the severe group. Predictors of death included male sex, increased age, and frailty; previous acute pancreatitis and gallstones as aetiologies were protective. Smoking status and body mass index did not affect death.
Conclusion
Most patients presenting with acute pancreatitis have a mild, self-limiting disease. Rates of patients with idiopathic pancreatitis are high. Recurrent attacks of pancreatitis are common, but are likely to have reduced risk of death on subsequent admissions.
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