7,067 research outputs found
Clinical stakeholders' opinions on the use of selective decontamination of the digestive tract in critically ill patients in intensive care units : an international Delphi study
Peer reviewedPublisher PD
1E161348-5055 in the Supernova Remnant RCW 103: A Magnetar in a Young Low Mass Binary System?
We suggest that the unique X-ray source 1E161348-5055 at the centre of the
supernova remnant RCW 103 consists of a neutron star in close orbit with a low
mass main sequence star. The time signature of 6.67 hr is interpreted as the
neutron star's spin period. This requires the neutron star to be endowed with a
high surface magnetic field of~10^15 G. Magnetic or/and material (propeller)
torques are able to spin rapidly the young neutron star down to an asymptotic,
equilibrium spin period in close synchronism with the orbital period, similarly
to what happens in the Polar Cataclysmic Variables. 1E161348-5055 could be the
first case of a magnetar born in a young low mass binary system.Comment: Accepted for publication in the Ap
Primary care management for optimized antithrombotic treatment [PICANT]: study protocol for a cluster-randomized controlled trial
Background: Antithrombotic treatment is a continuous therapy that is often performed in general practice and requires careful safety management. The aim of this study is to investigate whether a best practice model that applies major elements of case management, including patient education, can improve antithrombotic management in primary health care in terms of reducing major thromboembolic and bleeding events.
Methods: This 24-month cluster-randomized trial will be performed in 690 adult patients from 46 practices. The trial intervention will be a complex intervention involving general practitioners, health care assistants and patients with an indication for oral anticoagulation. To assess adherence to medication and symptoms in patients, as well as to detect complications early, health care assistants will be trained in case management and will use the Coagulation-Monitoring-List (Co-MoL) to regularly monitor patients. Patients will receive information (leaflets and a video), treatment monitoring via the Co-MoL and be motivated to perform self-management. Patients in the control group will continue to receive treatment-as-usual from their general practitioners. The primary endpoint is the combined endpoint of all thromboembolic events requiring hospitalization, and all major bleeding complications. Secondary endpoints are mortality, hospitalization, strokes, major bleeding and thromboembolic complications, severe treatment interactions, the number of adverse events, quality of anticoagulation, health-related quality of life and costs. Further secondary objectives will be investigated to explain the mechanism by which the intervention is effective: patients' assessment of chronic illness care, self-reported adherence to medication, general practitioners' and health care assistants' knowledge, patients' knowledge and satisfaction with shared decision making. Practice recruitment is expected to take place between July and December 2012. Recruitment of eligible patients will start in July 2012. Assessment will occur at three time points: baseline (T0), follow-up after 12 (T1) and after 24 months (T2).
Discussion: The efficacy and effectiveness of individual elements of the intervention, such as antithrombotic interventions, self-management concepts in orally anticoagulated patients and the methodological tool, case-management, have already been extensively demonstrated. This project foresees the combination of several proven instruments, as a result of which we expect to profit from a reduction in the major complications associated with antithrombotic treatment
Driven low density granular mixtures
We study the steady state properties of a 2D granular mixture in the presence
of energy driving by employing simple analytical estimates and Direct
Simulation Monte Carlo. We adopt two different driving mechanisms: a) a
homogeneous heat bath with friction and b) a vibrating boundary (thermal or
harmonic) in the presence of gravity. The main findings are: the appearance of
two different granular temperatures, one for each species; the existence of
overpopulated tails in the velocity distribution functions and of non trivial
spatial correlations indicating the spontaneous formation of cluster
aggregates. In the case of a fluid subject to gravity and to a vibrating
boundary, both densities and temperatures display non uniform profiles along
the direction normal to the wall, in particular the temperature profiles are
different for the two species while the temperature ratio is almost constant
with the height. Finally, we obtained the velocity distributions at different
heights and verified the non gaussianity of the resulting distributions.Comment: 19 pages, 12 figures, submitted for publicatio
Geological imprint of methane seepage on the seabed and biota of the convergent Hikurangi Margin, New Zealand: box core and grab carbonate results
Short box cores (to 30 cm bsf) and seafloor carbonate grab samples were acquired at mapped hydrocarbon seep sites (600–1200 m water depths) during the 2007 RV SONNE SO191 cruise on the Hikurangi Margin offshore eastern North Island, New Zealand, to evaluate the influence of methane seepage on sedimentologic, biotic, mineralogic and stable isotopic attributes of seabed sediments. Sedimentary horizons in the box cores consist of siliciclastic silts and sands, shell beds and nodular, microcrystalline aragonite bands up to 15 cm thick. The megafauna is dominated by infaunal to semi-infaunal chemosymbiotic bivalves (Calyptogena, Lucinoma, and Acharax), as well as associated worms and carnivorous and grazing gastropods. Burrows in silts, some occupied by worms or juvenile Acharax, mainly have simple morphologies more typical of high-energy, nearshore settings than deep-sea environments, while a few are large and sparsely branched with wall scratch marks inferred to be of decapod crustacean origin.
The box core silts and nodular carbonate samples vary in TOC content from 0.2 to 0.9 wt.%, carbonate content from 4 to 78%, and δ13C and δ18O values from − 50.3 to − 0.6‰ PDB and + 0.77 to + 3.2‰ PDB, respectively. Low carbonate content silt samples have the most enriched δ13C values, implying a seawater source for their pore water bicarbonate. Negative δ13C and positive δ18O values typify the nodular, microcrystalline aragonite bands, indicating formation during microbially mediated, sulphate-dependent anaerobic oxidation of methane (AOM) in a cold, near-seafloor environment, as is also supported by lipid biomarker data. A clear isotopic mixing trend of decreasing δ13C and increasing δ18O and carbonate content in the fine (< 100 µm) carbonate fraction of the host silts also has been reported from other methane seep provinces, and suggests a heterogeneous influx of methane-rich see
Probing the low transverse momentum domain of Z production with novel variables
The measurement of the low transverse momentum region of vector boson
production in Drell-Yan processes has long been invaluable to testing our
knowledge of QCD dynamics both beyond fixed-order in perturbation theory as
well as in the non-perturbative region. Recently the D\O\ collaboration have
introduced novel variables which lead to improved measurements compared to the
case of the standard QT variable. To complement this improvement on the
experimental side, we develop here a complete phenomenological study dedicated
in particular to the new \phi* variable. We compare our study, which contains
the state-of-the-art next-to-next-to-leading resummation of large logarithms
and a smooth matching to the full next-to-leading order result, to the
experimental data and find excellent agreement over essentially the entire
range of \phi*, even without direct inclusion of non-perturbative effects. We
comment on our findings and on the potential for future studies to constrain
non-perturbative behaviour.Comment: 20 pages, 7 figures. Version accepted for publication in JHEP. A
figure with comparison to RESBOS has been adde
Steady state properties of a mean field model of driven inelastic mixtures
We investigate a Maxwell model of inelastic granular mixture under the
influence of a stochastic driving and obtain its steady state properties in the
context of classical kinetic theory. The model is studied analytically by
computing the moments up to the eighth order and approximating the
distributions by means of a Sonine polynomial expansion method. The main
findings concern the existence of two different granular temperatures, one for
each species, and the characterization of the distribution functions, whose
tails are in general more populated than those of an elastic system. These
analytical results are tested against Monte Carlo numerical simulations of the
model and are in general in good agreement. The simulations, however, reveal
the presence of pronounced non-gaussian tails in the case of an infinite
temperature bath, which are not well reproduced by the Sonine method.Comment: 23 pages, 10 figures, submitted for publicatio
NLL+NNLO predictions for jet-veto efficiencies in Higgs-boson and Drell-Yan production
Using the technology of the CAESAR approach to resummation, we examine the
jet-veto efficiency in Higgs-boson and Drell-Yan production at hadron colliders
and show that at next-to-leading logarithmic (NLL) accuracy the resummation
reduces to just a Sudakov form factor. Matching with NNLO calculations results
in stable predictions for the case of Drell-Yan production, but reveals
substantial uncertainties in gluon-fusion Higgs production, connected in part
with the poor behaviour of the perturbative series for the total cross section.
We compare our results to those from POWHEG with and without reweighting by
HqT, as used experimentally, and observe acceptable agreement. In an appendix
we derive the part of the NNLL resummation corrections associated with the
radius dependence of the jet algorithm.Comment: 30 pages, 8 figures; v2 as published in JHE
Altered hippocampal morphology in unmedicated patients with major depressive illness
Despite converging evidence that major depressive illness is associated with both memory impairment and hippocampal pathology, findings vary widely across studies and it is not known whether these changes are regionally specific. In the present study we acquired brain MRIs (magnetic resonance images) from 31 unmedicated patients with MDD (major depressive disorder; mean age 39.2±11.9 years; 77% female) and 31 demographically comparable controls. Three-dimensional parametric mesh models were created to examine localized alterations of hippocampal morphology. Although global volumes did not differ between groups, statistical mapping results revealed that in MDD patients, more severe depressive symptoms were associated with greater left hippocampal atrophy, particularly in CA1 (cornu ammonis 1) subfields and the subiculum. However, previous treatment with atypical antipsychotics was associated with a trend towards larger left hippocampal volume. Our findings suggest effects of illness severity on hippocampal size, as well as a possible effect of past history of atypical antipsychotic treatment, which may reflect prolonged neuroprotective effects. This possibility awaits confirmation in longitudinal studies
The first reptilian allergen and major allergen for fish-allergic patients: Crocodile β-parvalbumin
Background: Clinical cross-reactivity between bony fish, cartilaginous fish, frog, and chicken muscle has previously been demonstrated in fish-allergic patients. In indicative studies, two reports of anaphylaxis following the consumption of crocodile meat and IgE-cross-binding were linked to the major fish allergen parvalbumin (PV). This study investigates IgE-binding proteins in crocodile meat with a focus on PV and their clinical relevance.
Methods: Proteins were extracted from muscle tissue of crocodile, three bony fish, and two cartilaginous fish. A cohort of fish-allergic pediatric patients (n = 77) underwent allergen skin prick testing (SPT) to three fish preparations (n = 77) and crocodile (n = 12). IgE-binding proteins were identified and quantified by SDS-PAGE, mass spectrometric analyses, and immunoblotting using commercial and in-house antibodies, as well as individual and pooled patients’ serum. PV isoforms were purified or recombinantly expressed before immunological analyses, including human mast cell degranulation assay.
Results: Of the tissues analyzed, PV was most abundant in heated crocodile preparation, triggering an SPT of ≥3 mm in 8 of 12 (67%) fish-allergic patients. Seventy percent (31 of 44) of fish PV-sensitized patients demonstrated IgE-binding to crocodile PV. Crocodile β-PV was the major IgE-binding protein but 20-fold less abundant than α-PV. Cellular reactivity was demonstrated for β-PV and epitopes predicted, explaining frequent IgE-cross-binding of β-PVs. Both PV isoforms are now registered as the first reptile allergens with the WHO/IUIS (β-PV as Cro p 1 and α-PV as Cro p 2).
Conclusion: Fish-allergic individuals may be at risk of an allergy to crocodile and should seek specialist advice before consuming crocodilian meat
- …