335 research outputs found
AgapeZ1: a Large Amplification Microlensing Event or an Odd Variable Star Towards the Inner Bulge of M31
AgapeZ1 is the brightest and the shortest duration microlensing candidate
event found in the Agape data. It occured only 42" from the center of M31. Our
photometry shows that the half intensity duration of the event6 is 4.8 days and
at maximum brightness we measure a stellar magnitude of R=18.0 with B-R=0.80
mag color. A search on HST archives produced a single resolved star within the
projected event position error box. Its magnitude is R=22.Comment: 4 pages with 5 figure
Impact of Morbidity and Mortality Conferences on Analysis of Mortality and Critical Events in Intensive Care Practice
Background Morbidity and mortality conferences are a tool for evaluating care management, but they lack a precise format for practice in intensive care units.Objectives To evaluate the feasibility and usefulness of regular morbidity and mortality conferences specific to intensive care units for improving quality of care and patient safety. Methods For 1 year, a prospective study was conducted in an 18-bed intensive care unit. Events analyzed included deaths in the unit and 4 adverse events (unexpected cardiac arrest, unplanned extubation, reintubation within 24–48 hours after planned extubation, and readmission to the unit within 48 hours after discharge) considered potentially preventable in optimal intensive care practice. During conferences, events were collectively analyzed with the help of an external auditor to determine their severity, causality, and preventability. Results During the study period, 260 deaths and 100 adverse events involving 300 patients were analyzed. The adverse events rate was 16.6 per 1000 patient-days. Adverse events occurred more often between noon and 4 pm (P = .001).The conference consensus was that 6.1% of deaths and 36% of adverse events were preventable. Preventable deaths were associated with iatrogenesis (P = .008), human errors (P < .001), and failure of unit management factors or communication (P = .003). Three major recommendations were made concerning standardization of care or prescription and organizational management, and no similar incidents have recurred. Conclusion In addition to their educational value, regular morbidity and mortality conferences formatted for intensive care units are useful for assessing quality of care and patient safety
Genetic diversity of hepatitis B virus (HBV) in Madagascar
Hepatitis B virus (HBV) is a DNA virus belonging to Hepadnaviridae family. Chronic infection with HBV is one major risk factor of hepatic disease. In Madagascar, former studies classified the country as part of high endemic area, as HBV prevalence can reach 23% in general population. However, this prevalence differs largely between urban and rural areas and is estimated to be respectively 5% and 26%. The aims of the present study were to describe the genetic diversity of HBV strains from different regions of Madagascar, and to describe the viral gene flow throughout the country by using phylogenetic analysis. This is the first large-scale molecular and phylogenetic study analyzing HBV sequences from 28 different Malagasy areas, never sampled in the past. In this study, the most prevalent genotype/sub-genotypes was E. Migration analysis showed a gene flow from zone 3 (rural) to zone 2 (suburban) and a greater gene flow from the middle part of Madagascar to the north than to the south. It is important to study the HBV infections in Madagascar and to monitor the potential spread of this viral strain inside this country
AGAPE: a microlensing search in the direction of M31
A status report of the microlensing search by the pixel method in the direction of M31, on the 2 meter telescope at Pic du Midi is given. Pixels are stable to a level better than 0.5%. Pixel variations as small as 0.02 magnitude can clearly be detected
Variable stars towards the bulge of M31: the AGAPE catalogue
We present the AGAPE astrometric and photometric catalogue of 1579 variable
stars in a 14'x10' field centred on M31. This work is the first survey devoted
to variable stars in the bulge of M31. The R magnitudes of the objects and the
B-R colours suggest that our sample is dominated by red long-period variable
stars (LPV), with a possible overlap with Cepheid-like type II stars. Twelve
nova candidates are identified. Correlations with other catalogues suggest that
2 novae could be recurrent novae and provide possible optical counterparts for
2 supersoft X-ray sources candidates observed with Chandra.Comment: 11 pages, Latex, accepted for publication in A&
Planck intermediate results. XLI. A map of lensing-induced B-modes
The secondary cosmic microwave background (CMB) -modes stem from the
post-decoupling distortion of the polarization -modes due to the
gravitational lensing effect of large-scale structures. These lensing-induced
-modes constitute both a valuable probe of the dark matter distribution and
an important contaminant for the extraction of the primary CMB -modes from
inflation. Planck provides accurate nearly all-sky measurements of both the
polarization -modes and the integrated mass distribution via the
reconstruction of the CMB lensing potential. By combining these two data
products, we have produced an all-sky template map of the lensing-induced
-modes using a real-space algorithm that minimizes the impact of sky masks.
The cross-correlation of this template with an observed (primordial and
secondary) -mode map can be used to measure the lensing -mode power
spectrum at multipoles up to . In particular, when cross-correlating with
the -mode contribution directly derived from the Planck polarization maps,
we obtain lensing-induced -mode power spectrum measurement at a significance
level of , which agrees with the theoretical expectation derived
from the Planck best-fit CDM model. This unique nearly all-sky
secondary -mode template, which includes the lensing-induced information
from intermediate to small () angular scales, is
delivered as part of the Planck 2015 public data release. It will be
particularly useful for experiments searching for primordial -modes, such as
BICEP2/Keck Array or LiteBIRD, since it will enable an estimate to be made of
the lensing-induced contribution to the measured total CMB -modes.Comment: 20 pages, 12 figures; Accepted for publication in A&A; The B-mode map
is part of the PR2-2015 Cosmology Products; available as Lensing Products in
the Planck Legacy Archive http://pla.esac.esa.int/pla/#cosmology; and
described in the 'Explanatory Supplement'
https://wiki.cosmos.esa.int/planckpla2015/index.php/Specially_processed_maps#2015_Lensing-induced_B-mode_ma
Genetic Divergence and Dispersal of Yellow Fever Virus, Brazil
Examining viral isolates collected over 66 years shows divergence into clades and potential dispersal by human migration
Landuse and soil degradation in the southern Maya lowlands, from Pre-Classic to Post-Classic times : The case of La Joyanca (Petén, Guatemala)
International audienceThis work focuses on the impact of Maya agriculture on soil degradation. In site and out site studies in the area of the city of La Joyanca (NW Petén) show that "Maya clays" do not constitute a homogeneous unit, but represent a complex sedimentary record. A high resolution analysis leads us to document changes in rates and practices evolving in time in relation with major socio-political and economic changes. It is possible to highlight extensive agricultural practices between Early Pre-classical to Late Pre-classical times. Intensification occurs in relation with reduction of the fallow duration during Pre-classic to Classic periods. The consequences of these changes on soil erosion are discussed. However, it does not seem that the agronomic potential of the soils was significantly degraded before the end of the Classic period
Retinoic acid reduces human neuroblastoma cell migration and invasiveness: effects on DCX, LIS1, neurofilaments-68 and vimentin expression
<p>Abstract</p> <p>Background</p> <p>Neuroblastoma is a severe pediatric tumor, histologically characterised by a variety of cellular phenotypes. One of the pharmacological approaches to neuroblastoma is the treatment with retinoic acid. The mechanism of action of retinoic acid is still unclear, and the development of resistance to this differentiating agent is a great therapy problem.</p> <p>Doublecortin, a microtubule-associated protein involved in neuronal migration, has recently been proposed as a molecular marker for the detection of minimal residual disease in human neuroblastoma. Nevertheless, no information is available on the expression of doublecortin in the different cell-types composing human neuroblastoma, its correlation with neuroblastoma cell motility and invasiveness, and the possible modulations exerted by retinoic acid treatment.</p> <p>Methods</p> <p>We analysed by immunofluorescence and by Western blot analysis the presence of doublecortin, lissencephaly-1 (another protein involved in neuronal migration) and of two intermediate filaments proteins, vimentin and neurofilament-68, in SK-N-SH human neuroblastoma cell line both in control conditions and under retinoic acid treatment. Migration and cell invasiveness studies were performed by wound scratch test and a modified microchemotaxis assay, respectively.</p> <p>Results</p> <p>Doublecortin is expressed in two cell subtypes considered to be the more aggressive and that show high migration capability and invasiveness.</p> <p>Vimentin expression is excluded by these cells, while lissencephaly-1 and neurofilaments-68 are immunodetected in all the cell subtypes of the SK-N-SH cell line. Treatment with retinoic acid reduces cell migration and invasiveness, down regulates doublecortin and lissencephaly-1 expression and up regulates neurofilament-68 expression. However, some cells that escape from retinoic acid action maintain migration capability and invasiveness and express doublecortin.</p> <p>Conclusion</p> <p>a) Doublecortin is expressed in human neuroblastoma cells that show high motility and invasiveness;</p> <p>b) Retinoic acid treatment reduces migration and invasiveness of the more aggressive cell components of SK-N-SH cells;</p> <p>c) The cells that after retinoic acid exposure show migration and invasive capability may be identified on the basis of doublecortin expression.</p
- …