337 research outputs found
GRH et Genre. Les dĂ©fis de lâĂ©galitĂ© hommes-femmes Annie Cornet, Jacqueline Laufer et Sophia Belghiti-Mahut (dir.) Paris, Vuibert, coll. « AGRH », 2008
New lambda Bootis stars with a shell
We publish here the second part of our spectroscopic survey at high
dispersion of some known and suspected lambda Bootis stars with a view to
detecting circumstellar shell features. Eight stars of our sample exhibit such
features. These stars are fast rotators, a result which is in line with
Holweger and Rentzsch-Holm's study (1995). The analysis of the photometric data
has allowed us to confirm the exclusion of a few stars misclassified from the
lambda Bootis group.Comment: 13 pages, 12 figures, accepted for publication in A&A Suppl. Se
Natural Haemophilus influenzae type b capsular polysaccharide antibodies in 412 infants and children from West Africa (Burkina-Faso) and France: a cross-sectional serosurvey.
Prior to possible introduction of large-scale vaccination programmes, an estimation and comparison of naturally acquired immunity against Haemophilus influenzae type b (Hib) was carried out in two populations of age-stratified infants and children (from birth to 14 years old) in Burkina-Faso (West Africa) (n = 206) and France (n = 206). Hib capsular polysaccharide antibodies were detected by an ELISA method. The difference in the percentages of minimum protective levels for the two populations were not significant (0.15 microg/ml) for newborns (0-1 month) but became significant as early as 2 to 3 months of age (p < 0.01) when lower levels were found among infants from Burkina-Faso. Subsequently, the percentages in both countries remained low until 11 months of age and showed no significant differences. For children between 12 and 35 months, the results > or = 0.15 microg/ml were significantly higher in France (p < or = 0.05). From 36 months, the percentage of minimum seropositivity increased in Burkina-Faso, so that the difference was no longer significant. In each country, the percentage of children with the minimum protective level varied significantly (p < or = 0.05) according to age (0-47 months). None of the children from Burkina-Faso or France had antibody levels > 1.0 microg/ml before one year of age. Thereafter, only 9.51% of French children in the 12- to 17-month age stratum and 19.2% over 4 years of age had antibody levels > 1.0 microg/ml. There were no non-detectable results for children over 4 years of age, and the means for natural detectable Hib CP antibodies were > 0.15 microg/ml for both populations. Hib invasive infections depend on climate, socioeconomic status and ethnic and genetic factors. In Burkina-Faso, the large number of infants and children under 4 years of age susceptible to Hib infections suggests that large scale vaccination programmes are needed soon after birth. However, it would first be necessary to evaluate such factors as the frequency of Hib diseases in this population
The meso-genomic era
A report from HGM2001, the sixth annual International Human Genome Meeting organized by The Human Genome Organisation (HUGO), Edinburgh, UK, 19-22 April 2001
Simulation of Laser Beam Propagation With a Paraxial Model in a Tilted Frame
We study the Schr\"odinger equation which comes from the paraxial
approximation of the Helmholtz equation in the case where the direction of
propagation is tilted with respect to the boundary of the domain. In a first
part, a mathematical analysis is made which leads to an analytical formula of
the solution in the simple case where the refraction index and the absorption
coefficients are constant. Afterwards, we propose a numerical method for
solving the initial problem which uses the previous analytical expression.
Numerical results are presented. We also sketch an extension to a time
dependant model which is relevant for laser plasma interaction
Simulation of Laser Propagation in a Plasma with a Frequency Wave Equation
The aim of this work is to perform numerical simulations of the propagation
of a laser in a plasma. At each time step, one has to solve a Helmholtz
equation in a domain which consists in some hundreds of millions of cells. To
solve this huge linear system, one uses a iterative Krylov method with a
preconditioning by a separable matrix. The corresponding linear system is
solved with a block cyclic reduction method. Some enlightments on the parallel
implementation are also given. Lastly, numerical results are presented
including some features concerning the scalability of the numerical method on a
parallel architecture
Fundamental parameters of Be stars located in the seismology fields of COROT
In preparation for the COROT space mission, we determined the fundamental
parameters (spectral type, temperature, gravity, vsini) of the Be stars
observable by COROT in its seismology fields (64 Be stars). We applied a
careful and detailed modeling of the stellar spectra, taking into account the
veiling caused by the envelope, as well as the gravitational darkening and
stellar flattening due to rapid rotation. Evolutionary tracks for fast rotators
were used to derive stellar masses and ages. The derived parameters will be
used to select Be stars as secondary targets (i.e. observed for 5 consecutive
months) and short-run targets of the COROT mission. Furthermore, we note that
the main part of our stellar sample is falling in the second half of the main
sequence life time, and that in most cases the luminosity class of Be stars is
inaccurate in characterizing their evolutionary status.Comment: 25 pages, 9 figures, Accepted for publication in A&
Mise en place dâoutils dâaide Ă la prescription des antibiotiques dans les Ă©tablissements de santĂ© (ES) des Pays de la Loire : crĂ©ation dâun thĂ©saurus rĂ©gional de protocoles dâantibiothĂ©rapie
Date du colloque : 2008</p
TERC polymorphisms are associated both with susceptibility to colorectal cancer and with longer telomeres.
Shorter telomeres have been associated with increased risk of malignancy, including colorectal cancer (CRC). Telomere length is heritable and may be an intermediate phenotype linked to genetic susceptibility to CRC
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