Aix-Marseille University

About: Aix-Marseille University is a education organization based out in Marseille, France. It is known for research contribution in the topics: Population & Galaxy. The organization has 24326 authors who have published 54240 publications receiving 1455416 citations. The organization is also known as: University Aix-Marseille & université d'Aix-Marseille.

Strong Constraints on the Rare Decays B-s(0) -> mu(+)mu(-) and B-0 -> mu(+)mu(-)

Abstract: A search for Bs0→μ+μ- and B0→μ+μ- decays is performed using 1.0 fb-1 of pp collision data collected at √s=7 TeV with the LHCb experiment at the Large Hadron Collider. For both decays, the number of observed events is consistent with expectation from background and standard model signal predictions. Upper limits on the branching fractions are determined to be B(Bs0→μ+μ-)<4.5(3.8)×10-9 and B(B0→μ+μ-)<1.0(0.81)×10-9 at 95% (90%) confidence level.

Using mobile phone data to predict the spatial spread of cholera.

Abstract: Effective response to infectious disease epidemics requires focused control measures in areas predicted to be at high risk of new outbreaks. We aimed to test whether mobile operator data could predict the early spatial evolution of the 2010 Haiti cholera epidemic. Daily case data were analysed for 78 study areas from October 16 to December 16, 2010. Movements of 2.9 million anonymous mobile phone SIM cards were used to create a national mobility network. Two gravity models of population mobility were implemented for comparison. Both were optimized based on the complete retrospective epidemic data, available only after the end of the epidemic spread. Risk of an area experiencing an outbreak within seven days showed strong dose-response relationship with the mobile phone-based infectious pressure estimates. The mobile phone-based model performed better (AUC 0.79) than the retrospectively optimized gravity models (AUC 0.66 and 0.74, respectively). Infectious pressure at outbreak onset was significantly correlated with reported cholera cases during the first ten days of the epidemic (p < 0.05). Mobile operator data is a highly promising data source for improving preparedness and response efforts during cholera outbreaks. Findings may be particularly important for containment efforts of emerging infectious diseases, including high-mortality influenza strains.

HerMES: SPIRE galaxy number counts at 250, 350, and 500 μm

Abstract: Emission at far-infrared wavelengths makes up a significant fraction of the total light detected from galaxies over the age of Universe. Herschel provides an opportunity for studying galaxies at the peak wavelength of their emission. Our aim is to provide a benchmark for models of galaxy population evolution and to test pre-existing models of galaxies. With the Herschel Multi-tiered Extra-galactic survey, HerMES, we have observed a number of fields of different areas and sensitivity using the SPIRE instrument on Herschel. We have determined the number counts of galaxies down to ~20 mJy. Our constraints from directly counting galaxies are consistent with, though more precise than, estimates from the BLAST fluctuation analysis. We have found a steep rise in the Euclidean normalised counts <100 mJy. We have directly resolved ~15% of the infrared extra-galactic background at the wavelength near where it peaks.