On the Atomic Photoeffect in Non-relativistic QED

In this paper we present a mathematical analysis of the photoelectric effect for one-electron atoms in the framework of non-relativistic QED. We treat photo-ionization as a scattering process where in the remote past an atom in its ground state is targeted by one or several photons, while in the distant future the atom is ionized and the electron escapes to spacial infinity. Our main result shows that the ionization probability, to leading order in the fine-structure constant, $\alpha$, is correctly given by formal time-dependent perturbation theory, and, moreover, that the dipole approximation produces an error of only sub-leading order in $\alpha$. In this sense, the dipole approximation is rigorously justified.Comment: 25 page

Influence of socioeconomic factors on pregnancy outcome in women with structural heart disease

OBJECTIVE: Cardiac disease is the leading cause of indirect maternal mortality. The aim of this study was to analyse to what extent socioeconomic factors influence the outcome of pregnancy in women with heart disease.  METHODS: The Registry of Pregnancy and Cardiac disease is a global prospective registry. For this analysis, countries that enrolled ≥10 patients were included. A combined cardiac endpoint included maternal cardiac death, arrhythmia requiring treatment, heart failure, thromboembolic event, aortic dissection, endocarditis, acute coronary syndrome, hospitalisation for cardiac reason or intervention. Associations between patient characteristics, country characteristics (income inequality expressed as Gini coefficient, health expenditure, schooling, gross domestic product, birth rate and hospital beds) and cardiac endpoints were checked in a three-level model (patient-centre-country).  RESULTS: A total of 30 countries enrolled 2924 patients from 89 centres. At least one endpoint occurred in 645 women (22.1%). Maternal age, New York Heart Association classification and modified WHO risk classification were associated with the combined endpoint and explained 37% of variance in outcome. Gini coefficient and country-specific birth rate explained an additional 4%. There were large differences between the individual countries, but the need for multilevel modelling to account for these differences disappeared after adjustment for patient characteristics, Gini and country-specific birth rate.  CONCLUSION: While there are definite interregional differences in pregnancy outcome in women with cardiac disease, these differences seem to be mainly driven by individual patient characteristics. Adjustment for country characteristics refined the results to a limited extent, but maternal condition seems to be the main determinant of outcome

Etienne de Gröer urbaniste à la ville de Coimbra

Etude historique et critique de l'activité au Portugal d'Etienne de Grôer, architecte et urbaniste, professeur de l'Institut d'Urbanisme de l'Université de Paris (1930-40). L'urbanisme au Portugal. Le XXe siècle. Les urbanistes étrangers au Portugal: l'importance de l'école française. Etienne de Grôer avant son arrivée au Portugal (sa vie et sa formation, les travaux en France, la pensée et les écrits, la cité jardin. L'activité d'Etienne de Grôer au Portugal Etienne de Grôer urbaniste de Coimbra. Conclusions. Région de Coimbra, une région jardin.PARIS1-BU Pierre Mendès-France (751132102) / SudocSudocFranceF

Chapter 9. Universal DVB-3GPP broadcast layer, an enabler for new business in mobile broadcasting landscape

This chapter aims at promoting the tremendous asset a cooperation of broadband and broadcast deliveries could provide to cope with the data tsunami announced for the mobile access networks. A clever blend of state-of-the-art 3GPP and DVB standards has been designed to provide a broadcast overlay optimized for mobile and operated in conjunction with a broadband unicast access. This chapter highlights the win-win situation for each actor of the multimedia value chain, which should result from such broadband/broadcast cooperation

The effect of oxygen on ball-milling of a near-equiatomic FeV sigma phase

International audienceA coarse-grained near-equiatomic tetragonal sigma phase Fe48V52 is milled in argon in a vibratory mill with a small steady air supply. The oxygen content increases regularly at a rate of about 0.25 at. %/h. Besides a classical short step, during which the sigma phase transforms into an alpha phase, two main steps occur. During the first step, from ∼40 to ∼140 h of milling, the bcc alpha phase is enriched in iron and heterogeneous because of a preferential oxidation of vanadium atoms. The bcc phase is partially amorphized as it is when milling in the absence of oxygen and nanocrystalline vanadium oxides do form. The second step is characterized by the coarsening of vanadium oxide particles and by the formation of ternary ferrous oxides. The results are discussed in the light of a vacancy mechanism proposed recently to account for the high stability of oxide nanoclusters in oxide dispersion strengthened Fe-based alloys processed by ball milling

Superferromagnetism in mechanically alloyed fcc Fe23Cu77 with bimodal cluster size distribution

International audienceMagnetic measurements, x-ray diffraction and Mössbauer spectroscopy were used to characterize a nanostructured fcc Fe23Cu77 at.% alloy prepared by high-energy ball-milling, addressing in particular the effect of clustering on the nature of the interacting magnetic entities. The interpretation of magnetization measurements leads to the conclusion that grains, whose mean size is ~16 nm, contain two populations of magnetic Fe-rich nanoclusters with a bimodal size distribution. These two sets of clusters contain about 14 and 400 Fe atoms and have magnetic moments of 30 µB and 860 µB, respectively. The inter-cluster ferromagnetic interactions that lead to superferromagnetism with a Curie temperature TC~220 K can be described by a mean field determined by the smaller clusters only, which account for 90% of the magnetization