Measuring international skilled migration: new estimates controlling for age of entry

Recent data on international skilled migration define skilled migrants according to education level independently of whether education has been acquired in the home or in the host country. In this paper we use immigrants’ age of entry as a proxy for where education has been acquired. Data on age of entry are available from a subset of receiving countries which together represent more than 3/4 of total skilled immigration to the OECD. Using these data and a simple gravity model, we estimate the age-of-entry structure of skilled immigration and propose alternative brain drain measures by excluding those arrived before age 12, 18 and 22. The results for 2000 show that on average, 68% of the global brain drain is accounted for by emigration of people aged 22 or more upon arrival (78% and 87% for the 18 and 12 year old thresholds, respectively). For some countries this indeed makes a substantial difference. However, cross-country differences are globally maintained, resulting in extremely high correlation levels between corrected and uncorrected rates. Similar results are obtained for 1990

Remittances and inequality: a dynamic migration model

We develop a model to study the effects of migration and remittances on inequality in the origin communities. While wealth inequality is shown to be monotonically reduced along the time-span, the short- and the long-run impacts on income inequality may be of opposite signs, suggesting that the dynamic relationship between migration/remittances and inequality may well be characterized by an inverse U-shaped pattern. This is consistent with the findings of the empirical literature, yet offers a different interpretation from the usually assumed migration network effects. With no need to endogenize migration costs through the role of migration networks, we generate the same result via intergenerational wealth accumulation

Multidrug-resistant Pseudomonas aeruginosa producing PER-1 extended-spectrum serine-beta-lactamase and VIM-2 metallo-beta-lactamase.

[No abstract available]Europena Training and Mobility of Researchers Network on Metallo-beta-Lactamases (grant no. FMRX-CT98-0232

Biochemical characterization of the POM-1 metallo-β-lactamase from Pseudomonas otitidis

The POM-1 metallo--lactamase is a subclass B3 resident enzyme produced by Pseudomonas otitidis, a pathogen causing otic infections. The enzyme was overproduced in Escherichia coli BL21(DE3), purified by chromatography, and subjected to structural and functional analysis. The purified POM-1 is a tetrameric enzyme of broad substrate specificity with higher catalytic activities with penicillins and carbapenems than with cephalosporins

Abstract basins of attraction

Abstract basins appear naturally in different areas of several complex variables. In this survey we want to describe three different topics in which they play an important role, leading to interesting open problems

Melting and refreezing beneath Roi Baudouin Ice Shelf (East Antarctica) inferred from radar, GPS, and ice core data

Ice-penetrating radar profiles across the grounding line of a small ice-rise promontory located within the Roi Baudouin Ice Shelf in the Dronning Maud Land sector of East Antarctica show downward dipping englacial radar-detected reflectors. Model results indicate that this reflector pattern is best fit by including basal melting of at least 15 cm a-1. This rate of melting is low compared with rates observed on larger ice shelves in both West and East Antarctica. Ice cores extracted from a rift system close to the ice-rise promontory show several meters of marine ice accreted beneath the shelf. These observations of low rates of basal melting, and limited distribution of accreted marine ice suggest that either Antarctic surface water may reach the ice shelf base or that circulation beneath the shelf is likely dominated by the production of high salinity shelf water rather than the incursion of circumpolar deep water, implying a weak sub-shelf circulation system here. Many of the ice shelves located along the coast of Dronning Maud Land are, like Roi Baudouin Ice Shelf, characterized by frequent ice rises and promontories. Therefore, it is highly likely that these are also of shallow bathymetry and are subject to similarly weak side-shelf basal melting and refreezing