We report on a two-arm hybrid high-power laser system (HPLS) able to deliver 2 × 10 PW femtosecond pulses, developed at the Bucharest-Magurele Extreme Light Infrastructure Nuclear Physics (ELI-NP) Facility. A hybrid front-end (FE) based on a Ti:sapphire chirped pulse amplifier and a picosecond optical parametric chirped pulse amplifier based on beta barium borate (BBO) crystals, with a cross-polarized wave (XPW) filter in between, has been developed. It delivers 10 mJ laser pulses, at 10 Hz repetition rate, with more than 70 nm spectral bandwidth and high-intensity contrast, in the range of 1013:1. The high-energy Ti:sapphire amplifier stages of both arms were seeded from this common FE. The final high-energy amplifier, equipped with a 200 mm diameter Ti:sapphire crystal, has been pumped by six 100 J nanosecond frequency doubled Nd:glass lasers, at 1 pulse/min repetition rate. More than 300 J output pulse energy has been obtained by pumping with only 80% of the whole 600 J available pump energy. The compressor has a transmission efficiency of 74% and an output pulse duration of 22.7 fs was measured, thus demonstrating that the dual-arm HPLS has the capacity to generate 10 PW peak power femtosecond pulses. The reported results represent the cornerstone of the ELI-NP 2 × 10 PW femtosecond laser facility, devoted to fundamental and applied nuclear physics research.

We summarize the findings from an interlaboratory study conducted between ten international research groups and investigate the use of the commonly used maximum separation distance and local concentration thresholding methods for solute clustering quantification. The study objectives are: to bring clarity to the range of applicability of the methods; identify existing and/or needed modifications; and interpretation of past published data. Participants collected experimental data from a proton-irradiated 304 stainless steel and analyzed Cu-rich and Ni–Si rich clusters. The datasets were also analyzed by one researcher to clarify variability originating from different operators. The Cu distribution fulfills the ideal requirements of the maximum separation method (MSM), namely a dilute matrix Cu concentration and concentrated Cu clusters. This enabled a relatively tight distribution of the cluster number density among the participants. By contrast, the group analysis of the Ni–Si rich clusters by the MSM was complicated by a high Ni matrix concentration and by the presence of Si-decorated dislocations, leading to larger variability among researchers. While local concentration filtering could, in principle, tighten the results, the cluster identification step inevitably maintained a high scatter. Recommendations regarding reporting, selection of analysis method, and expected variability when interpreting published data are discussed.

In the “Weather on Other Worlds” Spitzer Exploration Science program, we surveyed 44 nearby L3–T8 dwarfs for spot-induced rotational variability. Among single L3–L9.5 dwarfs, we found that 80% are variable at >0.2% in the 3–5 μm wavelength range, while 36% of T0–T8 were variable at >0.4%. Taking into account viewing angle and sensitivity considerations, both of these findings are consistent with spots being present on ~100% of L3–T8 dwarfs. Intriguingly, we find a tentative association (92% confidence) between low surface gravity and high-amplitude variability among L3–L5.5 dwarfs. Although we can not confirm whether lower gravity is also correlated with a higher incidence of variables, the result is promising for the characterization of directly imaged young extrasolar planets through variability.

We study self-duality of Grothendieck's blended extensions in the context of a tannakian category. The set of equivalence classes of symmetric, resp. antisymmetric, blended extensions is naturally endowed with a torsor structure, which enables us to compute the unipotent radical of the associated monodromy groups in various situations.

We evaluated the usefulness of adding weekly methicillin-resistant Staphylococcus aureus (MRSA) screening to our established admission screening and clinical sampling in 4 acute care units of a university hospital. Our results suggest that weekly MRSA screening allows the detection of 56.1% of all cases of hospital-acquired MRSA carriage. These cases would have remained undetected had admission screening and clinical sampling been the only types of surveillance in place.

The scientific community will remember Peter Läuger as an exceptional man combining a generous personality and a sharp and skilful mind. He was able to attract by his views the interest of a large spectrum of biologists concerned by the mechanism of ion translocation through membranes. Yet, he was not a man with a single technique or theory. Using an authentically multidisciplinary approach, his ambition was to ‘understand transmembrane transport at the microscopic level, to capture its dynamics in the course of defined physiological processes’ (1987). According to him, ‘new concepts in the molecular physics of proteins’ had to be imagined, and ‘the traditional static picture of proteins has been replaced by the notions that proteins represent dynamic structures, subjected to conformational fluctuations covering a very wide time-range’ (1987).

Fourteen variables including socioeconomic factors, demographic variables, reproductive ideals and contact with family planning programmes are tested as correlates of contraceptive use among a low-income population of Cali, Colombia. Data from surveys in 1976 and 1978 show two factors to be key determinants: number of children and contact with the local contraceptive distribution post. The availability of family planning services is discussed as an important concern for policy makers.

This study examines effects and interactions of socioeconomic status, access to water supply and sanitation, and breast-feeding practices in relation to child growth in two provincial cities in the Philippines. Multivariate analysis identified food expenditure per head, education of the household head and gender of the child as significant predictors of nutritional status. The duration of partial and full breast-feeding was negatively (though non-significantly) associated with growth. Sanitation facilities and breast-feeding are, however, important determinants during the first year of life. Among children over 1 year of age, socioeconomic variables and gender are the most important predictors. Breast-feeding is shown to provide more important health benefits for children in lower income households. The need for further studies on the causes of gender differences in nutritional status was apparent.

LC-NANOP is an ESF EUROCORES SONS Collaborative Research Project that is addressing an innovative approach to self-organized nanostructures by combination of a variety of organic, inorganic and metal scaffolds with the unique self-organization properties of liquid crystals to obtain liquid crystal nano-particles. LC-NANOP is concerned with the synthesis, analysis, characterization, modeling and physico-chemical properties of super- and supra-molecular systems which are formed from a nano-particle as a central scaffold, surrounded by a layer of liquid crystal. The self-organization properties of the liquid crystal coating is the driving force leading to the self-assembly of the nano-particles into secondary or tertiary hierarchical structures, with emphasis on the systematic variation of nano-particle size, chirality, shape and functionality. This bottom-up approach to nano-structuring is very powerful as it combines the extraordinary variety of morphologies that liquid crystals present with the combination of functional entities, relevant for chemical, biological, optoelectronic, and photonic tasks, etc, to create ordered nano-structures that can be controlled by external stimuli.

There is currently a great interest in the preparation of nanostructured magnetic films possessing well-defined structures and controlled properties. Recent progresses in colloidal nanocrystals synthesis and processing have led to new methods for producing films and superstructures made with these materials. Hybrid films have been prepared by organizing functionalized magnetite nanoparticles in large patterns using the Langmuir Blodgett technique. Magnetite nanoparticles with an average particle diameter of 39nm have been prepared and then coated with amphiphilic molecules. The resulting decorated particles, with a hydrophobic outer layer, have proven suitable for being processed by the LB technique. The microstructure and the compacity of the nanoparticle arrays appear to depend on the nature of the organic moiety used to decorate the nanoparticles (carboxylate or phosphonate end-capped stilbene derivatives).

We evaluated the validity of the formula of Rhame and Sudderth to estimate the cumulative incidence of nosocomial bacteremia from prevalence studies. The observed cumulative incidence was threefold higher than the calculated cumulative incidence. We do not recommend converting prevalence into incidence data for nosocomial bloodstream infections.