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Background: Streptococcus dysgalactiae subspecies equisimilis (SDSE) is an emerging global pathogen that can colonize and infect humans. Although most SDSE isolates possess the Lancefield group G carbohydrate, a significant minority have the group C carbohydrate. Isolates are further sub-typed on the basis of differences within the emm gene. To gain a better understanding of their molecular epidemiology and evolutionary relationships, multilocus sequence typing (MLST) analysis was performed on SDSE isolates collected from Australia, Europe and North America. Methodology/Principal Findings: The 178 SDSE isolates, representing 37 emm types, segregate into 80 distinct sequence types (STs) that form 17 clonal complexes (CCs). Eight STs recovered from all three continents account for >50% of the isolates. Thus, a small number of STs are highly prevalent and have a wide geographic distribution. Both ST and CC strongly correlate with group carbohydrate. In contrast, eleven STs were associated with >1 emm type, suggestive of recombinational replacements involving the emm gene; furthermore, 35% of the emm types are associated with genetically distant STs. Data also reveal a history of extensive inter- and intra-species recombination involving the housekeeping genes used for MLST. Sequence analysis of single locus variants identified through goeBURST indicates that genetic change mediated by recombination occurred ∼4.4 times more frequently than by point mutation. Conclusions/Significance: A few genetic lineages with an intercontinental distribution dominate among SDSE causing infections in humans. The distinction between group C and G isolates reflects recent evolution, and no long-term genetic isolation between them was found. Lateral gene transfer and recombination involving housekeeping genes and the emm gene are important mechanisms driving genetic variability in the SDSE population. [ABSTRACT FROM AUTHOR]

Difficult economic conditions must not be allowed to inhibit investment in air traffic management, otherwise serious capacity shortfalls could result in the medium to long term. This problem is compounded by the correlation between lack of capacity and environmental impact; EUROCONTROL has several initiatives designed to combat both. This paper describes the flight efficiency plan that EUROCONTROL is carrying out with the Civil Air Navigation Services Organisation (CANSO) and the International Air Transport Association (IATA), in addition to the Dynamic Management of the European Airspace Network (DMEAN) bridge to the Single European Sky ATM Research (SESAR) programme. It also discusses collaborative decision making, continuous descent approaches, collaborative environmental management and bespoke airside airport capacity enhancement activities. [ABSTRACT FROM AUTHOR]

This paper examines the time series properties of the monthly black-market dollar exchange rates of the Bulgarian lev, Czech koruna, East German mark, Hungarian forint, Polish zloty, Rumanian lei and Soviet ruble over the period 1955–1990. All series other than the mark exhibit a unit root in logarithms, and there is evidence of at least two cointegrating vectors linking the remaining rates. Weak exogeneity is rejected for the lev, forint and lei, but strong exogeneity cannot be rejected for the koruna, zloty and ruble, implying causality running from the latter group to the former group, which may be interpreted as reflecting channels of policy interdependence. [ABSTRACT FROM AUTHOR]

This paper examines the nature of stochastic volatility in the deutschemark/dollar and French franc/dollar exchange rates. In particular using a multivariate random walk stochastic volatility model the study examined whether volatility in each series can be ascribed to a single common trend. Results for univariate stochastic volatility models show very high persistence in the autoregressive component of volatility supporting the model specification where volatility follows a random walk. Estimation of the multivariate model reveals a very high correlation between the volatility innovations, and suggests that they follow a common trend, in essence the volatilities are cointegrated. A multivariate model with a single volatility trend is then estimated. Finally, support for this specification is further received when estimation of a stochastic volatility model for the ratio of the two series reveals no stochastic volatility present. [ABSTRACT FROM AUTHOR]

This paper examines the determinants of European bank risk-taking during major financial crisis. Using a sample of banks from 26 countries over the period 2005–2015, we examine the nature of the relationship between bank risk, bank characteristics, regulatory, institutional and macroeconomic variables. We use a dynamic panel data modeling structure to capture the potential discrepancies in risk-taking behavior. We subdivide our sample into two sub-samples (East Europe and West Europe countries). We show that macroeconomic and regulatory variables seem to have non-negligible impact on bank risk-taking attitudes. We document that the relationship between bank risk, internal and external factors differs across samples. [ABSTRACT FROM AUTHOR]

Streptococcus agalactiae (Group B Streptococcus, GBS) is a commensal of the digestive and genitourinary tracts of humans that emerged as the leading cause of bacterial neonatal infections in Europe and North America during the 1960s. Due to the lack of epidemiological and genomic data, the reasons for this emergence are unknown. Here we show by comparative genome analysis and phylogenetic reconstruction of 229 isolates that the rise of human GBS infections corresponds to the selection and worldwide dissemination of only a few clones. The parallel expansion of the clones is preceded by the insertion of integrative and conjugative elements conferring tetracycline resistance (TcR). Thus, we propose that the use of tetracycline from 1948 onwards led in humans to the complete replacement of a diverse GBS population by only few TcR clones particularly well adapted to their host, causing the observed emergence of GBS diseases in neonates.