Convergence and shocks in the road to EU: Empirical investigations for Bulgaria and Romania

Despite their progress Bulgaria and Romania significantly differ from the EU economies. In this article, on the basis of the theoretical and empirical achievements of the theory of optimal and (endogenous) currency areas we study to what extent the two South European economies are able to adopt the common economic (and above all monetary) policy of the EU, and to what extent the convergence to the EU stimulates the economic development of these countries. Despite the similarities, the two countries now differ fundamentally in their choice of a monetary regime – while Romania uses inflation targeting and a flexible exchange rate, Bulgaria has adopted a currency board regime. For this purpose we analyze: (i) the degree of nominal, real and financial convergence and synchronization of the economic cycle with that of the European Union (using unconditional β convergence approach). Income and price levels, inflation rate, interest rate, monetary aggregates, credit, productivity etc. are among the studied variables; (ii) the resistance to different external and internal shocks (using VAR model) as well as (iii) the mechanisms for balancing and absorption of these shocks. To give a better comparative picture we compose the panel including Hungary and Czech Republic.http://deepblue.lib.umich.edu/bitstream/2027.42/40196/3/wp810.pd

Convergence and shocks in the road to EU: Empirical investigations for Bulgaria and Romania

Despite their progress Bulgaria and Romania significantly differ from the EU economies. In this article, on the basis of the theoretical and empirical achievements of the theory of optimal and (endogenous) currency areas we study to what extent the two South European economies are able to adopt the common economic (and above all monetary) policy of the EU, and to what extent the convergence to the EU stimulates the economic development of these countries. Despite the similarities, the two countries now differ fundamentally in their choice of a monetary regime – while Romania uses inflation targeting and a flexible exchange rate, Bulgaria has adopted a currency board regime. For this purpose we analyze: (i) the degree of nominal, real and financial convergence and synchronization of the economic cycle with that of the European Union (using unconditional ß convergence approach). Income and price levels, inflation rate, interest rate, monetary aggregates, credit, productivity etc. are among the studied variables; (ii) the resistance to different external and internal shocks (using VAR model) as well as (iii) the mechanisms for balancing and absorption of these shocks. To give a better comparative picture we compose the panel including Hungary and Czech Republic.convergence, shocks, EU enlargement, Bulgaria and Romania

Les cours d'eau récepteurs de rejets de stations d'épuration : le cas de la Mauldre (Île-de-France), un milieu sous très haute pression

L'étude des impacts des rejets des stations d'épuration communales sur les cours d'eau récepteurs est généralement conduite selon des méthodes d'analyses ponctuelles en rivière. Mais ces méthodes ne donnent pas des résultats satisfaisants car elles ne tiennent pas compte à la fois de la qualité des cours d'eau et des rejets, et nient le continuum de la rivière en analysant des points successifs. D'autres méthodes, globales, tiennent compte des flux en rivière et en station et fournissent des résultats plus représentatifs des phénomènes qui se produisent en rivière. Une étude de cas a été menée sur la Mauldre et ses affluents. Deux méthodes de calcul d'impact ponctuel ont été utilisées, le ratio de dilution et le taux de pollution. Un bilan des flux en rivière et en station a été mis au point pour l'analyse globale. Celle-ci a été complétée par un bilan global des impacts, issu d'une approche systémique qui élargit le périmètre des investigations. Cette dernière méthode demande l'acquisition de peu de données en comparaison des autres. Elle est également plus intégratrice, replace le problème posé dans un contexte plus vaste et permet ainsi d'y apporter une réponse intéressante.A case study was undertaken on the river Mauldre and its tributaries. The Mauldre is a small river in the Seine catchment, the ecological and biochemical functioning of which is highly damaged by human activities. This type of impact study is generally carried out according to methods involving specific point analyses. We used two of these calculation methods: the ratio of dilution and the rate of pollution. However, their applications do not give satisfactory results because they do not take into account the quality of the rivers and of the wastewater treatment plant effluents. Furthermore, they ignore the river continuum concept by analysing successive episodes. Both calculation methods provide similar results: impacts are decreasing downstream. On the contrary, river pollution measurements show an increasing impact downstream. Therefore we used global methods that take into account more of the river phenomena. First we developed a more satisfactory assessment of pollutant loads from the river and wastewater treatment plants. This method consists of a one-dimensional basic model and gives a global description of the river behaviour. This analysis was enhanced by a global assessment of the impacts, resulting from a systems analysis approach (cf. Joël de Rosnay's work, " Le macroscope "). This approach consists of identifying structural and functional aspects of the studied system, using a new vocabulary: we talk of elements, frontiers and internal or external links. The usual framework is broadened - the central question of the paper is posed in a larger context, considering the whole catchment and its components, and affords brief answers. This method provides many points of view on our studied subject, and highlights new components and new relations among them. At the end of the study we found a very interesting relation between inhabitants of the catchment and low flow, which found expression in the population stress index. The last method we used needs fewer data than the others do but still give us accurate and high significant indices of the impact of wastewater treatment plant effluents

Biased gene conversion and GC-content evolution in the coding sequences of reptiles and vertebrates.

Mammalian and avian genomes are characterized by a substantial spatial heterogeneity of GC-content, which is often interpreted as reflecting the effect of local GC-biased gene conversion (gBGC), a meiotic repair bias that favors G and C over A and T alleles in high-recombining genomic regions. Surprisingly, the first fully sequenced nonavian sauropsid (i.e., reptile), the green anole Anolis carolinensis, revealed a highly homogeneous genomic GC-content landscape, suggesting the possibility that gBGC might not be at work in this lineage. Here, we analyze GC-content evolution at third-codon positions (GC3) in 44 vertebrates species, including eight newly sequenced transcriptomes, with a specific focus on nonavian sauropsids. We report that reptiles, including the green anole, have a genome-wide distribution of GC3 similar to that of mammals and birds, and we infer a strong GC3-heterogeneity to be already present in the tetrapod ancestor. We further show that the dynamic of coding sequence GC-content is largely governed by karyotypic features in vertebrates, notably in the green anole, in agreement with the gBGC hypothesis. The discrepancy between third-codon positions and noncoding DNA regarding GC-content dynamics in the green anole could not be explained by the activity of transposable elements or selection on codon usage. This analysis highlights the unique value of third-codon positions as an insertion/deletion-free marker of nucleotide substitution biases that ultimately affect the evolution of proteins

Biased gene conversion and GC-content evolution in the coding sequences of reptiles and vertebrates.

Mammalian and avian genomes are characterized by a substantial spatial heterogeneity of GC-content, which is often interpreted as reflecting the effect of local GC-biased gene conversion (gBGC), a meiotic repair bias that favors G and C over A and T alleles in high-recombining genomic regions. Surprisingly, the first fully sequenced nonavian sauropsid (i.e., reptile), the green anole Anolis carolinensis, revealed a highly homogeneous genomic GC-content landscape, suggesting the possibility that gBGC might not be at work in this lineage. Here, we analyze GC-content evolution at third-codon positions (GC3) in 44 vertebrates species, including eight newly sequenced transcriptomes, with a specific focus on nonavian sauropsids. We report that reptiles, including the green anole, have a genome-wide distribution of GC3 similar to that of mammals and birds, and we infer a strong GC3-heterogeneity to be already present in the tetrapod ancestor. We further show that the dynamic of coding sequence GC-content is largely governed by karyotypic features in vertebrates, notably in the green anole, in agreement with the gBGC hypothesis. The discrepancy between third-codon positions and noncoding DNA regarding GC-content dynamics in the green anole could not be explained by the activity of transposable elements or selection on codon usage. This analysis highlights the unique value of third-codon positions as an insertion/deletion-free marker of nucleotide substitution biases that ultimately affect the evolution of proteins

rac-(4aR,8aR)-2,3-Diphenyl-4a,5,6,7,8,8a-hexa­hydro­quinoxaline

The structure of the title racemic compound, C20H20N2, shows close similarity to that of the enanti­omerically pure (4aR,8aR)-2,3-diphenyl-4a,5,6,7,8,8a-hexa­hydro­quinoxaline [Wang & Ye (2008 ▶). Acta Cryst. E64, o359–o359]. The similarity applies to the unit-cell parameters as well as to the packing of the constituent mol­ecules. Similar packing is conditioned by a lack of directed inter­molecular inter­actions such as hydrogen bonds in either structure

Combined multilateration with machine learning for enhanced aircraft localization

In this paper, we present an aircraft localization solution developed in the context of the Aircraft Localization Competition and applied to the OpenSky Network real-world ADS-B data. The developed solution is based on a combination of machine learning and multilateration using data provided by time synchronized ground receivers. A gradient boosting regression technique is used to obtain an estimate of the geometric altitude of the aircraft, as well as a first guess of the 2D aircraft position. Then, a triplet-wise and an all-in-view multilateration technique are implemented to obtain an accurate estimate of the aircraft latitude and longitude. A sensitivity analysis of the accuracy as a function of the number of receivers is conducted and used to optimize the proposed solution. The obtained predictions have an accuracy below 25 m for the 2D root mean squared error and below 35 m for the geometric altitude

Data-driven airborne collision risk modelling using a probability density function

This paper introduces a novel data-driven mid-air collision risk model for an aircraft flying through a flow of aircraft, modelled using a probability density function to describe position, and a speed vector. The proposed model is, compared to traditional Monte-Carlo simulations, computationally efficient and, thus, facilitates exploration of risks as a function of key parameters, such as aircraft performance, or with different scenarios. Compared with traditional collision risk models, the proposed solution can handle more complex trajectories and traffic flows. The usefulness of the novel model is illustrated on a real-world example by applying it to the terminal airspace of Zurich airport, Switzerland. Specifically, the probability of collisions between go-arounds on Runway 14 and departures on Runway 16 is quantified. The results of the model were validated through comparison with Monte-Carlo simulations, with comparable outcomes but significantly lower computational costs

GNSS jamming and its effect on air traffic in Eastern Europe

Global navigation satellite systems technology is at the core of modern air traffic navigation. Aircraft use it to estimate their position, while air navigation service providers rely on services such as automatic dependent surveillance broadcast which have been enabled by this technology. Since satellite signals are very low in power, they are susceptible to radio frequency interference activities, which can have a significant impact on aviation. This paper illustrates how crowd-sourced automatic dependent surveillance data transmitted by aircraft can be used to gain situational awareness about radio frequency interference and how air traffic over Eastern Europe has been impacted by interference activities over a period spanning from February to August 2022. The results suggest that satellite navigation signals were subject to interference of varying strength and duration. We observed several days when more than 1000 flights were affected, representing 60% of the daily traffic in the analysed area. Furthermore, the extent of the interference impact on aviation depends on the altitude of the aircraft, as low-flying aircraft tend to be less affected by interference than the ones flying at higher altitudes. Consequently, this paper contributes to a better understanding of how civil aviation is affected by radio frequency interference and where such disturbances may occur