1,313 research outputs found
Handle with Care: Umbrella Clauses and MFN Treatment in Investment Arbitration
A large number of BITs concluded by France contain quite a peculiar clause (for instance Article 10 BIT with Argentina), which has been recently the object of questionable interpretations and applications in EDF International S.A. et al. v. Argentina and Mr. Franck Charles Arif v. Moldova. Both tribunals allowed the claimants to benefit, through the MNF clause, from umbrella clauses contained in BITs with third States. It is argued that neither tribunal has rigorously interpreted the relevant provisions in the basic treaty, nor ensured compliance with the ejusdem generis principle. The legal uncertainty that surrounds these provisions is detrimental for foreign investors and States alike. Concerned States should consider taking the measures necessary to clarify, jointly or individually, the content of these provisions and of the obligations stemming from them
Robustness of ergodic properties of non-autonomous piecewise expanding maps
Recently, there has been an increasing interest in non-autonomous composition of perturbed hyperbolic systems: composing perturbations of a given hyperbolic map results in statistical behaviour close to that of . We show this fact in the case of piecewise regular expanding maps. In particular, we impose conditions on perturbations of this class of maps that include situations slightly more general than what has been considered so far, and prove that these are stochastically stable in the usual sense. We then prove that the evolution of a given distribution of mass under composition of time-dependent perturbations (arbitrarily—rather than randomly—chosen at each step) close to a given map remains close to the invariant mass distribution of . Moreover, for almost every point, Birkhoff averages along trajectories do not fluctuate wildly. This result complements recent results on memory loss for non-autonomous dynamical systems
Revealing dynamics, communities and criticality from data
Complex systems such as ecological communities and neuron networks are essential parts of our everyday lives. These systems are composed of units which interact through intricate networks. The ability to predict sudden changes in the dynamics of these networks, known as critical transitions, from data is important to avert disastrous consequences of major disruptions. Predicting such changes is a major challenge as it requires forecasting the behaviour for parameter ranges for which no data on the system is available. We address this issue for networks with weak individual interactions and chaotic local dynamics. We do this by building a model network, termed an {}, consisting of the underlying local dynamics and a statistical description of their interactions. We show that behaviour of such networks can be decomposed in terms of an emergent deterministic component and a {} term. Traditionally, such fluctuations are filtered out. However, as we show, they are key to accessing the interaction structure. { We illustrate this approach on synthetic time-series of realistic neuronal interaction networks of the cat cerebral cortex and on experimental multivariate data of optoelectronic oscillators. } We reconstruct the community structure by analysing the stochastic fluctuations generated by the network and predict critical transitions for coupling parameters outside the observed range
Explaining Africa’s public consumption procyclicality : revisiting old evidence
This paper compiles a novel dataset of time-varying measures of government consumption cyclicality for a panel of 46 African economies between 1960 and 2014. Government consumption has, generally, been highly procyclical over time in this group of countries. However, sample averages hide serious heterogeneity across countries with the majority of them showing procyclical behavior despite some positive signs of graduation from the “procyclicality trap” in a few cases. By means of weighted least squares regressions, we find that more developed African economies tend to have a smaller degree of government consumption procyclicality. Countries with higher social fragmentation and those are more reliant on foreign aid inflows tend to have a more procyclical government consumption policy. Better governance promotes counter- cyclical fiscal policy whileincreased democracy dampens it. Finally, some fiscal rules are important in curbing the procyclical behavior of government consumption.info:eu-repo/semantics/publishedVersio
Quantum diffusion with disorder, noise and interaction
Disorder, noise and interaction play a crucial role in the transport
properties of real systems, but they are typically hard to control and study
both theoretically and experimentally, especially in the quantum case. Here we
explore a paradigmatic problem, the diffusion of a wavepacket, by employing
ultra-cold atoms in a disordered lattice with controlled noise and tunable
interaction. The presence of disorder leads to Anderson localization, while
both interaction and noise tend to suppress localization and restore transport,
although with completely different mechanisms. When only noise or interaction
are present we observe a diffusion dynamics that can be explained by existing
microscopic models. When noise and interaction are combined, we observe instead
a complex anomalous diffusion. By combining experimental measurements with
numerical simulations, we show that such anomalous behavior can be modeled with
a generalized diffusion equation, in which the noise- and interaction-induced
diffusions enter in an additive manner. Our study reveals also a more complex
interplay between the two diffusion mechanisms in regimes of strong interaction
or narrowband noise.Comment: 11 pages, 10 figure
Correlation function of weakly interacting bosons in a disordered lattice
One of the most important issues in disordered systems is the interplay of
the disorder and repulsive interactions. Several recent experimental advances
on this topic have been made with ultracold atoms, in particular the
observation of Anderson localization, and the realization of the disordered
Bose-Hubbard model. There are however still questions as to how to
differentiate the complex insulating phases resulting from this interplay, and
how to measure the size of the superfluid fragments that these phases entail.
It has been suggested that the correlation function of such a system can give
new insights, but so far little experimental investigation has been performed.
Here, we show the first experimental analysis of the correlation function for a
weakly interacting, bosonic system in a quasiperiodic lattice. We observe an
increase in the correlation length as well as a change in shape of the
correlation function in the delocalization crossover from Anderson glass to
coherent, extended state. In between, the experiment indicates the formation of
progressively larger coherent fragments, consistent with a fragmented BEC, or
Bose glass.Comment: 16 pages, 8 figure
Lifestyles and discomfort in a sample of young Romanian students
Introduction. The 40.3% of the Romanian youth population is at risk of poverty or social exclusion, and, in addition, the abuse of substances increases. It was interesting to evaluate the attitudes shared by pupils as well as their knowledge of these substances with a view to analyzing causes and types of risky behaviour in young people. Methods. This is an observational study on the harassment influence in the lifestyle of a sample of Craiova high-school students The Fagerstr\uf6m Test was applied to evaluate the degree of nicotine dependence, and the data processed to assess the Odds Ratio. Results. The sample was composed by 1,980 students with an average age of 17, of which 1,727 correctly responded to the questionnaire. The 37.4% of students admit to smoke, and the 67% to drink alcohol. The Fagerstr\uf6m test showed that the 68.2% of respondents are not highly addicted to smoke while the 31.8% was associated with a middle-to-high addiction level. A worrying weekly consumption of beer has been registered in the students. Regarding psychological distress caused by harassment a high Odds Ratio was recorded between the smokers and the drug users. Conclusions. More than half of students did not know about the health consequences of smoking, and the same result was recorded about the consumption of alcohol. A special attention should be done to the understanding of harassment problem in the young people. In fact, almost all the respondents declared to have suffered abuse and admits to use drug and cigarettes
Neurosci Lett
Recently, the P86L alteration in CALHM1 (calcium homeostasis modulator-1) was reported to be associated with Alzheimer's disease (AD). Moreover, the risk allele increased amyloid-beta (A beta) levels in conditioned media from cultured cells. Therefore, we hypothesized that CALHM1 P86L may modulate A beta or tau levels in cerebrospinal fluid (CSF). Nearly 200 individuals with AD or other cognitive disorders were included for CSF analysis and CALHM1 genotyping. No significant differences in CSF levels of A beta 42, tau or phospho-tau were found across the various CALHM1 genotypes. In conclusion, we found no evidence that CALHM1 P86L is associated with altered CSF levels of the investigated AD biomarkers
Women and Illegal Activities: Gender Differences and Women's Willingness to Comply Over Time
In recent years the topics of illegal activities such as corruption or tax evasion have attracted a great deal of attention. However, there is still a lack of substantial empirical evidence about the determinants of compliance. The aim of this paper is to investigate empirically whether women are more willing to be compliant than men and whether we observe (among women and in general) differences in attitudes among similar age groups in different time periods (cohort effect) or changing attitudes of the same cohorts over time (age effect) using data from eight Western European countries from the World Values Survey and the European Values Survey that span the period from 1981 to 1999. The results reveal higher willingness to comply among women and an age rather than a cohort effect. Working Paper 06-5
The Size and Growth of the Hidden Economy in Norway
The present size of the hidden economy in Norway is between 4 and 6 percent of GDP, of which
hidden labor income constitutes about half. A survey approach reveals that 415 of the population is
of the opinion that people in general accept income from moonlighting that is not reported, and 213
believes that this share of acceptance is on the increase. Furthermore, surveys clearly show that
hidden labor services are of satisfactory quality, that they mainly are paid for in cash, but with
checks being increasingly used, and that buyers find it easier to obtain services from the hidden labor
market than from the regular one. A shortening of the work week in order to alleviate unemployment
may result in an increased supply of hidden labor
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