Trends in ozone concentrations in the Iberian Peninsula by quantile regression and clustering

In this paper, 10-years of ozone (O3) hourly concentrations collected over the period 2000–2009 in the Iberian Peninsula (IP) are analyzed using records from 11 background sites. All the selected monitoring stations present an acquisition efficiency above 85%. The changes in surface ozone over the Iberian Peninsula are examined by means of quantile regression, which allows to analyse the trends not only in the mean but in the overall data distribution. In addition, the ozone hourly concentrations records are clustered on the basis of their resulting distributions. The analysis showed that high altitude stations (>900 m) have higher background O3 concentrations (∼80 μg m−3). The same magnitude of background O3 concentrations is found in stations near the Mediterranean Sea. On the other hand, the rural stations near the Atlantic coast present lower background values (∼50–60 μg m−3) than those of Mediterranean influence. The two sub-urban stations exhibit the lowest background concentrations (∼45 μg m−3). The results of the quantile regression show a very distinct behaviour of the data distribution, the slopes for a fixed quantile are not the same over IP, reflecting the spatial dependence of O3 trends. Hence the rate of temporal change is not the same for all parts of the data distribution, as implicitly assumed in ordinary regression. The lower quantile (percentile 5) presents higher rates of change than the middle (percentile 50) and the upper quantile (percentile 95). The clustering procedure reveals what has been already detected in the quantile regression. The station with highest rates of decrease on the O3 concentrations (easternmost station of IP) is isolated and then other clusters are formed among the moderately positive/negative O3 trends around the IP. The clustering procedure highlighted that the largest trends are found for the lower ozone O3 values, with largest negative trend at the easternmost station of IP, and also in northern and mainland stations, and an opposite behaviour, with positive O3 trends, is observed at the Atlantic coast stations.publishe

Les députés européens entre allégeances multiples et logique d'institution

La question de la légitimation dans l'Union européenne présente des aspects très différents selon que l'on envisage ses politiques, ses institutions ou le projet d'intégration lui-même, et se pose en des termes contrastés selon l'angle d'approche adopté. Le présent article a pour objet d'envisager la question du point de vue du Parlement européen et de ses membres. Il examine la manière dont les comportements et discours des parlementaires européens sont conditionnés par l'impératif de légitimation et, inversement, analyse comment cet impératif est redéfini en fonction de l'inclusion des députés dans un réseau d'allégeances complexe et contrasté. L'hypothèse centrale est que la légitimation de leurs positions et décisions est l'une des clés du fonctionnement de l'institution, tant dans ses aspects internes qu'externes.The question of legitimisation in the European Union can be seen in very different lights depending on whether its politics, its institutions or the integration project itself is under scrutiny, and is posed in contrasting terms according to the angle of approach which is adopted. This article aims to envisage the question from the point of view of the European Parliament (EP) and of its members (MEPs). It examines the way in which the behaviour and speech of MEPs are conditioned by the imperative of legitimisation and, conversely, analyses how this imperative is redefined by the inclusion of the MEPs in a network of complex and contrasting allegiances. The central hypothesis is that the legitimisation of their positions and decisions is one of the keys to the functioning of the institution, as much in its internal as in its external aspects

The sacral chordoma margin

Objective: Aim of the manuscript is to discuss how to improve margins in sacral chordoma. Background: Chordoma is a rare neoplasm, arising in half cases from the sacrum, with reported local failure in >50% after surgery. Methods: A multidisciplinary meeting of the \u201cChordoma Global Consensus Group\u201d was held in Milan in 2017, focusing on challenges in defining and achieving optimal margins in chordoma with respect to surgery, definitive particle radiation therapy (RT) and medical therapies. This review aims to report on the outcome of the consensus meeting and to provide a summary of the most recent evidence in this field. Possible new ways forward, including on-going international clinical studies, are discussed. Results: En-bloc tumor-sacrum resection is the cornerstone of treatment of primary sacral chordoma, aiming to achieve negative microscopic margins. Radical definitive particle therapy seems to offer a similar outcome compared to surgery, although confirmation in comparative trials is lacking; besides there is still a certain degree of technical variability across institutions, corresponding to different fields of treatment and different tumor coverage. To address some of these questions, a prospective, randomized international study comparing surgery versus definitive high-dose RT is ongoing. Available data do not support the routine use of any medical therapy as (neo)adjuvant/cytoreductive treatment. Conclusion: Given the significant influence of margins status on local control in patients with primary localized sacral chordoma, the clear definition of adequate margins and a standard local approach across institutions for both surgery and particle RT is vital for improving the management of these patients