Correction: Equilibrium gels of low-valence DNA nanostars: a colloidal model for strong glass formers

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Hypertension in Metabolic Syndrome: Vascular Pathophysiology

Metabolic syndrome is a cluster of metabolic and cardiovascular symptoms: insulin resistance (IR), obesity, dyslipemia. Hypertension and vascular disorders are central to this syndrome. After a brief historical review, we discuss the role of sympathetic tone. Subsequently, we examine the link between endothelial dysfunction and IR. NO is involved in the insulin-elicited capillary vasodilatation. The insulin-signaling pathways causing NO release are different to the classical. There is a vasodilatory pathway with activation of NO synthase through Akt, and a vasoconstrictor pathway that involves the release of endothelin-1 via MAPK. IR is associated with an imbalance between both pathways in favour of the vasoconstrictor one. We also consider the link between hypertension and IR: the insulin hypothesis of hypertension. Next we discuss the importance of perivascular adipose tissue and the role of adipokines that possess vasoactive properties. Finally, animal models used in the study of vascular function of metabolic syndrome are reviewed. In particular, the Zucker fatty rat and the spontaneously hypertensive obese rat (SHROB). This one suffers macro- and microvascular malfunction due to a failure in the NO system and an abnormally high release of vasoconstrictor prostaglandins, all this alleviated with glitazones used for metabolic syndrome therapy

Saharan dust impact in central Italy: An overview on three years elemental data records

In southern European countries, Saharan dust may episodically produce significant increases of PM10, which may also cause the exceedance of the PM10 daily limit value established by the European Directive (2008/50/EC). The detection with very high sensitivity of all the elements that constitute mineral dust makes PIXE technique a very effective tool to assess the actual impact of these episodes. In this work, a review of long-term series of elemental concentrations obtained by PIXE has been accomplished with the aim of identifying the occurrence of Saharan dust transport episodes over long periods in Tuscany and characterising them in terms of composition and impact on PM concentration, tracing back their contribution to the exceedances of the PM10 limit value. The impact of the different Saharan intrusions on PM10 showed a very high variability. During the most intense episodes (which occurred with a frequency of few times per year) the calculated soil dust concentration reached values as high as 25\u201330 \u3bcg m 123, to be compared with background values of the order of 5 \u3bcg m 123. The Saharan dust contribution was decisive to cause the exceedance of the PM10 daily limit value in the 1\u20132% of the days considered in the present work

Assessment of potential source regions of PM2.5 components at a southwestern Mediterranean site

A set of PM 2.5 samples ( n = 121) collected at an urban background location in Elche (in southeastern Spain) from December 2004 to November 2005 was analysed by particle-induced X-ray emission (PIXE) and ion chromatography in order to provide source identification and potential source locations. Positive matrix factorization (PMF) was used to estimate source profiles and their mass contributions. The PMF modelling identified six sources: aged sea salt (9.2%), ammonium sulphate (40.4%), soil dust related to Saharan outbreaks (13.0%), traffic 1 (18.9%), nitrate aerosol and traffic 2 (5.5%) and local soil dust (6.0%). Potential source contribution function (PSCF) was then used to identify potential source locations. Scarce influence from Mediterranean and European regions was found with the exception of the nitrate source, whose potential source areas were northern Italy and eastern France. Primary source regions for the remaining components (ammonium sulphate, soil dust-related to Saharan outbreaks and aged sea salt) with known mass contributions due to long-range transport have a marked Atlantic and North African location, primarily between Morocco and northwestern Algeria. DOI: 10.1111/j.1600-0889.2010.00510.