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© Springer-Verlag 2006. This work was supported by the Spanish Ministry of Science and Technology (MCYT), under grant REN2002-04558-C04-04., This paper reports a cloud cover analysis of cut-off low pressure systems (COL) using a pattern recognition method applied to IR and VIS bispectral histograms. 35 COL occurrences were studied over five years (1994-1998). Five cloud types were identified in COLs, of which high clouds (HCC) and deep convective clouds (DCC) were found to be the most relevant to characterize COL systems, though not the most numerous. Cloud cover in a COL is highly dependent on its stage of development, but a higher percentage of cloud cover is always present in the frontal zone, attributable due to higher amounts of high and deep convective clouds. These general characteristics are most marked during the first stage (when the amplitude of the geopotencial wave increases) and second stage (characterized by the development of a cold upper level low), closed cyclonic circulation minimizing differences between rearward and frontal zones during the third stage. The probability of heavy rains during this stage decreases considerably. The centres of mass of high and deep convective clouds move towards the COL-axis centre during COL evolution., Spanish Ministry of Science and Technology (MCYT), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

© Springer-Verlag 2006. This work was supported by the Spanish Ministry of Science and Technology (MCYT) under Grant REN2002-04558-C04-01=02=03=04 and by the Galician Programme of Research and Development under Grant GIDIT03PXIC38301PN. This work was supported also during three months by a postdoctoral fee from the University of Vigo, Spain (Programa de axudas a mobilidade dos investigadores; Convocatoria de axudas para investigación 2005). We thank also two anonymous reviewers whose comments help us to improve the initial manuscript., An earlier developed multidecadal database of Northern Hemisphere cut-off low systems (COLs), covering a 41 years period (from 1958 to 1998) is used to study COLs interannual variability in the European sector (25 degrees-47.5 degrees N, 50 degrees W-40 degrees E) and the major factors controlling it. The study focus on the influence on COLs interannual variability, of larger scale phenomena such as blocking events and other main circulation modes defined over the Euro-Atlantic region. It is shown that there is a very large interannual variability in the COLs occurrence at the annual and seasonal scales, although without significant trends. The influence of larger scale phenomena is seasonal dependent, with the positive phase of the NAO favoring autumn COL development, while winter COL occurrence is mostly related to blocking events. During summer, the season when more COLs occur, no significant influences were found., Spanish Ministry of Science and Technology (MCYT), Galician Programme of Research and Development, University of Vigo, Spain, Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub

(1) Background: Atrial cardiomyopathy constitutes an intrinsically prothrombotic atrial substrate that may promote atrial fibrillation and thromboembolic events, especially stroke, independently of the arrhythmia. Atrial reservoir strain is the echocardiography marker with the most robust evidence supporting its prognostic utility. The main aim of this study is to identify atrial cardiomyopathy by investigating the association between left atrial dysfunction in echocardiography and P-wave abnormalities in the surface electrocardiogram. (2) Methods: This is a community-based, multicenter, prospective cohort study. A randomized sample of 100 patients at a high risk of developing atrial fibrillation were evaluated using diverse echocardiography imaging techniques, and a standard electrocardiogram. (3) Results: Significant left atrial dysfunction, expressed by a left atrial reservoir strain < 26%, showed a relationship with the dilation of the left atrium (p < 0.001), the left atrial ejection fraction < 50% (p < 0.001), the presence of advanced interatrial block (p = 0.032), P-wave voltage in lead I < 0.1 mV (p = 0.008), and MVP ECG score (p = 0.036). (4) Conclusions: A significant relationship was observed between left atrial dysfunction and the presence of left atrial enlargement and other electrocardiography markers; all of them are non-invasive biomarkers of atrial cardiomyopathy.