First measurement of hadronic event shapes in pp collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Macroeconomic challenges of fiscal decentralization in Latin America in the aftermath of the global financial crisis

Incluye Bibliografía

Study of hadronic event-shape variables in multijet final states in pp collisions at root s=7 TeV

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Variability analysis of discrete event series and wavefront patterns in surface electrocardiogram: contributions to psychophysiological and clinical research

The surface electrocardiogram (ECG) is an established diagnostic tool for the detection of abnormalities in the electrical activity of the heart. The interest of the ECG, however, extends beyond the diagnostic purpose. In recent years, studies in cognitive psychophysiology have related heart rate variability (HRV) to memory performance and mental workload. The aim of this thesis was to analyze the variability of surface ECG derived rhythms, at two different time scales: the discrete-event time scale, typical of beat-related features (Objective I), and the “continuous” time scale of separated sources in the ECG (Objective II), in selected scenarios relevant to psychophysiological and clinical research, respectively. Objective I) Joint time-frequency and non-linear analysis of HRV was carried out, with the goal of assessing psychophysiological workload (PPW) in response to working memory engaging tasks. Results from fourteen healthy young subjects suggest the potential use of the proposed indices in discriminating PPW levels in response to varying memory-search task difficulty. Objective II) A novel source-cancellation method based on morphology clustering was proposed for the estimation of the atrial wavefront in atrial fibrillation (AF) from body surface potential maps. Strong direct correlation between spectral concentration (SC) of atrial wavefront and temporal variability of the spectral distribution was shown in persistent AF patients, suggesting that with higher SC, shorter observation time is required to collect spectral distribution, from which the fibrillatory rate is estimated. This could be time and cost effective in clinical decision-making. The results held for reduced leads sets, suggesting that a simplified setup could also be considered, further reducing the costs. In designing the methods of this thesis, an online signal processing approach was kept, with the goal of contributing to real-world applicability. An algorithm for automatic assessment of ambulatory ECG quality, and an automatic ECG delineation algorithm were designed and validated.

[A Swiss multicentric project to improve the prevention of cardiovascular event recurrence after acute coronary syndromes]

Recurrence of cardiovascular events and mortality remain high after acute coronary syndromes. A Swiss multicentric study, "Inflammation and acute coronary syndromes (ACS)--Novel strategies for prevention and clinical managements", is currently underway with the support of the Swiss National Science Foundation. The study includes a clinical research subproject of which the aim is to assess the impact of the ELIPS program (multi-dimEnsionaL prevention Program after acute coronary Syndrome) on the recurrence of cardiovascular events after an ACS. The basic research sub-projects aim to investigate novel cardiovascular risk biomarkers and genetic determinants of recurrence and to study the role of stem cells after an ACS. Another sub-project will evaluate intracoronary imaging techniques and the efficacy of different types of stents.

A Framework for the Automation of Discrete-Event Simulation Experiments

Simulation is an important resource for researchers in diverse fields. However, many researchers have found flaws in the methodology of published simulation studies and have described the state of the simulation community as being in a crisis of credibility. This work describes the project of the Simulation Automation Framework for Experiments (SAFE), which addresses the issues that undermine credibility by automating the workflow in the execution of simulation studies. Automation reduces the number of opportunities for users to introduce error in the scientific process thereby improvingthe credibility of the final results. Automation also eases the job of simulation users and allows them to focus on the design of models and the analysis of results rather than on the complexities of the workflow.

The Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic attack (PERFORM) study: baseline characteristics of the population

BACKGROUND: The Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic attack (PERFORM) study is an international double-blind, randomized controlled trial designed to investigate the superiority of the specific TP receptor antagonist terutroban (30 mg/day) over aspirin (100 mg/day), in reducing cerebrovascular and cardiovascular events in patients with a recent history of ischemic stroke or transient ischemic attack. Here we describe the baseline characteristics of the population. METHODS AND RESULTS: Parameters recorded at baseline included vital signs, risk factors, medical history, and concomitant treatments, as well as stroke subtype, stroke-associated disability on the modified Rankin scale, and scores on scales for cognitive function and dependency. Eight hundred and two centers in 46 countries recruited a total of 19,119 patients between February 2006 and April 2008. The population is evenly distributed and is not dominated by any one country or region. The mean +/- SD age was 67.2 +/- 7.9 years, 63% were male, and 83% Caucasian; 83% had hypertension, and about half the population smoked or had quit smoking. Ninety percent of the qualifying events were ischemic stroke, 67% of which were classified as atherothrombotic or likely atherothrombotic (pure or coexisting with another cause). Modified Rankin scale scores showed slight or no disability in 83% of the population, while the scores on the Mini-Mental State Examination, Isaacs' Set Test, Zazzo's Cancellation Test, and the instrumental activities of daily living scale showed a good level of cognitive function and autonomy. CONCLUSIONS: The PERFORM study population is homogeneous in terms of demographic and disease characteristics. With 19,119 patients, the PERFORM study is powered to test the superiority of terutroban over aspirin in the secondary prevention of cerebrovascular and cardiovascular events in patients with a recent history of ischemic stroke or transient ischemic attack.

Catastrophic Ice Shelf Breakup as the Source of Heinrich Event Icebergs

Heinrich layers of the glacial North Atlantic record abrupt widespread iceberg rafting of detrital carbonate and other lithic material at the extreme-cold culminations of Bond climate cycles. Both internal (glaciologic) and external ( climate) forcings have been proposed. Here we suggest an explanation for the iceberg release that encompasses external climate forcing on the basis of a new glaciological process recently witnessed along the Antarctic Peninsula: rapid disintegrations of fringing ice shelves induced by climate-controlled meltwater infilling of surface crevasses. We postulate that peripheral ice shelves, formed along the eastern Canadian seaboard during extreme cold conditions, would be vulnerable to sudden climate-driven disintegration during any climate amelioration. Ice shelf disintegration then would be the source of Heinrich event icebergs.