196 research outputs found

    On Morphic Actions and Integrability of LA-Groupoids

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    Lie theory for the integration of Lie algebroids to Lie groupoids, on the one hand, and of Poisson manifolds to symplectic groupoids, on the other, has undergone tremendous developements in the last decade, thanks to the work of Mackenzie-Xu, Moerdijk-Mrcun, Cattaneo-Felder and Crainic-Fernandes, among others. In this thesis we study - part of - the categorified version of this story, namely the integrability of LA-groupoids (groupoid objects in the category of Lie algebroids), to double Lie groupoids (groupoid objects in the category of Lie groupoids) providing a first set of sufficient conditions for the integration to be possible. Mackenzie's double Lie structures arise naturally from lifting processes, such as the cotangent lift or the path prolongation, on ordinary Lie theoretic and Poisson geometric objects and we use them to study the integrability of quotient Poisson bivector fields, the relation between "local" and "global" duality of Poisson groupoids and Lie theory for Lie bialgebroids and Poisson groupoids.Comment: Ph.D. Thesis, 14+iv+137 Page

    Effetti della pandemia da covid-19 e della Didattica a Distanza (DAD) sulle abilità di lettura in bambini normo-lettori

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    Due to covid-19 pandemic, in February 2020 Italian government decided to take action in order to reduce physical contact and contain the spread of the virus; among the other measures, face-to-face teaching was suspended. All along 2020 and for the major part of 2021 online teaching replaced face-to-face teaching. Teachers and parents were unprepared for this kind of didactic activities and online modality varied during the lockdown months and among different schools.  Different studies analyzed the outcome of these online modalities, mostly on pathological samples (Baschenis et al., 2021).  We conducted a longitudinal study in order to investigate whether online teaching had a negative effect on reading skills development in Italian children typical readers. We recruited forty-nine children from a primary school in Alessandria (Piedmont, Italy) and assessed their reading skills before (T1) and after (T2) covid-19 pandemic. All children with learning disabilities, cognitive and sensory impairments were excluded from our sample. Children attended third grade at T1 and fifth grade at T2. We evaluated reading speed, accuracy and comprehension; data from existing literature has been used to confront our sample with the population of children typical readers. We compared the results obtained at T1 and T2; our findings show that our sample reached the expected improvement in reading fluency. The subjects obtained a significant improvement in reading comprehension as well, but existing data are insufficient to determine if the improvement reached by our sample is the same as expected. Therefore, we can state that online teaching has not worsened reading skills development in typical readers

    Extra virgin olive oil and cardiovascular diseases: benefits for human health

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    The cardioprotective properties of Mediterranean Diet were demonstrated for the first time from the Seven Country Study. In the last few decades, numerous epidemiological studies, as well as intervention trial, confirmed this observation, pointing out the close relationship between the Mediterranean diet and cardiovascular diseases. In this context, extra virgin olive oil (EVOO), the most representative component of this diet, seems to be relevant in lowering the incidence of cardiovascular events, including myocardial infarction and stroke. From a chemical point of view, 98-99% of the total weight of EVOO is represented by fatty acids, especially monounsaturated fatty acids such as oleic acid. Tocopherols, polyphenols and other minor constituents represent the remaining 1-2%. All these components may potentially contribute to "health maintenance" with their beneficial effects by EVOOO

    Correlation between US-PSV and 64-Row MDCTA with Advanced Vessel Analysis in the Quantification of 50–70% Carotid Artery Stenosis

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    Purpose. To correlate ultrasonographic peak systolic velocity (US-PSV) and 64-row multidetector computed tomography angiography (MDCTA) with advanced vessel analysis (AVA) software in the quantification of 50–70% carotid artery stenosis. Materials and methods. 199 consecutive patients (247 arteries) with internal carotid artery (ICA) or third proximal bifurcation stenosis. Each patient was studied by duplex US (DUS) and 64-row MDCTA with AVA software. Results. DUS showed PSV measurements less than 125 cm/s in 51 carotid stenosis and a value greater than this in 196 arteries. 64-row MDCTA AVA software showed a grade of stenosis less than 50% in 42 carotid arteries while a greater 70% was found in 4 carotid arteries; then, carotid arteries with stenosis percentage between 50% and 70% were 201. Linear regression analysis showed a good linear correlation (r = 0.88) between MDCTA-AVA software percentage stenosis and PSV: between 50% grade of stenosis and PSV value corresponding to 133,6 cm/sec and between 70% stenosis and PSV value corresponding to 268 cm/sec. The sensitivity, specificity, positive predictive value(PPV), negative predictive value(NPV) of this analysis were 93%, 82%, 97%, 75%, respectively. Conclusion. Linear correlation between PSV data and grade of stenosis from 50% to 70% obtained with 64-row MDCTA AVA software. Main PSV value corresponding to 50% and 70% grade of stenosis at AVA analysis

    Seasonal pattern of vitamin D in male elite soccer players

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    The phopho-calcium metabolism and the maintenance of bone mass is not the only important role vitamin Dplays. Vitamin D is also known for its anti-inflammatory function and for modulating the immune defence system. The vitamin D deficit is to be referred not simply to a bone tissue worsening, but to cardiovascular diseases, various types of tumours and some autoimmune diseases. In the sport life, a vitamin D deficit is often related to muscular problems, neuromuscular pains, predisposition to injuries, and can affect one’s performance. Since indoor athletes have reduced exposition to sun rays, they are more likely to be subjected to these risks than outdoor athletes. However, in soccer, the athletes can experience vitamin D deficit not just during the winter but in other periods too, most likely due to several reasons such as, dark complexion, coming from high altitude championships, injuries, or inadequate exposition to sun rays during the summer. The purpose of this study was to examine the vitamin D shortage and BMC variations in Italian Serie A elite male soccer player
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