191 research outputs found

    Bi-Hamiltonian Aspects of a Matrix Harry Dym Hierarchy

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    We study the Harry Dym hierarchy of nonlinear evolution equations from the bi-Hamiltonian view point. This is done by using the concept of an S-hierarchy. It allows us to define a matrix Harry Dym hierarchy of commuting Hamiltonian flows in two fields that projects onto the scalar Harry Dym hierarchy. We also show that the conserved densities of the matrix Harry Dym equation can be found by means of a Riccati-type equation.Comment: Revised version, 22 pages; a section on reciprocal transformations added. To appear in J. Math. Phys

    FF-manifolds and integrable systems of hydrodynamic type

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    We investigate the role of Hertling-Manin condition on the structure constants of an associative commutative algebra in the theory of integrable systems of hydrodynamic type. In such a framework we introduce the notion of F-manifold with compatible connection generalizing a structure introduced by Manin.Comment: LaTeX, 21 pages; Sections 5 and 6 completely rewritte

    A 3-component extension of the Camassa-Holm hierarchy

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    We introduce a bi-Hamiltonian hierarchy on the loop-algebra of sl(2) endowed with a suitable Poisson pair. It gives rise to the usual CH hierarchy by means of a bi-Hamiltonian reduction, and its first nontrivial flow provides a 3-component extension of the CH equation.Comment: 15 pages; minor changes; to appear in Letters in Mathematical Physic

    Adherence to Mediterranean Diet and its main determinants in a sample of Italian adults: results from the ARIANNA cross-sectional survey

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    Introduction: Over the last years, many Mediterranean countries, including Italy, have witnessed a shift away from the Mediterranean Diet, thus contributing to the high rates of overweight and obesity. The survey "Adherence to Mediterranean Diet in Italy (ARIANNA)" aimed to evaluate the Adherence to Mediterranean Diet (AMD) and its main determinants in the Italian population. Materials and methods: This study started on March 2023 and was addressed to adults aged >= 17 years, born and resident in Italy, proficient in Italian. Data are collected electronically through a voluntary, anonymous and self-administered questionnaire on the project website. Univariate and then multivariate logistic regressions were performed to evaluate associations between AMD and demographic characteristics, socio-economic status, health status, and lifestyle. Results: On a total of 3,732 completed questionnaires, the 87.70% of the respondents was female and the 71.28% was 17-40 years old. The 83.82% of the respondents had medium AMD, 11.33% low and only 4.85% high. The multivariate analysis revealed that being male (p 40 years (p < 0.05), workers (p <= 0.001), and unemployed (p < 0.05), determined the probability of having a lower AMD. Vegans and vegetarian's diets positively contributed to a higher AMD (p < 0.001). Discussion: These results highlighted a medium AMD in the Italian adult participants and suggested the necessity to implement tailored public health intervention strategies to improve food habits

    Clinical characteristics and prognostic impact of atrial fibrillation in patients with chronic heart failure

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    AIMS: To assess the prevalence, clinical characteristics and independent prognostic impact of atrial fibrillation (AF) in chronic heart failure (CHF) patients, and the potential protective effect of disease-modifying medications, particularly beta-blockers (BB). METHODS: We retrospectively reviewed the charts of patients referred to our center since January 2004, and collected all clinical information available at their first visit. We assessed mortality to the end of June 2015. We compared patients with and without AF, and assessed the association between AF and all-cause mortality by multivariate Cox regression and Kaplan-Meyer analysis, particularly accounting for ongoing treatment with BB. RESULTS: A total of 903 patients were evaluated (mean age 68\ub112 years, 73% male). Prevalence of AF was 19%, ranging from 10% to 28% in patients 6460 and 6577 years, respectively. Besides the older age, patients with AF had more symptoms (NYHA II-III 60 vs. 44%), lower prevalence of dyslipidemia (23 vs. 37%), coronary artery disease (28 vs. 52%) and left bundle branch block (9 vs. 16%). On the contrary, they more frequently presented with an idiopathic etiology (50 vs. 24%), a history of valve surgery (13 vs. 4%) and received overall more devices implantation (31% vs. 21%). The use of disease-modifying medications (i.e. BB and ACE inhibitors/angiotensin receptor blockers) was lower in patients with AF (72 vs. 80% e 71 vs. 79%, respectively), who on the contrary were more frequently treated with symptomatic and antiarrhythmic drugs including diuretics (87 vs. 69%) and digoxin (51 vs. 11%). At a mean follow-up of about 5 years, all-cause mortality was significantly higher in patients with AF as compared to those in sinus rhythm (45% vs. 34%, p value &lt;0.05 for all previous comparisons). However, in a multivariate analysis including the main significant predictors of all-cause mortality, the univariate relationship between AF and death (HR 1.49, 95% CI 1.15-1.92) became not statistically significant (HR 0.98, 95% CI 0.73-1.32). Nonetheless, patients with AF not receiving BB treatment were found to have the worst prognosis, followed by patients with sinus rhythm not receiving BB therapy and patients with AF receiving BB therapy, who both had similarly worse survival when compared to patients with sinus rhythm receiving BB therapy. CONCLUSIONS: AF was highly prevalent and associated with older age, worse clinical presentation and underutilization of disease-modifying medications such as BB in a population of elderly patients with CHF. AF had no independent impact on mortality, but the underutilization of BB in this group of patients was associated to a worse long-term prognosis

    Progetto Regionale: Stima di prevalenze ed incidenza dell\u27uso ed abuso di alcol e di sostanze illecite nella Regione Veneto. Rapporto anno 2005

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    Report on the state of legal and illegal substances use in the territory of Veneto Region.Il Report analizza il fenomeno delle dipendenze nel territorio della Regione Veneto. La descrizione del fenomeno si sviluppa intorno all\u27analisi degli indicatori individuati dall\u27Osservatorio Europeo delle Dipendenze di Lisbona (OEDT): 1-uso di sostanze nella popolazione generale (questo indicatore va a rilevare i comportamenti nei confronti di alcol e sostanze psicoattive da parte della popolazione generale); 2-prevalenza d\u27uso problematico delle sostanze psicoattive; 3-domanda di trattamento degli utilizzatori di sostanze; 4-mortalit? degli utilizzatori di sostanze; 5-malattie infettive. Altri due importanti indicatori che si stanno sviluppando, e che vengono qui illustrati, sono l\u27analisi delle Schede di Dimissione Ospedaliera (SDO) e gli indicatori relativi alle conseguenza sociali dell\u27uso di droghe (criminalit? droga correlata). Inoltre sono state applicate diverse metodologie standard di stima sia per quantificare la quota parte sconosciuta di utilizzatori di sostanze che non afferiscono ai servizi, sia per identificarne alcune caratteristiche

    Validated Prognostic Scores to Predict Outcomes in ECLS-Bridged Patients to Lung Transplantation

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    Selection of patients who may benefit from extracorporeal life support (ECLS) as a bridge to lung transplant (LTx) is crucial. The aim was to assess if validated prognostic scores could help in selecting patients who may benefit from ECLS-bridging predicting their outcomes. Clinical data of patients successfully ECLS-bridged to LTx from 2009 to 2021 were collected from two European centers. For each patient, we calculated Sequential Organ Failure Assessment (SOFA), Simplified Acute Physiology Score III (SAPS III), Acute Physiology and Chronic Health Evaluation II (APACHE II), before placing ECLS support, and then correlated with outcome. Median values of SOFA, SAPS III, and APACHE II were 5 (IQR 3-9), 57 (IQR 47.5-65), and 21 (IQR 15-26). In-hospital, 30 and 90 days mortality were 21%, 14%, and 22%. SOFA, SAPS III, and APACHE II were analyzed as predictors of in-hospital, 30 and 90 days mortality (SOFA C-Index: 0.67, 0.78, 0.72; SAPS III C-index: 0.48, 0.45, 0.51; APACHE II C-Index: 0.49, 0.45, 0.52). For SOFA, the score with the best performance, a value ≥9 was identified to be the optimal cut-off for the prediction of the outcomes of interest. SOFA may be considered an adequate predictor in these patients, helping clinical decision-making. More specific and simplified scores for this population are necessary
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