Review on the influence of process parameters in incremental sheet forming

Incremental sheet forming (ISF) is a relatively new flexible forming process. ISF has excellent adaptability to conventional milling machines and requires minimum use of complex tooling, dies and forming press, which makes the process cost-effective and easy to automate for various applications. In the past two decades, extensive research on ISF has resulted in significant advances being made in fundamental understanding and development of new processing and tooling solutions. However, ISF has yet to be fully implemented to mainstream high-value manufacturing industries due to a number of technical challenges, all of which are directly related to ISF process parameters. This paper aims to provide a detailed review of the current state-of-the-art of ISF processes in terms of its technological capabilities and specific limitations with discussions on the ISF process parameters and their effects on ISF processes. Particular attention is given to the ISF process parameters on the formability, deformation and failure mechanics, springback and accuracy and surface roughness. This leads to a number of recommendations that are considered essential for future research effort

Analysis of the fluid-dynamic behavior of fluidized and vibrofluidized bed containing glycerol

The fluid-dynamic characteristics of fluidized and vibrofluidized beds of inert particles in liquids are being widely studied by researchers interested in understanding and modeling the paste drying process. In this work characteristic fluid-dynamic curves of pressure drop versus air velocity were obtained for fluidized and vibrofluidized beds with glycerol. Glycerol was used as a standard fluid to simulate a paste in the bed, and "ballotini" glass spheres were used as inert particles. The fluid-dynamic behavior as well as the quality of the fluidization regimes was analyzed through pressure drop versus air velocity curves and visual observation of the flow patterns in the beds. The results indicated that standard deviation curves are a useful tool for gaining an understanding of the fluid-dynamic behavior of a vibrofluidized bed. They allow detection of changes in the fluid-dynamic behavior which were not observed by analyzing only the pressure drop versus air velocity curves. For fluidized beds (G=0.00), it was also observed that analysis of curves of standard deviations of pressure drop may help in the estimation of more accurate values of minimum fluidization velocities

Predictors for Restoration of Normal Left Ventricular Function in Response to Cardiac Resynchronization Therapy Measured at Time of Implantation.

There are no parameters predicting the individual probability of "full response" to cardiac resynchronization therapy (CRT). The aim of this work was to find prognostic factors of full clinical and echocardiographic responses (i.e., 6550\% left ventricular ejection fraction [LVEF] and New York Heart Association class I) after 1 year of CRT. This was a prospective follow-up study that involved 2 hospitals. Patients (n = 75) with advanced heart failure (64 \ub1 9 years of age, 87\% men, LVEF 24 \ub1 7\%) who received CRT were followed for 17 \ub1 9 months. Univariate and multivariate regression analyses were used to identify predictors of full CRT response. A nomogram predicting the individual probability of full CRT response during follow-up was calculated. There were 13 patients with restoration of normal LVEF versus 62 without (mean LVEF 56\% \ub1 5\% vs 31\% \ub1 8\%, respectively, p 75\% probability of restoration of normal LVEF. In conclusion, our nomogram using a combination of cause, baseline QRS width, and degree of QRS shortening in response to CRT allows assessment of individual probability of full response. This observation awaits further confirmation from larger series

Prognostic role of non-sustained ventricular tachycardia detected with remote interrogation in a pacemaker population

Background: Non-sustained ventricular tachycardia (NSVT) can occur asymptomatically and can be incidentally detected in the internal records of pacemakers (PM). The clinical value of NSVT in the population of PM patients is still uncertain. Our aim was to assess the prevalence of NSVT detected by remote PM control, to describe the clinical and demographic characteristics of patients with NSVT, and to assess the prognostic significance of NSVT in terms of both overall and cardiovascular mortality. Methods: Consecutive patients followed with PM remote interrogations from September 2010 to December 2015 were included. The transmissions pertaining to the first 12 months of remote control were analysed and the patients were divided by those presenting NSVT and those without NSVT. The two groups were compared in terms of total mortality and cardiovascular mortality based on the administrative data provided by the regional administration of the Italian National Health System. Results: The prevalence of NSVT in 408 patients (62% males, mean age 75.6; SD 10.6 years old) was 21% in a year. During a mean follow-up duration of 44 months, NSVT did not emerge as independently associated with overall mortality, but was associated with cardiovascular mortality in a competing risk regression model with older age, male gender, diabetes, chronic renal insufficiency, ischemic cardiomyopathy and chronic obstructive pulmonary disease. Conclusions: We show that NSVT episodes recorded by remote control in a PM population are independently associated with cardiovascular mortality with possible implications for risk stratification and therapeutic options

Comorbidities, Cardiovascular Therapies, and COVID-19 Mortality: A Nationwide, Italian Observational Study (ItaliCO)

Background: Italy has one of the world\u2019s oldest populations, and suffered one the highest death tolls from Coronavirus disease 2019 (COVID-19) worldwide. Older people with cardiovascular diseases (CVDs), and in particular hypertension, are at higher risk of hospitalization and death for COVID-19. Whether hypertensionmedicationsmay increase the risk for death in older COVID 19 inpatients at the highest risk for the disease is currently unknown. Methods: Data from 5,625 COVID-19 inpatients were manually extracted from medical charts from 61 hospitals across Italy. From the initial 5,625 patients, 3,179 were included in the study as they were either discharged or deceased at the time of the data analysis. Primary outcome was inpatient death or recovery. Mixed effects logistic regression models were adjusted for sex, age, and number of comorbidities, with a random effect for site. Results: A large proportion of participating inpatients were 65 years old (58%), male (68%), non-smokers (93%) with comorbidities (66%). Each additional comorbidity increased the risk of death by 35% [adjOR = 1.35 (1.2, 1.5) p < 0.001]. Use of ACE inhibitors, ARBs, beta-blockers or Ca-antagonists was not associated with significantly increased risk of death. There was a marginal negative association between ARB use and death, and a marginal positive association between diuretic use and death. Conclusions: This Italian nationwide observational study of COVID-19 inpatients, the majority of which 65 years old, indicates that there is a linear direct relationship between the number of comorbidities and the risk of death. Among CVDs, hypertension and pre-existing cardiomyopathy were significantly associated with risk of death. The use of hypertension medications reported to be safe in younger cohorts, do not contribute significantly to increased COVID-19 related deaths in an older population that suffered one of the highest death tolls worldwide

Le competenze matematiche per l\u2019identit\ue0, l\u2019autonomia, la cittadinanza

La matematica, intesa come un complesso organico e coerente di conoscenze, pu\uf2 aiutare lo sviluppo globale della personalit\ue0 dello studente, nell'ottica della formazione alla cittadinanza. Numerose le ricerche, le esperienze didattiche e le riflessioni riportate che documentano la possibilit\ue0 di rispondere con competenza ed efficacia alle difficolt\ue0 di apprendimento di allievi con o senza disabilit\ue0