Investigation of surface inclination effect during dropwise condensation of flowing saturated steam

When a pure vapor condenses over a surface, it can form a continuous liquid film or a multitude of discrete droplets, thus realizing the so-called dropwise condensation (DWC). In the literature, most of the experimental data refer to DWC on vertical condensing surfaces with quiescent vapor. However, in many applications, the condensing vapor usually has a non-zero flow velocity with a consequent effect on the sliding motion of droplets. Moreover, the drag force due to vapor velocity may be the only mechanism for liquid removal on a horizontal surface or in space applications. A systematic investigation of the effects of vapor drag and surface inclination on the heat transfer and droplet population during DWC is needed and is addressed in the present paper. Here, DWC of flowing steam is experimentally studied on sol-gel silica-based coated aluminium substrates at three different inclinations: vertical, inclined at 45°, and horizontal. Heat transfer coefficient (HTC) and droplet population measurements are performed in a wide range of heat flux (260–610 kW m−2) and average vapor velocity (3.3–13.8 m s−1). When decreasing the tilt angle, from vertical to horizontal, due to the lower contribution of the gravity force, the average droplet size increases, and a strong HTC reduction is observed above all at low vapor velocities. Because of the vapor drag force, the HTC increases with steam velocity and, at the highest mass velocity, the HTC is independent from the surface inclination. A model for the droplet departing radius in the presence of vapor velocity, initially proposed by the present authors for the sole case of vertical surfaces, is here modified to account also for the effect of surface inclination and then assessed against the present experimental data. Hence, we propose to predict the heat flux during DWC by coupling the new equation for the departing radius with the available models of heat transfer through a single droplet and drop-size distribution. The developed calculation method is found to provide satisfactory predictions of the HTC for the whole range of vapor velocity, heat flux and surface inclination

Age-related differences in the expression of circulating microRNAs: miR-21 as a new circulating marker of inflammaging.

none15noopenF Olivieri; L Spazzafumo; G Santini; R Lazzarini; MC Albertini; MR Rippo; R Galeazzi; AM Abbatecola; F Marcheselli; D Monti; R Ostan; E Cevenini; R Antonicelli; C Franceschi; AD Procopio.F., Olivieri; L., Spazzafumo; G., Santini; R., Lazzarini; Albertini, MARIA CRISTINA; Mr, Rippo; R., Galeazzi; Am, Abbatecola; F., Marcheselli; D., Monti; R., Ostan; E., Cevenini; R., Antonicelli; C., Franceschi; Ad, Procopi

Moving against frailty: does physical activity matter?

Frailty is a common condition in older persons and has been described as a geriatric syndrome resulting from age-related cumulative declines across multiple physiologic systems, with impaired homeostatic reserve and a reduced capacity of the organism to resist stress. Therefore, frailty is considered as a state of high vulnerability for adverse health outcomes, such as disability, falls, hospitalization, institutionalization, and mortality. Regular physical activity has been shown to protect against diverse components of the frailty syndrome in men and women of all ages and frailty is not a contra-indication to physical activity, rather it may be one of the most important reasons to prescribe physical exercise. It has been recognized that physical activity can have an impact on different components of the frailty syndrome. This review will address the role of physical activity on the most relevant components of frailty syndrome, with specific reference to: (i) sarcopenia, as a condition which frequently overlaps with frailty; (ii) functional impairment, considering the role of physical inactivity as one of the strongest predictors of physical disability in elders; (iii) cognitive performance, including evidence on how exercise and physical activity decrease the risk of early cognitive decline and poor cognition in late life; and (iv) depression by reviewing the effect of exercise on improving mood and increasing positive well-being

Change of Accent as an Atypical Onset of non Fluent Primary Progressive Aphasia

Language disorders can be the first symptom of many neurodegenerative diseases, including Alzheimer's disease (AD) and primary progressive aphasia (PPA). The main variants of PPA are: the non-fluent/agrammatic variant, the semantic variant and the logopenic variant

Plasma polyunsaturated fatty acids and age-related physical performance decline. Rejuvenation Res

Abstract Due to supporting evidence that dietary patterns may have a significant role in the maintenance of good physical performance with aging, we tested whether plasma fatty acids, saturated fatty acids (SFA), and polyunsaturated (PUFA) fatty acids are cross-sectionally associated with different physical performance and predict changes in physical performance over a 3-year period. Data were from the InCHIANTI study, a populationbased study of older Italians. Plasma fatty acids were measured at enrollment (1998)(1999)(2000), and outcome variables, Summary Physical Performance Battery (SPPB), and time to walk 7 meters (m) were measured at enrollment and after 3 years (2001)(2002)(2003)(2004). At enrollment, 330 participants had significantly impaired lower extremity performance (defined as a SPPB score Յ9). Adjusting for age, participants with a SPPB score Ͼ9 had higher levels of total PUFA, n-3 PUFA, and n-6 PUFA, while significantly lower levels of SFA than those with a SPPB score Ͻ9. Baseline SPPB scores were also associated with n-3 PUFA (␤ ϭ 0.148, p ϭ 0.031), whereas the 7-m walk time was associated with total PUFA (␤ ϭ Ϫ0.068, p ϭ 0.008), after adjusting for potential confounders. Of the 884 participants with a SPPB score Ͼ9 at baseline, 114 (12.9%) developed impaired lower extremity performance (SPPB Յ9). In fully adjusted logistic models, baseline n-3 PUFA levels were inversely related to the risk of developing a decline in SPPB to Յ9 (odds ratio [OR] ϭ 0.21; 95% confidence interval [CI] ϭ 0.08-0.53), while the n-6/n-3 ratio was associated with a higher risk of SPPB decline to Յ9 (OR ϭ 5.23; 95% CI ϭ 2.02-13.51). In multivariate regression models, the n-6/n-3 ratio was associated with a longer time to walk 7 m ( ␤ ϭ 0.396, p ϭ 0.037). n-3 PUFA plasma levels, which most likely reflect dietary intake, seem to protect against accelerated decline of physical performance. A higher n-6/n-3 ratio was associated with higher risk of developing poor physical performance and slower walking speed. 2

Plasma polyunsaturated fatty acids and age-related physical performance decline

Due to supporting evidence that dietary patterns may have a significant role in the maintenance of good physical performance with aging, we tested whether plasma fatty acids, saturated fatty acids (SFA), and polyunsaturated (PUFA) fatty acids are cross-sectionally associated with different physical performance and predict changes in physical performance over a 3-year period. Data were from the InCHIANTI study, a population-based study of older Italians. Plasma fatty acids were measured at enrollment (1998-2000), and outcome variables, Summary Physical Performance Battery (SPPB), and time to walk 7 meters (m) were measured at enrollment and after 3 years (2001-2004). At enrollment, 330 participants had significantly impaired lower extremity performance (defined as a SPPB score 9 had higher levels of total PUFA, n-3 PUFA, and n-6 PUFA, while significantly lower levels of SFA than those with a SPPB score 9 at baseline, 114 (12.9%) developed impaired lower extremity performance (SPPB < or = 9). In fully adjusted logistic models, baseline n-3 PUFA levels were inversely related to the risk of developing a decline in SPPB to < or = 9 (odds ratio [OR] = 0.21; 95% confidence interval [CI] = 0.08-0.53), while the n-6/n-3 ratio was associated with a higher risk of SPPB decline to < or = 9 (OR = 5.23; 95% CI = 2.02-13.51). In multivariate regression models, the n-6/n-3 ratio was associated with a longer time to walk 7 m (beta = 0.396, p = 0.037). n-3 PUFA plasma levels, which most likely reflect dietary intake, seem to protect against accelerated decline of physical performance. A higher n-6/n-3 ratio was associated with higher risk of developing poor physical performance and slower walking speed

Plasma Polyunsaturated Fatty Acids and Age-Related Physical Performance Decline

Due to supporting evidence that dietary patterns may have a significant role in the maintenance of good physical performance with aging, we tested whether plasma fatty acids, saturated fatty acids (SFA), and polyunsaturated (PUFA) fatty acids are cross-sectionally associated with different physical performance and predict changes in physical performance over a 3-year period. Data were from the InCHIANTI study, a population-based study of older Italians. Plasma fatty acids were measured at enrollment (1998–2000), and outcome variables, Summary Physical Performance Battery (SPPB), and time to walk 7 meters (m) were measured at enrollment and after 3 years (2001–2004). At enrollment, 330 participants had significantly impaired lower extremity performance (defined as a SPPB score ≤9). Adjusting for age, participants with a SPPB score >9 had higher levels of total PUFA, n-3 PUFA, and n-6 PUFA, while significantly lower levels of SFA than those with a SPPB score <9. Baseline SPPB scores were also associated with n-3 PUFA (β = 0.148, p = 0.031), whereas the 7-m walk time was associated with total PUFA (β = −0.068, p = 0.008), after adjusting for potential confounders. Of the 884 participants with a SPPB score >9 at baseline, 114 (12.9%) developed impaired lower extremity performance (SPPB ≤9). In fully adjusted logistic models, baseline n-3 PUFA levels were inversely related to the risk of developing a decline in SPPB to ≤9 (odds ratio [OR] = 0.21; 95% confidence interval [CI] = 0.08–0.53), while the n-6/n-3 ratio was associated with a higher risk of SPPB decline to ≤9 (OR = 5.23; 95% CI = 2.02–13.51). In multivariate regression models, the n-6/n-3 ratio was associated with a longer time to walk 7 m (β = 0.396, p = 0.037). n-3 PUFA plasma levels, which most likely reflect dietary intake, seem to protect against accelerated decline of physical performance. A higher n-6/n-3 ratio was associated with higher risk of developing poor physical performance and slower walking speed