LES of an Inclined Jet into a Supersonic Turbulent Crossflow

This short article describes flow parameters, numerical method, and animations of the fluid dynamics video "LES of an Inclined Jet into a Supersonic Turbulent Crossflow" (http://ecommons.library.cornell.edu/bitstream/1813/14073/3/GFM-2009.mpg [high-resolution] and http://ecommons.library.cornell.edu/bitstream/1813/14073/2/GFM-2009-web.m1v [low-resolution] video). We performed large-eddy simulation with the sub-grid scale (LES-SGS) stretched-vortex model of momentum and scalar transport to study the gas-dynamics interactions of a helium inclined round jet into a supersonic ($M=3.6$) turbulent (\Reth$=13\times10^3$) air flow over a flat surface. The video shows the temporal development of Mach-number and magnitude of density-gradient in the mid-span plane, and isosurface of helium mass-fraction and \lam_2 (vortical structures). The identified vortical structures are sheets, tilted tubes, and discontinuous rings. The vortical structures are shown to be well correlated in space and time with helium mass-fraction isosurface ($Y_{\rm He}=0.25$).Comment: 7 pages, 1 figure, 1 table, article describing fluid dynamics video submitted to Gallery of Fluid Motion, APS-DFD 200

Valutazione dell’accessibilità con software open source

L'accessibilità ha da sempre ricoperto un ruolo fondamentale per lo sviluppo delle società e per rendere sempre più agevoli gli spostamenti, a prescindere dalle cause che li originano. In questo articolo si vuole focalizzare l’attenzione sull’accessibilità ai terminal aeroportuali, in quanto la velocità e la facilità di accesso sono aspetti strategici per il trasporto aereo. Se il tempo di accesso ai terminal non fosse sufficientemente rapido, negli spostamenti a breve distanza, l’aereo perderebbe il vantaggio che ha sulle altre scelte modali. Lo scopo che ci si è posti nella ricerca è di valutare l’accessibilità territoriale attraverso l’uso di software GIS (Geographic Information System) open source. Per validare il metodo si è condotta un’applicazione sulle infrastrutture aeroportuali siciliane. A tal fine è stato preliminarmente necessario analizzare la rete stradale siciliana, per creare un quadro generale che ha permesso di mettere in evidenza il grado di accessibilità che caratterizza i tre principali aeroporti dell’isola: · Falcone Borsellino di Palermo-Punta Raisi, · Vincenzo Bellini di Catania-Fontanarossa, · Vincenzo Florio di Trapani-Birgi. Lo studio si è concentrato sulle misure topologiche dell’accessibilità, che esprimono la raggiungibilità di un sito in funzione delle connessioni offerte dal sistema di trasporti. È stata, quindi, considerata l’accessibilità passiva a partire da tutti i comuni siciliani verso i terminal aeroportuali in termini di tempo. Tale misura può essere rappresentata da curve isocrone, che permettono di determinare il numero di destinazioni potenziali che possono essere raggiunte in un prefissato intervallo di tempo di viaggio. Questa misura non tiene conto della percezione degli individui e delle loro preferenze; ciò implica che tutte le opportunità sono egualmente desiderabili con riferimento al tempo di viaggio o al tipo di opportunità. Le isocrone sono state tracciate per testare il potenziale della rete stradale a vuoto e sotto l’ipotesi semplificativa che l’offerta dei tre aeroporti, in termini di voli disponibili, sia uguale

Chapter Determinants of spatial intensity of stop locations on cruise passengers tracking data

This paper aims at analyzing the spatial intensity in the distribution of stop locations of cruise passengers during their visit at the destination through a stochastic point process modelling approach on a linear network. Data collected through the integration of GPS tracking technology and questionnaire-based survey on cruise passengers visiting the city of Palermo are used, to identify the main determinants which characterize their stop locations pattern. The spatial intensity of stop locations is estimated through a Gibbs point process model, taking into account for both individual-related variables, contextual-level information, and for spatial interaction among stop points. The Berman-Turner device for maximum pseudolikelihood is considered, by using a quadrature scheme generated on the network. The approach used allows taking into account the linear network determined by the street configuration of the destination under analysis. The results show an influence of both socio-demographic and trip-related characteristics on the stop location patterns, as well as the relevance of distance from the main attractions, and potential interactions among cruise passengers in stop configuration. The proposed approach represents both improvements from the methodological perspective, related to the modelling of spatial point process on a linear network, and from the applied perspective, given that better knowledge of the determinants of spatial intensity of visitors’ stop locations in urban contexts may orient destination management policy

CD40 ligand and MCP-1 as predictors of cardiovascular events in diabetic patients with stroke

Aim: Up-regulation of soluble CD40 ligand (sCD40L) and of monocyte chemoattractant protein-1 (MCP-1) has been found in diabetes and in patients with acute cerebral ischemia. We asked whether (i) the two molecules are similarly upregulated among non-lacunar and lacunar diabetic strokes and (ii) sCD40L and/or MCP-1 predict the risk of cardiovascular events in this setting.Methods: Ninety patients with type 2 diabetes mellitus presenting with an acute ischemic stroke (compared with 45 control subjects) were evaluated on admission and up to 36 months (median 24 months) after the event.Results: Diabetic patients with acute stroke had higher plasma CD40L and MCP-1 than controls (p<0.0001), with no significant differences among lacunar and non-lacunar strokes. On multiple regres-sion analysis, only higher sCD40L quartiles and older age were associated with higher MCP-1 quar-tiles. Forty-eight percent of patients experienced vascular events. Cox regression analysis showed that only the presence of higher sCD40L values independently predicted the recurrence of vascular events.Conclusion: Up-regulation of inflammatory molecules, such as CD40L and MCP-1, is involved in the advanced stage of atherosclerotic cerebro-vascular disease and is associated with increased risk of recurrence of cardiovascular events.AIM: Up-regulation of soluble CD40 ligand (sCD40L) and of monocyte chemoattractant protein-1 (MCP-1) has been found in diabetes and in patients with acute cerebral ischemia. We asked whether (i) the two molecules are similarly upregulated among non-lacunar and lacunar diabetic strokes and (ii) sCD40L and/or MCP-1 predict the risk of cardiovascular events in this setting. METHODS: Ninety patients with type 2 diabetes mellitus presenting with an acute ischemic stroke (compared with 45 control subjects) were evaluated on admission and up to 36 months (median 24 months) after the event. RESULTS: Diabetic patients with acute stroke had higher plasma CD40L and MCP-1 than controls (p<0.0001), with no significant differences among lacunar and non-lacunar strokes. On multiple regression analysis, only higher sCD40L quartiles and older age were associated with higher MCP-1 quartiles. Forty-eight percent of patients experienced vascular events. Cox regression analysis showed that only the presence of higher sCD40L values independently predicted the recurrence of vascular events. CONCLUSION: Up-regulation of inflammatory molecules, such as CD40L and MCP-1, is involved in the advanced stage of atherosclerotic cerebro-vascular disease and is associated with increased risk of recurrence of cardiovascular events

Bridging aortic valve surgery to 21st century. what can a surgeon do

Aortic valve stenosis is the most clinically relevant valvular heart disease in the elderlies. Surgical aortic valve replacement (SAVR) represented, for decades, the standard of care for the treatment of severe aortic stenosis. Although SAVR still represents a valid option in this clinical scenario, transcatheter aortic valve implantation proved to be superior to medical therapy and comparable to SAVR in several randomized trials in patients at high or intermediate operative risk. At the same time, the growing aging population carrying on greater morbidities and high risk profiles has led to the development of minimally invasive technologies, as rapid deployment aortic valve replacement or Sutureless, to minimize surgical impact on patients. The Heart Team is nowadays tasked to determine the best option tailored for each patient considering patient-related factors and mastering all the surgical options in terms of both different techniques and types of available valves. Nevertheless, some open issues need to be already answered as: which has the longest durability, which the lower complication rate and the lower overall mortality. The aim of this review is to briefly resume the main features of these different options and explore what kind of open questions these newer-generation prosthetic valves and delivery devices carry

Climate Change and Childhood Respiratory Health: A Call to Action for Paediatricians

Climate change (CC) is one of the main contributors to health emergencies worldwide. CC appears to be closely interrelated with air pollution, as some pollutants like carbon dioxide (CO2), nitrogen oxides (NOx) and black carbon are naturally occurring greenhouse gases. Air pollution may enhance the allergenicity of some plants and, also, has an adverse effect on respiratory health. Children are a uniquely vulnerable group that suffers disproportionately from CC burden. The increasing global warming related to CC has a big impact on plants' lifecycles, with earlier and longer pollen seasons, as well as higher pollen production, putting children affected by asthma and allergic rhinitis at risk for exacerbations. Extreme weather events may play a role too, not only in the exacerbations of allergic respiratory diseases but, also, in favouring respiratory infections. Even though paediatricians are already seeing the impacts of CC on their patients, their knowledge about CC-related health outcomes with specific regards to children's respiratory health is incomplete. This advocates for paediatricians' increased awareness and a better understanding of the CC impact on children's respiratory health. Having a special responsibility for children, paediatricians should actively be involved in policies aimed to protect the next generation from CC-related adverse health effects. Hence, there is an urgent need for them to take action and successfully educate families about CC issues. This paper aims at reviewing the evidence of CC-related environmental factors such as temperature, humidity, rainfall and extreme events on respiratory allergic diseases and respiratory infections in children and proposing specific actionable items for paediatricians to deal with CC-related health issues in their clinical practice

Investigating the impact of copper leaching on combustion characteristics and particulate emissions in HPCR diesel engines

© 2019 Elsevier Ltd Copper leaching in diesel fuel and its impact on combustion and emission characteristics of a Direct Injection High Pressure Common Rail (DI HPCR) diesel engine was investigated. This work was performed using a single cylinder Ricardo Hydra research engine fitted with a cylinder head, piston assembly, and crankshaft from a production 2.2 L DI diesel engine. A fuel conditioning device consisting of a helicoidally shaped copper duct and electromagnetic coils powered from the battery was installed along the fuel line just before the high pressure pump. A diesel fuel with a copper content of less than 0.2 ppm was used. Inductively coupled plasma mass spectrometry (ICP-MS) analysis showed an increase of copper content to 1 ppm when fuel flowed through the conditioning device prior to the injection and returned from the engine back to the fuel tank. Copper leaching from the conditioning device was confirmed using a bespoke test rig. Combustion characteristics were analysed via post-processing pressure measurements, while an AVL Smoke Meter was used to monitor particulate emissions. A pilot plus main strategy was used to achieve a target Brake Mean Effect Pressure (BMEP) typical of medium load. Soot reduction in the range of 7–14% was measured when the device was connected to the fuel line, compared to the baseline. The initiation and early development of combustion was also investigated using an unstirred, quiescent combustion chamber with optical access. High-speed photography showed that ignition probability was enhanced in presence of the fuel conditioning device

Acromegaly is associated with increased cancer risk: A survey in Italy

It is debated if acromegalic patients have an increased risk to develop malignancies. The aim of the present study was to assess the standardized incidence ratios (SIRs) of different types of cancer in acromegaly on a large series of acromegalic patients managed in the somatostatin analogs era. It was evaluated the incidence of cancer in an Italian nationwide multicenter cohort study of 1512 acromegalic patients, 624 men and 888 women, mean age at diagnosis 45 \uc2\ub1 13 years, followed up for a mean of 10 years (12573 person-years) in respect to the general Italian population. Cancer was diagnosed in 124 patients, 72 women and 52 men. The SIRs for all cancers was significantly increased compared to the general Italian population (expected: 88, SIR 1.41; 95% CI, 1.18-1.68, P < 0.001). In the whole series, we found a significantly increased incidence of colorectal cancer (SIR 1.67; 95% CI, 1.07-2.58, P = 0.022), kidney cancer (SIR 2.87; 95% CI, 1.55-5.34, P < 0.001) and thyroid cancer (SIR 3.99; 95% CI, 2.32-6.87, P < 0.001). The exclusion of 11 cancers occurring before diagnosis of acromegaly (all in women) did not change remarkably the study outcome. In multivariate analysis, the factors significantly associated with an increased risk of malignancy were age and family history of cancer, with a non-significant trend for the estimated duration of acromegaly before diagnosis. In conclusion, we found evidence that acromegaly in Italy is associated with a moderate increase in cancer risk