STUDIO SPERIMENTALE SUL RISALTO IDRAULICO FORZATO IN ALVEO ORIZZONTALE SCABRO

Si presenta sovente il problema della dissipazione dell’energia della corrente in regime supercritico. A valle di certe opere idrauliche il flusso liquido dispone di un’energia molto elevata tale da creare pronunciati fenomeni di erosione, di scalzamento del letto di fondo e, talvolta, gravi danni alle strutture. Risulta quindi di grande importanza trasformare la corrente da supercritica a subcritica, così da avere un’elevata dissipazione di energia ed un contenimento spaziale della zona di transizione; a tal proposito riveste notevole interesse lo studio del risalto idraulico. Come è noto, infatti, il risalto idraulico grazie ai micro vortici, alle turbolenze ed ai moti secondari all’interno del rullo, dissipa in calore una notevole quantità dell’energia posseduta dalla corrente veloce; proprio per tale comportamento, ha trovato la sua più importante applicazione nei dissipatori di energia. La localizzazione del risalto idraulico è un problema che finora non ha trovato univoche soluzioni, data la sua instabilità spaziale. Da un punto di vista teorico il centro del risalto avviene in corrispondenza della sezione in cui la spinta totale della corrente veloce di monte uguaglia la spinta totale della corrente lenta di valle. La posizione, pertanto, dipende congiuntamente dalle condizioni di valle della corrente lenta e dalle condizioni di monte della corrente veloce; una piccola variazione di una o di entrambe, influenza notevolmente la posizione e la stabilità. Per raggiungere l’obiettivo sono stati usati vari accorgimenti, quali salti, gradini e soglie di fondo, macro scabrezze (come i denti di Rehbock), controbriglie, bruschi allargamenti di sezione, fondo acclive o declive. Il presente lavoro, di carattere teorico-sperimentale, indaga il fenomeno del risalto idraulico su fondo orizzontale scabro con l’ausilio di soglia di fondo. In letteratura sono presenti studi riguardanti il risalto idraulico su fondo orizzontale ma liscio, sia con soglia di fondo che senza

Libertà personale e doppio binario processuale: una difficile convivenza

La tesi concerne la relazione tra la libertà personale e le peculiari esigenze processuali attinenti a reati di particolare gravità, tra cui , in specifico, la criminalità organizzata. Ho voluto evidenziare come lo Stato ha cercato di reagire, attraverso numerosi interventi legislativi, alle peculiarità della suddetta fattispecie criminosa, cercando di inserire specifiche regole processuali collimanti con i principi costituzionali in materia. La tesi, quindi, dapprima, affronta l'analisi dei principi costituzionali rilevanti in materia di libertà personale, poi si sofferma sulle modifiche processuali introdotte, concentrandosi soprattutto sulle peculiarità in materia di misure cautelari personali. La trattazione si è soffermata, infine, sulle numerose pronunce delle supreme corti inerenti alle modifiche legislative concernenti il regime delle misure cautelari personali applicabili ai reati di particolare gravità, al fine di ridurne la portata operativa

Comparison Of Ceres-Modis Derived Polar Cloud Properties With Cloudsat/calipso And Ground-Based Measurements

Passive satellites often face difficulty when detecting clouds over snow and ice covered surfaces beneath them. The recent launches of active satellites, which directly measure cloud properties, have allowed scientists to gain a firsthand look at the complex cloud profiles across polar regions. To help quantify the differences between passive and active satellite retrievals, cloud properties derived for the Clouds and Earth\u27s Radiant Energy System (CERES) project using MODerate Resolution Imaging Spectroradiometer (MODIS) data are compared with combined measurements from Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and CloudSat (CC), and Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) observations at the North Slope of Alaska site, from July 2006 to June 2010. The study was then extended to include the entire Arctic and Antarctic. During the 4-year period, monthly mean cloud fractions (CFs) between ARM and CC differ by 5%. While CERES-MODIS CF retrievals agree well with ARM and CC during warm months (May-October), retrievals during the cold season (November-April) significantly underestimate CF. Annual mean cloud-base heights derived from ARM and CC agree within 200 m, while their cloud-top heights (Htop) differ by an average of 1.2 km, due largely to CC detecting more upper-level clouds during the warm months. Effective cloud heights from CERES-MODIS retrievals fall between CC and ARM cloud bases and tops, as expected. Cloud fractions and heights across the span of the Arctic depict similar features as those shown at the ARM NSA site. During summer months, cloud fractions between CERES-MODIS and CC agree well, differing by no more than 10% across most regions of the Arctic. During this same season, however, cloud heights vary by as much as 5.2 km. This is largely due to multi-layer cloud systems, where CC measures the uppermost cloud layer, and CERES-MODIS detects lower cloud layers, resulting in lower CERES-MODIS cloud heights, but equal cloud fractions. Winter shows a contrast to the similarities in cloud fraction detected in summer, with CERES-MODIS underestimating CF by as much as 59%. Cloud heights between the two platforms, however, show better agreement during the cold months, when fewer high clouds occur. The largest differences in CERES-MODIS and CC cloud fractions and heights occur during the cold season (JJA) in the Antarctic. During this time period, CC detects cloud fractions as much as 43% higher than CERES-MODIS, over regions coupled with cloud heights up to 12.3 km higher than CERES-MODIS. These extreme differences are caused by the presence of polar stratospheric clouds, which occur at altitudes between 15 and 25 km, and are nearly impossible for the CERES-MODIS sensor to detect. Finally, single-layered low-level stratus cloud effective radius (re), liquid water path (LWP), and optical depth (τ) retrieved from CERES-MODIS and surface-based retrievals at the ARM NSA site were investigated. When surface snow and sea ice are not present, ARM and CERES-MODIS retrieved cloud droplet re, LWP, and τ agree well. However, when snow and sea ice are introduced, CERES-MODIS retrieved re values are higher than ARM results, while optical depths are lower. These differences suggest that CERES-MODIS cloud fraction retrieval algorithms during polar night and microphysical retrieval algorithms over snow and ice covered surfaces need future improvement

Gli opuscoli del fondo Bellini Pietri della Biblioteca di storia delle arti di Pisa dal 1867 al 1877

In questa tesi si catalogano e si descrivono gli opuscoli del Fondo Bellini Pietri della Biblioteca di Storia delle Arti di Pisa dal 1867 al 1877. Il lavoro svolto ha comportato una prima fase di riorganizzazione del materiale a cui è seguita la catalogazione. Per quanto riguarda le intestazioni, le norme usate sono state le RICA; mentre per la descrizione delle schede si è fatto riferimento all’ISBD(M). Per avere un riscontro degli opuscoli a livello nazionale, sono stati consultati vari repertori bibliografici. Gli opuscoli trattano i temi fondamentali dell’arte, dell’architettura e della pittura, ma danno molto spazio alla storia e alla cultura locale e più in generale toscana. Troviamo infatti pubblicazioni che riportano essenzialmente notizie legate alla situazione politica di Pisa, alla storia dell’Università, a manifestazioni e celebrazioni tenutesi nella città stessa, sono presenti inoltre pubblicazioni per nozze e necrologi di personaggi pisani o toscani e biografie di personaggi toscani. Non mancano comunque pubblicazioni più in generale italiane e alcune pubblicazioni straniere

Paisagem cultural das Missões Jesuíticas Guaranis: o desafio de promover uma leitura patrimonial da paisagem

Em 80 anos de atuação no âmbito da política do patrimônio cultural brasileiro, novos desafios cada vez mais complexos põem em xeque a capacidade de resposta do Instituto do Patrimônio Histórico e Artístico Nacional – Iphan. Neste caso, trata-se de compreender o território das missões jesuíticas brasileiras no Estado do Rio Grande do Sul em abordagem sistêmica e multiétnica, respeitando e valorizado as suas referências e tradições culturais, e tendo em vista a sua preservação e o desenvolvimento local. O Projeto de Valorização da Paisagem Cultural e do Parque Histórico Nacional das Missões Jesuíticas dos Guaranis, lançado em agosto de 2014, vem precisamente trabalhar na perspectiva da articulação gradativa de gestores e atores locais e no fomento de ações de desenvolvimento social. Visa ao conhecimento e à caracterização de sua paisagem cultural e à criação de instrumentos de gestão do território do Parque Histórico Nacional das Missões.En 80 años de operación de la política del patrimonio cultural brasileño, nuevos retos cada vez más complejos ponen en jeque la capacidad de respuesta del Instituto Histórico Artístico Nacional - IPHAN. En este caso, se trata de entender el territorio de las misiones jesuíticas brasileñas de Río Grande do Sul, en abordaje sistemática y multiétnica, respetando y valorando sus referencias culturales y tradiciones, y con miras a su conservación y desarrollo local. El Proyecto de Valorización del Paisaje Cultural y del Parque Histórico Nacional de Misiones Jesuíticas de los Guaraníes, lanzado en agosto de 2014, va precisamente trabajar hacia la articulación progresiva de los gestores y actores locales y la promoción de acciones de desarrollo social. Visa al conocimiento y caracterización de su paisaje cultural y a la creación de instrumentos de gestión del territorio del Parque Histórico Nacional de Misiones.In 80 years of operation of the policy of the Brazilian cultural heritage, new challenges of increasing complexity call into question the responsiveness of the National Historical and Artistic Heritage Institute - Iphan. In this case, the question is to understand the territory of Brazilian Jesuit Missions in Rio Grande do Sul through a systematic and multi-ethnic approach, respecting and valuing their cultural references and traditions, with a view to their preservation and local development. The Project of Valorization of the Cultural Landscape and the National Historic Park of Jesuit Missions of the Guarani, launched in August 2014, precisely works towards the gradual articulation of managers and local stakeholders and the promotion of social development actions. Aims the knowledge and the characterization of its cultural landscape and the creation of land management instruments for the National Historic Park of Jesuit Missions.Peer Reviewe

Paisagem cultural das Missões Jesuíticas Guaranis: o desafio de promover uma leitura patrimonial da paisagem

Em 80 anos de atuação no âmbito da política do patrimônio cultural brasileiro, novos desafios cada vez mais complexos põem em xeque a capacidade de resposta do Instituto do Patrimônio Histórico e Artístico Nacional – Iphan. Neste caso, trata-se de compreender o território das missões jesuíticas brasileiras no Estado do Rio Grande do Sul em abordagem sistêmica e multiétnica, respeitando e valorizado as suas referências e tradições culturais, e tendo em vista a sua preservação e o desenvolvimento local. O Projeto de Valorização da Paisagem Cultural e do Parque Histórico Nacional das Missões Jesuíticas dos Guaranis, lançado em agosto de 2014, vem precisamente trabalhar na perspectiva da articulação gradativa de gestores e atores locais e no fomento de ações de desenvolvimento social. Visa ao conhecimento e à caracterização de sua paisagem cultural e à criação de instrumentos de gestão do território do Parque Histórico Nacional das Missões.En 80 años de operación de la política del patrimonio cultural brasileño, nuevos retos cada vez más complejos ponen en jeque la capacidad de respuesta del Instituto Histórico Artístico Nacional - IPHAN. En este caso, se trata de entender el territorio de las misiones jesuíticas brasileñas de Río Grande do Sul, en abordaje sistemática y multiétnica, respetando y valorando sus referencias culturales y tradiciones, y con miras a su conservación y desarrollo local. El Proyecto de Valorización del Paisaje Cultural y del Parque Histórico Nacional de Misiones Jesuíticas de los Guaraníes, lanzado en agosto de 2014, va precisamente trabajar hacia la articulación progresiva de los gestores y actores locales y la promoción de acciones de desarrollo social. Visa al conocimiento y caracterización de su paisaje cultural y a la creación de instrumentos de gestión del territorio del Parque Histórico Nacional de Misiones.In 80 years of operation of the policy of the Brazilian cultural heritage, new challenges of increasing complexity call into question the responsiveness of the National Historical and Artistic Heritage Institute - Iphan. In this case, the question is to understand the territory of Brazilian Jesuit Missions in Rio Grande do Sul through a systematic and multi-ethnic approach, respecting and valuing their cultural references and traditions, with a view to their preservation and local development. The Project of Valorization of the Cultural Landscape and the National Historic Park of Jesuit Missions of the Guarani, launched in August 2014, precisely works towards the gradual articulation of managers and local stakeholders and the promotion of social development actions. Aims the knowledge and the characterization of its cultural landscape and the creation of land management instruments for the National Historic Park of Jesuit Missions.Peer Reviewe

Small sinkhole-like features in alluvial plains: the example of Paganico (Lucca Plain, Italy)

Paganico is a little village located in the southeastern portion of the Lucca Plain (northwestern Tuscany, Italy). Since the seventies, a few square kilometers' area around Paganico has been involved in the opening of small cavities (sinkhole-like) on the land surface. At the beginning they were very small and sporadic. Later on the phenomena were characterized by a significant extension, increasing in frequency and size (up to 2 m in diameter and depth), causing inconvenience to local people, agricultural operations and occasionally a little damage (cracks to buildings, fencing walls and outside floorings). <br><br> The cavities prevalently occur at the end of the dry season, during or immediately after the first intense rainy events, that is, between the end of summer and early autumn. Even so, the predisposition and triggering causes at present are not completely clarified. Therefore this study is aimed at individuating the triggering and evolution mechanism of the Paganico sinkhole-like features, particularly referring to the stratigraphic, hydrogeological and geotechnical features of the involved materials. <br><br> Another important issue made clear with this research is represented by the overexploitation of the local aquifer, characterized by particular hydro-structural conditions. In fact, the Paganico underground shows three horizons with different lithologic, hydrogeological and geotechnical properties: a superficial silty-sandy horizon (2–3 m thick), which is particularly involved in collapses; an intermediate silty-clayey horizon (2–4 m thick); and a lower and thick gravel-pebbly horizon, characterized by important water resources and heavy pumping. Since the seventies, such water pumping rose considerably due to the local demographic (well field), industrial (paper manufacture) and agricultural development. <br><br> From a hydrogeological point of view, this area is consequently characterized by two water tables: a temporary one, housed in the superficial silty-sandy horizon (perched aquifer), and a second one, confined, associated with the lower gravel-pebbly horizon (aquifer). The perched aquifer and confined aquifer are separated by an impermeable silty-clayey horizon. According to the observations resulting from this study, the latter probably tends to fracture by desiccation during the dry season, originating water exchange between the two water tables during the first important autumnal rainfall, depending on the pumping conditions, which lower the piezometric surface of the confined aquifer. Cracking would also characterize the superficial horizon. Thus, the water exchange would produce erosional phenomena in the superficial material, with removal of the fine fraction and collapse. This process could be at the origin of the cavities opening

Critical rainfall thresholds for triggering shallow landslides in the Serchio River Valley (Tuscany, Italy)

Abstract. The Serchio River Valley, in north-western Tuscany, is a well-known tourism area between the Apuan Alps and the Apennines. This area is frequently hit by heavy rainfall, which often triggers shallow landslides, debris flows and debris torrents, sometimes causing damage and death. The assessment of the rainfall thresholds for the initiation of shallow landslides is very important in order to improve forecasting and to arrange efficient alarm systems. With the aim of defining the critical rainfall thresholds for the Middle Serchio River Valley, a detailed analysis of the main rainstorm events was carried out. The hourly rainfall recorded by three rain gauges in the 1935–2010 interval was analysed and compared with the occurrence of shallow landslides. The rainfall thresholds were defined in terms of mean intensity I, rainfall duration D, and normalized using the mean annual precipitation. Some attempts were also carried out to analyze the role of rainfall prior to the damaging events. Finally, the rainfall threshold curves obtained for the study area were compared with the local, regional and global curves proposed by various authors. The results of this analysis suggest that in the study area landslide activity initiation requires a higher amount of rainfall and greater intensity than elsewhere

The Role of Emotional Regulation in the LGBTQIA+ Community: a Narrative Review

openil ruolo della regolazione emotiva e comunità lgbtqia+the role of emotion regulation and the LGBTQIA+ communit

Oral anticoagulant therapy in atrial fibrillation older patients with previous bleeding

Oral anticoagulant therapy (OAT) with direct oral anticoagulant (DOACs) is the established treatment to reduce thromboembolic risk in patients with atrial fibrillation (AF). Bleeding risk scores are useful to identify and correct factors associated with bleeding risk in AF patients on OAT. However, the clinical scenario is more complex in patients with previous bleeding event, and the decision about whether and when starting or re-starting OAT in these patients remains a contentious issue. Major bleeding is associated with a subsequent increase in both short- and long-term mortality, and even minimal bleeding may have prognostic importance because it frequently leads to disruption of antithrombotic therapy. There is an unmet need for guidance on how to manage antithrombotic therapy after bleeding has occurred. While waiting for observational and randomized data to accrue, this paper offers a perspective on managing antithrombotic therapy after bleeding in older patients with AF