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Journal of Geriatric Cardiology 2015年第5期12卷 580-583页

作者： davide Stolfo Pasquale Gianfagna Enrico Fabris davide Zanuttini Gianfranco Sinagra Alessandro Proclemer Gaetano Nucifora Department of Cardiology 'Ospedali Riuniti' and University of Trieste Trieste Italy Cardiothoracic Department University Hospital 'Santa Maria della Misericordia ' Udine Italy

A 76-year-old Caucasian woman was admitted to the emergency room and referred for cardiac evaluation for dyspnea and abrupt onset of cough three weeks ago. She had a history of well-controlled arterial hypertension and was on adequate oral anticoagulant therapy for permanent atrial fibrillation. Previous thoracic injuries, connective tis- sue disorders or recent infections were excluded. No chest pain or syncope was reported. mmHg in both arms, heart rate Blood pressure was 150/50 was 90 beats/min.

关键词： Aortic valve rupture Multislice computed tomography Pseudoaneurysm of the ascending aorta Transesophageal echocardiography

Non-pharmacological interventions for Parkinson’s disease mild cognitive impairment: future directions for research

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Neural Regeneration Research 2020年第9期15卷 1650-1651页

作者： davide Maria Cammisuli Roberto Ceravolo Ubaldo Bonuccelli Neurology Clinic Department of Clinical and Experimental MedicineUniversity of PisaPisaItaly Clinical Psychology Psychophysiology and Clinical Neuropsychology LaboratoryDepartment of Medicine and SurgeryUniversity of ParmaParmaItaly

Parkinson’sdisease-mildcognitiveimpairment(PD-MCI)currently represents a valid diagnostic clinical entity with potential interest for therapeutic *** is present in approximately 25–30%of non-demented patients with PD(Weintraub et al.,2018).Several risk factors are associated with Parkinson’s disease dementia(PDD)occurrence,such asoldageatonset,longdiseaseduration,motorimpairment and MCI(Nicoletti et al.,2019).

关键词： impairment al. clinical

Tidal drag and westward drift of the lithosphere

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Geoscience Frontiers 2023年第6期14卷 102-116页

作者： Vincenzo Nesi Oscar Bruno davide Zaccagnino Corrado Mascia Carlo Doglioni Dipartimento di Matematica Guido Castelnuovo Piazzale Aldo Moro5Roma 00185Italy Istituto Nazionale di Geofisica e Vulcanologia Via di Vigna Murata605Roma 00143Italy Computing and Mathematical Sciences Department Caltech1200 E.California Blvd.MC 305-16Pasadena 91125CAUSA Dipartimento di Scienze della Terra Piazzale Aldo Moro5Roma 00185Italy

Tidal forces are generally neglected in the discussion about the mechanisms driving plate tectonics despite a worldwide geodynamic asymmetry also observed at subduction and rift *** tidal drag could theoretically explain the westerly shift of the lithosphere relative to the underlying ***,viscosity in the asthenosphere is apparently too high to allow mechanical decoupling produced by tidal ***,we propose a model for global scale geodynamics accompanied by numerical simulations of the tidal interaction of the Earth with the Moon and the *** provide for the first time a theoretical proof that the tidal drag can produce a westerly motion of the lithosphere,also compatible with the slowing of the Earth’s rotational *** results suggest a westerly rotation of the lithosphere with a lower bound ofω≈(0.1-0.2)°/Myr in the presence of a basal effective shear viscosityη≈10^(16)Pa-s,but it may rise toω>1°/Myr with a viscosity ofη≈≤3×10^(14)Pa-s within the Low-Velocity Zone(LVZ)atop the *** faster velocity would be more compatible with the mainstream of plate motion and the global asymmetry at plate *** on these computations,we suggest that the super-adiabatic asthenosphere,being vigorously convecting,may further reduce the viscous coupling within the LVZ Therefore,the combination of solid Earth tides,ultra-low viscosity LVZ and asthenospheric polarized small-scale convection may mechanically satisfy the large-scale decoupling of the lithosphere relative to the underlying *** plate motions are explained because of lateral viscosity heterogeneities at the base of the lithosphere,which determine variable lithosphere-asthenosphere decoupling and plate interactions,hence plate tectonics.

关键词： Tidal drag Plate motions Polarized plate tectonics Lithosphere-asthenosphere interaction

Landslide on glaciers: an example from Western Alps(Cogne-Italy)

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Journal of Mountain Science 2020年第5期17卷 1161-1171页

作者： FRASCA Marco VACHA Damiano CHICCO Jessica TROILO Fabrizio BERTOLO davide Fondazione Montagna Sicura Localita Villard de la Palud 111013 CourmayeurAostaItaly Universita degli Studi di Torino Department of Earth SciencesVia Valperga Caluso 3510125 TorinoItaly Regione Autonoma Valle d'Aosta-Assessorato alle opere pubbliche territorio ed edilizia residenziale pubblicaLocalita Ameriquen.3311020 QuartAostaItaly

In the warm summer of 2017,a landslide failed from the south-east side of the Col des Clochettes on the top of the underlying Trajo *** study area is at an elevation of about 3500 m *** the Gran Paradiso Massif and can be hardly reached by walking from Cogne(Aosta Valley,NW Italy).Studies conducted by field surveys,photogrammetry(structure from motion)and satellite images analysis,integrated with the evaluation of data from meteorological stations have been used to reconstruct the phenomenon and infer its *** site is very complex to be studied especially due to logistic problems,therefore,measurements and observations that are common practice in other landslides are very difficult to apply ***,many of the results achieved are not adequately supported by field ***,the following factors could have affected the stability of the slope:i)the tectonic structure of the area,which is reflected on the morphology and on the geomechanics characteristics of the rock masses;ii)the meteorological conditions during 3 months before the main failure,resulting in an extremely high temperature compared to historical ***,the analysis of multitemporal satellite images allowed to recognize that it was not a single landslide but that the phenomenon is articulated over time in at least five failures in about 2 ***,several predisposing factors may have been playing an important role in causing the instability:the degradation of permafrost(probably affecting rock mass due to the circulation of warm air and water in the discontinuity systems),the alternance of the freeze-thaw cycles and the availability of a considerable amount of water from rainfalls and nival fusion infiltrating deeply in the rock *** common causes such as rains and earthquakes have been excluded.

关键词： Landslide Glacier Remote sensing Climate changes Western Italian Alps

Experimental and Numerical Analysis of Cavity/Mean-Flow Interaction in Low Pressure Axial Flow Turbines

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Journal of Thermal Science 2021年第6期30卷 2178-2185页

作者： BARSI Dario COSTA Carlo LENGANI davide SIMONI Daniele VENTURINO Giulio ZUNINO Pietro DIME-Universita di Genova Via Montallegro 11-16145 Genova

The increasing performance of modern aeroengines led the research towards the optimization of machine components not deeply analyzed in the *** this context,the mechanisms driving the interaction process between the secondary flows evolving at the hub of low-pressure turbines with the rotor-stator cavity systems have been poorly investigated in the *** this work,an experimental and numerical analysis of the interaction between the endwall near wall flow and the leakage flow of a real cavity system is *** experimental results were carried out in the annular low-pressure axial flow turbine of the University of *** blade loading and pressure distributions into the cavity,as well as the measured total pressure loss coefficient,have been used for a proper validation of CFD *** steady and unsteady calculations were carried out through the commercial solver ***,several numerical approaches have been tested into this work:RANS,Non Linear Harmonic(NLH),and *** most promising CFD techniques have been firstly identified by comparison with experimental results and then systematically employed to extend the analysis of secondary flow-cavity flow interaction to positions and quantities not available from the *** characterizing the mean flow-cavity flow interaction process will be shown to cover a great amount of the overall stage losses and should be properly accounted for the design of future optimized cavity configurations.

关键词： axial flow turbine cavity mean-flow interaction experimental analysis CFD

Velocity profiles description and shape factors inclusion in a hyperbolic,one-dimensional,transient two-fluid model for stratified and slug flow simulations in pipes

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Petroleum 2019年第2期5卷 191-198页

作者： Arianna Bonzanini davide Picchi Marco Ferrari Pietro Poesio Dipartimento di Ingegneria Meccanica ed Industriale Universita degli Studi di BresciaVia Branze3825123BresciaItaly Energy Resources Engineering Stanford UniversityStanford94305CAUnited States Department of Mathematics Politecnico di Milanop.zza Leonardo da Vinci3220133MilanItaly

In a previous work it has been shown that a one-dimensional,hyperbolic,transient five equations twofluid model is able to numerically describe stratified,wavy,and slug flow in horizontal and nearhorizontal *** statistical characteristics can be numerically predicted with results in good agreement with experimental data and well-known empirical *** this model some approximated and simplified assumptions are adopted to describe shear stresses at wall and at phase *** this paper,we focus on the possibility to account for the cross sectional flow by inserting shape factors into the momentum balance equations of the aforementioned *** profiles are obtained by a pre-integrated model and they are computed at each time step and at each computational *** that the velocity profiles are known,the obtained shape factors are inserted in the numerical *** this way it is possible to recover part of the information lost due to the one-dimensional flow *** profiles computed in stratified conditions are compared against experimental profiles measured by PIV technique;a method to compute the velocity profile during slug initiation and growth has been developed and the computed velocity distribution in the liquid phase was compared against the one-seventh power law.

关键词： Multi-phase pipeline transport Oil&gas Hyperbolic two-fluid model Velocity profiles Shape factors

Characterizing the influence of stress-induced microcracks on the laboratory strength and fracture development in brittle rocks using a finite-discrete element method-micro discrete fracture network FDEM-μDFN approach

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Journal of Rock Mechanics and Geotechnical Engineering 2015年第6期7卷 609-625页

作者： Pooya Hamdi Doug Stead davide Elmo Simon Fraser University 8888 University Drive NBK Institute of Mining Engineering University of British Columbia

Heterogeneity is an inherent component of rock and may be present in different forms including mineralheterogeneity, geometrical heterogeneity, weak grain boundaries and micro-defects. Microcracks areusually observed in crystalline rocks in two forms： natural and stress-induced; the amount of stressinducedmicrocracking increases with depth and in-situ stress. Laboratory results indicate that thephysical properties of rocks such as strength, deformability, P-wave velocity and permeability areinfluenced by increase in microcrack intensity. In this study, the finite-discrete element method （FDEM）is used to model microcrack heterogeneity by introducing into a model sample sets of microcracks usingthe proposed micro discrete fracture network （mDFN） approach. The characteristics of the microcracksrequired to create mDFN models are obtained through image analyses of thin sections of Lac du Bonnetgranite adopted from published literature. A suite of two-dimensional laboratory tests including uniaxial,triaxial compression and Brazilian tests is simulated and the results are compared with laboratory *** FDEM-mDFN models indicate that micro-heterogeneity has a profound influence on both the mechanicalbehavior and resultant fracture pattern. An increase in the microcrack intensity leads to areduction in the strength of the sample and changes the character of the rock strength envelope. Spallingand axial splitting dominate the failure mode at low confinement while shear failure is the dominantfailure mode at high confinement. Numerical results from simulated compression tests show thatmicrocracking reduces the cohesive component of strength alone, and the frictional strength componentremains unaffected. Results from simulated Brazilian tests show that the tensile strength is influenced bythe presence of microcracks, with a reduction in tensile strength as microcrack intensity increases. Theimportance of microcrack heterogeneity in reproducing a bi-linear or S-shape failure

关键词： Finite-discrete element method(FDEM) Micro discrete fracture network(μDFN) Brittle fracture

Pediatric liver transplantation

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World Journal of Gastroenterology 2009年第6期15卷 648-674页

作者： Marco Spada Silvia Riva Giuseppe Maggiore davide Cintorino Bruno Gridelli Istituto Mediterraneo peri Trapiantie Terapie ad alta specializzazione-IsMeTT University of Pittsburgh Medical Center90127 PalermoItaly Department of Reproductive Medicine and Child Development University of Pisa56100 PisaItaly

In previous decades,pediatric liver transplantation has become a state-of-the-art operation with excellent success and limited *** and patient survival have continued to improve as a result of improvements in medical,surgical and anesthetic management,organ availability,immunosuppression,and identification and treatment of postoperative *** utilization of split-liver grafts and living-related donors has provided more organs for pediatric *** immunosuppression regimens,including induction therapy,have had a significant impact on graft and patient *** developments of pediatric liver transplantation will deal with long-term followup,with prevention of immunosuppression-related complications and promotion of as normal growth as *** review describes the state-of-the-art in pediatric liver transplantation.

关键词： Pediatric liver transplantation Indications Surgical techniques Complications

Exergy Analysis of Organic Rankine Cycles with Zeotropic Working Fluids

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Fluid Dynamics & Materials Processing 2023年第3期19卷 593-601页

作者： Antonio Mariani davide Laiso Biagio Morrone Andrea Unich Department of Engineering DI Universitàdella Campania“Luigi Vanvitelli”Aversa(CE)Caserta81031Italy

Waste heat recovery is one of the possible solutions to improve the efficiency of internal combustion *** of wasting the exhaust stream of an energy conversion system into the environment,its residual energy content can be usefully recovered,for example in Organic Rankine Cycles(ORC).This technology has been largely consolidated in stationary power plants but not yet for mobile applications,such as road transport,due to the limitations in the layout and to the constraints on the size and weight of the ORC *** ORC system installed on the exhaust line of a bus powered by a natural gas spark ignition engine has been *** thermal power available at engine exhaust has been evaluated by measuring gas temperature and mass flow rate during real driving *** waste thermal power has been considered as heat input for the ORC plant simulation.A detailed heat exchanger model has been developed because it is a crucial component for the ORC *** exergy analysis of the ORC was performed comparing different working fluids:R601,R1233zd(E)and two zeotropic blends of the two organic pure *** model allowed the evaluation of the ORC produced energy over the driving cycle and the potential benefit on the engine efficiency.

关键词： Organic Rankine Cycle zeotropic mixtures exergy analysis waste heat recovery engine efficiency internal combustion engine

Alternative stable states in mountain forest ecosystems： the case of European larch(Larix decidua) forests in the western Alps

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Journal of Mountain Science 2017年第5期14卷 811-822页

作者： Jose V.MORIS Giorgio VACCHIANO davide ASCOLI Renzo MOTTA University of Turin DISAFALargo Paolo Braccini 210095 Grugliasco(TO)Italy

European larch(Larix decidua) forests of the western Alps form extensivecultural landscapes whose resilience to global changes is currently unknown. Resilience describes the capacity of ecological systems to maintain the same state, i.e., the same function, processes, structure, and composition despite disturbances, environmental changes and internal fluctuations. Our aim is to explore the resilience of larch forests to changes in climate and land use in the western Italian *** do so, we examined whether larch forests can be described as an alternative stable state in mountain forest ecosystems. We used tree basal area data obtained from field forest inventories in combination with topography, forest structure, land use, and climate information. We applied three different probabilistic methods: frequency distributions, logistic regressions, and potential analyses to infer the resilience of larch forests relative to that of other forest *** found patters indicative of alternative stable states: bimodality in the frequency distribution of the percent of larch basal area, and the presence of an unstable state, i.e., mixed larch forests, in the potential analyses. We also found:(1) high frequency ofpurelarchforestsathighelevation,(2)the probability of pure larch forests increased mostly with elevation, and(3) pure larch forests were a stable state in the upper montane and subalpine *** study shows that the resilience of larch forests may increase with elevation, most likely due to the altitudinal effect on climate. Under the same climate conditions, land use seems to be the main factor governing the dominance of larch forests. In fact, subalpine larch forests may be more resilient, and natural succession after land abandonment, e.g., towards Pinuscembra forests, seems slower than in montane larch forests. In contrast, in the upper montane belt only intense land use regimes characterized by open canopies and forest grazing may maintain larch *** con

关键词： Resilience Ecosystem bistability Elevation Land use Natural succession Pinuscembra European larch