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Journal of Thermal Science 2015年第6期24卷 526-534页

作者： Michele Marconcini Roberto Pacciani andrea Arnone University of Florence Department of Industrial Engineering Via Santa Marta

The aerodynamic performance of a gas turbine nozzle vane cascade was investigated over a range of Mach and Reynolds *** work is part of a vast research project aimed at the analysis of fluid dynamics and heat transfer phenomena in cooled *** this paper computed results on the"solid vane"(without cooling devices)are presented and discussed in comparison with experimental *** measurements were provided by the University of Bergamo where the experimental campaign was carried out by means of a subsonic wind *** impact of boundary layer transition is investigated by using a novel laminar kinetic energy transport model and the widely used Langtry-Menterγ-Reθ,t *** comparison between calculations and measurements is presented in terms of blade loading distributions,total pressure loss coefficient contours downstream of the cascade,and velocity/turbulence-intensity profiles within the boundary layer at selected blade surface locations at *** will be shown how transitional calculations compare favorably with experiments.

关键词： Gas turbine CFD validation transition model secondary flows

Novel Galectin-3 interactions involved in oligodendroglial differentiation make inroads into therapeutic strategies for demyelinating diseases

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Neural Regeneration Research 2021年第2期16卷 289-290页

作者： Laura andrea Pasquini Department of Biological Chemistry School of Pharmacy and BiochemistryInstitute of Biological Chemistry and Physicochemistry(IQUIFIB)University of Buenos Aires and National Research Council(CONICET)Buenos AiresArgentina

Galectins(Gals)constitute a 15-member class ofβ-galactoside-binding lectins which recognize *** lacking specific receptors,Gals form multivalent complexes with cell surface glycoconjugates containing suitable oligosaccharides and thus trigger intracellular signals to regulate cell survival and *** are classified into three groups on the basis of their structural architecture:proto,chimera and tandem types。

关键词： spite complexes strategies

l_(1)-based calibration of POD-Galerkin models of two-dimensional unsteady flows

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Chinese Journal of Aeronautics 2021年第1期34卷 226-236页

作者： Riccardo RUBINI Davide LASAGNA andrea DA RONCH Faculty of Engineering and Physical Sciences University of SouthamptonSouthampton SO171BJUnited Kingdom

This paper discusses a physics-informed methodology aimed at reconstructing efficiently the fluid state of a ***,the generation of an accurate reduced order model of twodimensional unsteady flows from data leverages on sparsity-promoting statistical learning *** cornerstone of the approach is l_(1) regularised regression,resulting in sparselyconnected models where only the important quadratic interactions between modes are *** original dynamical behaviour is reproduced at low computational costs,as few quadratic interactions need to be *** approach has two key ***,interactions are selected systematically as a solution of a convex optimisation problem and no a priori assumptions on the physics of the flow are ***,the presence of a regularisation term improves the predictive performance of the original model,generally affected by noise and poor data *** cases are for two-dimensional lid-driven cavity flows,at three values of the Reynolds number for which the motion is chaotic and energy interactions are scattered across the *** is found that:(A)the sparsification generates models maintaining the original accuracy level but with a lower number of active coefficients;this becomes more pronounced for increasing Reynolds numbers suggesting that extension of these techniques to real-life flow configurations is possible;(B)sparse models maintain a good temporal stability for *** methodology is ready for more complex applications without modifications of the underlying theory,and the integration into a cyberphysical model is feasible.

关键词： Computational methods Dynamical systems Lid-driven cavity L_(1)-based regression Reduced order models Sparsification Stabilization of ROMs

New oral agents for erectile dysfunction: what is changing in our practice?

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Asian Journal of Andrology 2001年第3期3卷 175-179页

作者： Antonio Aversa andrea Fabbri AFaR-CRCC Fatebenefratelli-Isola Tiberina Hospital and Endocrinology Unit Department of Internal Medicine University of Rome 'Tor Vergata' 00133 Rome ItalyEndocrinology Unit Department of Internal Medicine University of Rome 'Tor Vergata' 00133 Rome Italy

Erectile dysfunction (ED) is a highly prevalent disorder affecting an estimated 152 million men worldwide and isassociated with a variety of behavioral risk factors, such as cigarette smoking and excessive alcohol consumption, aswell as numerous age - related medical conditions, notably type-2 diabetes mellitus and cardiovascular disease. A ratio-nal step - wise approach which includes comprehensive medical and sexual history, a focused physical examination andessential laboratory tests such as fasting glucose, lipid profile and testosterone assay is to be preferred. Current diagnos-tic work - up does not recommend any of the specialized tests which were previously considered mandatory-i. e. penilepharmacotesting, Duplex ultrasound and nocturnal penile tumescence. Hormonal replacement therapy is appropriate onlyin the hypogonadal male with ED. Prior to direct intervention, the physician should consider altering modifiable riskfactors or causes, although frequently insufficient to reverse ED completely. When indicated, oral therapy with newmolecules (phosphodiesterase inhibitors or apomorphine) is the first - line treatment for the majority of patients becauseof potential benefits and lack of invasiveness. (Asian J Androl 2001 Sep; 3: 175-179 )

关键词： erectile dysfunction oral medicine therapy phosphodiesterase inhibitors apomorphine nitric oxide

A simplified pneumatic model for air brake of passenger trains

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Railway Engineering Science 2023年第2期31卷 145-152页

作者： Luciano Cantone andrea Ottati Department of Enterprise Engineering“Mario Lucertini” University of Rome Tor VergataRomeItaly Technical Direction TrenitaliaFSI GroupFlorenceItaly

Braking system performance is relevant for both railway safety and network optimization. Most trains employ air brake systems;air brake systems of freight trains mostly cannot achieve a synchronous application of brake forces, which is usually customary for passenger trains. The paper generalizes a previous air brake pneumatic model to passenger trains and describes the needed modifications. Among them, the way the pressure reduces in the brake pipe is generalized. Moreover, this paper reports an analytical bi-dimensional function for calculating the nozzle diameter equivalent to the electro-pneumatic(EP) or the electronically controlled pneumatic(ECP)brake valve as a function of the wagon length and the time to vent the brake pipe locally. The numerical results of the new model are compared against several experimental tests of high-speed passenger trains of Trenitalia, namely ETR500 and ETR1000. The model is suitable to be integrated into the UIC software TrainDy, aiming to extend its computational field to passenger trains and to simulate the safety of trains during a recovery.

关键词： EP or ECP modeling Model validation TrainDy Train brake Air brake

Dynamic expression of ATF3 as a novel tool to study activation and migration of endogenous spinal stem cells and their role in neural repair

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Neural Regeneration Research 2015年第5期10卷 713-714页

作者： Miranda Mladinic andrea Nistri Department of Biotechnology University of Rijeka Neuroscience Department International School for Advanced Studies (SISSA)34136 TriesteItaly (Nistri 1)

One of the major problems of modern neurobiology is how to replace dead or damaged neurons in the human brain or spinal cord after injury or as a consequence of neurodegenerative dis- eases. In fact, because adult mammalian neurons are post-mi- totic cells that cannot divide to replace dead cells, loss due to lesion or disease is permanent. Furthermore, surviving neurons have modest capacity to regenerate their damaged axons and re-establish functional connections. Thus, a gradual neurode- generative scenario with certain similarities in stroke, brain or spinal cord injuries and neurological diseases like Alzheimer＇s disease is produced. These conditions represent the major disease burden of the modern world in terms of mortality, dis- ability, productivity loss and health-care costs （World Health Organization, 2008）. While much effort has been directed to understand the molecular and cellular mechanisms involved in the pathology of these diseases to set new effective treatments, many neuroprotective and regenerative approaches, although showing positive results in preclinical studies, have so far failed to provide strong benefit to patients.

关键词： stem cell ATF

A Low Mach Number IMEX Flux Splitting for the Level Set Ghost Fluid Method

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Communications on Applied Mathematics and Computation 2023年第2期5卷 722-750页

作者： Jonas Zeifang andrea Beck Faculty of Sciences Hasselt UniversityAgoralaan Gebouw DBE-3590 DiepenbeekBelgium Institute of Aerodynamics and Gas Dynamics University of StuttgartPfaffenwaldring 2170569 StuttgartGermany Laboratory of Fluid Dynamics and Technical Flows Otto von Guericke University MagdeburgUniversitatsplatz 239106 MagdeburgGermany

Considering droplet phenomena at low Mach numbers,large differences in the magnitude of the occurring characteristic waves are *** acoustic phenomena often play a minor role in such applications,classical explicit schemes which resolve these waves suffer from a very restrictive timestep *** this work,a novel scheme based on a specific level set ghost fluid method and an implicit-explicit(IMEX)flux splitting is proposed to overcome this timestep restriction.A fully implicit narrow band around the sharp phase interface is combined with a splitting of the convective and acoustic phenomena away from the *** this part of the domain,the IMEX Runge-Kutta time discretization and the high order discontinuous Galerkin spectral element method are applied to achieve high accuracies in the bulk *** is shown that for low Mach numbers a significant gain in computational time can be achieved compared to a fully explicit ***-tions to typical droplet dynamic phenomena validate the proposed method and illustrate its capabilities.

关键词： IMEX flux splitting Level set method Ghost fluid method Low Mach number flows

A map-matching algorithm dealing with sparse cellular fingerprint observations

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Geo-Spatial Information Science 2019年第2期22卷 89-106,I0002页

作者： andrea Dalla Torre Paolo Gallo Donatella Gubiani Chris Marshall Angelo Montanari Federico Pittino andrea Viel Cellular Product Center u-blox Italia SpATriesteItaly Department of Mathematics Computer Science and PhysicsUniversity of UdineUdineItaly Center for Information Technologies and Applied Mathematics University of Nova GoricaNova GoricaSlovenia Cellular Technology u-blox UK LtdReigateUK

The widespread availability of mobile communication makes mobile devices a resource for the collection of data about mobile infrastructures and user *** these contexts,the problem of reconstructing the most likely trajectory of a device on the road network on the basis of the sequence of observed locations(map-matching problem)turns out to be particularly *** contributions have demonstrated that the reconstruction of the trajectory of a device with good accuracy is technically feasible even when only a sparse set of GNSS positions is *** this paper,we face the problem of coping with sparse sequences of cellular *** to GNSS positions,cellular fingerprints provide coarser spatial information,but they work even when a device is missing GNSS positions or is operating in an energy saving *** devise a new map-matching algorithm,that exploits the well-known Hidden Markov Model and Random Forests to successfully deal with noisy and sparse cellular *** performance of the proposed solution has been tested over a medium-sized Italian city urban environment by varying both the sampling of the observations and the density of the fingerprint map as well as by including some GPS positions into the sequence of fingerprint observations.

关键词： Map-matching algorithm trajectory cellular fingerprint Hidden Markov Model

Gravitational waves from dark first order phase transitions and dark photons

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Chinese Physics C 2018年第2期42卷 81-85页

作者： andrea Addazi Antonino Marcianò Department of Physics & Center for Field Theory and Particle Physics Fudan University

Cold Dark Matter particles may interact with ordinary particles through a dark photon, which acquires a mass thanks to a spontaneous symmetry breaking mechanism. We discuss a dark photon model in which the scalar singlet associated to the spontaneous symmetry breaking has an effective potential that induces a first order phase transition in the early Universe. Such a scenario provides a rich phenomenology for electron-positron colliders and gravitational waves interferometers, and may be tested in several different channels. The hidden first order phase transition implies the emission of gravitational waves signals, which may constrain the dark photon＇s space of parameters. Compared limits from electron-positron colliders, astrophysics, cosmology and future gravitational waves interferometers such as eLISA, U-DECIGO and BBO are discussed. This highly motivates a cross-checking strategy of data arising from experiments dedicated to gravitational waves, meson factories, the International Linear Collider（ILC）, the Circular Electron Positron Collider（CEPC） and other underground direct detection experiments of cold dark matter candidates.

关键词： dark matter gravitational waves colliders

Spatio-temporal coupled mode theory for nonlocal metasurfaces

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Light(Science & Applications) 2024年第2期13卷 267-282页

作者： Adam Overvig Sander A.Mann andrea Alù Photonics Initiative Advanced Science Research CenterCity University of New YorkNew YorkNY10031USA Physics Program Graduate Center of the City University of New YorkNew YorkNY10016USA

Diffractive nonlocal metasurfaces have recently opened a broad range of exciting developments in nanophotonics research and applications,leveraging spatially extended—yet locally patterned—resonant modes to control light with new degrees of *** conventional grating responses are elegantly captured by temporal coupled mode theory,current approaches are not well equipped to capture the arbitrary spatial response observed in the nascent field of nonlocal ***,we introduce spatio-temporal coupled mode theory(STCMT),capable of elegantly capturing the key features of the resonant response of wavefront-shaping nonlocal *** framework can quantitatively guide nonlocal metasurface design while maintaining compatibility with local metasurface frameworks,making it a powerful tool to rationally design and optimize a broad class of ultrathin optical *** validate this STCMT framework against full-wave simulations of various nonlocal metasurfaces,demonstrating that this tool offers a powerful semi-analytical framework to understand and model the physics and functionality of these devices,without the need for computationally intense full-wave *** also discuss how this model may shed physical insights into nonlocal phenomena in photonics and the functionality of the resulting *** a relevant example,we showcase STCMT’s flexibility by applying it to study and rapidly prototype nonlocal metasurfaces that spatially shape thermal emission.

关键词： theory resonant spatially