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UV and soft x-ray emission from gaseous and solid targets employing SiC detectors

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Plasma Science and Technology 2021年第5期23卷 147-154页

作者： Alfio TORRISI Przemysław WACHULAK lorenzo TORRISI CEDAD-Dept.of Mathematics and Physics‘E.De Giorgi’ University of SalentoLecce 73100Italy Institute of Optoelectronics Military University of TechnologyWarsaw 00-908Poland Dept.of Mathematical and Computer Sciences Physical Sciences and Earth Sciences(MIFT)-University of MessinaMessina 98166Italy

A ns Nd:YAG pulsed laser has been employed to produce plasma from the interaction with a dense target,generating continuum and UV and soft x-ray emission depending on the laser parameters and target *** laser hits solid and gaseous targets producing plasma in high vacuum,which was investigated by employing a silicon carbide *** two different interaction mechanisms were studied,as well as their dependence on the atomic *** photon emission from laser-generated plasma produced by solid targets,such as boron nitride(BN)and other elements(Al,Cu,Sn and Ta)and compounds such as polyethylene,has been compared with that coming from plasma produced by irradiating different gas-puff targets based on N_(2)and other gases(Ar,Xe,Kr,SF_(6)).The experimental results demonstrated that the yields are comparable and,in both cases,increase proportionally to the target atomic *** obtained results,focusing the attention on the advantages and drawbacks of the employed targets,are presented and discussed.

关键词： laser-matter interaction plasma diagnostics SiC detectors

High Order Semi-implicit Multistep Methods for Time-Dependent Partial Differential Equations

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Communications on Applied Mathematics and Computation 2021年第4期3卷 701-718页

作者： Giacomo Albi lorenzo Pareschi Computer Science Department University of VeronaVerona 37134Italy Mathematics and Computer Science Department University of FerraraFerrara 44121Italy

We consider the construction of semi-implicit linear multistep methods that can be applied to time-dependent PDEs where the separation of scales in additive form,typically used in implicit-explicit(IMEX)methods,is not *** shown in Boscarino et al.(***.68:975-1001,2016)for Runge-Kutta methods,these semi-implicit techniques give a great flexibility,and allow,in many cases,the construction of simple linearly implicit schemes with no need of iterative *** this work,we develop a general setting for the construction of high order semi-implicit linear multistep methods and analyze their stability properties for a prototype lineal'advection-diffusion equation and in the setting of strong stability preserving(SSP)*** findings are demonstrated on several examples,including nonlinear reaction-diffusion and convection-diffusion problems.

关键词： Semi-implicit methods Implicit-explicit methods Multistep methods Strong stability preserving High order accuracy

Regeneration of adhesive tail pad scales in the New Zealand gecko (Hoplodactylus maculatus) (Reptilia, Squamata; Lacertilia) can serve as an experimental model to analyze setal formation in lizards generally

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Zoological Research 2017年第4期38卷 191-197页

作者： lorenzo Alibardi Benno Meyer-Rochow Comparative Histolab and Department of Bigea Dipartimento di Biologia University of Bologna Bologna 40126 Italy Research Institute of Luminous Organisms Tokyo 100-1623 Japan Department of Genetics and Physiology Oulu University Oulu FIN 90140 Finland

During the regeneration of the tail in the arboreal New Zealand gecko （Hoplodactylus maculatus） a new set of tail scales, modified into pads bearing setae 5-20 μm long, is also regenerated. Stages of the formation of these specialized scales from epidermal pegs that invaginate the dermis of the regenerating tail are described on the basis of light and electron microscopic images. Within the pegs a differentiating clear layer interfaces with the spinulae and setae of the Oberh^utchen according to a process similar to that described for the digital pads. A layer of clear cytoplasm surrounds the growing tiny setae and eventually comities around them and their spatular ends, later leaving the new setae free- standing on the epidermal surface. The fresh adhesive pads help the gecko to maintain the prehensile function of its regenerated tail as together with the axial skeleton （made of a cylinder of elastic cartilage） the pads allow the regenerated tail to curl around twigs and small branches just like the original tail. The regeneration of caudal adhesive pads represents an ideal system to study the cellular processes that determine setal formation under normal or experimental manipulation as the progressive phases of the formation of the setae can be sequentially analyzed.

关键词： Gecko lizard Regeneration Epidermis Tail pad scales Adhesion Prehensile function Ultrastructure

Eccentric Computational Embodiments: Cognitive Domestication of External Entities

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学术界 2020年第1期 185-197页

作者： lorenzo Magnani Department of Humanities Philosophy Section and Computational Philosophy Laboratory University of Pavia

The emphasis on the simplification of cognitive and motor tasks by recent results of morphological computation has rendered possible the construction of appropriate“mimetic bodies”able to render accompanied computations simpler,according to a general appeal to the“simplexity”of animal embodied cognition.A new activity of what we can call“distributed computation”holds the promise of originating a new generation of robots with better adaptability and restricted number of required control *** framework of distributed computation helps us see them in a more naturalized and prudent perspective,avoiding ontological or metaphysical *** these progresses,there are still problems regarding the epistemological limitations of computational modeling remain to be solved.

关键词： morphological computation physical computation mimeticbodies computational substrates pancomputationalism simplexity

MEAT AND MEAT PRODUCTS

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Journal of Integrative Agriculture 2013年第11期12卷 1916-1918页

作者： José M lorenzo Centro Tecnológico de la Carne de Galicia

In recent years, meat quality has assumed a greater consumer significance and public attention. There is growing awareness of the link between diet and health and this is reflected in the demand for more information a... 详细信息

关键词： MEAT AND MEAT PRODUCTS

How do stream processes affect hazard exposure on alluvial fans? Insights from an experimental study

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Journal of Mountain Science 2020年第4期17卷 753-772页

作者： Bruno MAZZORANA Elisa GHIANDONI lorenzo PICCO Universidad Austral de Chile Faculty of SciencesInstituto de Ciencias de la Tierra5090000 ValdiviaChile Universidad Austral de Chile RINA–Natural and Anthropogenic Risks Research Center5090000 ValdiviaChile Universidad Austral de Chile Laboratory of HydromorphologyFaculty of Forest Sciences and Natural Resources5090000 ValdiviaChile University of Padova Department of LandEnvironmentAgriculture and Forestry35020 LegnaroItaly

Alluvial fans are among the most privileged settlement areas in many mountain regions. These landforms are particularly dynamic being episodically affected by distributary processes generated by extreme flood events. Addressing risk assessment entails determining hazard exposure and unravelling how it might be related to process loading and to process dynamics once the flow becomes unconfined on the surface of alluvial fans. By following a ‘similarity of process concept’, rather than by attempting to scale a real-world prototype, we performed a set of 72 experimental runs on an alluvial fan model. Thereby, we considered two model layouts, one without a guiding channel and featuring a convex shape and the other one with a guiding channel, a bridge, and inclined but planar overland flow areas as to mirror an anthropic environment. Process magnitude and intensity parameters were systematically varied, and the associated biphasic distributary processes video recorded. For each experiment, the exposure was detected by mapping the exposed area in a GIS, thereby discerning between areas exposed to biphasic flows and the associated depositional phenomena or to the liquid flow phase only. Our results reveal that total event volume, sediment availability and stream power in the feeding channel, as well as depositional effects, avulsion, and channelization on the alluvial fan concur to determine the overall exposure. Stream process loading alone, even when rigorously defined in terms of its characterizing parameters, is not sufficient to exhaustively determine exposure. Hence, further developing reliable biphasic simulation models for hazard assessment on settled alluvial fans is pivotal.

关键词： Alluvial fan Hazard Exposure Flood risk Experimental model Process similarity

Whole Field Strain Measurement of High Strength Steel Under Plain Strain Condition

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Journal of Iron and Steel Research International 2011年第S1期18卷 320-324页

作者： SMITH lorenzo M Department of Mechanical Engineering Oakland UniversityRochester 48309MIUnited States

Sheet metal undergoes different strain conditions during different forming *** investigation of mechanical properties under these conditions is very important in the forming *** metal is particularly liable to failure under plain strain *** and investigate the necking strain under plane strain condition is a particularly important study for sheet formability *** this study,material behavior of DP780 high strength steel sheet under plain strain condition was *** plane strain tensile tests were carried out on the MTS testing machine with a special designed specimen.A digital image correlation system was employed to measure the full-field strain distribution during plain strain tensile *** strain evolution during deformation was obtained and *** capability of the specimen for plane strain test was validated from the strain *** necking strain and fracture strain of DP780 high strength steel sheet were determined from the strain field and strain history results.

关键词： plain strain test strain history fracture high strength steel digital image correlation

Interferometric method to estimate the eigenvalues of a non-Hermitian two-level optical system

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Photonics Research 2022年第4期10卷 1134-1145页

作者： STEFANO BIASI RICCARDO FRANCHI FILIPPO MIONE lorenzo PAVESI Nanoscience Laboratory Dipartimento di FisicaUniversita di Trento38123 TrentoItaly

Non-Hermitian physics has found a fertile ground in optics. Recently, the study of mode coalescence, i.e., exceptional points, has led to the discovery of intriguing and counterintuitive phenomena. Degeneracies are typically modeled through the coupled mode theory to determine the behavior of eigenstates and eigenvalues. However,the complex nature of the eigenvalues makes their characterization from the response spectrum difficult. Here,we demonstrate that a coherent interferometric excitation allows estimation of both the real and imaginary parts of the eigenvalues. We study the clockwise and counter-clockwise modes in optical microresonators both in the case of Hermitian and non-Hermitian intermodal coupling. We show the conditions by which a resonant doublet,due to the dissipative coupling of counter-propagating modes caused by surface roughness backscattering, merges to a single Lorentzian. This permits us to estimate the optimal quality factor of the microresonator in the absence of modal coupling caused by backscattering. Furthermore, we demonstrate that a taiji microresonator working at an exceptional point shows a degeneracy splitting only in one propagation direction and not in the other. This follows from the strongly non-Hermitian intermodal coupling caused by the inner S-shaped waveguide.

关键词： eigenvalues exceptional intuitive

On the role of hemodynamics in predicting rupture of the abdominal aortic aneurysm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2021年第12期22卷 957-978页

作者： Maria Antonietta BONIFORTI lorenzo DI BELLA Roberto MAGINI Department of Civil Buildingand Environmental EngineeringSapienza UniversityRome 00184Italy

Hemodynamics plays a crucial role in the growth of an abdominal aortic aneurysm(AAA)and its possible *** to the serious consequences that arise from the aneurysm rupture,the ability to predict its evolution and the need for surgery are of primary importance in the medical ***,the presence of intraluminal thrombus(ILT)strongly affects the evolution of the *** this study,we analyzed the influence of hemodynamics on the growth and possible rupture of *** investigations of pulsatile non-Newtonian blood flow were performed in six patient-specific AAAs reconstructed from diagnostic images,having different sizes and shapes,and with or without *** shear stress and vorticity distribution in the bulge and their evolution during the cardiac cycle were *** results indicate that blood flow dynamics acts synergistically with atherosclerotic degeneration in the development of the *** high surface complexity and tortuosity of the aneurysms significantly affect the blood motion,and the presence of inflection in the aneurysm centerline has a noticeable effect on the vortex *** between regions of slow recirculating flows,low values of time-averaged wall shear stress,high values of oscillatory shear index,and zones of ILT deposition were *** the absence of ILT,possible thrombus accumulation areas and consequent aneurysm growth were *** findings of this study highlight the importance of hemodynamics in assessing the vulnerability of the aortic wall and underline the crucial role of patient-specific investigations in predicting the rupture of individual aneurysms.

关键词： Hemodynamics Computational fluid dynamics Wall shear stress Vortex dynamics Abdominal aortic aneurysm(AAA) Patient-specific modelling