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Ultrafast spectroscopy of semiconductor saturable absorber mirror

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Chinese Optics Letters 2010年第7期8卷 676-679页

作者：张靓 Dominik Bauer farina knig Thomas Dekorsy 张喜和陈亚符 Department of Physics Changchun University of Science and Technology Department of Physics and Center of Applied Photonics University of Konstanz

Ultrafast spectroscopy of semiconductor saturable absorber mirror （SESAM） is measured using a femtosec- ond pump-probe experiment. This allows dynamic responses of SESAM in the cavity to be concluded by ultrafast spectroscopy. Change in reflection is measured as a function of pump-probe delay for different pump excitation fluences. Change of nonlinear reflection of SESAM is measured as a function of incident light energy density. When the excitation fluence increases, nonlinear change in ultrafast spectroscopy of SESAM becomes increasingly significant. When SESAM is pumped by an ultrahigh excitation fluence, the energy density of which is approximately 1400 μJ/cm2, two-photon absorption can be observed visibly in its ultrafast spectroscopy.

关键词： Dynamic response Light reflection Mirrors Probes Pumps Two photon processes

Role of copper in central nervous system physiology and pathology

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Neural Regeneration Research 2025年第4期20卷 1058-1068页

作者： Martina Locatelli Cinthia farina Institute of Experimental Neurology Division of NeuroscienceIstituto di Ricovero e Cura a Carattere Scientifico(IRCCS)San Raffaele Scientific InstituteMilanItaly Vita-Salute San Raffaele University MilanItaly

Copper is a transition metal and an essential element for the organism,as alterations in its homeostasis leading to metal accumulation or deficiency have pathological effects in several organs,including the central nervous *** copper dysregulations have been evidenced in two genetic disorders characterized by mutations in the copper-ATPases ATP7A and ATP7B,Menkes disease and Wilson’s disease,respectively,and also in multifactorial neurological disorders such as Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and multiple *** review summarizes current knowledge about the role of copper in central nervous system physiology and pathology,reports about unbalances in copper levels and/or distribution under disease,describes relevant animal models for human disorders where copper metabolism genes are dysregulated,and discusses relevant therapeutic approaches modulating copper ***,alterations in copper metabolism may contribute to the etiology of central nervous system disorders and represent relevant therapeutic targets to restore tissue homeostasis.

关键词： astrocytes central nervous system copper cuprizone multiple sclerosis myelin neurodegenerative disorders

The phenotypic convergence between microglia and peripheral macrophages during development and neuroinflammation paves the way for new therapeutic perspectives

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Neural Regeneration Research 2021年第4期16卷 635-637页

作者： Francesca Grassivaro Gianvito Martino Cinthia farina Institute of Experimental Neurology Division of NeuroscienceSan Raffaele Scientific InstituteMilanItaly Vita-Salute San Raffaele University MilanItaly

Microglia,the tissue resident macrophages of the brain,are increasingly recognized as key players for central nervous system development and *** are long-lived cells deriving from a transient wave of yolk-sac derived erythro-myeloid progenitors early in *** unique ontology has prompted the search for specific markers to be used for their selective investigation and *** first generation of genomewide expression studies has provided a bundle of transcripts(such as Olfml3,Fcrls,Tmem119,P2ry12,Gpr34,and Siglech)useful to distinguish microglia from peripheral ***,more recent reports have revealed that microglial phenotype is constantly shaped by the microenvironment in a time-,and context-dependent *** this article,we review data that provide additional pieces to this complex scenario and show the existence of unexpected phenotypic convergence between microglia and peripheral macrophages at certain developmental stages and under pathological *** observations suggest that the two cell types act synergically boosting their mutual activities depending on the *** novel information about the biology of microglia and peripheral macrophages sheds new light about their therapeutic potential for neuroinflammatory and neurodegenerative diseases.

关键词： cell reprogramming cell therapy macrophages microglia neuroinflammation plasticity

A mathematical model for the evolution of solute concentrations in a hemodialysis filter

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International Journal of Biomathematics 2018年第1期11卷 337-348页

作者： A. Fasano G. Guarnieri A. farina Dipartimento di Matematica e Informatica "U. Dini" Universita degli Studi di Firenze Firenze Italy

We consider the process of hemodialysis performed by means of a hollow fiber dialyzer with a special focus on the dynamics of the light solutes （including metabolic waste products） through the porous fibers membrane. The model we illustrate here completes the one formulated in a previous paper in which solutes concentrations in the dialyzate were neglected. Exploiting the large difference between the characteristic time of the processes in the machine and the relaxation time to equilibrium in the body, we confine our study to the case of constant input data in order to emphasize the role of the solute transport mechanisms. Numerical solutions show that diffusion is dominant at the early stage of filtration.

关键词： Hemodialysis solute concentration upscaling.

Detection with High Resolution Radar: Advanced Topics & Potential Applications

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Journal of Systems Engineering and Electronics 1992年第1期3卷 21-34页

作者： Alfonso farina Flavio A.Studer ALENIA S.p.A. ALENIA S.p.A. Via Tiburtina km. 12.400-00131-Rome-Italy

In a previous companion paper [1], the potential advantages of high resolution radar for improved target detection were introduced. In particular, the concept of shaping both the transmitted waveform and the receiving processor in accordance to the expected target down-range profile was highlighted and performance predictions were provided. In this paper, we present and evaluate an adaptive scheme devised to on-line estimate the target profile, in order to overcome a limited a-priori knowledge. In addition, we introduce a more general model of target impulse response, based on a statistical description, and we discuss the corresponding processing scheme and detection performance.

关键词： High resolution radar Radar detection Adaptive imaging Design criteria.

Classical olfactory conditioning promotes long-term memory and improves odor-cued flight orientation in the South American native bumblebee Bombus pauloensis

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Current Zoology 2021年第5期67卷 561-563页

作者： Denise NERY Florencia PALOTTINI Walter M.farina Laboratorio de Insectos Sociales Departamento de Biodiversidad y Biologia ExperimentalFacultad de Ciencias NaturalesUniversidad de Buenos AiresBuenos AiresArgentina Instituto de Fisiologia Biologia Molecular y Neurociencias(IFIBYNE)CONICET-Universidad de Buenos AiresBuenos AiresArgentina

When collecting a flower,bumblebees learn to associate floral features with reward,preferring,and specializing in the most profitable ones they visit(Chittka et al.1999).The proboscis extension reflex(PER)occurs naturally in the feeding context allowing individuals to access the floral *** controlled conditions,the PER paradigm is a well-established controlled learning procedure used in honeybees(Takeda 1961),and some bumblebees of the genus Bombus(Laloi et al.1999).The assessment of cognitive capacities in an operant context has been studied mainly in *** and ***(Chittka 1998;Mirwan and kevan 2014).However,little is known about the ability to evoke associative memories in an operant context,which had been acquired in a classical *** turn,on the contrary,the Bombus genus also has the capacity to form longterm memories(Chittka 1998;McAulay et al.2015).In particular,the South American bumblebee ***(***)can learn a pure odor when it is presented in a paired association with a sugar reward within a PER paradigm(Palottini et al.2018).As other species,this one is a commercially reared pollinator that is increasingly managed in pollination services of some South American countries and they could be important for increasing production of crops(Palottini et al.2018).

关键词： crops sugar associative

A first comparison of bone histomorphometry in extant domestic horses(Equus caballus)and a Pleistocene Indian wild horse(Equus namadicus)

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Integrative Zoology 2020年第6期15卷 448-460页

作者： Marco ZEDDA Vijay SATHE Prateek CHAkRABORTY Maria Rita PALOMBO Vittorio farina Department of Veterinary Medicine University of SassariItaly Department of AIHC&Archaeology Deccan College Postgraduate and Research InstitutePuneIndia CNR-IGAG c/o Department of Earth SciencesSapienza UniversityRomaItaly

The microstructural features of the tissue of long bones subjected to different biomechanical stresses could be a helpful tool for a better understanding of locomotor behavior in extant and extinct mammals,including ***,few researches have attempted to describe the bone tissue of extinct *** our study,we analyze and compare the histomorphometric features of the bone tissue in extant modern horses,Equus caballus,and Equus namadicus,a Pleistocene Indian extinct wild *** number,position,and size of the osteons and Haversian canals of the bone tissue,classifiable as dense Haversian tissue,were considered for the *** results obtained highlight some differences between the analyzed species,*** having fewer and bigger osteons than *** microstructural differences may depend on the different lifestyles and environmental conditions characterizing the two *** results obtained suggest that comparing the biomechanical properties of extinct and modern horse species may provide indirect information on their paleoenvironment.

关键词： bone tissue Equus caballus Equus namadicus histomorphometry horse

Micro computed tomography based finite element models for elastic and strength properties of 3D printed glass scaffolds

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Acta Mechanica Sinica 2021年第2期37卷 292-306页

作者： Erica farina Dario Gastaldi Francesco Baino Enrica Verne Jonathan Massera Gissur Orlygsson Pasquale Vena Department of Chemistry Materials and Chemical EngineeringPolitecnico di Milano20133 MilanoItaly Department of Applied Science and Technology(DISAT) Politecnico di Torino10129 TurinItaly Tampere University Faculty of Medicine and Health TechnologyTampereFinland Department of Materials Biotechnology and EnergyInnovation Center Iceland(ICI)112 ReykjavikIceland

In this study,the mechanical properties of glass scaffolds manufactured by robocasting are investigated through micro computed tomography(/x-CT)based finite element *** scaffolds are obtained by printing fibers along two perpendicular directions on parallel layers with a 90°tilting between two adjacent layers.A parametric study is first presented with the purpose to assess the effect of the major design parameters on the elastic and strength properties of the scaffold;the mechanical properties of the 3D printed scaffolds are eventually estimated by using the\i-CT data with the aim of assessing the effect of defects on the final geometry which are intrinsic in the manufacturing *** macroscopic elastic modulus and strength of the scaffold are determined by simulating a uniaxial compressive test along the direction which is perpendicular to the layers of the printed *** iterative approach has been used in order to determine the scaffold strength.A partial validation of the computational model has been obtained through comparison of the computed results with experimental values presented in[10]on a ceramic scaffold having the same *** the results have been presented as non-dimensional *** finite element analyses have shown which of the selected design parameters have the major effect on the stiffness and strength,being the porosity and fiber shifting between adjacent layers the most important *** analyses carried out on the basis of the/x-C7 data have shown elastic modulus and strength which are consistent with that found on ideal geometry at similar macroscopic porosity.

关键词： Bioactive glass Scaffold,porosity Finite element model μ-CT

Metamorphism and exhumation of basement gneiss domes in the Quadrilátero Ferrífero:Two stage dome-and-keel evolution?

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Geoscience Frontiers 2019年第5期10卷 1765-1787页

作者： kathryn Cutts Cristiano Lana Fernando Alkmim Federico farina Hugo Moreira Viviane Coelho Applied Isotope Research Group Departamento de GeologiaEscola de MinasUniversidade Federal de Ouro PretoMorro do Cruzeiro35400-000Ouro PretoMGBrazil Department of Earth Sciences University of GenevaRue des Maraihers 131205GenevaSwitzerland School of Earth and Environmental Sciences University of PortsmouthBurnaby BuildingBurnaby RoadPortsmouthPO1 3QLUK

The presence of dome-and-keel provinces in Archean cratons has been connected with the initiation of plate tectonics on Earth as these features are most commonly observed in Archean *** Quadrilátero Ferrífero in Brazil has been identified as a Paleoproterozoic dome-and-keel province for more than three *** prevailing model suggests that it formed during the Rhyacian Transamazonian orogeny,making it unique among dome-and-keel ***,a lack of appropriate lithologies,datable minerals and the metamorphic overprint of later orogenesis has resulted in a cryptic metamorphic record for the formation of this dome-and-keel province.A clinopyroxene-bearing migmatite from the core of the Bacao dome has peak P-T conditions of 5-7 kbar and 700-750 ℃ and a published age of ca.2730 Ma based on U-Pb ages of zircon from leucosomes,suggesting that this age represents the migmatisation event.A fine-grained epidote-albite-titanite assemblage overprints the coarse-grained clinopyroxene and amphibole,giving P-T conditions of 8-9 kbar and 550℃ with an associated titanite age of ca.2050 Ma.A garnet-bearing amphibolite sample also from the core of the dome has peak P-T conditions of 7-8 kbar and 650-700℃,and texturally late titanite from this sample produces an age of ca.2060 *** additional samples were collected from the edges of the dome.A garnet-gedrite bearing felsic schist produces peak P-T conditions of 8-9 kbar and 650-700℃ on a clockwise P-T *** sample has a U-Pb zircon age of ca.2775 Ma,which could date metamorphism or be the age of its volcaniclastic *** unconstrained titanite from the sample gives an age of ca.2040 Ma.A garnet-bearing amphibolite that occurs as a boudin within the felsic schist gives both zircon and titanite ages of ca.2050 Ma and has peak P-T conditions of 5-6 kbar and 650-700 ℃ on a near isobaric P-T *** amphibolite dike,observed to cross-cut the felsic schist produces a zircon U-Pb age of ca.2760 Ma

关键词： Sao Francisco Craton Zircon U-Pb Titanite U-Pb Phase diagrams Dome-and-keel