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Tuning of frictional properties in torsional contact by means of disk grading

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Friction 2022年第5期10卷 787-802页

作者： gianluca COSTAGLIOLA Federico BOSIA Nicola m pUGNO Civil Engineering Institute Ecole Polytechmique Federale de LausamneLausanne 1015Switzerland Department ofApplied Science and Technology Politecnico di TorinoCorso Duca degli Abruzzi 24Torino 10129Italy Laboratory for BioinspiredBionicNanoMeta Materials&MechanicsDepartment of CivilEnvironmental and Mechanical EngineeringUniversity of TrentoTrento 38123Italy School of Engineering and materials Science Queen Mary University of LondonLondon EI 4NSUK

The contact of two surfaces in relative rotating motion occurs in many practical applications,from mechanical devices to human joints,displaying an intriguing interplay of effects at the onset of sliding due to the axisymmetric stress *** and numerical models have been developed for some typical configurations,but work remains to be done to understand how to modify the emergent friction properties in this *** this paper,we extend the two-dimensional(2D)spring-block model to investigate friction between surfaces in torsional *** investigate how the model describes the behavior of an elastic surface slowly rotating over a rigid substrate,comparing results with analytical calculations based on energy *** show that an appropriate grading of the tribological properties of the surface can be used to avoid a non-uniform transition to sliding due to the axisymmetric configuration.

关键词： friction torsion numerical simulations grading

Actin(g) toward a revised understanding of the role of cytoskeletal dynamics in neuronal bioenergetics

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Neural Regeneration Research 2024年第10期19卷 2109-2110页

作者： Sabrina m.Holland gianluca Gallo Department of Neural Sciences Shriners Pediatric Research CenterLewis Katz School of Medicine at Temple UniversityPhiladelphiaPAUSA

Neurons are energy-demanding *** in energy metabolism can quickly interrupt neuronal function,leading to cell death and *** instance,ischemia rapidly depletes adenosine triphosphate(ATp)thereby disrupting energy-dependent cellular processes crucial for homeostasis,and axon degeneration is preceded by a collapse of axonal ATp levels.

关键词： metabolism homeostasis degeneration

BOUNDARY pROCEDURES FOR THE TImE-DEpENDENT BURGERS' EQUATION UNDER UNCERTAINTY

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Acta mathematica Scientia 2010年第2期30卷 539-550页

作者： per pettersson Jan Nordstrm gianluca Iaccarino mechanical Engineering and Institute for Computational mathematical Engineering Stanford University Division of Scientific Computing Department of Information TechnologyUppsala University School of mechanical Industrial and Aeronautical EngineeringUniversity of the Witvatersrand Department of Aeronautics and Systems Integration FOIThe Swedish Defense Research Agency

The Burgers＇ equation with uncertain initial and boundary conditions is approximated using a polynomial Chaos Expansion （pCE） approach where the solution is represented as a series of stochastic, orthogonal polynomials. The resulting truncated pCE system is solved using a novel numerical discretization method based on spatial derivative operators satisfying the summation by parts property and weak boundary conditions to ensure stability. The resulting pCE solution yields an accurate quantitative description of the stochastic evolution of the system, provided that appropriate boundary conditions are available. The specification of the boundary data is shown to influence the solution; we will discuss the problematic implications of the lack of precisely characterized boundary data and possible ways of imposing stable and accurate boundary conditions.

关键词： stochastic Burgers' equation uncertainty quantification polynomial chaos

A Quantitative Comparison of physical Accuracy and Numerical Stability of Lattice Boltzmann Color Gradient and pseudopotential multicomponent models for microfluidic Applications

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Communications in Computational physics 2022年第7期32卷 450-489页

作者： Karun p.N.Datadien gianluca Di Staso Herman m.A.Wijshoff Federico Toschi Department of Applied physics Eindhoven University of Technology5612 AZ EindhovenNetherlands FLOW matters Consultancy B.V. 5612AEEindhovenThe Netherlands Department of mechanical Engineering Eindhoven University of Technology5612 AZ EindhovenNetherlands Canon production printing Netherlands B.V. 5914 HHVenloThe Netherlands Department of mathematics and Computer Science Eindhoven University of Technology5612 AZ EindhovenNetherlands Istituto per le Applicazioni del Calcolo Consiglio Nazionale delle Ricerche00185 RomeItaly

The performances of the Color-Gradient(CG)and the Shan-Chen(SC)multicomponent Lattice Boltzmann models are quantitatively compared side-by-side on multiple physical flow problems where breakup,coalescence and contraction of fluid ligaments are *** flow problems are relevant to microfluidic applications,jetting of microdroplets as seen in inkjet printing,as well as emulsion dynamics.A significantly wider range of parameters is shown to be accessible for CG in terms of density-ratio,viscosity-ratio and surface tension *** stability for a high density ratio O(1000)is required for simulating the drop formation process during inkjet printing which we show here to be achievable using the CG model but not using the SC *** results show that the CG model is a suitable choice for challenging simulations of droplet formation,due to a combination of both numerical stability and physical *** also present a novel approach to incorporate repulsion forces between interfaces for CG,with possible applications to the study of stabilized ***,we show that the CG model can produce similar results to a known multirange potentials extension of the SC model for modelling a disjoining pressure,opening up its use for the study of dense stabilized emulsions.

关键词： Lattice Boltzmann method multiphase flow multicomponent flow inkjet printing turbulent emulsion

Collagen-based biological glue after Appleby operation for advanced gastric cancer

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World Journal of Gastroenterology 2011年第35期17卷 4044-4047页

作者： gianluca Baiocchi Nazario portolani Federico Gheza Stefano m Giulini Department of medical and Surgical Sciences Surgical Clinic Brescia University25127 Brescia Italy

pancreatic fistula is a common complication of distal pancreatectomy; although various surgical procedures have been proposed, no clear advantage is evident for a single technique. We herein report the case of a 38-year-old patient affected by an advanced gastric carcinoma infiltrating the pancreas body, with exten- sive nodal metastases involving the celiac trunk, who underwent total gastrectomy with lymphadenectomy, distal pancreatectomy and resection en bloc of the celiac trunk (Appleby operation). At the end of the demolitive phase, the pancreatic stump and the aorta at the level of the celiac ligature were covered with a layer of Tachosil, a horse collagen sponge made with human coagulation factors (fibrinogen and thrombin). presenting this case, we wish to highlight the possible sealing effect of this product and hypothesize a role in preventing pancreatic fistula and postoperative lymphorrhagia from extensive nodal dissection.

关键词： Gastric cancer pancreatic fistula Vascular infiltration Biologic sealant

Comparison of Lattice Boltzmann,Finite Element and Volume of Fluid multicomponent methods for microfluidic Flow problems and the Jetting of microdroplets

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Communications in Computational physics 2023年第3期33卷 912-936页

作者： Karun p.N.Datadien gianluca Di Staso Christian Diddens Herman m.A.Wijshoff Federico Toschi Department of Applied physics and Science Education Eindhoven University of Technology5600MB EindhovenNetherlands FLOW matters Consultancy B.V. 5612AEEindhovenThe Netherlands physics of Fluids group Department of Science and TechnologyMesa+InstituteMax Planck Center for Complex Fluid Dynamics and J.M.Burgers Centre for Fluid DynamicsUniversity of TwenteP.O.Box 2177500 AE EnschedeThe Netherlands Canon production printing Netherlands B.V. 5914 HHVenloThe Netherlands Department of mathematics and Computer Science Eindhoven University of Technology5600MB EindhovenNetherlands Istituto per le Applicazioni del Calcolo Consiglio Nazionale delle Ricerche00185 RomeItaly.

We show that the lattice Boltzmann method(LBm)based color-gradient model with a central moments formulation(CG-Cm)is capable of accurately simulating the droplet-on-demand inkjetting process on a micrometer length scale by comparing it to the Arbitrary Lagrangian Eulerian Finite Element method(ALE-FEm).A full jetting cycle is simulated using both CG-Cm and ALE-FEmand results are quantitatively compared by measuring the ejected ink velocity,volume and contraction *** also show that the individual relevant physical phenomena are accurately captured by considering three test-cases;droplet oscillation,ligament contraction and capillary *** first two cases test accuracy for a dynamic system where surface tension is the driving force and the third case is designed to test wetting boundary *** the first two cases we also compare the CG-Cm and ALE-FEm results to Volume of Fluid(VOF)*** of the three methods shows close agreement when compared to each other and analytical solutions,where *** we demonstrate that asymmetric jetting is achievable using 3D CG-Cm simulations utilizing asymmetric wetting conditions inside the *** allows for systematic investigation into the physics of asymmetric jetting,*** to jet-nozzle manufacturing imperfections or due to other disturbances.

关键词： Lattice Boltzmann method multiphase flow multicomponent flow inkjet printing

Effect of operating temperature on aged single lap bonded joints

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Defence Technology（防务技术） 2020年第2期16卷 283-289页

作者： Costanzo Bellini gianluca parodo Luca Sorrentino Department of Civil and mechanical Engineering University of Cassino and Southern LazioCassino FR03043Italy

In recent decades,designers have increasingly focused on the stability of assemblies in composite materials over time,particularly when used in structural *** use of structural adhesives allows for realising assemblies without mechanical *** fact,bonding is an assembly technique that prevent corrosion,ensures uniform stresses in the joint,and grows the specific resistance of the *** knowledge of the behaviour of bonded joint is necessary to ensure the reliability of this technique over time,especially in aggressive *** aim of this wo rk consists in investigating the combined effect of hydrothermal ageing and temperature test on the lap shear strength of single lap joints realised in *** results showed a higher influence of the ageing on paste adhesive compared to film ***,the ageing,combined with the operating temperature,played a fundamental role on the shear strength of the bonded joints.

关键词： Temperature tests Hydrothermal ageing Adhesive bonding Single lap joint Experimental tests

Biofabrication of nanocomposite-based scaffolds containing human bone extracellularmatrix for the differentiation of skeletal stem and progenitor cells

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Bio-Design and manufacturing 2024年第2期7卷 121-136页

作者： Yang-Hee Kim Janos m.Kanczler Stuart Lanham Andrew Rawlings marta Roldo gianluca Tozzi Jonathan I.Dawson gianluca Cidonio Richard O.C.Oreffo Faculty of medicine Bone and Joint Research GroupCentre for Human DevelopmentStem Cells and RegenerationInstitute of Developmental SciencesUniversity of SouthamptonSouthampton SO166YDUK School of pharmacy and Biomedical Science University of PortsmouthPortsmouth PO12DTUK School of Engineering Faculty of Engineering and ScienceUniversity of GreenwichGreenwich ME44TBUK Center for Life Nano-and Neuro-Science(CLN2S) Italian Institute of Technology00161 RomeItaly

Autograft or metal implants are routinely used in skeletal ***,they fail to provide long-term clinical resolution,necessitating a functional biomimetic tissue engineering *** use of native human bone tissue for synthesizing a biomimeticmaterial inkfor three-dimensional(3D)bioprintingof skeletal tissueis anattractivestrategyfor ***,human bone extracellular matrix(bone-ECm)offers an exciting potential for the development of an appropriate microenvironment for human bone marrow stromal cells(HBmSCs)to proliferate and differentiate along the osteogenic *** this study,we engineered a novel material ink(LAB)by blending human bone-ECm(B)with nanoclay(L,Laponite®)and alginate(A)polymers using extrusion-based *** inclusion of the nanoﬁller and polymeric material increased the rheology,printability,and drug retention properties and,critically,the preservation of HBmSCs viability upon *** composite of human bone-ECm-based 3D constructs containing vascular endothelial growth factor(VEGF)enhanced vascularization after implantation in an ex vivo chick chorioallantoic membrane(CAm)*** inclusion of bone morphogenetic protein-2(Bmp-2)with the HBmSCs further enhanced vascularization and mineralization after only seven *** study demonstrates the synergistic combination of nanoclay with biomimetic materials(alginate and bone-ECm)to support the formation of osteogenic tissue both in vitro and ex vivo and offers a promising novel 3D bioprinting approach to personalized skeletal tissue repair.

关键词： Extracellular matrix Nanoclay Bone 3D bioprinting

protein Domains Involved in Assembly in the Endoplasmic Reticulum promote Vacuolar Delivery when Fused to Secretory GFp, Indicating a protein Quality Control pathway for Degradation in the plant Vacuole

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molecular plant 2008年第6期1卷 1067-1076页

作者： Ombretta Foresti Francesca De marchis maddalena de virgilio Eva m. Klein Sergio Arcioni michele Bellucci Alessandro Vitale Istituto di Biologia e Biotecnologia Agraria Consiglio Nazionale delle Ricerche via Bassini 15 20133 Milano Italy EU Istituto di Genetica Vegetale Consiglio Nazionale delle Ricerche via della Madonna Alta 130 06128 Perugia Italy EU

The correct folding and assembly of newly synthesized secretory proteins are monitored by the protein quality control system of the endoplasmic reticulum （ER）. Through interactions with chaperones such as the binding protein （Bip） and other folding helpers, quality control favors productive folding and sorts for degradation defective proteins. A major route for quality control degradation identified in yeast, plants, and animals is constituted by retrotranslocation from the ER to the cytosol and subsequent disposal by the ubiquitin/proteasome system, but alternative routes involving the vacuole have been identified in yeast. In this study, we have studied the destiny of sGFp418, a fusion between a secretory form of GFp and a domain of the vacuolar protein phaseolin that is involved in the correct assembly of phaseolin and in Bip recognition of unassembled subunits. We show that sGFp418, despite lacking the phaseolin vacuolar sorting signal, is delivered to the vacuole and fragmented, in a process that is inhibited by the secretory traffic inhibitor brefeldin A. moreover, a fusion between GFp and a domain of the maize storage protein γ-zein involved in zein polymerization also undergoes post-translational fragmentation similar to that of sGFp418. These results show that defective secretory proteins with permanently exposed sequences normally involved in oligomerization can be delivered to the vacuole by secretory traffic. This strongly suggests the existence of a plant vacuolar sorting mechanism devoted to the disposal of defective secretory proteins.

关键词： Endoplasmic reticulum protein degradation protein traffic vacuole.