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Cardiac remodeling in postischemic end-stage human hearts: Involvement of extracellular matrix and angiogenesis-related molecules

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World Journal of Cardiovascular Diseases 2013年第1期3卷 91-99页

作者： Loredana Postiglione Luca De Santo Gaetano Di Spigna Clotilde Castaldo Germano Guerra Paolo Ladogana alessandro arcucci Diego Calabrese Bianca Covelli Serena Vitale Valentina Mele Stefania Montagnani Department of Cardiothoracic Sciences Second University of Naples c/o Monaldi Hospital Naples Italy. Department of Public Health “Federico II” University of Naples Naples Italy Department of Public Health “Federico II” University of Naples Naples Italy. Department of Translational Medical Sciences “Federico II” University of Naples Naples Italy

Background: Extracellular matrix (ECM) participates in heart growth and influences cardiac stem-cell differentiation and migration. The modification of ECM associated with cardiomyopathies is a complex process involving a cohort of proteins. ECM proteins are involved in the regulation of neoangiogenesis in physiological and pathological conditions through their interaction with some angiogenic factors. Our aim was to investigate the role of some angiogenesis-related ECM proteins in the remodeling heart. Methods: We examined cardiac tissue samples from 21 explanted human hearts and 10 non-failing hearts before transplantation. Each specimen was submitted to morphological and biomolecular analysis. Results: We demonstrated a reduced expression of α2-chain laminin mRNA in pathological samples that could play an important role in the progression of cardiac failure by contributing to sarcolemma modifications. Reduced expression of tenascin cytotactin (TN-C) and TN-X in explanted hearts indicated chronic cardiac damage and an impaired capacity to stimulate new vessel development. The observed type IV collagen increase was not related to neoangiogenesis, as reflected by the decreased expression of vascular endothelial growth factor (VEGF)-A and VEGF receptor-2. The inverse correlation between heart dimension and VEGF-A immunopositivity seems particularly interesting. Conclusions: Our findings suggest that ECM reacts strongly to ischemic damage in failing hearts through some important modifications of its protein composition. Nevertheless, this reaction cannot completely restore myocardium structure if it is not supported by adequate neoangiogenesis. The decrease in some ECM proteins related to vessel development has a negative effect on postischemic neoangiogenesis and clinical outcome.

关键词： Heart Failure Cardiac Remodeling Vascular Endothelial Growth Factor Tenascin X α2-Chain Laminin

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A novel solution treatment and aging for powder bed fusion-laser beam Ti-6Al-2Sn-4Zr-6Mo alloy:Microstructural and mechanical characterization

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 414-424页

作者： Gianluca Pirro Alessandra Martucci alessandro Morri Mariangela Lombardi Lorella Ceschini Department of Industrial Engineering(DIN) Alma Mater Studiorum-University of BolognaBologna 40136Italy Department of Applied Science and Technology(DISAT) Politecnico di TorinoTorino TO 10129Italy

Ti-6Al-4Zr-2Sn-6Mo alloy is one of the most recent titanium alloys processed using powder bed fusion-laser beam(PBF-LB)*** alloy has the potential to replace Ti-6Al-4V in automotive and aerospace applications,given its superior mechanical properties,which are approximately 10%higher in terms of ultimate tensile strength(UTS)and yield strength after appropriate heat *** as-built conditions,the alloy is characterized by the presence of soft orthorhombicα″martensite,necessitating a postprocessing heat treatment to decompose this phase and enhance the mechanical properties of the ***,PBFed Ti6246 components undergo an annealing process that transforms theα″martensite into anα-βlamellar *** primary objective of this research was to develop a solution treatment and aging(STA)heat treatment tailored to the unique microstructure produced by the additive manufacturing process to achieve an ultrafine bilamellar microstructure reinforced by precipitation *** study investigated the effects of various solution temperatures in theα-βfield(ranging from 800 to 875℃),cooling media(air and water),and aging time to determine the optimal heat treatment parameters for achieving the desired bilamellar *** each heat treatment condition,differentα-βmicrostructures were found,varying in terms of theα/βratio and the size of the primaryα-phase *** attention was given to how these factors were influenced by increases in solution temperature and how microhardness correlated with the percentage of the metastableβphase present after *** tests were performed on samples subjected to the most promising heat treatment parameters.A comparison with literature data revealed that the optimized STA treatment enhanced hardness and UTS by13%and 23%,respectively,compared with those of the annealed *** surface analyses were conducted to investigate fracture mechanisms.

关键词： powder bed fusion-laser beam titanium alloys heat treatments mechanical properties fractographic analysis

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Coulomb Friction Driving Brownian Motors

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Communications in Theoretical Physics 2014年第10期61卷 505-513页

作者： alessandro Manacorda Andrea Puglisi alessandro Sarracino Dipartimento di Fisica Università "Sapienza"p.le A.Moro 200185 RomeItaly Istituto dei Sistemi Complessi - CNR and Dipartimento di Fisica Università "Sapienza"p.le A.Moro 200185 RomeItaly Kavli Institute for Theoretical Physics China the Chinese Academy of Sciences Laboratoire de Physique Théorique de la Matière Condensée CNRS UMR 7600case courrier 121Université Paris 64Place Jussieu75255 Paris CedexFrance

We review a family of models recently introduced to describe Brownian motors under the influence of Coulomb friction, or more general non-linear friction laws. It is known that, if the heat bath is modeled as the usual Langevin equation(linear viscosity plus white noise), additional non-linear friction forces are not sufficient to break detailed balance, i.e. cannot produce a motor effect. We discuss two possibile mechanisms to elude this problem. A first possibility, exploited in several models inspired to recent experiments, is to replace the heat bath's white noise by a "collisional noise", that is the effect of random collisions with an external equilibrium gas of particles. A second possibility is enlarging the phase space, e.g. by adding an external potential which couples velocity to position, as in a Klein–Kramers equation. In both cases, non-linear friction becomes sufficient to achieve a non-equilibrium steady state and, in the presence of an even small spatial asymmetry, a motor effect is produced.

关键词： Brownian motors ratchet effect Coulomb friction

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A flexible multi-body model of a surface miner for analyzing the interaction between rock-cutting forces and chassis vibrations

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International Journal of Mining Science and Technology 2021年第3期31卷 365-375页

作者： alessandro Medolago Stefano Melzi Tesmec S.p.A. Grassobbio 24050Italy Department of Mechanics Politecnico di MilanoMilano 20156Italy

The discontinuous nature of rock cutting can easily cause unwanted vibrations in the structure of a surface *** these vibrations are not properly addressed,the related stress cycles can gradually damage the chassis resulting in fatigue *** events can seriously undermine the safety of operators and digging operations may be stopped for days,with an obvious economic *** work presents an analysis of the dynamics of a surface miner,focusing on the interaction between cutting machine dynamics and cutting forces,which is a new approach for this type of *** this purpose,the authors developed a numerical model of the cutting process made up of(1)a multi-body model of the cutting machine,which takes into account the chassis's flexibility;(2)a model of the rotating cutting head;and(3)a model of the interaction between the cutting head and rock,based on Shao's *** model was compared with experimental results and then used to investigate the effects of cutting speed and cutting depth on the machine dynamics.

关键词： Surface miner Flexible multi-body model Validation Cutting forces Chassis vibrations

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Spin-phonon decoherence in solid-state paramagnetic defects from first principles

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npj Computational Materials 2023年第1期9卷 1129-1136页

作者： Sourav Mondal alessandro Lunghi School of Physics AMBER and CRANN InstituteTrinity CollegeDublin 2Ireland

Paramagnetic defects in diamond and hexagonal boron nitride possess a combination of spin and optical properties that make them prototypical solid-state *** the coherence of these spin qubits being critically limited by spin-phonon relaxation,a full understanding of this process is not yet *** we apply ab initio spin dynamics simulations to this problem and quantitatively reproduce the experimental temperature dependence of spin relaxation time and spin coherence *** demonstrate that low-frequency two-phonon modulations of the zero-field splitting are responsible for spin relaxation and decoherence,and point to the nature of vibrations in 2-dimensional materials as the culprit for their shorter coherence *** results provide an interpretation to spin-phonon decoherence in solid-state paramagnetic defects,offer a strategy to correctly interpret experimental results,and pave the way for the accelerated design of spin qubits.

关键词： phonon relaxation state

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Matrix Algebras in Non-Hermitian Quantum Mechanics

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Communications in Theoretical Physics 2011年第7期56卷 96-98页

作者： alessandro Sergi School of Physics University of KwaZulu-NatalPietermaritzburg CampusPrivate Bag X01 Scottsville

In principle, non-Hermitian quantum equations of motion can be formulated using as a starting point either the Heisenberg＇s or the Schroedinger＇s picture of quantum dynamics. Here it is shown in both cases how to map the algebra of commutators, defining the time evolution in terms of a non-Hermitian Hamiltonian, onto a non-Hamiltonian algebra with a Hermitian Hamiltonian. The logic behind such a derivation is reversible, so that any Hermitian Hamiltonian can be used in the formulation of non-Hermitian dynamics through a suitable algebra of generalized （non-Hamiltonian） commutators. These results provide a general structure （a template） for non-Hermitian equations of motion to be used in the computer simulation of open quantum systems dynamics.

关键词： non-hermitian quantum mechanics non-Hamiltonian dynamics open quantum systems

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Recent Advances in the Catalytic Functionalization of “Electrophilic” Indoles

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Chinese Journal of Chemistry 2020年第3期38卷 287-294页

作者： alessandro Cerveri Marco Bandini Dipartimento di Chimica"Giacomo Ciamician"-Alma Moter Studiorum Universita di Bologna Via Selmi 240126 BolognaItaly Consorzio C.I.N.M.P.I.S.Via Selmi 2 40126 BolognaItaly

When "dark"is bright:the scarcely explored electrophilic profile of the indolyl core(dark side)continues to inspire developments in organic synthesis by means of new catalytic *** advancements in the field enabled mol... 详细信息

关键词： chemistry. Catalytic heterocyclic

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Cysteine carboxyethylation:a novel post-translational modification associated with autoimmune arthritis

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Signal Transduction and Targeted Therapy 2023年第8期8卷 3561-3562页

作者： alessandro Didonna Department of Anatomy and Cell Biology Brody School of MedicineEast Carolina UniversityGreenvilleNC 27834USA

In a study recently published in Science,Zhai et *** that protein carboxyethylation results in the formation of neoantigens with the ability to trigger autoimmune arthritis in the context of ankylosing spondylitis(AS)pathology.1 This work defines a novel molecular mechanism underlying immune tolerance breakdown,which could serve as a target for innovative therapeutic strategies against AS and other autoimmune disorders.

关键词： autoimmune pathology

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Vibration suppression of speed-controlled robots with nonlinear control

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Frontiers of Mechanical Engineering 2016年第2期11卷 204-212页

作者： Paolo BOSCARIOL alessandro GASPARETTO Dipartimento Politecnico di Ingegneria e Architettura (DPIA) University of Udine Via delle Scienze 206 Udine 33100 Italy

In this paper, a simple nonlinear control strategy for the simultaneous position tracking and vibration damping of robots is presented. The control is developed for devices actuated by speed-controlled servo drives. The conditions for the asymptotic stability of the closed-loop system are derived by ensuring its passivity. The capability of achieving improved trajectory tracking and vibration suppression is shown through experimental tests conducted on a three-axis Cartesian robot. The control is aimed to be compatible with most industrial applications given the simplicity of implementation, the reduced computational requirements, and the use of joint position as the only measured signal.

关键词： industrial robot nonlinear control vibrationdamping model-free control motion control

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Attitude Regulation With Bounded Control in the Presence of Large Disturbances With Bounded Moving Average

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IEEE/CAA Journal of Automatica Sinica 2022年第5期9卷 834-846页

作者： Ang Li alessandro Astolfi Ming Liu School of Astronautics Harbin Institute of TechnologyHarbin 150080China Department of Electrical and Electronic Engineering Imperial College LondonLondon SW72AZUK Dipartimento di Ingegneria Civile e Ingegneria Informatica University of Rome Tor VergataRoma 00133Italy IEEE

The attitude regulation problem with bounded control for a class of satellites in the presence of large disturbances,with bounded moving average,is solved using a Lyapunov-like *** analysis and design approaches are introduced in the case in which the underlying system is an integrator and are then applied to the satellite attitude regulation *** performance of the resulting closed-loop systems are studied in detail and it is shown that trajectories are ultimately bounded despite the effect of the persistent *** results on a model of a small satellite subject to large,but bounded in moving average,disturbances are presented.

关键词： control cubeSats robust attitude regulation ultimate boundedness

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