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A network of sex and competition： The promiscuous mating system of an invasive weevil

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Current Zoology 2015年第1期61卷 85-97页

作者： Alberto Francesco INGHILESI Giuseppe MAZZA Rita CERVO alessandro cini Department of Biology University of Florence Via Romana 17 50125 Florence Italy Agricultural Research Council Research Centre for Agrobiology and Pedology via Lanciola 12/A Cascine del Riccio 50125 Florence Italy Department of Biology University of Florence Via Madonna del Piano 6 50019 Sesto Fiorentino Florence Italy Corpo Forestale dello Stato Centro Nazionale Biodiversit~t Forestale "Bosco Fontana"Via C. Ederle 16/a 37100 Verona Italy

Invasive alien pest insect species represent a major threat for agriculture and biodiversity. Because chemical treatments employed to contrast such pests elicit serious environmental and human health problems, a great effort is currently directed to develop long term and environmentally friendly biological control strategies. However, the successful application of some promising techniques, such as the Sterile Insect Technique （SIT）, requires a deep knowledge of the pest basic biology. Here, we argue that understanding pest sexual biology using a social network approach can significantly improve the performance of con- trol strategies. For example, SIT may benefit from understanding how individuals interact and how males accede to reproduction, in order to target the most reproductively active and polygamic males. In this paper we studied the socio-sexual networks of the Asian red palm weevil （RPW） Rhynchophorusferrugineus, a worldwide invader which is causing heavy economic impacts on several palm species. We found that the RPW has a highly promiscuous mating system, characterized by forced interruptions of pair copulations by additional males. The social network is highly non-random nor regular： few males almost monopolize repro- duction, behaving as key-players in the network of matings. Additionally, males have a stable pattern of sexual behaviour over time. We use RPW social network as a case study to direct the development of management techniques such as SIT strategy [Current Zoology 61 （1）： 85-97, 2015].

关键词： Social network analysis Pest management Mating system Reproductive skew Alien pest Rhynchophorusferrugineus

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

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

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

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

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

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

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

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