Effective thermal dynamics following a quantum quench in a spin chain

We study the nonequilibrium dynamics of the Quantum Ising Model following an abrupt quench of the transverse field. We focus on the on-site autocorrelation function of the order parameter, and extract the phase coherence time $\tau^{\phi}_Q$ from its asymptotic behavior. We show that the initial state determines $\tau^{\phi}_Q$ only through an effective temperature set by its energy and the final Hamiltonian. Moreover, we observe that the dependence of $\tau^{\phi}_Q$ on the effective temperature fairly agrees with that obtained in thermal equilibrium as a function of the equilibrium temperature.Comment: 4 pages, 4 figures. Published versio

Matrix Product State representation for Slater Determinants and Configuration Interaction States

Slater determinants are product states of filled quantum fermionic orbitals. When they are expressed in a configuration space basis chosen a priori, their entanglement is bound and controlled. This suggests that an exact representation of Slater determinants as finitely-correlated states is possible. In this paper we analyze this issue and provide an exact Matrix Product representation for Slater determinant states. We also argue possible meaningful extensions that embed more complex configuration interaction states into the description.Comment: 16 pages, 4 figures. Published in IJMPB, focus issue on "Classical vs. Quantum Correlations in Composite Systems

Adaptive Probabilistic Flooding for Multipath Routing

In this work, we develop a distributed source routing algorithm for topology discovery suitable for ISP transport networks, that is however inspired by opportunistic algorithms used in ad hoc wireless networks. We propose a plug-and-play control plane, able to find multiple paths toward the same destination, and introduce a novel algorithm, called adaptive probabilistic flooding, to achieve this goal. By keeping a small amount of state in routers taking part in the discovery process, our technique significantly limits the amount of control messages exchanged with flooding -- and, at the same time, it only minimally affects the quality of the discovered multiple path with respect to the optimal solution. Simple analytical bounds, confirmed by results gathered with extensive simulation on four realistic topologies, show our approach to be of high practical interest.Comment: 6 pages, 6 figure

Long time dynamics following a quench in an integrable quantum spin chain: local versus non-local operators and effective thermal behavior

We study the dynamics of the quantum Ising chain following a zero-temperature quench of the transverse field strength. Focusing on the behavior of two-point spin correlation functions, we show that the correlators of the order parameter display an effective asymptotic thermal behavior, i.e., they decay exponentially to zero, with a phase coherence rate and a correlation length dictated by the equilibrium law with an effective temperature set by the energy of the initial state. On the contrary, the two-point correlation functions of the transverse magnetization or the density-of-kinks operator decay as a power-law and do not exhibit thermal behavior. We argue that the different behavior is linked to the locality of the corresponding operator with respect to the quasi-particles of the model: non-local operators, such as the order parameter, behave thermally, while local ones do not. We study which features of the two-point correlators are a consequence of the integrability of the model by analizing their robustness with respect to a sufficiently strong integrability-breaking term.Comment: 18 pages, 11 figures, published version. Extensive changes, one author adde

Le tecnologie assistive per la disabilità. Dall’assistenza protesica alla promozione delle abilità e dell’inclusione. Quale ruolo può svolgere il disability manager?

To date, WHO estimates that more than one billion people need assistive technology, but that only 10% of them have access to it. The article aims to analyze the current model of territorial prosthetic assistance, highlighting all the epistemological-cultural and practical difficulties that the Local Health Authorities and the professionals involved in the process are forced to face. The Disability Manager can better organize the prescriptive process with the aim of improving the user-centred choice of the aid, avoiding its abandonment, controlling its psycho-educational impact on the person's life. The paper highlights the need to think about a shift of focus: from the device for the deficit to the tool to solicit new skills and promotes inclusion; from "aid" to cultural device for the promotion of biopsy-chosocial well-being

Chapter Leveraging Internet-of-Things to Support Circular Economy Paradigm in Manufacturing Industry

Circular economy represents a fundamental alternative to the currently predominating linear economy model, while Industry 4.0 is a technological enabler to bring process innovation in the industrial domain. New economic models are needed in order to reduce material inputs and waste generation leveraging on ecodesign, recycling and reusing of products, new business models, and new technologies. Internet-of-Things and artificial intelligence can support the circular economy paradigm, through the development of a marketplace for connecting buyers and sellers of manufacturing services, raw materials and products toward building global supply chains. The core component of this marketplace is a novel, agent-based, brokering module that will apply both syntactic and semantic matching in terms of manufacturing capabilities, in order to find the best possible supplier to fulfill a request for a service, raw materials or products involved in the supply chain

Leveraging Internet-of-Things to Support Circular Economy Paradigm in Manufacturing Industry

Circular economy represents a fundamental alternative to the currently predominating linear economy model, while Industry 4.0 is a technological enabler to bring process innovation in the industrial domain. New economic models are needed in order to reduce material inputs and waste generation leveraging on ecodesign, recycling and reusing of products, new business models, and new technologies. Internet-of-Things and artificial intelligence can support the circular economy paradigm, through the development of a marketplace for connecting buyers and sellers of manufacturing services, raw materials and products toward building global supply chains. The core component of this marketplace is a novel, agent-based, brokering module that will apply both syntactic and semantic matching in terms of manufacturing capabilities, in order to find the best possible supplier to fulfill a request for a service, raw materials or products involved in the supply chain

Recurrence of immunoglobulin A nephropathy after kidney transplantation: a narrative review on incidence, risk factors, pathophysiology and management of immunosuppressive therapy

Abstract Glomerulonephritis (GN) is the underlying cause of end-stage renal failure in 30–50% of kidney transplant recipients. It represents the primary cause of end-stage renal disease for 25% of the dialysis population and 45% of the transplant population. For patients with GN requiring renal replacement therapy, kidney transplantation is associated with superior outcomes compared with dialysis. Recurrent GN was previously considered to be a minor contributor to graft loss, but with the prolongation of graft survival, the effect of recurrent disease on graft outcome assumes increasing importance. Thus the extent of recurrence of original kidney disease after kidney transplantation has been underestimated for several reasons. This review aims to provide updated knowledge on one particular recurrent renal disease after kidney transplantation, immunoglobulin A nephropathy (IgAN). IgAN is one of the most common GNs worldwide. The pathogenesis of IgAN is complex and remains incompletely understood. Evidence to date is most supportive of a several hit hypothesis. Biopsy is mandatory not only to diagnose the disease in the native kidney, but also to identify and characterize graft recurrence of IgAN in the kidney graft. The optimal therapy for IgAN recurrence in the renal graft is unknown. Supportive therapy aiming to reduce proteinuria and control hypertension is the mainstream, with corticosteroids and immunosuppressive treatment tailored for certain subgroups of patients experiencing a rapidly progressive course of the disease with active lesions on renal biopsy and considering safety issues related to infectious complications