5,919 research outputs found

    The p-weak gradient depends on p

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    Given \u3b1 > 0, we construct a weighted Lebesgue measure on Rnfor which the family of nonconstant curves has p-modulus zero for p 64 1 + \u3b1 but the weight is a Muckenhoupt Ap weight for p > 1 + \u3b1. In particular, the p-weak gradient is trivial for small p but nontrivial for large p. This answers an open question posed by several authors. We also give a full description of the p-weak gradient for any locally finite Borel measure on R

    New characterizations of Sobolev metric spaces

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    We provide new characterizations of Sobolev ad BV spaces in doubling and Poincar\ue9 metric spaces in the spirit of the Bourgain\u2013Brezis\u2013Mironescu and Nguyen limit formulas holding in domains of R^N

    The five gradients inequality on differentiable manifolds

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    The goal of this paper is to derive the so-called five gradients inequality for optimal transport theory for general cost functions on two class of differentiable manifolds: locally compact Lie groups and compact Riemannian manifolds with Ricci curvature bounded from below.Comment: 29 page

    Pathophysiology of Peripheral Arterial Disease (PAD): A Review on Oxidative Disorders

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    Peripheral arterial disease (PAD) is an atherosclerotic disease that affects a wide range of the world's population, reaching up to 200 million individuals worldwide. PAD particularly affects elderly individuals (>65 years old). PAD is often underdiagnosed or underestimated, although specificity in diagnosis is shown by an ankle/brachial approach, and the high cardiovascular event risk that affected the PAD patients. A number of pathophysiologic pathways operate in chronic arterial ischemia of lower limbs, giving the possibility to improve therapeutic strategies and the outcome of patients. This review aims to provide a well detailed description of such fundamental issues as physical exercise, biochemistry of physical exercise, skeletal muscle in PAD, heme oxygenase 1 (HO-1) in PAD, and antioxidants in PAD. These issues are closely related to the oxidative stress in PAD. We want to draw attention to the pathophysiologic pathways that are considered to be beneficial in order to achieve more effective options to treat PAD patients

    Multimarginal Optimal Transport Maps for one dimensional Repulsive Costs

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    We study a multimarginal optimal transportation problem in one dimension. For a symmetric, repulsive cost function, we show that given a minimizing transport plan, its symmetrization is induced by a cyclical map, and that the symmetric optimal plan is unique. The class of costs that we consider includes, in particular, the Coulomb cost, whose optimal transport problem is strictly related to the strong interaction limit of Density Functional Theory. In this last setting, our result justifies some qualitative properties of the potentials observed in numerical experiments

    Multimarginal Optimal Transport Maps for 1-Dimensional Repulsive Costs

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    The 15-minute city concept and new working spaces: A planning perspective from Oslo and Lisbon

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    In the last few years, chrono-urbanism has welcomed a novel perspective, namely, that of the 15-minute city concept, which has recently emerged in the present planning debate. During the current pandemic, this has coincided with a drive to highlight the importance of merging more activities in the neighbourhood to improve urban vitality and reduce daily commuting. In addition, increasing digitalization and knowledge-intensive activities have transformed the nature of work itself, thus affecting the choice of the workplace with new working spaces (NWS) emerging for collaborative and flexible work environments. Therefore, within this context, this study discusses recent chrono-urbanism approaches applied to urban planning and the role of NWS. The phenomenon is empirically examined in Oslo and Lisbon through a qualitative analysis of planning documents and a spatial analysis. The results show that most NWS are fairly accessible by public transport to users in both cities; although the NWS neighbourhoods in Lisbon have a greater diversity of functions compared to Oslo. However, in both cities, the distribution of NWS is non-uniform. This may limit residents’ choice to live and work (outside home) in the same neighbourhood. The study contributes to the current planning debate on new urban models for sustainable neighbourhoods.info:eu-repo/semantics/publishedVersio

    Hybrid cities and new working spaces – The case of Oslo

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    Recent decades have seen the emergence of hybrid models of living and working associated typologies. These developments have been analysed from the perspective of different disciplines, each with their own interpretation of this phenomenon. Planning and architecture have addressed hybridization as a specific form of interaction between spatio-functional features (such as mixed use, multi-functionality and flexibility) and social features (such as formal and informal interactions and the spontaneous appropriation of spaces) or have sometimes simply focused on the spatio-functional dimension in urban spaces. Studies from other disciplines (e.g. mobility networks, transportation, sociology and information technology) have shown that hybrid spaces cannot exist without access to digitalization technologies. Such technologies are accelerating hybridization processes. This study examines the complex and layered phenomenon of hybridization as a possible combination of (or interaction between) spatio-functional, social and digital features within the planning debate and related fields. Most of the case studies explored by scholars so far have focused on interactions occurring between residential, social and recreational functions, but working functions are playing an increasingly important role. Furthermore, the COVID-19 pandemic has accelerated the development of new forms of hybridity in cities. As a consequence, the rising use of hybrid (on-site and on-line) working practices, planners, policy makers and stakeholders, as well as scholars, have increasingly discussed the concept of hybridization. In this context, various hybrid typologies of urban spaces have materialized in forms such as new working spaces (NWS) which include co-working spaces, incubators, as well as some cafés and multi-functional public libraries, which have recently provided working spaces. This paper focuses on the evolving concept of hybridity from the planning perspective. Based on five hybrid NWS including their surrounding neighbourhoods in Oslo, it provides empirical evidence for an understanding of the phenomenon that may support the development of hybrid spaces and buildings and develops suggestions for planning strategies. © 2022 The Author

    Seismic Vulnerability Analysis of a Coupled Tank-Piping System by Means of Hybrid Simulation and Acoustic Emission

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    AbstractIn order to shed light on the seismic response of complex industrial plants, advanced finite element models should take into account both multicomponents and relevant coupling effects. These models are usually computationally expensive and rely on significant computational resources. Moreover, the relationships between seismic action, system response and relevant damage levels are often characterized by a high level of nonlinearity, which requires a solid background of experimental data. Vulnerability and reliability analyses both depend on the adoption of a significant number of seismic waveforms that are generally not available when seismic risk evaluation is strictly site-specific. In addition, detection of most vulnerable components, i.e., pipe bends and welding points, is an important step to prevent leakage events. In order to handle these issues, a methodology based on a stochastic seismic ground motion model, hybrid simulation and acoustic emission is presented in this paper. The seismic model is able to generate synthetic ground motions coherent with site-specific analysis. In greater detail, the system is composed of a steel slender tank, i.e., the numerical substructure, and a piping network connected through a bolted flange joint, i.e., the physical substructure. Moreover, to monitor the seismic performance of the pipeline and harness the use of sensor technology, acoustic emission sensors are placed through the pipeline. Thus, real-time acoustic emission signals of the system under study are acquired using acoustic emission sensors. Moreover, in addition to seismic events, also a severe monotonic loading is exerted on the physical substructure. As a result, deformation levels of each critical component were investigated; and the processing of acoustic emission signals provided a more in-depth view of the damage of the analysed components

    A Movement-Tremors Recorder for Patients of Neurodegenerative Diseases

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    Neurodegenerative diseases such as Alzheimer, Parkinson, motor neuron, and Chorea affect millions of people today. Their effect on the central nervous system causes the loss of brain functions as well as motor disturbances and sometimes cognitive deficits. In such a scenario, the monitoring and evaluation of early symptoms are mandatory for the improvement of the patient's quality of life. Here, the authors describe the development, the laboratory calibration, and the "in-field validation" under the medical supervision of a movement tremors recorder for subjects affected by neurodegenerative diseases. The developed device is based on an array of four accelerometers connected to an embedded development board. This system is able to monitor tremor/movement, accidental falls, and, moreover, it can track the Alzheimer subjects' geographical position. A remote supervisor can collect data from the system through Bluetooth, Wi-Fi, or GSM connections. A data compression algorithm was developed directly on board in order to increase the efficiency of data transmission and reduce power consumptions
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