528 research outputs found

    Participation, growth and social poverty: social capital in a homogeneous society

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    We introduce social capital accumulation into a neoclassical model, showing how it differs from physical and human capital accumulation. We take the view that social capital is crucial to the enjoyment of socially provided goods and that it is mainly accumulated by means of participation to social activities. Under-investment in social capital maylead a growing economy to fall into a social poverty trap. We argue that this risk is particularly relevant for advanced societies.Social capital; self-protection choices; social poverty traps

    Economic Growth and Social Poverty: The Evolution of Social Participation

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    We develop an evolutionary model of growth in which agents choose how to allocate their time between private and social activities. We argue that a shift from social to private activities may foster market-based growth, but also generate social poverty. Within a formal framework that merges a game theoretic analysis of the evolution of social participation with a model of dynamic accumulation of its effects on social environment (i.e., of social capital accumulation), we show that growth and well-being may evolve in opposite directions (a plausible outcome for advanced and affluent societies).Time Allocation, Social Capital, Relational Goods

    Social capital accumulation and the evolution of social partecipation

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    We study the co-evolution of social participation and social capital accumulation, taking the view that the former contributes to the latter, and both contribute to the enjoyment of relational goods Within this framework, we show that a process of substitution of private for social activities (observable in some advanced, affluent economies), might be self-reinforcing and lead to a Pareto-dominated steady state. We find some scope for policy intervention, but we also acknowledge its difficulty.Social Capita; Well-being; Time Allocation

    Lifelong vaccination as a key disease-prevention strategy

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    AbstractVaccination is traditionally considered as a measure addressed to infants and children. Indeed, in natural conditions, vaccine-preventable infections are mainly spread at a young age. The implementation of routine and mass vaccination programmes has led to the eradication of smallpox and to the elimination of poliomyelitis in many regions of the world, together with the control of once life-threatening diseases like diphtheria and tetanus. In more recent times, the development of new generation vaccines and the changing epidemiological profile of many vaccine-preventable diseases have greatly changed the objectives and the target of today’s immunization strategies. The objective of this article is to highlight and discuss the evolution of vaccination strategies from measures aimed at protecting children to a practice that is needed throughout life. Adolescents and adults need immunization for several reasons: they may not have received the vaccines usually administered in childhood; new vaccines tailored for adolescents and adults have become available; immunity acquired thanks to immunization in childhood can fade; and older adults or those who are chronically ill are more susceptible to vaccine-preventable diseases and to their complications. The changing demographic profile of both industrialized countries and of countries in transition towards an ‘aging’ population, and the shift of several infectious diseases towards adulthood make it imperative that new infrastructures to deliver vaccines and new investments in immunization are investigated. Such a change of perspective is needed both to preserve health and to guarantee the sustainability of health systems

    Sustainable Task Offloading in UAV Networks via Multi-Agent Reinforcement Learning

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    The recent growth of IoT devices, along with edge computing, has revealed many opportunities for novel applications. Among them, Unmanned Aerial Vehicles (UAVs), which are deployed for surveillance and environmental monitoring, are attracting increasing attention. In this context, typical solutions must deal with events that may change the state of the network, providing a service that continuously maintains a high level of performance. In this paper, we address this problem by proposing a distributed architecture that leverages a Multi-Agent Reinforcement Learning (MARL) technique to dynamically offload tasks from UAVs to the edge cloud. Nodes of the system co-operate to jointly minimize the overall latency perceived by the user and the energy usage on UAVs by continuously learning from the environment the best action, which entails the decision of offloading and, in this case, the best transmission technology, i.e., Wi-Fi or cellular. Results validate our distributed architecture and show the effectiveness of the approach in reaching the above targets

    Suspension design of a Formula Student single-seater race car

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    Il lavoro di tesi consiste nella progettazione del sistema sospensivo e di sterzo di una monoposto da corsa Formula Student. La tesi è stata svolta in collaborazione con il Greenteam dell'univeristà di stoccarda, per mezzo di un' esperienza Erasmus

    Flow simulations with ultra-low Reynolds numbers over rigid and flexible airfoils subject to heaving and flapping motions

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    Numerical simulations of flow patterns at ultra-low Reynolds numbers over rigid and flexible airfoils and the influence of flexibility on main aerodynamic properties, are presented and discussed. Typical unsteady flights like heaving and flapping are, in terms of Reynolds and Strouhal numbers, reduced frequencies and FSI (Fluid Structure Interaction) factor, are valuated. It has been found that for some flexibility levels, the aerodynamic forces and propulsive efficiency are enhanced if compared with a rigid airfoil. The mathematical technical approach used to solve the laminar-incompressible flow equations coupled with structural algorithms, is described.Fil: Antonelli, Dino Paolo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Aeronáutica; ArgentinaFil: Sacco, Carlos Gustavo. Instituto Universitario Aeronautico; ArgentinaFil: Tamagno, Jose Pedro. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Departamento de Aeronáutica; Argentin

    Factors affecting injury severity among recreational skiers and snowboarders: an epidemiology study

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    Different results have been reported for skiing and snowboarding injuries worldwide. Few studies consider the injury severity score (ISS) for the evaluation of differences among injured skiers–snowboarders. The aim of this study is to identify possible risk factors that affect the severity of skiing and snowboarding injuries in three winter seasons (2002–2005) in South Tyrol. For every injured skier or snowboarder referred to our emergency department in three consecutive seasons, the following data were collected: date of birth, gender, self-declared technical skills level, place of residence (local/non-local), as well as the date, time, and place of the accident. Type of injury and ISS were retrospectively assigned. Data concerning the snowfall in the last 24 h, average snow level, and outdoor air temperature values were obtained from four weather stations that were located inside the ski resorts. A multiple linear regression model was used to evaluate the association between ISS and potential determinants. In the analyzed seasons, 2,511 injured skiers and 843 injured snowboarders were evaluated at our emergency department. There was a significant change in the ISS value for subjects with different self-reported skills levels (P.001). Men and non-local residents experienced more severe injuries than women and local residents, respectively (P.013, P.001). The ISS was higher for people aged over 60 (P.001). Snowfalls brought about a decrease in accident severity (P = 0.009). The severity of the injuries increases with age. Prevention and information programs should be targeted to people who are at high risk of severe injury. A 24-h fresh snowfall seems to reduce the severity of injuries. Very little is known about snow conditions and winter sports injury. Further studies are needed to explore this field

    Guideline on the use of onabotulinumtoxinA in chronic migraine. a consensus statement from the European Headache Federation

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    OnabotulinumtoxinA is being increasingly used in the management of chronic migraine (CM). Treatment with onabotulinumtoxinA poses challenges compared with traditional therapy with orally administered preventatives. The European Headache Federation identified an expert group that was asked to develop the present guideline to provide recommendations for the use of onabotulinumtoxinA in CM. The expert group recommend onabotulinumtoxinA as an effective and well-tolerated treatment of CM. Patients should preferably have tried two to three other migraine prophylactics before start of onabotulinumtoxinA. Patients with medication overuse should be withdrawn from the overused medication before initiation of onabotulinumtoxinA if feasible, if not onabotulinumtoxinA can be initiated from the start or before withdrawal. OnabotulinumtoxinA should be administered according to the PREEMPT injection protocol, i.e. injecting 155 U-195 U to 31-39 sites every 12-weeks. We recommend that patients are defined as non-responders, if they have less than 30% reduction in headache days per month during treatment with onabotulinumtoxinA. However other factors such as headache intensity, disability and patient preferences should also be considered when evaluating response. Treatment should be stopped, if the patient does not respond to the first two to three treatment cycles. Response to continued treatment with onabotulinumtoxinA should be evaluated by comparing the 4 weeks before with the 4 weeks after each treatment cycle. It is recommended that treatment is stopped in patients with a reduction to less than 10 headache days per month for 3 months and that patients are re-evaluated 4-5 months after stopping onabotulinumtoxinA to make sure that the patient has not returned to CM. Questions regarding efficacy and tolerability of onabotulinumtoxinA could be answered on the basis of scientific evidence. The other recommendations were mainly based on expert opinion. Future research on the treatment of CM with onabotulinumtoxinA may further improve the management of this highly disabling disorder
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