1,249 research outputs found

    Gallbladder cancer: South American experience

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    Large differences in terms of incidence and mortality due to gallbladder cancer (GBC) have been reported worldwide. Moreover, it seems that GBC has unique characteristics in South America. We surveyed the literature looking for information about the epidemiology, basic and translational research, and clinical trials performed in South America in order to critically analyze the magnitude of this health problem in the region. Compared to other geographic areas, age-standardized mortality rates (ASMR) for GBC in women are very high, particularly in many western areas of South America. Genetic, as well as dietary and environmental factors likely contribute to the pathogenesis of this disease in the area. Compared to other regions the profile of abnormalities of key genes such as KRAS and TP53 in GBC seems to slightly differ in South America, while the clinical behavior appears to be similar with a median overall survival (OS) of 6.5 to 8 months in advanced GBC. In contrast to Europe and USA, prophylactic cholecystectomy is a common practice in western areas of South America. GBC particularly affects women in South America, and represents a significant public health problem. It appears to have peculiarities that pose an urgent need for additional research aimed to discover risk factors, molecular events associated with its development and new treatment options for this lethal disease.Fil: Arroyo, Gerardo F.. Intergrupo Latinoamericano de Oncología Gastrointestinal; ArgentinaFil: Gentile, Alberto. Provincia de Salta. Ministerio de Salud Pública; ArgentinaFil: Parada, Luis Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; Argentin

    Internet of things: why we are not there yet

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    Twenty-one years past since Weiser’s vision of ubiquitous computing (UbiComp) has been written, and it is yet to be fully fulfilled despite of almost all the needed technologies already available. Still, the widespread interest in UbiComp and the results in some of its fields pose a question: why we are not there yet? It seems we miss the ‘octopus’ head. In this paper, we will try to depict the reasons why we are not there yet, from three different points of view: interaction media, device integration and applications

    Cognitive Robots and the Conscious Mind: A Review of the Global Workspace Theory

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    Abstract Purpose of Review The theory of consciousness is a subject that has kept scholars and researchers challenged for centuries. Even today it is not possible to define what consciousness is. This has led to the theorization of different models of consciousness. Starting from Baars' Global Workspace Theory, this paper examines the models of cognitive architectures that are inspired by it and that can represent a reference point in the field of robot consciousness. Recent Findings Global Workspace Theory has recently been ranked as the most promising theory in its field. However, this is not reflected in the mathematical models of cognitive architectures inspired by it: they are few, and most of them are a decade old, which is too long compared to the speed at which artificial intelligence techniques are improving. Indeed, recent publications propose simple mathematical models that are well designed for computer implementation. Summary In this paper, we introduce an overview of consciousness and robot consciousness, with some interesting insights from the literature. Then we focus on Baars' Global Workspace Theory, presenting it briefly. Finally, we report on the most interesting and promising models of cognitive architectures that implement it, describing their peculiarities

    Prim-based Support-Graph Preconditioners for Min-Cost Flow Problems

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    Support-graph preconditioners have been shown to be a valuable tool for the iterative solution, via a Preconditioned Conjugate Gradient method, of the KKT systems that must be solved at each iteration of an Interior Point algorithm for the solution of Min Cost Flow problems. These preconditioners extract a proper triangulated subgraph, with ``large'' weight, of the original graph: in practice, trees and Brother-Connected Trees (BCTs) of depth two have been shown to be the most computationally efficient families of subgraphs. In the literature, approximate versions of the Kruskal algorithm for maximum-weight spanning trees have most often been used for choosing the subgraphs; Prim-based approaches have been used for trees, but no comparison have ever been reported. We propose Prim-based heuristics for BCTs, which require nontrivial modifications w.r.t. the previously proposed Kruskal-based approaches, and present a computational comparison of the different approaches, which shows that Prim-based heuristics are most often preferable to Kruskal-based ones

    Trajectory and global attractors for generalized processes

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    In this work the theory of generalized processes is used to describe the dynamics of a nonautonomous multivalued problem and, through this approach, some conditions for the existence of trajectory attractors are proved. By projecting the trajectory attractor on the phase space, the uniform attractor for the multivalued process associated to the problem is obtained and some conditions to guarantee the invariance of the uniform attractor are given. Furthermore, the existence of the uniform attractor for a class of p-Laplacian nonautonomous problems with dynamical boundary conditions is established.Conselho Nacional de Desenvolvimento Científico e Tecnológico. BrasilEuropean Commission (EC). Fondo Europeo de Desarrollo Regional (FEDER)Ministerio de Economía y Competitividad (MINECO). EspañaJunta de Andalucí

    Stand-alone wearable system for ubiquitous real-time monitoring of muscle activation potentials

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    Wearable technology is attracting most attention in healthcare for the acquisition of physiological signals. We propose a stand-alone wearable surface ElectroMyoGraphy (sEMG) system for monitoring the muscle activity in real time. With respect to other wearable sEMG devices, the proposed system includes circuits for detecting the muscle activation potentials and it embeds the complete real-time data processing, without using any external device. The system is optimized with respect to power consumption, with a measured battery life that allows for monitoring the activity during the day. Thanks to its compactness and energy autonomy, it can be used outdoor and it provides a pathway to valuable diagnostic data sets for patients during their own day-life. Our system has performances that are comparable to state-of-art wired equipment in the detection of muscle contractions with the advantage of being wearable, compact, and ubiquitous

    Start-up/Shut-down MINLP Formulations for the Unit Commitment with Ramp Constraints

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    In [1 the first MIP exact formulation was provided that describes the convex hull of the solutions satisfying all the standard operational constraints for the thermal units: minimum up- and down-time, minimum and maximum power output, ramp (including start-up and shut-down) limits, general history-dependent start-up costs, and nonlinear convex power production costs. That formulation contains a polynomial, but large, number of variables and constraints. We present two new formulations with fewer variables defined on the shut-down period and computationally test the trade-off between reduced size and possibly weaker bounds. [1] Bacci,T.,Frangioni,A.,Gentile,C.,Tavlaridis-Gyparakis,K.:NewMINLPformulationsfor the single-unit commitment problems with ramping constraints. http://www.optimization- online.org/DB HTML/2019/10/7426.html, submitted (2019
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