2,841 research outputs found
The Dynamic Phase Transition for Decoding Algorithms
The state-of-the-art error correcting codes are based on large random
constructions (random graphs, random permutations, ...) and are decoded by
linear-time iterative algorithms. Because of these features, they are
remarkable examples of diluted mean-field spin glasses, both from the static
and from the dynamic points of view. We analyze the behavior of decoding
algorithms using the mapping onto statistical-physics models. This allows to
understand the intrinsic (i.e. algorithm independent) features of this
behavior.Comment: 40 pages, 29 eps figure
AoI-based Multicast Routing over Voronoi Overlays with Minimal Overhead
The increasing pervasive and ubiquitous presence of devices at the edge of
the Internet is creating new scenarios for the emergence of novel services and
applications. This is particularly true for location- and context-aware
services. These services call for new decentralized, self-organizing
communication schemes that are able to face issues related to demanding
resource consumption constraints, while ensuring efficient locality-based
information dissemination and querying. Voronoi-based communication techniques
are among the most widely used solutions in this field. However, when used for
forwarding messages inside closed areas of the network (called Areas of
Interest, AoIs), these solutions generally require a significant overhead in
terms of redundant and/or unnecessary communications. This fact negatively
impacts both the devices' resource consumption levels, as well as the network
bandwidth usage. In order to eliminate all unnecessary communications, in this
paper we present the MABRAVO (Multicast Algorithm for Broadcast and Routing
over AoIs in Voronoi Overlays) protocol suite. MABRAVO allows to forward
information within an AoI in a Voronoi network using only local information,
reaching all the devices in the area, and using the lowest possible number of
messages, i.e., just one message for each node included in the AoI. The paper
presents the mathematical and algorithmic descriptions of MABRAVO, as well as
experimental findings of its performance, showing its ability to reduce
communication costs to the strictly minimum required.Comment: Submitted to: IEEE Access; CodeOcean: DOI:10.24433/CO.1722184.v1;
code: https://github.com/michelealbano/mabrav
AmI Systems as Agent-Based Mirror Worlds: Bridging Humans and Agents through Stigmergy
In this chapter we introduce a vision of agent-oriented AmI systems that is extended to integrate ideas inspired by MirrorWorlds as introduced by Gelernter at the beginning of the eighties. In this view, AmI systems are actually a digital world mirroring but also augmenting the physical world with capabilities, services and functionalities.We then discuss the value of stigmergy as background reference conceptual framework to define and understand interactions occurring between the physical environments and its digital agent-based extension. The digital world augments the physical world so that traces left by humans acting in the physical world are represented in the digital one in order to be perceived by software agents living there and, viceversa, actions taken by software agents in the mirror can have an effect on the connected physical counterpart
Study of the chemical and nutritional characteristics of commercial dog foods used as elimination diet for the diagnosis of canine food allergy
"Hypoallergenic" pet foods are commercial dietary products for dogs and cats used as elimination diets for the diagnosis of adverse food reactions. Aim of this study was to compare chemical and nutritional characteristics of this kind of dog foods with regular maintenance diets. Twenty-nine dry pet foods (pellets) were collected and divided into classes on the basis of the type (H: hypoallergenic; R: regular), source of fat (with or without fish oil) and source of protein (with or without fish protein) used in their composition. Labels of the H pet foods identified 8 products (44%) with one protein in their formula, suggesting that only few commercial manufacturers concern about the number of protein sources included in their products. Samples of the two groups showed different chemical profiles with lower levels of protein, gross energy, phosphorus and better fatty acid profile (expressed as % of total fatty acids) for H products in comparison to R foods: PUFA, 38.91 vs 24.03, P<0.01; Ï3, 5.70 vs 2.58, P<0.01; Ï6, 33.22 vs 21.63, P<0.01; DHA, 2.85 vs 0.16, P<0.05; CLA, 0.24 vs 0.08, P<0.05, for H and R respectively. This study suggests that the differences observed in the fatty acids composition may be attributed to fish proteins addition, but not to fish oil, in H pet foods production
Secondary flow and radial mixing modelling for CFD-based Through-Flow methods: an axial turbine application
Abstract The paper presents the theoretical bases and an application of a CFD-based Through-Flow model. The code solves the axisymmetric Euler equations and takes into account the effect of tangential blockage and body force. It inherits its numerical scheme from a state-of-the-art CFD solver (TRAF code). Blade body forces are calculated directly from the tangency condition to the meridional flow surface, which is iteratively adapted during the time-marching procedure. Dissipative forces are computed through a realistic distribution of entropy along streamlines. Both secondary flow and tip leakage effects on the meridional flow-field are included through the adoption of a concentrated vortex model, while the corresponding loss contributions are evaluated from correlations. Also, a radial mixing model considering both turbulent diffusion and spanwise convection is implemented. The accuracy of the method is assessed by comparison with CFD calculations and experimental data on the transonic CT3 turbine stage tested in the framework of the TATEF2 European project. A good agreement in terms of overall performance and radial distributions is achieved for both design and off-design operating conditions
Embodied Organizations: a Unifying Perspective in Programming Agents, Organizations and Environments
http://ceur-ws.org/Vol-627/coin_7.pdfInternational audienceMAS research pushes the notion of openness related to systems combining heterogeneous computational entities. Typically, those entities answer to different purposes and functions and their integration is a crucial issue. Starting from a comprehensive approach in developing agents, organizations and environments, this paper devises an integrated approach and describes a unifying programming model. It introduces the notion of embodied organization, which is described first focusing on the main entities as separate concerns; and, second, establishing different interaction styles aimed to seamlessly integrate the various entities in a coherent system. An integration framework, built on top of Jason, CArtAgO and Moise (as programming platforms for agents, environments and organizations resp.) is described as a suitable technology to build embodied organizations in practice
Designing Controversies and their Publics
Controversy mapping is a teaching and research method derived from the Science and Technology Studies and meant to explore and represent modern sociotechnical issues. Striving to make the intricacy of scientific debate readable for a larger public, controversy mapping is trapped in a classic simplicity/complexity trade-?âoff: how to respect the richness of controversies without designing maps too complicated to be useful? Having worked on the question for almost two years in a project bringing together social scientists and designers (emapsproject.com1), we can now propose a way out of this contradiction and suggest three ways of moving through the simplicity/complexity continuum. The first movement -?âby multiplying the number of maps and by taking into account users before the beginning and after the end of the design process-?â allows to bypass the simplicity/complexity trade-?âoff. The second movement bind together narration and exploration and allows the publics to venture in the maze of controversies unraveling the story that will guide them out. The third movement allows to involve the publics through all the phases of a cartographic campaign and to engage it again and again
UCN-01 enhances cytotoxicity of irinotecan in colorectal cancer stem-like cells by impairing DNA damage response
Colorectal cancer (CRC) is one of the most common and lethal cancers worldwide. Despite recent progress, the prognosis of advanced stage CRC remains poor, mainly because of cancer recurrence and metastasis. The high morbidity and mortality of CRC has been recently ascribed to a small population of tumor cells that hold the potential of tumor initiation, i.e. cancer stem cells (CSCs), which play a pivotal role in cancer recurrence and metastasis and are not eradicated by current therapy. We screened CRC-SCs in vitro with a library of protein kinase inhibitors and showed that CRC-SCs are resistant to specific inhibition of the major signaling pathways involved in cell survival and proliferation. Nonetheless, broad-spectrum inhibition by the staurosporin derivative UCN-01 blocks CRC-SC growth and potentiates the activity of irinotecan in vitro and in vivo CRC-SC-derived models. Reverse-Phase Protein Microarrays (RPPA) revealed that, albeit CRC-SCs display individual phospho-proteomic profiles, sensitivity of CRC-SCs to UCN-01 relies on the interference with the DNA damage response mediated by Chk1. Combination of LY2603618, a specific Chk1/2 inhibitor, with irinotecan resulted in a significant reduction of CRC-SC growth in vivo, confirming that irinotecan treatment coupled to inhibition of Chk1 represents a potentially effective therapeutic approach for CRC treatment
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