1,152 research outputs found

    On Optimal Placements of Processors in Tori Networks

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    Two and three dimensional k-tori are among the most used topologies in the design of new parallel computers. Traditionally (with the exception of the Tera parallel computer), these networks have been used as fully-populated networks, in the sense that every routing node in the topology is subjected to message injection. However, fully-populated tori and meshes exhibit a theoretical throughput which degrades as the network size increases. In addition, the performance of those networks is sensitive to link faults. In contrast, multistage networks (that are partially populated) scale well with the network size. We propose to add slackness in fully-populated tori by reducing the number of processors and we study optimal fault-tolerant routing strategies for the resulting interconnections. The key concept that we study is the average link load in an interconnection network with a given placement and a routing algorithm, where a placement is the subset of the nodes in the interconnection network that are attached to processors. Reducing the load on the links by the choice of a placement and a routing algorithm leads to improvements in both the performance and the fault tolerance of the communication system. Our main contribution is the construction of optimal placements for 2 and 3-dimensional k-tori networks and their corresponding routing algorithms. Those placements yield a linear (in the number of processors) link load and are of optimal size

    AGUILA: an automatic tube detection system

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    This paper discusses a system which uses machine vision algorithms for the detection of tubes in an extremely "noisy" industrial environment . The heart of the algorithm consists of sampling of the image in predefined sparse bands perpendicular to the likely orientation of the tubes followed by the application of a normalized correlation as a detection filter over these bands. After assigning a reliability factor to each local maxima of the correlation function, these points are then mapped to the Hough space to determine the equations of the midlines of the tubes. Given these equations, the number of tubes, and any positional anomalies are reported.Facultad de Ingenierí

    Gregariousness in the giant sloth Lestodon (Xenarthra): multi-proxy approach of a bonebed from the Last Maximum Glacial of Argentine Pampas

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    Megamammals constituted an important component in the Pleistocene faunal communities of South America. Paleobiological and paleoecological studies involving different megamammal taxa have increased significantly in the last years, but there are still several poorly-known issues of its life history. In this work, we analyze an assemblage composed of 13 individuals of different ontogenetic stages, and possibly different sex, belonging to the giant ground sloth Lestodon armatus (Xenarthra, Folivora), recovered from Playa del Barco site (Pampean Region, Argentina). A dating of 19,849 years Cal BP allows assigning this assemblage to a period of the MIS (Marine Isotope Stage) 2 related to the end of the Last Glacial Maximum. Based on multiple lines of research (e.g. taphonomy, paleopathology, osteohistology, isotopy), we interpret the origin of the assemblage and diverse paleobiological and paleoecological aspects (e.g. social behavior, ontogenetic changes, sexual dimorphism, diseases, resource and habitat use, trophic relationships) of L. armatus. Evidence suggests that the assemblage was formed by a local single event of catastrophic mortality, which affected different members of a social group. This record represents the first accurate evidence of gregariousness for this ground sloth, providing new data on a poorly-known behavior among extinct Folivora

    Emergency hospital services utilization in Lleida (Spain): A cross-sectional study of immigrant and Spanish-born populations

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    <p>Abstract</p> <p>Background</p> <p>The use of emergency hospital services (EHS) has increased steadily in Spain in the last decade while the number of immigrants has increased dramatically. Studies show that immigrants use EHS differently than native-born individuals, and this work investigates demographics, diagnoses and utilization rates of EHS in Lleida (Spain).</p> <p>Methods</p> <p>Cross-sectional study of all the 96,916 EHS visits by patients 15 to 64 years old, attended during the years 2004 and 2005 in a public teaching hospital. Demographic data, diagnoses of the EHS visits, frequency of hospital admissions, mortality and diagnoses at hospital discharge were obtained. Utilization rates were estimated by group of origin. Poisson regression was used to estimate the rate ratios of being visited in the EHS with respect to the Spanish-born population.</p> <p>Results</p> <p>Immigrants from low-income countries use EHS services more than the Spanish-born population. Differences in utilization patterns are particularly marked for Maghrebi men and women and sub-Saharan women. Immigrant males are at lower risk of being admitted to the hospital, as compared with Spanish-born males. On the other hand, immigrant women are at higher risk of being admitted. After excluding the visits with gynecologic and obstetric diagnoses, women from sub-Saharan Africa and the Maghreb are still at a higher risk of being admitted than their Spanish-born counterparts.</p> <p>Conclusion</p> <p>In Lleida (Spain), immigrants use more EHS than the Spanish born population. Future research should indicate whether the same pattern is found in other areas of Spain and whether EHS use is attributable to health needs, barriers to access to the primary care services or similarities in the way immigrants access health care in their countries of origin.</p

    Next Generation Flow for highly sensitive and standardized detection of minimal residual disease in multiple myeloma

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    [EN]Flow cytometry has become a highly valuable method to monitor minimal residual disease (MRD) and evaluate the depth of complete response (CR) in bone marrow (BM) of multiple myeloma (MM) after therapy. However, current flow-MRD has lower sensitivity than molecular methods and lacks standardization. Here we report on a novel next generation flow (NGF) approach for highly sensitive and standardized MRD detection in MM. An optimized 2-tube 8-color antibody panel was constructed in five cycles of design-evaluation-redesign. In addition, a bulk-lysis procedure was established for acquisition of ⩾107 cells/sample, and novel software tools were constructed for automatic plasma cell gating. Multicenter evaluation of 110 follow-up BM from MM patients in very good partial response (VGPR) or CR showed a higher sensitivity for NGF-MRD vs conventional 8-color flow-MRD -MRD-positive rate of 47 vs 34% (P=0.003)-. Thus, 25% of patients classified as MRD-negative by conventional 8-color flow were MRD-positive by NGF, translating into a significantly longer progression-free survival for MRD-negative vs MRD-positive CR patients by NGF (75% progression-free survival not reached vs 7 months; P=0.02). This study establishes EuroFlow-based NGF as a highly sensitive, fully standardized approach for MRD detection in MM which overcomes the major limitations of conventional flow-MRD methods and is ready for implementation in routine diagnostics.This work has been supported by the International Myeloma Foundation-Black Swan Research Initiative, the Red Temática de Investigación Cooperativa en Cáncer (RTICC); grant SA079U14 from the Consejería de Educación, Junta de Castilla y León, Valladolid, Spain and; grant DTS15/00119 from Instituto de Salud Carlos III, Ministerio de Economía y Competitividad, Madrid, Spain

    G-arylated hydrogen-bonded cyclic tetramer assemblies with remarkable thermodynamic and kinetic stability

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    The preparation and self-assembly of novel G-C dinucleoside monomers that are equipped with electron-poor aryl groups at the G-N2 amino group have been studied. Such monomers associate via Watson-Crick H-bonding into discrete unstrained tetrameric macrocycles that arise as a thermodynamically and kinetically stabilized product in a wide variety of experimental conditions, including very polar solvent environments and low concentrations. G-arylation produces an increased stability of the cyclic assembly, as a result of a subtle interplay between enthalpic and entropic effects involving the solvent coordination sphereFunding from the European Research Council (ERC-StG 279548) and MINECO (CTQ2011-23659) is gratefully acknowledge

    Characterization of Italian honeys (Marche Region) on the basis of their mineral content and some typical quality parameters

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    <p>Abstract</p> <p>Background</p> <p>The characterization of three types of Marche (Italy) honeys (Acacia, Multifloral, Honeydew) was carried out on the basis of the their quality parameters (pH, sugar content, humidity) and mineral content (Na, K, Ca, Mg, Cu, Fe, and Mn). Pattern recognition methods such as principal components analysis (PCA) and linear discriminant analysis (LDA) were performed in order to classify honey samples whose botanical origins were different, and identify the most discriminant parameters. Lastly, using ANOVA and correlations for all parameters, significant differences between diverse types of honey were examined.</p> <p>Results</p> <p>Most of the samples' water content showed good maturity (98%) whilst pH values were in the range 3.50 – 4.21 confirming the good quality of the honeys analysed. Potassium was quantitatively the most relevant mineral (mean = 643 ppm), accounting for 79% of the total mineral content. The Ca, Na and Mg contents account for 14, 3 and 3% of the total mineral content respectively, while other minerals (Cu, Mn, Fe) were present at very low levels. PCA explained 75% or more of the variance with the first two PC variables. The variables with higher discrimination power according to the multivariate statistical procedure were Mg and pH. On the other hand, all samples of acacia and honeydew, and more than 90% of samples of multifloral type have been correctly classified using the LDA. ANOVA shows significant differences between diverse floral origins for all variables except sugar, moisture and Fe.</p> <p>Conclusion</p> <p>In general, the analytical results obtained for the Marche honeys indicate the products' high quality. The determination of physicochemical parameters and mineral content in combination with modern statistical techniques can be a useful tool for honey classification.</p
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