884 research outputs found

    Scheduling data flow program in xkaapi: A new affinity based Algorithm for Heterogeneous Architectures

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    Efficient implementations of parallel applications on heterogeneous hybrid architectures require a careful balance between computations and communications with accelerator devices. Even if most of the communication time can be overlapped by computations, it is essential to reduce the total volume of communicated data. The literature therefore abounds with ad-hoc methods to reach that balance, but that are architecture and application dependent. We propose here a generic mechanism to automatically optimize the scheduling between CPUs and GPUs, and compare two strategies within this mechanism: the classical Heterogeneous Earliest Finish Time (HEFT) algorithm and our new, parametrized, Distributed Affinity Dual Approximation algorithm (DADA), which consists in grouping the tasks by affinity before running a fast dual approximation. We ran experiments on a heterogeneous parallel machine with six CPU cores and eight NVIDIA Fermi GPUs. Three standard dense linear algebra kernels from the PLASMA library have been ported on top of the Xkaapi runtime. We report their performances. It results that HEFT and DADA perform well for various experimental conditions, but that DADA performs better for larger systems and number of GPUs, and, in most cases, generates much lower data transfers than HEFT to achieve the same performance

    REM sleep deprivation promotes a dopaminergic influence in the striatal MT2 anxiolytic-like effects

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    AbstractThe aim of this study was to investigate the possible anxiolytic-like effects of striatal MT2 activation, and its counteraction induced by the selective blockade of this receptor. Furthermore, we analyzed this condition under the paradigm of rapid eye movement (REM) sleep deprivation (REMSD) and the animal model of Parkinson’s disease (PD) induced by rotenone. Male Wistar rats were infused with intranigral rotenone (12μg/μL), and 7 days later were subjected to 24h of REMSD. Afterwards the rats underwent striatal micro-infusions of selective melatonin MT2 receptor agonist, 8-M-PDOT (10μg/μL) or selective melatonin MT2 receptor antagonist, 4-P-PDOT (5μg/μL) or vehicle. Subsequently, the animals were tested in the open-field (OP) and elevated plus maze (EPM) tests. Results indicated that the activation of MT2 receptors produced anxiolytic-like effects. In opposite, the MT2 blockade did not show an anxiogenic-like effect. Besides, REMSD induced anxiolytic-like effects similar to 8-M-PDOT. MT2 activation generated a prevalent locomotor increase compared to MT2 blockade in the context of REMSD. Together, these results suggest a striatal MT2 modulation associated to the REMSD-induced dopaminergic supersensitivity causing a possible dopaminergic influence in the MT2 anxiolytic-like effects in the intranigral rotenone model of PD

    Use of Cellulosic Materials as Dye Adsorbents — A Prospective Study

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    Cellulose is the most abundant biopolymer of nature, and it is widely used in the synthesis of new materials as well as in the adsorption of dye. This study reports a literature review (articles) and technology review (patents) about publications and product invention, which contain information on the use of cellulose on the adsorption of dyes in the period 2004–2014. For this work, research database and keywords were used to find articles and patents related to the subject under review. Specific words were used to find articles and patents related to the subject under review. After a demanding research, 1 patent and 23 articles that contain the words “cellulose,” “dye,” and “adsorption or sorption” in their titles were assessed, and annual evolution studies were performed for publications and countries that publish more

    One Dimensional Chain with Long Range Hopping

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    The one-dimensional (1D) tight binding model with random nearest neighbor hopping is known to have a singularity of the density of states and of the localization length at the band center. We study numerically the effects of random long range (power-law) hopping with an ensemble averaged magnitude \expectation{|t_{ij}|} \propto |i-j|^{-\sigma} in the 1D chain, while maintaining the particle-hole symmetry present in the nearest neighbor model. We find, in agreement with results of position space renormalization group techniques applied to the random XY spin chain with power-law interactions, that there is a change of behavior when the power-law exponent σ\sigma becomes smaller than 2

    Ictiofauna Dos Enclaves De Floresta úmida Nos Planaltos Da Ibiapaba E Do Araripe, Nordeste Do Brasil

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Humid highland forest enclaves are remnants of Atlantic Forest found in tablelands within the Caatinga biome (Northeastern Brazil), which emerged during interglacial periods in the Pleistocene. These ecosystems have a highly diverse and endemic fish fauna. Most earlier surveys have focused on the tableland of Borborema (Pernambuco and Paraíba States). In this study we surveyed the fish fauna of the humid forest enclaves in the tablelands of Ibiapaba and Araripe, based on samples collected in the rainy season (March and April) between 2009 and 2014. The 45 sampling points covered rivers, streams and reservoirs in five river basins belonging to three ecoregions. The species were listed according to drainage divide, and endemism was determined for each ecoregion and for the Caatinga. Our area was more species-rich (n=59) than Borborema (n=27). The samples included five introduced species and 29 species endemic to the Caatinga (49.1% of the sampled species). The distribution of Parotocinclus haroldoi was expanded to the Mid-Northeastern Caatinga ecoregion (Timonha river basin, Ceará State). Our study intends to make a significant contribution to current knowledge of the ichthyofauna in humid highland forest enclaves of semiarid Northeastern Brazil, identified as a priority in the conservation of the biodiversity in the Caatinga. © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.164457463/2012-0, CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico552009/2011-3, CNPq, Conselho Nacional de Desenvolvimento Científico e Tecnológico552086/2011-8, CNPq, Conselho Nacional de Desenvolvimento Científico e TecnológicoConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

    Axial sampling height outperforms site as predictor of wood trait variation

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    Covariation amongst wood traits along the stem axis is important to maintain hydraulic integrity ensuring sufficient sap flow to the canopy. Here, we test how wood traits (co)vary along the trunk and whether two seasonally dry Brazilian habitats (cerrado and caatinga) influence this variation in two co-occurring species, Tocoyena formosa (Rubiaceae) and Tabebuia aurea (Bignoniaceae). The samples were collected at five heights along the main trunk of three individuals per species in both sites. We used light, scanning and transmission electron microscopy to observe the wood traits. Out of 13 wood traits, nine show relationships with sampling height: eight traits predict height in T. formosa and five in T. aurea. Contrastingly, only three traits show differences between sites and only for T. formosa. The intratrunk wood variation is reflected by the hydraulically weighted vessel diameter showing a curvilinear relationship, disagreeing with the prediction of a continuous vessel widening from tip to base. In both species, the largest vessels are linked to the thinnest intervessel pit membranes. Wood density increases basipetally for both species, being site-dependent and correlated with vessel traits in T. formosa, and site-independent and determined by fiber wall thickness in T. aurea. Furthermore, the functional role of rays was found to be different for each species, and may be related to the marked difference in ray composition. In conclusion, both species show a unique adaptation to deal with height-related constraints using species-specific co-variation amongst wood traits, while site does not contribute much to the wood variation.Plant science

    Self-avoiding walks and connective constants in small-world networks

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    Long-distance characteristics of small-world networks have been studied by means of self-avoiding walks (SAW's). We consider networks generated by rewiring links in one- and two-dimensional regular lattices. The number of SAW's unu_n was obtained from numerical simulations as a function of the number of steps nn on the considered networks. The so-called connective constant, μ=limnun/un1\mu = \lim_{n \to \infty} u_n/u_{n-1}, which characterizes the long-distance behavior of the walks, increases continuously with disorder strength (or rewiring probability, pp). For small pp, one has a linear relation μ=μ0+ap\mu = \mu_0 + a p, μ0\mu_0 and aa being constants dependent on the underlying lattice. Close to p=1p = 1 one finds the behavior expected for random graphs. An analytical approach is given to account for the results derived from numerical simulations. Both methods yield results agreeing with each other for small pp, and differ for pp close to 1, because of the different connectivity distributions resulting in both cases.Comment: 7 pages, 5 figure

    Tourniquet use for civilian extremity hemorrhage: Systematic review of the literature [Uso de torniquete nas hemorragias de extremidades na população civil: Revisão sistemática da literatura]

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    Introduction: extremity tourniquet (TQ) use has increased in the civilian setting; the beneficial results observed in the military has influenced acceptance by EMS and bystanders. This review aimed to analyze extremity TQ types used in the civilian setting, injury site, indications, and complications. Methods: a systematic review was conducted based on original articles published in PubMed, Embase, and Cochrane following PRISMA guidelines from 2010 to 2019. Data extraction focused on extremity TQ use for hemorrhage control in the civilian setting, demographic data, study type and duration, mechanism of injury, indications for use, injury site, TQ type, TQ time, and complications. Results: of the 1384 articles identified, 14 were selected for review with a total of 3912 civilian victims with extremity hemorrhage and 3522 extremity TQ placements analyzed. The majority of TQs were applied to male (79%) patients, with blunt or penetrating trauma. Among the indications for TQ use were hemorrhagic shock, suspicion of vascular injuries, continued bleeding, and partial or complete traumatic amputations. Upper extremity application was the most common TQ application site (56%), nearly all applied to a single extremity (99%), and only 0, 6% required both upper and lower extremity applications. 80% of the applied TQs were commercial devices, and 20% improvised. Conclusions: TQ use in the civilian setting is associated with trauma-related injuries. Most are single-site TQs applied for the most part to male adults with upper extremity injury. Commercial TQs are more commonly employed, time in an urban setting is under 1 hour, with few complications described. Introdução: o uso de torniquete em extremidades (TQ) aumentou no ambiente civil; os resultados benéficos observados nas forças armadas influenciaram a aceitação por equipes de pré-hospitalar (PH) assim como pela população leiga. Esta revisão teve como objetivo analisar os tipos de TQ de extremidades usados em ambiente civil, local da lesão, indicações e complicações. Métodos: revisão sistemática foi conduzida com base em artigos originais publicados no PubMed, Embase e Cochrane seguindo as diretrizes do PRISMA de 2010 a 2019. Extração de dados focada no uso de TQ de extremidade para controle de hemorragia em ambiente civil, dados demográficos, tipo de estudo e duração, mecanismo de lesão, indicações de uso, local da lesão, tipo de TQ, tempo de TQ e complicações. Resultados: dos 1.384 artigos identificados, 14 foram selecionados para revisão com total de 3.912 vítimas civis com hemorragia nas extremidades e 3.522 colocações de extremidades TQ analisadas. A maioria foi aplicado em pacientes do sexo masculino (79%), com trauma contuso ou penetrante. Entre as indicações estavam choque hemorrágico, suspeita de lesões vasculares, sangramento contínuo e amputações traumáticas parciais ou completas. A aplicação na extremidade superior foi o local de aplicação mais comum (56%), quase todos aplicados a uma única extremidade (99%), e apenas 0, 6% requereram aplicações nas extremidades superior e inferior. 80% dos TQs aplicados eram dispositivos comerciais e 20% improvisados. Conclusões: o uso de TQ em ambientes civis está associado a traumas. Os TQs comerciais são mais utilizados, com tempo menor que uma hora de uso e poucas complicações

    Adsorption of Reactive Particles on a Random Catalytic Chain: An Exact Solution

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    We study equilibrium properties of a catalytically-activated annihilation A+A0A + A \to 0 reaction taking place on a one-dimensional chain of length NN (NN \to \infty) in which some segments (placed at random, with mean concentration pp) possess special, catalytic properties. Annihilation reaction takes place, as soon as any two AA particles land onto two vacant sites at the extremities of the catalytic segment, or when any AA particle lands onto a vacant site on a catalytic segment while the site at the other extremity of this segment is already occupied by another AA particle. Non-catalytic segments are inert with respect to reaction and here two adsorbed AA particles harmlessly coexist. For both "annealed" and "quenched" disorder in placement of the catalytic segments, we calculate exactly the disorder-average pressure per site. Explicit asymptotic formulae for the particle mean density and the compressibility are also presented.Comment: AMSTeX, 27 pages + 4 figure

    Schistosomiasis Mansoni In Urban Northeast Brazil: Influence Of Rainfall Regime On The Population Dynamics Of Biomphalaria Sp

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    Introduction: Our objective was to evaluate the infl uence of rainfall regime on the population dynamics of Biomphalaria in a potential urban focus of schistosomiasis in Aracaju, Brazil, during 2009-2010. Methods: Snails were collected monthly and were counted, measured and identifi ed; the level of infection and fecal contamination at the sampling sites was determined; rainfall data were obtained. Results: High levels of fecal contamination were observed, and the abundance of Biomphalaria glabrata increased during the rainy and post-rainy seasons. The snails' size was variable, and infected snails were identifi ed independently of rainfall. Conclusions: These results provide evidence of anthropogenic and climate interference in an urban focus of schistosomiasis in the Aracaju metropolitan area.465654657Pordeus, L.C., Aguiar, L.R., Quinino, L.R.M., Barbosa, C.S.A., Ocorrência das formas aguda e crônica da esquistossomose mansônica no Brasil no período de 1997 a 2006: Uma revisão de literatura (2008) Epidemiol Serv Saude, 17, pp. 163-175Souza, M.A.A., Barbosa, V.S., Wanderlei, T.N.G., Barbosa, C.S., Criadouros de Biomphalaria, temporários e permanentes, em Jaboatão dos Guararapes, PE (2008) Rev Soc Bras Med Trop, 41, pp. 252-256Araújo, K.C.G.M., Resendes, A.P.C., Souza-Santos, R., Silveira Jr., J.C., Barbosa, C.S., Análise espacial dos focos de Biomphalaria glabrata (Say, 1818) e de casos humanos de esquistossomose mansônica em Porto de Galinhas, Pernambuco, Brasil, no ano 2000 (2007) Cad Saude Publica, 23, pp. 409-417Lima, L.C., Família Planorbidae (1995) Tópicos em Malacologia Médica., pp. 90-112. , In: Barbosa FS, editor. Rio de Janeiro: Fundação Oswaldo Cruz(2005) Resolução CONAMA no 357, , http://www.cetesb.sp.gov.br/Agua/praias/res_conama_357_05.pdf, Conselho Nacional do Meio Ambiente (CONAMA). de 17 de março de. [Cited 2011 February 23]. Available fromSouza, M.A.A., Barbosa, V.S., Albuquerque, J.O., Bocanegra, S., Souza-Santos, R., Paredes, H., Aspectos ecológicos e levantamento malacológico para identificação de áreas de risco para transmissão da esquistossomose mansoni no litoral norte de Pernambuco, Brasil (2010) Iheringia Serie Zoológica, 100, pp. 19-24Barbosa, F.S., Barbosa, C.S., The bioecology of snails vectors for schistosomiasis in Brazil (1994) Cad Saude Publica, 10, pp. 200-209Fernandez, M.A., Thiengo, S.C., Susceptibility of Biomphalaria straminea from Peixe Angical dam, Tocantins, Brazil to infection with three strains of Schistosoma mansoni (2010) Mem Inst Oswaldo Cruz, 105, pp. 488-491Barbosa, C.S., Domingues, A.L.C., Abath, F., Montenegro, S.M.L., Guida, U., Carneiro, J., Epidemia de esquistossomose aguda na praia de Porto de Galinhas, Pernambuco, Brasil (2001) Cad Saude Publica, 17, pp. 725-728Rollemberg, C.V.V., Santos, C.M.B., Silva, M.M.B.L., Souza, A.M.B., Silva, A.M., Almeida, J.A.P., Aspectos epidemiológicos e distribuição geográfica da esquistossomose e geo-helmintos, no Estado de Sergipe, de acordo com os dados do Programa de Controle da Esquistossomose (2011) Rev Soc Bras Med Trop, 44, pp. 91-96Barbosa, C.S., Montenegro, S.M.L., Abath, F.G., Domingues, A.L.C., Eventos epidemiológicos relacionados à transmissão da esquistossomose em áreas rurais e urbanas de Pernambuco (2002) Mem Inst Oswaldo Cruz, 96, pp. 169-172Departamento de Vigilância Epidemiológica (2008) Vigilância e controle de moluscos de importância epidemiológica: Diretrizes técnicas., , Ministério da Saúde. Programa de Vigilância e Controle da Esquistossomose (PCE). 2nded. Brasília: Ministério da Saúd
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