938 resultados para Super-Peers
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We extend the construction and analysis of the non-overlapping Schwarz preconditioners proposed in Antonietti et al. [Math. Model. Numer. Anal., 41(1):21-54, 2007] and [Math. Model. Numer. Anal., submitted, 2006] to the (non-consistent) super penalty discontinuos Galerkin methods introduced by Babuska et al. [SIAM J. Numer. Anal., 10:863-875, 1973] and by Brezzi et al. [Numer. Methods Partial Differential Equations, 16(4):365-378, 2000]. We show that the resulting preconditioners are scalable, and we provide the convergence estimates. We also present numerical experiments demonstrating the theoretical results.
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Since primary school pupils lack a common language, primary school pupils from Germany and Africa show a piece of their origin and of their daily live through simple drawings to their peers in a other, distant land. The teachers accompanying the exchange of these drawings communicated in natural language, but helped to transform what their pupils wanted to show by their drawing. Five students drawings are presented in order to explain and illustrate this exchange method.
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Context. With about 2000 extrasolar planets confirmed, the results show that planetary systems have a whole range of unexpected properties. This wide diversity provides fundamental clues to the processes of planet formation and evolution. Aims: We present a full investigation of the HD 219828 system, a bright metal-rich star for which a hot Neptune has previously been detected. Methods: We used a set of HARPS, SOPHIE, and ELODIE radial velocities to search for the existence of orbiting companions to HD 219828. The spectra were used to characterise the star and its chemical abundances, as well as to check for spurious, activity induced signals. A dynamical analysis is also performed to study the stability of the system and to constrain the orbital parameters and planet masses. Results: We announce the discovery of a long period (P = 13.1 yr) massive (m sini = 15.1 MJup) companion (HD 219828 c) in a very eccentric orbit (e = 0.81). The same data confirms the existence of a hot Neptune, HD 219828 b, with a minimum mass of 21 M⊕ and a period of 3.83 days. The dynamical analysis shows that the system is stable, and that the equilibrium eccentricity of planet b is close to zero. Conclusions: The HD 219828 system is extreme and unique in several aspects. First, ammong all known exoplanet systems it presents an unusually high mass ratio. We also show that systems like HD 219828, with a hot Neptune and a long-period massive companion are more frequent than similar systems with a hot Jupiter instead. This suggests that the formation of hot Neptunes follows a different path than the formation of their hot jovian counterparts. The high mass, long period, and eccentricity of HD 219828 c also make it a good target for Gaia astrometry as well as a potential target for atmospheric characterisation, using direct imaging or high-resolution spectroscopy. Astrometric observations will allow us to derive its real mass and orbital configuration. If a transit of HD 219828 b is detected, we will be able to fully characterise the system, including the relative orbital inclinations. With a clearly known mass, HD 219828 c may become a benchmark object for the range in between giant planets and brown dwarfs.
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Context. The gamma-ray binary LS I +61º303 is a well-established source from centimeter radio up to very high energy (VHE; E > 100 GeV). The broadband emission shows a periodicity of ∼26.5 days, coincident with the orbital period. A longer (super-orbital) period of 1667 ± 8 days was proposed from radio variability and confirmed using optical and high-energy (HE; E ¿ 100 MeV) gamma-ray observations. In this paper, we report on a four-year campaign performed by MAGIC together with archival data concentrating on a search for a long-timescale signature in the VHE emission from LS I +61º303. Aims. We focus on the search for super-orbital modulation of the VHE emission, similar to that observed at other energies, and on the search for correlations between TeV emission and an optical determination of the extension of the circumstellar disk. Methods. A four-year campaign has been carried out using the MAGIC telescopes. The source was observed during the orbital phases when the periodic VHE outbursts have occurred (φ = 0.55 – 0.75, one orbit = 26.496 days). Additionally, we included archival MAGIC observations and data published by the VERITAS collaboration in these studies. For the correlation studies, LS I +61◦303 has also been observed during the orbital phases where sporadic VHE emission had been detected in the past (φ = 0.75 – 1.0). These MAGIC observations were simultaneous with optical spectroscopy from the LIVERPOOL telescope. Results. The TeV flux of the periodical outburst in orbital phases φ = 0.5 – 0.75 was found to show yearly variability consistent with the long-term modulation of ∼4.5 years found in the radio band. This modulation of the TeV flux can be well described by a sine function with a best-fit period of 1610±58 days. The complete data, including archival observations, span two super-orbital periods. There is no evidence for a correlation between the TeV emission and the mass-loss rate of the Be star, but this may be affected by the strong, short-timescale (as short as intra-day) variation displayed by the Hα fluxes.
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Na indústria têxtil grandes volumes de efluentes são gerados, os quais são caracterizados por serem coloridos e poluentes , devido à presença de corantes em sua composição. Com a necessidade de descontaminação, diferentes métodos são utilizados no tratamento, sendo um deles, a biossorção. Este consiste na remoção das substâncias tóxicas recorrendo a biossorventes obtidos a partir de resíduos agrícolas e sub-produtos de processos industriais. O objetivo principal deste trabalho foi estudar a remoção do corante Preto Reafix Super 2R em soluções aquosas por meio de biossorção com bagaço de malte. Baseando-se sobretudo no estudo da cinética e equilíbrio entre o biossorvente e o corante. Numa primeira fase foi estudada a influência dos parâmetros operacionais, como a influência do diâmetro médio das partículas do biossorvente, o pH da solução e a velocidade de agitação da solução. Sendo as condições ótimas de biossorção definidas a pH 2, velocidade de agitação de 150 rpm e biomassa sem peneiramento. Posteriormente, ajustaram-se os modelos cinéticos de Pseudo-primeira ordem, Pseudo-segunda ordem e de Difusão intrapartícula aos resultados experimentais obtidos pela cinética de adsorção avaliando também a influência da temperatura no tempo de contato para se alcançar o equilibrio. O modelo de Pseudo-segunda ordem conduziu ao melhor ajuste, com um coeficiente de correlação (R2) de apróximadamente 1. A partir dos testes de equilíbrio realizados com diferentes concentrações de corante, foram ajustadas as isotermas de Langmuir, Freundlich, Tempkin aos resultados experimentais tendo-se obtido parâmetros bastante significativos para o modelo Langmuir, cuja capacidade máxima de remoção (qmax) obtida foi de 40,16 mg.g-1. A análise dos parâmetros termodinâmicos permitiram avaliar que o processo de adsorção ocorre espontaneamente, sendo endotérmico e que ao longo do processo aumenta a aleatoriedade na interface sólido/solução, devido à desorganização do processo em virtude das interações que ocorrem.
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The present work submitted as a PhD thesis has the aim of studying from a philological point of view, the Latin text Consolatoria super obitu inclyti principis Hispaniarum Iohannis, written by the Castilian canon Alfonso Ortiz, who lived in the late 15th century in the time of the Catholic Monarchs (Isabel and Fernando), on the death of Prince John, first and only son of the sovereigns. The core of this work is the critical edition (the first complete edition ever made) on the comparison of two extant manuscripts (S and St), the second having the Spanish self-translation of the first. On the basis of this critical text we study the literary references as well as its structure and the literary genre to which it may be ascribed and, besides, we point out some features of the language used therein (Latin), the scope and characteristics of the self-translation and other style and rhetorical topics (e.g. the use of rhythmic clausulae at the end of sentences). Several appendices are added to complete and improve the text-study From that study it may be concluded that although the work follows a long time proven tradition based on medieval religious Ideas, the author, nonetheless, continuously shows within the text that he is willing to adapt that tradition into the new tunes of early Renaissance, not only by means of language and style features, but also through matter nuances that made it clear that life/death concepts were gradually shifting from the medieval times to the ideas of the new epoch. As the value of human life was rising, it needed a more attentive, profound and meticulous consolation through both conceptual and rhetorical arguments...
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Introduction: Staphylococcus aureus is a pathogen that causes food poisoning as well as hospital and community acquired infections. Objective: Establish the profile of superantigen genes among hospital isolates in relation to clinical specimen type, susceptibility to antibiotics and hospital or community acquisition. Methods: Eighty one isolates obtained from patients at Colombian hospital, were classified by antimicrobial susceptibility, specimen type and hospital or community acquired . The PCR uniplex and multiplex was used for detection of 22 superantigen genes (18 enterotoxins, tsst-1 and three exfoliative toxins). Results: Ninety five point one percent of isolates harbored one or more of the genes with an average of 5.6 genes. Prevalence of individual genes was variable and the most prevalent was seg (51.9%). Thirty nine genotypes were obtained, and the genotype gimnou (complete egc cluster) was the most prevalent alone (16.0%) and in association with other genes (13.6%). The correlation between presence of superantigens and clinical specimen or antimicrobial susceptibility showed no significant difference. But there was significant difference between presence of superantigens and the origin of the isolates, hospital or community acquired (p= 0.049). Conclusions: The results show the variability of the superantigen genes profile in hospital isolates and shows no conclusive relationship with the clinical sample type and antimicrobial susceptibility, but there was correlation with community and hospital isolates. The analysis of the interplay between virulence, epidemic and antibiotic resistance of bacterial populations is needed to predict the future of infectious diseases.
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Pie de imp. tomado del colofón