80 research outputs found

    An infinite family of magnetized Morgan-Morgan relativistic thin disks

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    Applying the Horsk\'y-Mitskievitch conjecture to the empty space solutions of Morgan and Morgan due to the gravitational field of a finite disk, we have obtained the corresponding solutions of the Einstein-Maxwell equations. The resulting expressions are simply written in terms of oblate spheroidal coordinates and the solutions represent fields due to magnetized static thin disk of finite extension. Now, although the solutions are not asymptotically flat, the masses of the disks are finite and the energy-momentum tensor agrees with the energy conditions. Furthermore, the magnetic field and the circular velocity show an acceptable physical behavior.Comment: Submitted to IJTP. This paper is a revised and extended version of a paper that was presented at arXiv:1006.203

    Phenotypic, additive genetic and environment correlations of maize landraces populations in family farm systems

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    Knowledge of the association between characters is very important in the genetic breeding programs, but there is limited information about correlations between traits in maize landraces in the current literature. The objectives of this study were to estimate phenotypic, additive genetic and environment correlations among traits in maize landraces, which were cultivated in family farm systems, in order to guide the participatory breeding on maize landraces. Between 294 and 400 half-sib progenies from the six populations were evaluated, subdivided in triple 7X7 and 10X10 lattice design, respectively, with single row plots of 4 m long and spaced 1.00 × 0.20 m. Estimates of correlation coefficients are reported for nine traits: grain yield (GY), relation grain weight per ear weight (GE), ears per plant (EP), days to flower (DF), plant height (PH), ear height (EH), percentage of root loding (%L), percentage of stalk loding (%BS) and percentage of damaged ears (%DE). A high number of additive genetic correlation (rA) was obtained between grain yield and the other traits, in maize landraces populations, cycles and locations. For grain yield, the highest averages of the rA estimate were with EP (0.67), GE (0.47) and %DE (-0.63). In contrast to the current published researches, negative correlations between grain yield and days to flower were observed.O conhecimento da associação entre caracteres é de grande importância nos programas de melhoramento genético, contudo a literatura apresenta limitadas informações sobre correlações em populações de milho crioulo. Os objetivos deste estudo foram estimar correlações fenotípicas, genéticas aditivas e ambientais entre caracteres de populações de milho crioulo, cultivados em sistemas de agricultura familiar, para orientar o programa de melhoramento genético participativo. Entre 294 e 400 de progênies de meios-irmãos de seis populações, foram avaliadas em látices triplos 7X7 e 10X10, respectivamente, com parcelas de 4 m de comprimento e espaçadas 1,00 × 0,20 m. Os coeficientes de correlações foram estimados para nove características: produtividade de grãos total (GY), relação peso de grãos por peso de espiga (GE), nº de espigas por planta (EP), nº de dias do florescimento (DF), altura da planta (PH), altura espiga (EH), porcentagem de acamamento (%L), porcentagem de colmos quebrados (%BS) e porcentagem de espigas danificadas (%DE). Houve um alto número de correlação genética aditiva (rA) entre produtividade de grãos e as demais características, nas populações de milho crioulo, ciclos e locais. As maiores médias das estimativas rA para o produtividade de grãos foram com EP (0,67), GE (0,47) e DE% (-0,63). Diferentemente dos trabalhos publicados, foram observadas correlações negativas entre produtividade de grãos e dias para florescimento

    Cholini (Coleoptera: Curculionidae, Molytinae) depositados na Coleção de Invertebrados do Instituto Nacional de Pesquisas da Amazônia

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    In Brazilian Amazonia, Cholini (Coleoptera, Curculionidae, Molytinae) is represented by 53 species distributed in seven generaAmeris Dejean, 1821; Cholus Germar, 1824; Homalinotus Sahlberg, 1823; Lobaspis Chevrolat, 1881; Odontoderes Sahlberg, 1823; Ozopherus Pascoe, 1872 and Rhinastus Schoenherr, 1825. This work documents the species of Cholini housed in the Invertebrate Collection of the Instituto Nacional de Pesquisas da Amazônia, Manaus, Brazil and gives the geographical and biological data associated with them. A total of 186 Cholini specimens were identified as belonging to 14 species (13 from Brazilian Amazonia) and five genera (Cholus, Homalinotus, Odontoderes, Ozopherus and Rhinastus). Only 24% of the Cholini species reported from Brazilian Amazonia are actually represented in the INPA collection, underscoring the need for a more systematical collecting based on available biological information. The known geographical distribution was expanded for the following speciesCholus granifer (Chevrolat, 1881) for Brazil; C. pantherinus (Olivier, 1790) for Manaus (Amazonas); Cholus parallelogrammus (Germar, 1824) for Piraquara (Paraná); Homalinotus depressus (Linnaeus, 1758) for lago Janauacá (Amazonas) and rio Tocantins (Pará); H. humeralis (Gyllenhal, 1836) for Novo Airão, Coari (Amazonas) and Porto Velho (Rondônia); H. nodipennis (Chevrolat, 1878) for Carauari, Lábrea (Amazonas) and Ariquemes (Rondônia); H. validus (Olivier, 1790) for rio Araguaia (Brasil), Manaus (Amazonas), rio Tocantins (Pará), Porto Velho and BR 364, Km 130 (Rondônia); Odontoderes carinatus (Guérin-Méneville, 1844) for Manaus (Amazonas); O. spinicollis (Boheman, 1836) for rio Uraricoera (Roraima); and Ozopherus muricatus Pascoe, 1872 for lago Janauacá (Amazonas). Homalinotus humeralis is reported for the first time from "urucuri" palm, Attalea phalerata Mart. ex Spreng.Na Amazônia brasileira, Cholini (Coleoptera, Curculionidae, Molytinae) é representada por 53 espécies, distribuídas em sete gêneros: Ameris Dejean, 1821; Cholus Germar, 1824; Homalinotus Sahlberg, 1823; Lobaspis Chevrolat, 1881; Odontoderes Sahlberg, 1823; Ozopherus Pascoe, 1872 e Rhinastus Schoenherr, 1825. Este trabalho documenta as espécies de Cholini depositadas na Coleção de Invertebrados do Instituto Nacional de Pesquisas da Amazônia, Manaus, Brasil, além de apresentar a distribuição geográfica e informações sobre a biologia dessas espécies. Foram identificados 186 espécimes de Cholini, pertencentes a 14 espécies (13 da Amazônia brasileira) e cinco gêneros (Cholus, Homalinotus, Odontoderes, Ozopherus e Rhinastus). Somente 24% das espécies de Cholini registradas para a Amazônia brasileira estão representadas na coleção do INPA, ressaltando a necessidade de um esforço de coleta sistemático baseado na informação biológica disponível. Foi ampliada a distribuição geográfica conhecida das seguintes espécies: Cholus granifer (Chevrolat, 1881) para Brasil; C. pantherinus (Olivier, 1790) para Manaus (Amazonas); Cholus parallelogrammus (Germar, 1824) para Piraquara (Paraná); Homalinotus depressus (Linnaeus, 1758) para lago Janauacá (Amazonas) e rio Tocantins (Pará); H. humeralis (Gyllenhal, 1836) para Novo Airão, Coari (Amazonas) e Porto Velho (Rondônia); H. nodipennis (Chevrolat, 1878) para Carauari, Lábrea (Amazonas) e Ariquemes (Rondônia); H. validus (Olivier, 1790) para rio Araguaia (Brasil), Manaus (Amazonas), rio Tocantins (Pará), Porto Velho e BR 364, Km 130 (Rondônia); Odontoderes carinatus (Guérin-Méneville, 1844) para Manaus (Amazonas); O. spinicollis (Boheman, 1836) para rio Uraricoera (Roraima) e Ozopherus muricatus Pascoe, 1872 para lago Janauacá (Amazonas). Homalinotus humeralis é associado pela primeira vez com a palmeira urucuri Attalea phalerata Mart. ex Spreng

    Track D Social Science, Human Rights and Political Science

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    Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138414/1/jia218442.pd

    Measurement of the azimuthal anisotropy of Y(1S) and Y(2S) mesons in PbPb collisions at √S^{S}NN = 5.02 TeV

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    The second-order Fourier coefficients (υ2_{2}) characterizing the azimuthal distributions of Υ(1S) and Υ(2S) mesons produced in PbPb collisions at sNN\sqrt{s_{NN}} = 5.02 TeV are studied. The Υmesons are reconstructed in their dimuon decay channel, as measured by the CMS detector. The collected data set corresponds to an integrated luminosity of 1.7 nb1^{-1}. The scalar product method is used to extract the υ2_{2} coefficients of the azimuthal distributions. Results are reported for the rapidity range |y| < 2.4, in the transverse momentum interval 0 < pT_{T} < 50 GeV/c, and in three centrality ranges of 10–30%, 30–50% and 50–90%. In contrast to the J/ψ mesons, the measured υ2_{2} values for the Υ mesons are found to be consistent with zero

    Performance of the CMS Level-1 trigger in proton-proton collisions at √s = 13 TeV

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    At the start of Run 2 in 2015, the LHC delivered proton-proton collisions at a center-of-mass energy of 13\TeV. During Run 2 (years 2015–2018) the LHC eventually reached a luminosity of 2.1× 1034^{34} cm2^{-2}s1^{-1}, almost three times that reached during Run 1 (2009–2013) and a factor of two larger than the LHC design value, leading to events with up to a mean of about 50 simultaneous inelastic proton-proton collisions per bunch crossing (pileup). The CMS Level-1 trigger was upgraded prior to 2016 to improve the selection of physics events in the challenging conditions posed by the second run of the LHC. This paper describes the performance of the CMS Level-1 trigger upgrade during the data taking period of 2016–2018. The upgraded trigger implements pattern recognition and boosted decision tree regression techniques for muon reconstruction, includes pileup subtraction for jets and energy sums, and incorporates pileup-dependent isolation requirements for electrons and tau leptons. In addition, the new trigger calculates high-level quantities such as the invariant mass of pairs of reconstructed particles. The upgrade reduces the trigger rate from background processes and improves the trigger efficiency for a wide variety of physics signals

    Pileup mitigation at CMS in 13 TeV data

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    With increasing instantaneous luminosity at the LHC come additional reconstruction challenges. At high luminosity, many collisions occur simultaneously within one proton-proton bunch crossing. The isolation of an interesting collision from the additional "pileup" collisions is needed for effective physics performance. In the CMS Collaboration, several techniques capable of mitigating the impact of these pileup collisions have been developed. Such methods include charged-hadron subtraction, pileup jet identification, isospin-based neutral particle "δβ" correction, and, most recently, pileup per particle identification. This paper surveys the performance of these techniques for jet and missing transverse momentum reconstruction, as well as muon isolation. The analysis makes use of data corresponding to 35.9 fb1^{-1} collected with the CMS experiment in 2016 at a center-of-mass energy of 13 TeV. The performance of each algorithm is discussed for up to 70 simultaneous collisions per bunch crossing. Significant improvements are found in the identification of pileup jets, the jet energy, mass, and angular resolution, missing transverse momentum resolution, and muon isolation when using pileup per particle identification
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