15 research outputs found

    A Theoretical Approach to Predict the Fatigue Life of Flexible Pipes

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    This paper focuses on a theoretical approach to access the fatigue life of flexible pipes. This methodology employs functions that convert forces and moments obtained in time-domain global analyses into stresses in their tensile armors. The stresses are then processed by well-known cycle counting methods, and S-N curves are used to evaluate the fatigue damage at several points in the pipe’s cross-section. Finally, Palmgren-Miner linear damage hypothesis is assumed in order to calculate the accumulated fatigue damage. A study on the fatigue life of a flexible pipe employing this methodology is presented. The main points addressed in the study are the influence of friction between layers, the effect of the annulus conditions, the importance of evaluating the fatigue life in various points of the pipe’s cross-section, and the effect of mean stresses. The results obtained suggest that the friction between layers and the annulus conditions strongly influences the fatigue life of flexible pipes. Moreover, mean stress effects are also significant, and at least half of the wires in each analyzed section of the pipe must be considered in a typical fatigue analysis

    Association between nitrogen and seed inoculation with bacteria diazotrĂłpica in Maize

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    O Brasil Ă© o terceiro maior produtor mundial de milho e mais de 50% desta produção estĂĄ concentrada no Cerrado. Esta produção estĂĄ relacionada ao fornecimento adequado de nutrientes, especialmente o nitrogĂȘnio (N), que Ă© fornecido via adubação mineral, contudo a inoculação das sementes com bactĂ©rias diazotrĂłpicas tem complementado as necessidades da cultura. Neste estudo avaliou-se o desenvolvimento e a produção da cultura do milho cultivado com diferentes doses de N, na presença e ausĂȘncia de Azospirillum. Com delineamento de blocos casualizados em esquema fatorial (5 x 2), sendo cinco doses de N (0, 50, 100, 150 e 200 kg ha-1), duas formas de inoculação da bactĂ©ria (1 – Com, 2 – Sem), com seis repetiçÔes. Mediu-se a altura da planta, inserção, comprimento e diĂąmetro da espiga, massa de mil grĂŁos, percentual de grĂŁos ardidos e produtividade. A inoculação das sementes de milho com a bactĂ©ria Azospirillum brasilense melhora a eficiĂȘncia da planta na absorção do nitrogĂȘnio disponĂ­vel. O diĂąmetro de espiga e a produtividade aumentaram linearmente com as doses de nitrogĂȘnio na presença da bactĂ©ria. A inoculação da semente com a bactĂ©ria nĂŁo substitui o uso de fertilizantes nitrogenados, mas melhora a resposta da planta Ă  adubação, especialmente em doses elevadas.Brazil is the world's third largest producer of corn and over 50% of this production is concentrated in the Cerrado. This production is related to adequate supply of nutrients, especially nitrogen (N), which is provided via mineral fertilization, however the inoculation of seeds with bacteria has complemented the needs of culture. This study evaluated the development and production of cultivated maize with different doses of N in the presence and absence of Azospirillum. With a randomized block design in a factorial scheme (5 x 2), with five N rates (0, 50, 100, 150 and 200 kg ha-1), two forms of inoculation of bacteria (1 - with, 2 - Without) with six replications. Measured the height of the plant, insertion length and diameter of the ear, thousand grain weight, percentage of crop burned and productivity. The inoculation of corn seeds with the bacterium Azospirillum brasilense improves the efficiency of the plant in the uptake of nitrogen available. The diameter of the cob and productivity increased linearly with the dose of nitrogen in the presence of the bacteria. The inoculation of seed with the bacterium does not replace the use of nitrogenous fertilizers, but improves the response of the plant to nitrogen, especially in high doses.Facultad de Ciencias Agrarias y Forestale

    Association between nitrogen and seed inoculation with bacteria diazotrĂłpica in Maize

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    Brazil is the world's third largest producer of corn and over 50% of this production is concentrated in the Cerrado. This production is related to adequate supply of nutrients, especially nitrogen (N), which is provided via mineral fertilization, however the inoculation of seeds with bacteria has complemented the needs of culture. This study evaluated the development and production of cultivated maize with different doses of N in the presence and absence of Azospirillum. With a randomized block design in a factorial scheme (5 x 2), with five N rates (0, 50, 100, 150 and 200 kg ha-1), two forms of inoculation of bacteria (1 - with, 2 - Without) with six replications. Measured the height of the plant, insertion length and diameter of the ear, thousand grain weight, percentage of crop burned and productivity. The inoculation of corn seeds with the bacterium Azospirillum brasilense improves the efficiency of the plant in the uptake of nitrogen available. The diameter of the cob and productivity increased linearly with the dose of nitrogen in the presence of the bacteria. The inoculation of seed with the bacterium does not replace the use of nitrogenous fertilizers, but improves the response of the plant to nitrogen, especially in high doses.O Brasil Ă© o terceiro maior produtor mundial de milho e mais de 50% desta produção estĂĄ concentrada no Cerrado. Esta produção estĂĄ relacionada ao fornecimento adequado de nutrientes, especialmente o nitrogĂȘnio (N), que Ă© fornecido via adubação mineral, contudo a inoculação das sementes com bactĂ©rias diazotrĂłpicas tem complementado as necessidades da cultura. Neste estudo avaliou-se o desenvolvimento e a produção da cultura do milho cultivado com diferentes doses de N, na presença e ausĂȘncia de Azospirillum. Com delineamento de blocos casualizados em esquema fatorial (5 x 2), sendo cinco doses de N (0, 50, 100, 150 e 200 kg ha-1), duas formas de inoculação da bactĂ©ria (1 – Com, 2 – Sem), com seis repetiçÔes. Mediu-se a altura da planta, inserção, comprimento e diĂąmetro da espiga, massa de mil grĂŁos, percentual de grĂŁos ardidos e produtividade. A inoculação das sementes de milho com a bactĂ©ria Azospirillum brasilense melhora a eficiĂȘncia da planta na absorção do nitrogĂȘnio disponĂ­vel. O diĂąmetro de espiga e a produtividade aumentaram linearmente com as doses de nitrogĂȘnio na presença da bactĂ©ria. A inoculação da semente com a bactĂ©ria nĂŁo substitui o uso de fertilizantes nitrogenados, mas melhora a resposta da planta Ă  adubação, especialmente em doses elevadas

    Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

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    The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

    Anais do V Encontro Brasileiro de Educomunicação: Educação midiĂĄtica e polĂ­ticas pĂșblicas

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    A presente coletĂąnea, que chega ao pĂșblico atravĂ©s de um suporte digital, tem como objetivo disponibilizar os papers, bem como os relatos de experiĂȘncias educomunicativas apresentados durante o V ENCONTRO BRASILEIRO DE EDUCOMUNICAÇÃO, que teve como tema central: “Educação MidiĂĄtica e PolĂ­ticas PĂșblicas”. O evento foi realizado em SĂŁo Paulo, entre 19 e 21 de setembro de 2013, a partir de uma parceria entre o NCE/USP - NĂșcleo de Comunicação e Educação da USP, a Licenciatura em Educomunicação da ECA/USP, a ABPEducom – Associação Brasileira de Pesquisadores e Profissionais da Educomunicação e a FAPCOM – Faculdade Paulus de Tecnologia e Comunicação, que ofereceu seu campus, na Vila Mariana, para os atos do evento. Os presentes anais disponibilizam o texto de abertura, de autoria do coordenador geral do evento, denominado “Educação midiĂĄtica e polĂ­ticas pĂșblicas: vertentes histĂłricas da emergĂȘncia da Educomunicação na AmĂ©rica Latina”. Na sequĂȘncia, apresentam 61 papers sobre aspectos especĂ­ficos da temĂĄtica geral, resultantes de pesquisas na ĂĄrea, seguidos de 27 relatos de prĂĄticas educomunicativas, em nĂ­vel nacional

    Co-expression network analysis reveals transcription factors associated to cell wall biosynthesis in sugarcane

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    Lipid droplets fuel SARS-CoV-2 replication and production of inflammatory mediators.

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    Viruses are obligate intracellular parasites that make use of the host metabolic machineries to meet their biosynthetic needs. Thus, identifying the host pathways essential for the virus replication may lead to potential targets for therapeutic intervention. The mechanisms and pathways explored by SARS-CoV-2 to support its replication within host cells are not fully known. Lipid droplets (LD) are organelles with major functions in lipid metabolism, energy homeostasis and intracellular transport, and have multiple roles in infections and inflammation. Here we described that monocytes from COVID-19 patients have an increased LD accumulation compared to SARS-CoV-2 negative donors. In vitro, SARS-CoV-2 infection were seen to modulate pathways of lipid synthesis and uptake as monitored by testing for CD36, SREBP-1, PPARÎł, and DGAT-1 expression in monocytes and triggered LD formation in different human cell lines. LDs were found in close apposition with SARS-CoV-2 proteins and double-stranded (ds)-RNA in infected Vero cells. Electron microscopy (EM) analysis of SARS-CoV-2 infected Vero cells show viral particles colocalizing with LDs, suggestive that LDs might serve as an assembly platform. Pharmacological modulation of LD formation by inhibition of DGAT-1 with A922500 significantly inhibited SARS-CoV-2 replication as well as reduced production of mediators pro-inflammatory response. Taken together, we demonstrate the essential role of lipid metabolic reprograming and LD formation in SARS-CoV-2 replication and pathogenesis, opening new opportunities for therapeutic strategies to COVID-19

    Co-expression network analysis reveals transcription factors associated to cell wall biosynthesis in sugarcane

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    Sugarcane is a hybrid of Saccharum officinarum and Saccharum spontaneum, with minor contributions from other species in Saccharum and other genera. Understanding the molecular basis of cell wall metabolism in sugarcane may allow for rational changes in fiber quality and content when designing new energy crops. This work describes a comparative expression profiling of sugarcane ancestral genotypes: S. officinarum, S. spontaneum and S. robustum and a commercial hybrid: RB867515, linking gene expression to phenotypes to identify genes for sugarcane improvement. Oligoarray experiments of leaves, immature and intermediate internodes, detected 12,621 sense and 995 antisense transcripts. Amino acid metabolism was particularly evident among pathways showing natural antisense transcripts expression. For all tissues sampled, expression analysis revealed 831, 674 and 648 differentially expressed genes in S. officinarum, S. robustum and S. spontaneum, respectively, using RB867515 as reference. Expression of sugar transporters might explain sucrose differences among genotypes, but an unexpected differential expression of histones were also identified between high and low Brix° genotypes. Lignin biosynthetic genes and bioenergetics-related genes were up-regulated in the high lignin genotype, suggesting that these genes are important for S. spontaneum to allocate carbon to lignin, while S. officinarum allocates it to sucrose storage. Co-expression network analysis identified 18 transcription factors possibly related to cell wall biosynthesis while in silico analysis detected cis-elements involved in cell wall biosynthesis in their promoters. Our results provide information to elucidate regulatory networks underlying traits of interest that will allow the improvement of sugarcane for biofuel and chemicals production
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