109 research outputs found
Yield of tifton 85 grass under irrigation and nitrogen doses
O trabalho foi conduzido em uma propriedade de atividade leiteirana município de Xambrê, região Noroeste do Paraná, no período de março de 2011 a fevereiro de 2012 com o objetivo de avaliar a produtividade e a composição botânica do capim Tifton 85 com e sem irrigação sob doses de nitrogênio. As parcelas experimentais foram implantadas com delineamento de blocos ao acaso com e sem irrigação e as subparcelas por meio de quatro doses de nitrogênio: 0, 20, 40 e 60 kg ha-1 ciclo de pastejo-1, com quatro repetições. A produtividade em matéria seca (MS) foi maior sob irrigaçãocrescendo de forma linear à adubação nitrogenada. Na dose de 60 kg N ha-1 foram obtidas produtividades iguais a 39279 e 27826 kg MS ha-1, com e sem irrigação, respectivamente. A relação folha colmo não foi afetada pela irrigação. A média geral do percentual de material morto com e sem irrigação, foi igual a 13 e 17%, respectivamente194317323The study was conducted on a dairy farm in the municipality of Xambre, Northwest region of Parana, in the period from March 2011 to February 2012 to evaluate the yield and botanical composition of Tifton 85 with and without irrigation under nitrogen doses. The experimental plots were implanted in completely randomized blocks with and without irrigation and subplots through four nitrogen levels: 0, 20, 40 and 60 kg ha(-1) per grazing cycle, with four replications. The yield in dry matter (DM) was higher under irrigation, responding linearly to increasing nitrogen fertilization. At a dose of 60 kg N ha(-1) yields of 39279 and 27826 kg DM ha(-1) were obtained, with and without irrigation, respectively. The leaf stem ratio was not affected by irrigation. The overall mean percentage of dead material with and without irrigation was equal to 13 and 17%, respectivel
The BINGO Project IX: Search for Fast Radio Bursts -- A Forecast for the BINGO Interferometry System
The Baryon Acoustic Oscillations (BAO) from Integrated Neutral Gas
Observations (BINGO) radio telescope will use the neutral Hydrogen emission
line to map the Universe in the redshift range , with
the main goal of probing BAO. In addition, the instrument optical design and
hardware configuration support the search for Fast Radio Bursts (FRBs). In this
work, we propose the use of a BINGO Interferometry System (BIS) including new
auxiliary, smaller, radio telescopes (hereafter \emph{outriggers}). The
interferometric approach makes it possible to pinpoint the FRB sources in the
sky. We present here the results of several BIS configurations combining BINGO
horns with and without mirrors ( m, m, and m) and 5, 7, 9, or 10 for
single horns. We developed a new {\tt Python} package, the {\tt FRBlip}, which
generates synthetic FRB mock catalogs and computes, based on a telescope model,
the observed signal-to-noise ratio (S/N) that we used to compute numerically
the detection rates of the telescopes and how many interferometry pairs of
telescopes (\emph{baselines}) can observe an FRB. FRBs observed by more than
one baseline are the ones whose location can be determined. We thus evaluate
the performance of BIS regarding FRB localization. We found that BIS will be
able to localize 23 FRBs yearly with single horn outriggers in the best
configuration (using 10 outriggers of 6 m mirrors), with redshift ; the full localization capability depends on the number and the type of
the outriggers. Wider beams are best to pinpoint FRB sources because potential
candidates will be observed by more baselines, while narrow beams look deep in
redshift. The BIS can be a powerful extension of the regular BINGO telescope,
dedicated to observe hundreds of FRBs during Phase 1. Many of them will be well
localized with a single horn + 6 m dish as outriggers.(Abridged)Comment: 12 pages, 9 figures, 5 tables, submitted to A&
The BINGO Project IV: Simulations for mission performance assessment and preliminary component separation steps
The large-scale distribution of neutral hydrogen (HI) in the Universe is
luminous through its 21 cm emission. The goal of the Baryon Acoustic
Oscillations from Integrated Neutral Gas Observations -- BINGO -- radio
telescope is to detect baryon acoustic oscillations (BAOs) at radio frequencies
through 21 cm intensity mapping (IM). The telescope will span the redshift
range 0.127 0.449 with an instantaneous field-of-view of . In this work we investigate different constructive and
operational scenarios of the instrument by generating sky maps as they would be
produced by the instrument. In doing this we use a set of end-to-end IM mission
simulations. The maps will additionally be used to evaluate the efficiency of a
component separation method (GNILC). We have simulated the kind of data that
would be produced in a single-dish IM experiment such as BINGO. According to
the results obtained, we have optimized the focal plane design of the
telescope. In addition, the application of the GNILC method on simulated data
shows that it is feasible to extract the cosmological signal across a wide
range of multipoles and redshifts. The results are comparable with the standard
principal component analysis method.Comment: 16 pages. Version to appear in A&
The germline mutational landscape of BRCA1 and BRCA2 in Brazil
The detection of germline mutations in BRCA1 and BRCA2 is essential to the formulation of clinical management strategies, and in Brazil, there is limited access to these services, mainly due to the costs/availability of genetic testing. Aiming at the identification of recurrent mutations that could be included in a low-cost mutation panel, used as a first screening approach, we compiled the testing reports of 649 probands with pathogenic/likely pathogenic variants referred to 28 public and private health care centers distributed across 11 Brazilian States. Overall, 126 and 103 distinct mutations were identified in BRCA1 and BRCA2, respectively. Twenty-six novel variants were reported from both genes, and BRCA2 showed higher mutational heterogeneity. Some recurrent mutations were reported exclusively in certain geographic regions, suggesting a founder effect. Our findings confirm that there is significant molecular heterogeneity in these genes among Brazilian carriers, while also suggesting that this heterogeneity precludes the use of screening protocols that include recurrent mutation testing only. This is the first study to show that profiles of recurrent mutations may be unique to different Brazilian regions. These data should be explored in larger regional cohorts to determine if screening with a panel of recurrent mutations would be effective.This work was supported in part by grants from Barretos Cancer Hospital (FINEP - CT-INFRA, 02/2010), Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP, 2013/24633-2 and 2103/23277-8), Fundação de Apoio à Pesquisa do Rio Grande do Norte (FAPERN), Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS), Ministério da Saúde, the Breast Cancer Research Foundation (Avon grant #02-2013-044) and National Institute of Health/National Cancer Institute (grant #RC4 CA153828-01) for the Clinical Cancer Genomics Community Research Network. Support in part was provided by grants from Fundo de Incentivo a Pesquisa e Eventos (FIPE) from Hospital de Clínicas de Porto Alegre, by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES, BioComputacional 3381/2013, Rede de Pesquisa em Genômica Populacional Humana), Secretaria da Saúde do Estado da Bahia (SESAB), Laboratório de Imunologia e Biologia Molecular (UFBA), INCT pra Controle do Câncer and Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq). RMR and PAP are recipients of CNPq Productivity Grants, and Bárbara Alemar received a grant from the same agencyinfo:eu-repo/semantics/publishedVersio
SARS-CoV-2 uses CD4 to infect T helper lymphocytes
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here, we show that SARS-CoV-2 infects human CD4+ T helper cells, but not CD8+ T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS-CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.</p
SARS-CoV-2 uses CD4 to infect T helper lymphocytes
The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the agent of a major global outbreak of respiratory tract disease known as Coronavirus Disease 2019 (COVID-19). SARS-CoV-2 infects mainly lungs and may cause several immune-related complications, such as lymphocytopenia and cytokine storm, which are associated with the severity of the disease and predict mortality. The mechanism by which SARS-CoV-2 infection may result in immune system dysfunction is still not fully understood. Here, we show that SARS-CoV-2 infects human CD4+ T helper cells, but not CD8+ T cells, and is present in blood and bronchoalveolar lavage T helper cells of severe COVID-19 patients. We demonstrated that SARS-CoV-2 spike glycoprotein (S) directly binds to the CD4 molecule, which in turn mediates the entry of SARS-CoV-2 in T helper cells. This leads to impaired CD4 T cell function and may cause cell death. SARS-CoV-2-infected T helper cells express higher levels of IL-10, which is associated with viral persistence and disease severity. Thus, CD4-mediated SARS-CoV-2 infection of T helper cells may contribute to a poor immune response in COVID-19 patients.</p
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The pace of life for forest trees.
Tree growth and longevity trade-offs fundamentally shape the terrestrial carbon balance. Yet, we lack a unified understanding of how such trade-offs vary across the world's forests. By mapping life history traits for a wide range of species across the Americas, we reveal considerable variation in life expectancies from 10 centimeters in diameter (ranging from 1.3 to 3195 years) and show that the pace of life for trees can be accurately classified into four demographic functional types. We found emergent patterns in the strength of trade-offs between growth and longevity across a temperature gradient. Furthermore, we show that the diversity of life history traits varies predictably across forest biomes, giving rise to a positive relationship between trait diversity and productivity. Our pan-latitudinal assessment provides new insights into the demographic mechanisms that govern the carbon turnover rate across forest biomes
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