161 research outputs found

    Microorganisms from corn stigma with biocontrol potential of Fusarium verticillioides.

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    ABSTRACT - The mycotoxigenic fungus Fusarium verticillioides is the primary maize pathogen and causes the maize stalk and ear rot diseases with significant economic losses. Furthermore, the excessive use of fungicides to control F. verticillioides constitutes threats to the environment and human health. Thus, sustainable alternatives such as biological control are needed to minimize the hazards associated with the current method. Although much is known about the vulnerability of the maize silks as a gateway for several fungal pathogens invading the developing grains, studies on the chemical properties of silk extracts and their resident microbiota are scarce. This study isolated and characterized bacteria and fungi that colonize the maize stigma to assess new potential biocontrol agents. The samples were collected from maize fields in the Brazilian localities of Sete Lagoas-MG, Sidrolândia-MS, Sertaneja-PR, and Goiânia-GO. One hundred sixty-seven microorganisms were isolated, 46% endophytic and 54% epiphytic. First, the antagonist activity was evaluated by the agar disc diffusion method performed in triplicate, and 83% of the isolates showed antagonist activity against F. verticillioides. Then, the 42 most efficient isolates were identified based on the partial sequencing of the bacterial 16S rRNA gene and fungi ITS region. The bacteria belong to the genera Bacillus (57.1%), Burkholderia (23.8%), Achromobacter (7.1%), Pseudomonas (2.4%), and Serratia (2.4%), while the fungi are Penicillium (2.4%), Candida (2.4), and Aspergillus (2.4%). The results showed that microorganisms from maize stigma might represent new promising agents for F. verticillioides control. RESUMO - O fungo micotoxigênico Fusarium verticillioides é o principal patógeno do milho e causa doenças do colmo e da podridão da espiga com perdas econômicas significativas. Além disso, o uso excessivo de fungicidas no controle de F. verticillioides constitui uma ameaça ao meio ambiente e à saúde humana. Assim, alternativas sustentáveis, como o controle biológico, são necessárias para minimizar os riscos associados ao método atual. Este estudo isolou e caracterizou bactérias e fungos que colonizam o estigma do milho para avaliar novos agentes de biocontrole em potencial. As amostras foram coletadas em campos de milho nas localidades brasileiras de Sete Lagoas-MG, Sidrolândia-MS, Sertaneja-PR e Goiânia-GO. Cento e sessenta e sete microrganismos foram isolados, 46% endofíticos e 54% epifíticos. O teste de antagonismo empregando a técnica de disco de difusão em meio sólido, mostrou que 83% dos isolados apresentaram atividade antagonista contra F. verticillioides. Em seguida, 42 isolados mais eficientes foram identificados a partir do sequenciamento parcial do gene 16S rRNA bacteriano e da região ITS de fungos. Os isolados bacterianos pertencem ao gênero Bacillus (57,1%), Burkholderia (23,8%), Achromobacter (7,1%), Pseudomonas (2,4%) e Serratia (2,4%), enquanto os fungos são Penicillium (2,4%), Candida (2.4), e Aspergillus (2,4%). Os resultados mostraram que microrganismos do estigma do milho podem representar novos agentes promissores para o controle de F. verticillioides

    Tecido urbano e mercado imobiliário em São Paulo: metodologia de estudo com base na Décima Urbana de 1809

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    Este artigo apresenta uma metodologia inédita de espacialização da Décima Urbana, primeiro imposto predial estabelecido para as cidades brasileiras. Focaliza o caso de São Paulo, em 1809. Os dados recolhidos na documentação textual foram processados em banco de dados e cartografados na primeira planta cadastral da cidade, elaborada pelo engenheiro Carlos Bresser, entre 1844-1847, e confrontados com a documentação iconográfica dos viajantes e de Militão Augusto de Azevedo, de modo a precisar as informações obtidas. A Décima Urbana de 1809 contém informações sobre a localização dos imóveis, seus proprietários, inquilinos, tipologias (casas térreas, sobrados, lojas), finalidades (uso próprio, aluguel), usos (residencial, comercial, misto) e valor, que hoje nos permitem reconstituir hipoteticamente o velho tecido urbano da cidade de São Paulo e aspectos da dinâmica do seu mercado imobiliário em fins do período colonial.This article presents a new spatialisation methodology for the Décima Urbana, the first property tax established in Brazilian cities. The case of São Paulo in 1809 is studied. The data gathered from textual documentation was processed in a database and cartographed on the first official city plan, elaborated by engineer Carlos Bresser between 1844-1847, and then confronted with the iconographic documentation produced by visiting travellers and by photographer Militão Augusto de Azevedo, so as to cross-reference the information obtained. The Décima Urbana of 1809 contains data about the siting of buildings, their proprietors, tenants, typology (single and two-storey houses, shops), finalities (own use, rent), uses (residential, commercial, mixed) and value. This allows for the present day hypothetical reconstruction of old São Paulo's urban mesh and of aspects of the real estate market dynamics at the end of the colonial period

    The BINGO Project IX: Search for Fast Radio Bursts -- A Forecast for the BINGO Interferometry System

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    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 0.127z0.4490.127 \le z \le 0.449, 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 (44 m, 55 m, and 66 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 z0.96z \leq 0.96; 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&

    Guarana (Paullinia cupana var. sorbilis), an anciently consumed stimulant from the Amazon rain forest: the seeded-fruit transcriptome.

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    Guarana (Paullinia cupana var. sorbilis) is a plant native to the central Amazon basin. Roasted seed extracts have been used as medicinal beverages since pre-Colombian times, due to their reputation as stimulants, aphrodisiacs, tonics, as well as protectors of the gastrointestinal tract. Guarana plants are commercially cultivated exclusively in Brazil to supply the national carbonated soft-drink industry and natural product stores around the world. In this report, we describe and discuss the annotation of 15,387 ESTs from guarana seeded-fruits, highlighting sequences from the flavonoid and purine alkaloid pathways, and those related to biotic stress avoidance. This is the largest set of sequences registered for the Sapindaceae family

    Increase in Non-AIDS Related Conditions as Causes of Death among HIV-Infected Individuals in the HAART Era in Brazil

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    Background. In 1996, Brazil became the first developing country to provide free and universal access to HAART. Although a decrease in overall mortality has been documented, there are no published data on the impact of HAART on causes of death among HIV-infected individuals in Brazil. We assessed temporal trends of mortality due to cardiovascular diseases (CVD), diabetes mellitus (DM) and other conditions generally not associated with HIV-infection among persons with and without HIV infection in Brazil between 1999 and 2004. Methodology/Principal Findings. Odds ratios were used to compare causes of death in individuals who had HIV/AIDS listed on any field of the death certificate with those who did not. Logistic regression models were fitted with generalized estimating equations to account for spatial correlation; co-variables were added to the models to control for potential confounding. Of 5,856,056 deaths reported in Brazil between 1999 and 2004 67,249 (1.15%) had HIV/AIDS listed on the death certificate and non-HIV-related conditions were listed on 16.3% in 1999, Increasing to 24.1% by 2004 (p<0.001) The adjusted average yearly increases were 8% and 0.8% for CVD (p<0.001), and 12% and 2.8% for DM (p<0.001), for those who had and kiki not have HIV/AIDS listed on the death certificate respectively. Similar results were found for these conditions as underlying causes of death. Conclusions/Significance. In Brazil between 1999 and 2004 conditions usually considered not to be related to HIV-infection appeared to become more likely causes of death over time than reported causes of death among individuals who had HIV/AIDS listed on the death certificate than in those who did not. This observation has important programmatic implications for developing countries that are scaling-up access to antiretroviral therapy. © 2008 Pacheco et al

    The BINGO project: II. Instrument description

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    Context. The measurement of diffuse 21-cm radiation from the hyperfine transition of neutral hydrogen (Hi signal) in different redshifts is an important tool for modern cosmology. However, detecting this faint signal with non-cryogenic receivers in single-dish telescopes is a challenging task. The BINGO (Baryon Acoustic Oscillations from Integrated Neutral Gas Observations) radio telescope is an instrument designed to detect baryonic acoustic oscillations (BAOs) in the cosmological Hi signal, in the redshift interval 0:127 ≤ z ≤ 0:449. Aims. This paper describes the BINGO radio telescope, including the current status of the optics, receiver, observational strategy, calibration, and the site. Methods. BINGO has been carefully designed to minimize systematics, being a transit instrument with no moving dishes and 28 horns operating in the frequency range 980 ≤ v ≤ 1260 MHz. Comprehensive laboratory tests were conducted for many of the BINGO subsystems and the prototypes of the receiver chain, horn, polarizer, magic tees, and transitions have been successfully tested between 2018-2020. The survey was designed to cover ∼13% of the sky, with the primary mirror pointing at declination δ = -15°. The telescope will see an instantaneous declination strip of 14:75. Results. The results of the prototype tests closely meet those obtained during the modeling process, suggesting BINGO will perform according to our expectations. After one year of observations with a 60% duty cycle and 28 horns, BINGO should achieve an expected sensitivity of 102μK per 9.33MHz frequency channel, one polarization, and be able to measure the Hi power spectrum in a competitive time frame
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