Publications by authors named "Francisco A Monteiro"

Manganese (Mn) is essential for plants but very toxic at high rates. However, hyperaccumulators can tolerate high Mn concentrations in plant tissue, especially when properly fertilized with N. Tanzania guinea grass (Megathyrsus maximus Jacq.

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Soil contamination caused by improper waste disposal can affect plant growth. Tropical forage plants have rapid growth, high biomass production and vigorous regrowth. Chromium (Cr) is one of the most common contaminants in the environment.

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Wireless networks beyond 5G will mostly be serving myriads of sensors and other machine-type communications (MTC), with each device having different requirements in respect to latency, error rate, energy consumption, spectral efficiency or other specifications. Multiple-input multiple-output (MIMO) systems remain a central technology towards 6G, and in cases where massive antenna arrays or cell-free networks are not possible to deploy and only moderately large antenna arrays are allowed, the detection problem at the base-station cannot rely on zero-forcing or matched filters and more complex detection schemes have to be used. The main challenge is to find low complexity, hardware feasible methods that are able to attain near optimal performance.

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Plants used for phytoextraction of metals need to tolerate toxicity conditions. Potassium (K) participates in physiological and biochemical processes that can alleviate toxicity by heavy metals, including cadmium (Cd). This study aimed to evaluate the effect of K on photosynthesis and on the changes in the antioxidant system of tanzania guinea grass [Panicum maximum Jacq.

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Sulfur (S) can play essential roles in protecting plants against abiotic stress, including heavy metal toxicity. However, the effect of this nutrient on plants exposed to barium (Ba) is still unknown. This study was designed to evaluate the S supply on oxidative stress and the antioxidant system of Tanzania guinea grass under exposure to Ba, grown in a nutrient solution under greenhouse conditions.

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Silicon (Si) is a beneficial element which was proven to enhance the tolerance of plants to excess metal in a given growth medium. However, the efficacy of Si in mitigating Cu toxicity in plants can vary between plant species and with the amount of copper (Cu) present in the soil/medium. An experiment was performed to investigate the role of Si in alleviating Cu toxicity in Tanzania guinea grass (Panicum maximum cv.

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The supply of potassium (K) is a strategy to increase the tolerance of plants exposed to Cd toxicity. The aim of this study was to verify the influence of K on the growth and potential of Tanzania guinea grass (Panicum maximum Jacq. cv.

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Plants benefit from the simultaneous uptake of nitrate (NO) and ammonium (NH), which can influence the bioaccumulation of heavy metals. Nevertheless, there are no studies on the effect of nitrogen forms on grasses used for cadmium (Cd) phytoextraction. The objective was to evaluate the response of Panicum maximum cv.

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In order to grow and effectively uptake and accumulate cadmium (Cd), plants used for phytoextraction have to cope with toxicity, which may be influenced by the supply of nitrate (NO) and ammonium (NH). Thus, we evaluated the effect of these nitrogen forms on the photosynthetic and antioxidant enzyme activities of Panicum maximum cv. Tanzania (tanzania guinea grass) under Cd stress.

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Various nitrate and ammonium proportions (NO/NH) in the growth media can increase metal phytoextraction compared to supplying solely NO. However, there are no studies showing these effects in plants under copper (Cu) contamination as well as their consequences in plant stress tolerance. The objective was to evaluate the effect of NO/NH proportions in Cu phytoextraction by Panicum maximum cv.

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Nitrogen (N) can alleviate metal toxicity. However, as of yet, there have been no studies showing the efficacy of NO/NH in mitigating Cu toxicity. The objective of this study was to evaluate the Cu toxicity on the nutritional and productive attributes of Panicum maximum cv.

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With the growth of the world population, cadmium (Cd) concentration in the environment has increased considerably as a result of human activities such as foundry, battery disposal, mining, application of fertilizers containing toxic elements as impurities, and disposal of metal-containing waste. Higher plants uptake N as ammonium (NH), nitrate (NO ), and many other water-soluble compounds such as urea and amino acids, and nourishing plants with N, providing part of it as NH, is an interesting alternative to the supply of this nutrient in the exclusive form of NO under Cd toxicity. The objective was to evaluate the influence of NO /NH proportions on the development and tolerance of tomato plants grown under the presence of Cd in the culture medium.

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Soil acidity and the associated problems of aluminum (Al) toxicity and scarce exchangeable bases are typically the most important limiting factors of agricultural yield in wet tropical regions. The goals of this study were to test how soil lime rates affect the forms and distribution of Al in the soil fractions and how different levels of bioavailable Al affect two tomato genotypes grown in wet tropical soils. The tomato genotypes CNPH 0082 and Calabash Rouge were grown in two wet tropical soils in a greenhouse.

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Tropical and subtropical soils are usually acidic and have high concentrations of aluminum (Al). Aluminum toxicity in plants is caused by the high affinity of the Al cation for cell walls, membranes, and metabolites. In this study, the response of the antioxidant-enzymatic system to Al was examined in two tomato genotypes: Solanum lycopersicum var.

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Objective: To investigate the risk factors associated with oliguria and death in obstetric patients with acute kidney injury (AKI).

Methods: The study group included all obstetric patients with AKI, under dialytic treatment, in Hospital Geral César Cals, Fortaleza, Brazil, from January 2000 to December 2006. AKI were classified according to the RIFLE criteria.

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