Modern anthropogenic drought in Central Brazil unprecedented during last 700 years.

A better understanding of the relative roles of internal climate variability and external contributions, from both natural (solar, volcanic) and anthropogenic greenhouse gas forcing, is important to better project future hydrologic changes. Changes in the evaporative demand play a central role in this context, particularly in tropical areas characterized by high precipitation seasonality, such as the tropical savannah and semi-desertic biomes. Here we present a set of geochemical proxies in speleothems from a well-ventilated cave located in central-eastern Brazil which shows that the evaporative demand is no longer being met by precipitation, leading to a hydrological deficit.

One-point calibration and matrix-matching concept for quantification of potentially toxic elements in wood by LA-ICP-MS.

The aim of this work is to evaluate two quantitative methods, based on the external calibration applied in laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis, known as (i) analytical curve and (ii) one-point calibration, using the concept of matrix matching to quantify three potentially toxic elements (PTEs) in wood samples. These can biologically register changes in the abiotic environment and be applied to monitoring climate change or environmental toxicity. In this case, standard sample preparation was evaluated to prepare the standard pellets using Pinus taeda species as a matrix-matching concept.

The microwave-assisted synthesis of silica nanoparticles and their applications in a soy plant culture.

A rapid and environmentally friendly synthesis of thermodynamically stable silica nanoparticles (SiO-NPs) from heating microwave irradiation (MW) compared to conductive heating is presented, as well as their evaluations in a soy plant culture. The parameters of time and microwave power were evaluated for the optimization of the heating program. Characterization of the produced nanomaterials was obtained from the dynamic light scattering (DLS) and zeta potential analyses, and the morphology of the SiO-NPs was obtained by transmission electron microcopy (TEM) images.

The role of silver nanoparticles effects in the homeostasis of metals in soybean cultivation through qualitative and quantitative laser ablation bioimaging.

Background: Nanoparticles (NPs) are currently found in the world in the form of natural colloids and volcanic ash, as well as in anthropogenic sources, such as nanofertilizers; however, in the literature, there is still a lack of toxicological evidence, risk assessment, and regulations about the use and environmental impact of NPs in the agroindustrial system. Therefore, the aim of this work was to evaluate alterations caused by the presence of AgNPs during the development of soybean plants.

Methods: The BRS232 non-transgenic (NT) soybean plant and 8473RR (T) and INTACTA RR2 PRO (T) transgenic soybean plants were irrigated for 18 days under controlled conditions with deionized water (control), AgNPs, and AgNO.

Development and application of green and sustainable analytical methods for flavonoid extraction from waste.

Brazilian biodiversity and favourable environmental conditions open up possibilities not yet explored, showing potential to shift the country's monochromatic economy into an emancipated, diversified and sustainable economic environment. This can be made possible through the integral use of its resources, exploring every functional fraction to create novel solutions to modern problems. Biorefineries present an interesting strategy to fully use the potential of agricultural feedstocks and together with green separation methods can contribute to the generation of sustainable processes and products.