Publications by authors named "Marcia Rizzutto"

Fungi have received particular attention in regards to alternatives for bioremediation of heavy metal contaminated locales. Enzymes produced by filamentous fungi, such as phosphatases, can precipitate heavy metal ions in contaminated environments, forming metal phosphates (insoluble). Thus, this research aimed to analyze fungi for uranium biomineralization capacity.

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Using the proper size of nanoparticles as an active substrate, Surface-enhanced Raman scattering (SERS) can provide a reliable technique for detecting and identifying fungi, including Alternaria alternata, Aspergillus flavus, Fusarium verticilliodes, and Aspergillus parasiticus that have been associated to biodeterioration and biodegradation of cultural heritage materials. In this research spherical silver nanoparticles (AgNPs) of average size of 10, 30 and 60 nm were synthesized using the wet chemical method with good yield and their size and shape distributions were examined using small-angle X-ray scattering (SAXS). The protocol for fungi sample preparation proved to be critical for producing high-quality and reproducible SERS spectra.

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In this work, several attributes of the internal morphology of drupaceous fruits found in the archaeological site Monte Castelo (Rondonia, Brazil) are analyzed by means of two different imaging methods. The aim is to explore similarities and differences in the visualization and analytical properties of the images obtained via High Resolution Light Microscopy and X-ray micro-computed tomography (X-ray MicroCT) methods. Both provide data about the three-layered pericarp (exo-, meso- and endocarp) of the studied exemplars, defined by cell differentiation, vascularisation, cellular contents, presence of sclerenchyma cells and secretory cavities.

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Penicillium piscarium can be indicated as promising in the treatment of sites contaminated with uranium. Thus, this research aimed to analyze the P. piscarium dead biomass in uranium biosorption.

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This study reports the results obtained in the analysis of waste material samples generated by the industries of phosphate fertilizers, in particular, the use of specific filters in a portable X-ray fluorescence system, a simple equipment allowing the characterization, identification and quantification of low concentrations of Th and U (ppm). The industrial byproduct is classified as a Technologically-Enhanced, Naturally-Occurring Radioactive Material - TENORM, and therefore requires monitoring for its radio-toxic activity due to the presence of radioactive thorium and uranium families. From the results obtained, it is concluded that this technique is able to determine the contents of these elements to concentrations of tens of ppm in measurements of about 300 s, and a small sample amount (∼0.

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Soft-tissue preservation provides palaeobiological information that is otherwise lost during fossilization. In Brazil, the Early Cretaceous Santana Formation contains fish with integument, muscles, connective tissues, and eyes that are still preserved. Our study revealed that soft-tissues were pyritized or kerogenized in different microfacies, which yielded distinct preservation fidelities.

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Exceptionally well-preserved three-dimensional insects with fine details and even labile tissues are ubiquitous in the Crato Member Konservat Lagerstätte (northeastern Brazil). Here we investigate the preservational pathways which yielded such specimens. We employed high resolution techniques (EDXRF, SR-SXS, SEM, EDS, micro Raman, and PIXE) to understand their fossilisation on mineralogical and geochemical grounds.

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The corrosion stability of a W-DLC coated surgical AISI 316L stainless steel in Hanks' solution has been evaluated. Particle induced X-ray emission (PIXE) measurements were performed to evaluate the incorporation of potentially bioactive elements from the physiological solution. The film structure was analyzed by X-ray diffractometry and micro-Raman spectroscopy.

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Aquatic macrophytes Salvinia auriculata, Pistia stratiotes and Eichhornia crassipes were chosen to investigate the Cr(VI) reduced by root-based biosorption in a chromium uptake experiment, using a high-resolution XRF technique. These plants were grown in hydroponics medium supplied with non-toxic Cr concentrations during a 27-day metal uptake experiment. The high-resolution Cr-Kbeta fluorescence spectra for dried root tissues and Cr reference material (100% Cr, Cr(2)O(3), and CrO(3)) were measured using an XRF spectrometer.

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