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The culture of coffee is very important in Brazilian scenery. Brazil is the world's largest coffee producer, responsible for 30% of the planet's production, and it is among the 15 largest coffee consuming nations. More and more, consumers look for better quality of coffee, and the presence of determinate composts would prejudice the health of the consumers. Therefore, this study suggests a method to identify and quantify commercially roasted ground coffee impurities/contaminants using computed microtomography (micro‐CT) and x‐ray fluorescence (XRF) techniques. A set of different commercially roasted ground coffees were investigated. The micro‐CT results showed that most of the coffee powder samples analyzed showed some contaminant, and in a specific brand, the amount of contaminants was higher than 9%. The 3D data provided information about the size and shape of these contaminants. The XRF results showed the macro elements P, S, Cl, K, and Ca and the micro elements Mn, Fe, Cu, Zn, Rb, and Sr. The elemental concentrations are in agreement with the values reported in the literature, except for the same specific brand, where the values found were much higher. The combined data of both techniques showed that the amount of impurities/contaminants in the ground coffee results in an increase of the macro and micro nutrients and also modifies the flavor and fragrance of the product, leading to an overall poor quality of the final beverage. [ABSTRACT FROM AUTHOR]

Atmospheric particulate matter (PM) is considered to be a set of pollutants suspended in the air, from industrial processes, motor vehicle exhaust, resuspended street dust, biomass burning, and others. Among the toxic chemical compounds, PM is considered contaminants of great importance for researchers, as they offer harmful effects to humans, fauna and flora. Moreover, exposure to PM can cause the development and/or worsening of diseases, mainly respiratory and cardiovascular. The aim of the present study was to evaluate the metals concentration in total suspended particulate matter in the air through total reflection x‐ray fluorescence technique (TXRF). The samples were collected from random points in five neighborhoods in the Metropolitan Region of the state of Rio de Janeiro/Brazil. TXRF measurements were performed using the benchtop TXRF spectrometer S2 PICOFOX. The results showed that the proposed methodology was able to detect the elements Cr, Fe, Ni, Cu, and Zn, in concentrations ranging from 2.0 to 200 ng.m−3. It can be concluded that the study methodology for determining the metal concentrations in air samples is an efficient and low‐cost solution for studying environmental pollution. [ABSTRACT FROM AUTHOR]

Composed of hydrocarbons and other substances, petroleum is classified as a nonrenewable source of energy. In its unrefined form, it is called crude oil. Currently, its derivates are widely used in domestic and industrial environments, with the greatest exponent being motor fuels and lubricating oils. Due to the overwhelming demand, new oil wells in the presalt region of Brazil are going to be drilled, which will, in its turn, increase the demand for analysis and require the use of less costly technologies. The purpose of this paper is to present an experimental method that aims at characterizing crude oil samples through their X‐ray scattering profiles without the need for any chemical preparation to be performed in advance, which will enable this method to be used for analyzing samples immediately after their extraction. For the experiment, a portable X‐ray scattering system composed by an X‐ray tube (silver anode) and a Si‐PIN detector was used in order to analyze samples from different wells. The process consisted in establishing a linear relationship between the effective atomic number and the ratio between peak intensities of Compton and Rayleigh scattering from known samples. The linear function, verified experimentally, was then applied to samples of crude oil, and the results showed that it is possible to characterize them on the basis of the Rayleigh to Compton scattering ratio. After the analysis, a multiple comparison test performed on the samples proved that this methodology indeed allows to differentiate samples of different origins and to verify the compatibility of samples extracted from the same well. [ABSTRACT FROM AUTHOR]

An X-ray Transmission Microtomography (CT) system combined with an X-ray Fluorescence Microtomography (XRFCT) system was implemented in the Brazilian Synchrotron Light Laboratory (LNLS), Campinas, Brazil. The main of this work is to determine the elemental distribution map in reference samples and breast tissue samples in order to verify the concentration of some elements correlated with characteristics and pathology of each tissue observed by the transmission CT. The experiments were performed at the X-Ray Fluorescence beamline (D09B-XRF) of the Brazilian Synchrotron Light Laboratory, Campinas, Brazil. A quasi-monochromatic beam produced by a multilayer monochromator was used as an incident beam. The sample was placed on a high precision goniometer and translation stages that allow rotating as well as translating it perpendicularly to the beam. The fluorescence photons were collected with an energy dispersive HPGe detector placed at 900 to the incident beam, while transmitted photons were detected with a fast Na(Tl) scintillation counter placed behind the sample on the beam direction. The CT images were reconstructed using a filtered-back projection algorithm and the XRFCT were reconstructed using a filtered-back projection algorithm with absorption corrections. [ABSTRACT FROM AUTHOR]

In this work, 960 réis coins from the period when Brazil was a colony of Portugal were analyzed using the x-ray fluorescence (XRF) spectrometry. The history of these coins, dated between the end of the 17th century and the beginning of the 19th century, had a great influence on the immigration of the Portuguese Prince Regent D. João to Brazil, who arrived in 1808. Bearing in mind the need to expand the timid Brazilian monetary system, the Portuguese crown decided to collect Spanish silver pesos of 8 reales , recoined with a value of 960 réis. The recoinage procedure was carried out using a stamp; therefore, in many cases, it is possible to check the base currency. In this work, were investigated 17 samples of 960 réis coins by XRF, in which the base coin was 8 reales manufactured with raw materials from Mexican mines. In addition to characterizing the elemental composition of the coins, the XRF data were evaluated using multivariate statistical method of Robust Principal Component Analysis (ROBPCA), which was used to classify the coins based on their elemental composition. However, with XRF, elementary information is obtained for a depth of only a few micrometers. One of the essential issues in Ag–Cu metal alloys is the Ag enrichment, which can cause changes to the elemental composition of the surface. Therefore, initially, a study was carried out to verify whether the surface compositions of the coins were altered by the Ag enrichment. Image 1 • Analysis of Brazilian coins of 960 réis by XRF. • Robust Principal Component Analysis (ROBPCA) applied to XRF data. • Ag enrichment study by XRF. [ABSTRACT FROM AUTHOR]

Leposternon microcephalum is a species belonging to the Amphisbaenia, a group of burrowing reptiles. Amphisbaenia present various morphological and physiological adaptations that allow them to penetrate the ground and live underground, through a system of galleries and permanent chambers that they build themselves. Among the morphological adaptations in this group, those of the skull stand out as it serves as the main excavation tool. Four basic skull shapes are recognized: rounded, keeled, shovel-shaped, and spade-shaped. The skull of L. microcephalum belongs to this last type, which is considered the most specialized. The species inhabits soils that are highly compacted and difficult to penetrate. Among the species of Leposternon present in South America, L. microcephalum has the widest distribution, being found in all Brazilian biomes and neighboring countries such as Bolivia, Argentina, Paraguay, and Uruguay. The analysis of the skull of this species was carried out using three-dimensional geometric morphometrics (3D-GMM), a technique that allows comparative analysis, through robust statistical methods, of shape and its variations, using Cartesian coordinate data from a configuration of homologous landmarks. The technique allows the size and shape components of a structure to be analyzed separately. From an ontogenetic point of view, this methodology had also been used to investigate variations in Cynisca leucura, a member of the Amphisbaenidae with a rounded head. Our hypothesis is that the patterns of morphological differentiation in the skull, mainly in the intermediate and occipital regions, are similar in different Amphisbaenia species. Therefore, the objective of this study was to analyze cranial morphological variations in an ontogenetic series of L. microcephalum using 3D-GMM. Computed Tomographic scans of 13 specimens were analyzed: juveniles (N = 8) and adults (N = 5), based on 20 landmarks that characterize the skull. Principal components and regression analyses between shape (dependent variable) and size (independent variable) showed a clear difference between the cranial morphological pattern of juvenile individuals and that of adults. For instance, young specimens tend to have a dorsoventrally tall neurocranium, with the tip of the snout more anteriorly oriented and its dorsal border subtly curved. Dorsally, the parietal region is thicker and smoothly dome-shaped in juveniles. As in C. leucura, the variation was strongly correlated with the size change from juvenile to adult, indicating a dominant role for ontogenetic allometry in determining skull shape., (© 2023 Wiley Periodicals LLC.)

Abstract: Riostegotherium yanei from the Itaboraí Basin, Brazil, is the oldest known Xenarthra. This paper aims to describe the internal morphology of the osteoderms of Riostegotherium yanei from the perspective of histology and micro-CT approaches, expanding the available data on cingulate osteoderm microstructure. Seven osteoderms of R. yanei were used for the internal microstructure description and eight of Dasypus novemcinctus for comparison. The osteoderms of Riostegotherium yanei lacks the diploë-like structure typical of glyptodonts but has a three-layered structure composed of two layers of non-Haversian compact bone enclosing a central layer of primary and secondary osteons. This internal organization is distinct from other Astegotheriini of comparable age, but similar to Dasypus. The 3D reconstruction of Riostegotherium yanei revealed two patterns of internal organization. Pattern 1 of movable osteoderm is composed of large remodeled areas at the base and a more compact bone at the tongue; in Pattern 2 (both movable and buckler), the internal cavities are much smaller, more numerous, and more interconnected to each other. In one buckler osteoderm, the cavities are organized somewhat radially with a compact central region (Pattern 1). Pattern 1 of both movable and buckler osteoderms resemble that of Dasypus.

The potentiometric titration method was used for characterization of uranium compounds to be applied in intercomparison programs. The method is applied with traceability assured using a potassium dichromate primary standard. A semi-automatic version was developed to reduce the analysis time and the operator variation. The standard uncertainty in determining the total concentration of uranium was around 0.01%, which is suitable for uranium characterization and compatible with those obtained by manual techniques., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The Nuclear Medicine Services (NMS) in Brazil routinely use dose calibrators to measure the activity of solutions containing radiopharmaceuticals. These solutions are administered to patients with the intention to diagnose or treat illnesses. However, for optimal results, the activity of these radiopharmaceuticals must be determined as accurately as possible. The National Laboratory for Ionizing Radiation Metrology (LNMRI) led, since 1998, a comparison program for activity measurements of radiopharmaceuticals administered to patients in the NMS with the purpose promoting quality control. This program has been carried out successfully in Rio de Janeiro, but there is a need to implement it around the country. This can be resolved through the implementation of a network of regional laboratories at various locations throughout the national territory. Currently, such a network is active at a second site, located in Brasília, covering the needs of the Center-West Region, and at a third site, located in Porto Alegre, in the South Region. This work presents the results of comparisons for the radiopharmaceuticals nuclides 131I and 99Tcm and proves that the implementation of a radionuclide metrology network is feasible and viable.

Since 1998, the National Laboratory for Ionizing Radiation Metrology has lead an intercomparison program for activity measurements of radiopharmaceuticals administered to patients in the Nuclear Medicine Services (NMS) with the purpose of promoting the quality control. In this work, intercomparison results with the radionuclides 67Ga, 123I, 99mTc and 201Tl from the beginning of the program to the present will be presented establishing as a consequence, the radionuclide calibrators' traceability used by the participants. The analysis of the results showed that 68% were within the limits of +/-10% required by the Brazilian Regulatory Authority that demands this accuracy band for the radiopharmaceutical measurements in the NMS. The results also demonstrate an improvement in the measurement quality that this program has provided since its beginning.