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Integrated petrographic and chemical analysis of zircon, garnet and rutile from ultrahigh-temperature (UHT) granulites in the Anápolis–Itauçu Complex, Brazil, is used to constrain the significance of zircon ID-TIMS U–Pb geochronological data. Chondrite-normalized rare earth element (REE) profiles of zircon cores have positive-sloping heavy-REE patterns, commonly inferred to be magmatic, whereas unambiguous metamorphic grains and overgrowths have flat to slightly negatively sloping heavy-REE patterns. However, in one sample, a core of zircon interpreted as having formed prior to garnet crystallization and a metamorphic zircon formed within microstructures involving garnet breakdown both display elevated heavy-REE (and Y) with positive-sloping patterns. DREE(zrc/grt) partition coefficients suggest an approximation to equilibrium between zircon and garnet cores, although progressive enrichment in heavy REE towards garnet rims occurs in two of the samples investigated. Titanium-in-zircon thermometry indicates zircon growth during both the prograde and post-peak evolution, but not at peak temperatures of the UHT metamorphism. By contrast, zirconium-in-rutile thermometry of inclusions armoured by garnet records crystallization temperatures, based on the upper end of the interquartile range of the data, of ∼890 to 870 °C and maximum temperature around 980 °C, indicating prograde and retrograde growth close to and after peak conditions. Rutile located in retrograde microstruct records crystallization temperatures of 850 to 820 °C. Rutile intergrown with ilmenite and included within orthopyroxene, which is associated with exsolved zircon, records temperatures ∼760 °C, consistent with Ti-in-zircon crystallization temperatures. ID-TIMS U–Pb geochronological data from two of the four samples investigated define upper intercept ages of 641.3 ± 8.4 Ma (MSWD 0.91) and 638.8 ± 2.5 Ma (MSWD 1.03) that correlate with periods of zircon growth along the prograde segment of the P–T path. Individual zircon U–Pb dates retrieved from all samples range from 649 to 634 Ma, indicating a maximum duration of c. 15 Myr for the UHT event. This period is interpreted as recording modest thickening of hot backarc lithosphere located behind the Arenópolis Arc at the edge of the São Francisco Craton consequent upon terminal collision of the Parána Block with the arc during the amalgamation of West Gondwana. [ABSTRACT FROM AUTHOR]

Mining has become one of the main factors in the global biogeochemical cycle of potentially toxic elements. Therefore, it is considered one of the anthropogenic activities with the greatest negative impact on the environment. These impacts are maximized in semiarid regions, where mining activities can lead to soil degradation and decrease in land productivity. This study aimed to assess the level of contamination in natural, urban, and agricultural soils of three important mining areas, where approximately 80,000 people live, and pollution levels have never been determined before. For this purpose, soil samples were collected around iron, uranium, and vanadium mines, as well as in the main human settlements of the region. The concentrations of 34 elements were determined by instrumental neutron analysis activation (INAA) and inductively coupled plasma optical emission spectrometry (ICP OES) techniques. Pollution indices (CF, EF, mCd, PLI, and REEP) revealed that there is a moderate to heavy level of pollution for 89% of the analyzed elements. Additionally, an extreme contamination level was observed in 78% of the samples, for at least one element. Statistical analyses were performed to identify patterns in the distribution and common sources of pollution. The results suggest that the concentrations for Al, Ba, Hf, Na, Pb, Rb, REE, Ta, Th, U, Zn, and Zr are associated with geogenic causes. However, the influence of anthropogenic sources such as agriculture and mining on the accumulation of these elements in soils should not be disregarded. In contrast, the contents of As, Br, Cd, Co, Cr, Cs, Cu, Fe, K, Mn, Ni, Sc, Ti, and V reflect the direct impact of anthropogenic sources. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the independent and interactive effects of situational variables, opposition team formation, and playing position on running performance and network analysis in Brazilian professional soccer players (n = 22). Global positioning system technology was used to determine total distance covered, mean speed, maximum running speed, and distance covered in 6 speed ranges. Social network analysis was used to assess interpersonal coordination (team interactions characterized as successful passes [n = 3,033] between teammates). Observations of match running performance (n = 129) and network analysis (n = 108) were obtained. The main results were: (a) no interactive effects between team formation and playing position were observed for running and network variables (unclear to possibly); (b) matches played at home or against "weaker" opponents presented greater running demands and individual/global metrics of network analysis (likely to almost certain); (c) match outcome demonstrated influence only for running performance; matches in which the reference team won resulted in higher values than in matches lost; (d) when the reference team competed in 1-4-4-2 formation, this resulted in greater running demands than 1-4-2-3-1 formation (likely to almost certain); (e) reduced values of running performance variables were reported in central defenders compared with other positions. Central/external midfielders reported greater closeness/betweenness centrality, outdegree, and eigenvector compared with central/external defenders and forwards (likely to almost certain). The results from this study provide practical information to potentially impact on physical, tactical, and technical training. [ABSTRACT FROM AUTHOR]

Despite the recent discoveries of considerable fossil fuel reserves, Brazil is one of the only great economic and industrial powers with very high amounts of renewable energy in its electricity matrix. Approximately 79.3% of the electric energy supply comes from renewable resources, of which hydroelectric power represents 70.6%. The two primary concerns regarding hydroelectricity are the damage caused to the environment by the construction of dams and the uncertainty of the supply in cases of long drought seasons. This article presents an analysis on the availability and energy exploitation of sugarcane straw and forest residues derived from eucalyptus for decentralized generation using a Geographic Information System–based model. The potential bioelectricity and bioethanol production from sugarcane and eucalyptus biomass in the Administrative Region of Campinas (ARC) is higher than the demand in this region. The results provide guidelines for designing alternatives to the intended Nationally Determined Contributions in Brazil within the scope of the ARC, and they can be used to provide energy empowerment, electric matrix diversification, and new policies that address the residue availability and demand. [ABSTRACT FROM AUTHOR]

Aim: This study investigated the mortality rate distribution in Brazilian cities based on skin color/race and according to level of urbanicity and aggregation into metropolitan region (MR) in 2010. Subjects and methods: The age-adjusted all-cause mortality rate (AMR) was calculated according to skin color/race (white, brown, or black). Municipalities were used as analysis units and classified into six categories: Rural within MR; Rural outside MR; 'Rurbano' within MR; 'Rurbano' outside MR; Urban within MR and Urban outside MR. Results: Racial inequality intensified in line with increasing urbanicity level, from rural to urban areas. However, these differences depended on how the city was aggregated to MR, thus suggesting that the mortality spatial structure was based on skin color or race in these locations. The black population presented the worst AMR risk, mainly in cities outside MR. In addition, it was found that there was an excess mortality in the black population as compared with white people. Conclusion: Mortality-related racial inequalities were associated with urbanicity and MR level. They were also dependent on a complex combination of risk factors in these areas. City categorization may serve as an intervention point to reduce racial inequalities in health among populations in Brazilian cities. [ABSTRACT FROM AUTHOR]

Tradescantia names from Vellozo's Flora fluminensis are revised, five lectotypes and one epitype are designated; one name is accepted and three names are treated as synonyms. Notes on Tradescantia sect. Austrotradescantia and Tradescantia sect. Cymbispatha are presented, based on the studies of Vellozo's names. Also, further notes on the Brazilian Tradescantia and a key for the sections occurring in Brazil are here presented. [ABSTRACT FROM AUTHOR]

The trace element content of zircon grains from Holocene beach sands from the Rio Grande do Sul state in southern Brazil was investigated in order to discuss their probable primary source. Zircon grains from 10 samples were separated and analysed by laser ablation inductively coupled plasma mass spectrometer (LA ICP-MS) for rare earth elements (REE), niobium (Nb), uranium (U), thorium (Th), yttrium (Y), hafnium (Hf), and tantalum (Ta) and by microprobe and scanning electron microscopy (SEM) for silicon (Si), zirconium (Zr), and phosphorus (P). The results obtained are similar to those suggested by the zircon classification developed by BELOUSOVA et al. (2002, Igneous zircon: trace element composition as an indicator on source rock type. Contributions to Mineralogy and Petrology, 143, 602-622), nevertheless, additional information and a more detailed characterisation of zircon sources were yielded. The probable geotectonic setting and geochemical affinity of zircon igneous sources were predicted mainly based on thorium/uranium (Th/U), yttrium/holmium (Y/Ho), and niobium/tantalum (Nb/Ta) ratios; lanthanum (La) and niobium (Nb) contents; and REE patterns of zircons. The statistical groups identified by multivariate analysis were an additional useful tool for identifying compositional groups of zircons. Zircon grains from the studied sediments are probably derived from an association of subalkaline to alkaline granitic rocks with their mafic counterparts and metamorphic rocks of amphibolite to granulite facies. The metamorphic sources were more important in the southern sector of the studied coastal segment, whilst in the northern sector zircons from A-type granites are more abundant. The so-called Pelotas Batholith, situated in the eastern part of the Sul-rio-grandense Shield, which is composed mainly of a postcollisional granitic association of Neoproterozoic age and Paleo to Neoproterozoic high-grademetamorphic sequences, is proposed as the probable source of the studied zircons. The compositional variations of zircons from the southern to the northern sector are coherent with the hypothesis that the studied sediments came from relatively near continental source areas, probably transported by several small streams and rivers during phases of sea-level low stands. The chemical composition of zircons, particularly trace element contents and ratios, can be a powerful tool for determining the primary sources of detrital zircons. [ABSTRACT FROM AUTHOR]

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Background: In patients with type 2 diabetes mellitus (DM), an accurate assessment of food intake is essential for clinical nutritional management. Tools such as the food frequency questionnaire (FFQ) and 24-h food record (24HR) identify dietary habits in support of dietary planning. However, it is possible that these tools have reporting errors with respect to assessing food intake, particularly energy intake (EI)., Methods: A cross-sectional study was conducted in patients with type 2 DM. EI was assessed by the FFQ and 24HR tools. Resting energy expenditure (REE) was measured by indirect calorimetry. Data were analysed using a kappa test, t-test and Spearman's correlation coefficients. Under-reporting was assessed using the EI/REE ratio. Patients with values <1.18 and <1.10 for FFQ and 24HR, respectively, were considered as under-reporting., Results: We evaluated 55 patients [mean (SD) 62.7 (5.3) years old, duration of diabetes 11.2 (7.3) years, 52.7% female]. The mean (SD) EI assessed by FFQ was 1797.7 (641.3) and as assessed by 24HR was 1624 (484.8) kcal day -1 . The mean (SD) REE was 1641.3 (322.3) kcal day -1 . The mean (SD) ratios FFQ/REE and 24HR/REE were 1.11 (0.38) and 1.01 (0.30), respectively. The tools showed a moderate agreement for under-reporting of EI (kappa = 0.404; P = 0.003). Moderate and positive correlations between REE were observed with FFQ (r = 0.321; P = 0.017) and 24HR (r = 0.364; P = 0.006). According to the tools, the under-reporting was observed in approximately 65% of patients., Conclusions: The majority of patients with type 2 DM under-reported their calorie intake, as assessed by FFQ and 24HR. REE showed a positive correlation with both tools., (© 2020 The British Dietetic Association Ltd.)