Composición del circón de granitos variscos del Norte de Portugal

A group of slightly peraluminous Variscan plutons in Northern Portugal were selected from the study of zircon composition. The selected plutons are: the Vila Pouca de Aguiar and the Lavadores-Madalena plutons with I-type affinities and the Vieira do Minho pluton, an l-S transitional type. Zircon occurs as euhedral to subhedral crystals and exhibit finely concentric oscillatory magmatic zoning mainly related to variations of Hf, Y, U and Th concentrations. Most zircon crystals show the dominant “xenotime” substitution. The zircon crystals have Zr/Hf ratio in the range of 21 to 52, with no significant differences between the different granites. These values are in the same range of other peraluminous granites and are in accordance with a crustal signature of zircon. Moreover, the range of Zr/Hf values in zircon crystals overlaps with that of crustal sources and consequently to the potential protoliths proposed in the genesis of the Vieira do Minho and the Vila Pouca de Aguiar plutons, namely meta-igneous crustal sources at different levels. Although zircon from the Lavadores-Madalena pluton has a compositional range similar to the other plutons, an origin by hibridisation has been proposed. However, similar zircon chemistry between this pluton and Vila Pouca de Aguiar and Vieira do Minho plutons could also suggest a similar crustal source.Se han seleccionado tres plutones graniticos variscos en el norte de Portugal para el estudio de la composición del circón. Los plutones son: Vila Pouca de Aguiar y Lavadores-Madalena con afinidad de tipo-I y el plutón de Vieira do Minho de tipo transicional I-S. Los circones se presentan en cristales euhédricos a subhédricos y tienen zonados magmáticos, concéntricos oscilatorios finos ligados principalmente a variaciones de las concentraciones del Hf, Y, U y Th. La mayoría de los cristales de circón muestran la sustitución dominante “xenotima”. Los zircones tienen relaciones Zr/Hf que varían en el rango 21–52, sin diferencias significativas entre los diferentes granitos. Estos valores son idénticos a otros granitos peralumínicos y son consistentes con circones de origen cortical. Además, las relaciones Zr/Hf coinciden con las de protolitos corticais y, en consecuencia con los propuestos en la génesis de los plutones de Vila Pouca de Aguiar y Vieira de Minho, en particular rocas metaigneas. Aunque los circones del plutón Lavadores-Madalena tienen una composicíon similar a los otros plutones, fue propuesto un origen por hibridacíon. Sin embargo la similitud química de los circones de este plutón con los otros puede tambíen sugerir un origen similar

Los efectos térmicos del Complejo Plutónico de Santa Eulalia (sur de Portugal) en las rocas metaígneas y metasedimentarias encajantes

The Santa Eulália Plutonic Complex (SEPC) is a late-Variscan granitic body located in the northern part of the Ossa Morena Zone, a inner zone of the Variscan Iberian Massif. The SEPC host rocks are composed of meta-igneous and metasedimentary units, from Upper Proterozoic to Paleozoic ages, with a NW-SE structure, cross-cut by the SEPC. The SEPC host rocks, with low grade metamorphism show well preserved primary sedimentary or igneous mineralogical, textural and structural features. The thermal effect induced by the SEPC is restricted to the roof pendants. At N and NE of the SEPC, textures and paragenesis resulting from thermal metamorphism, are not related to the SEPC intrusion but to a previous magmatism, controlled by the NW-SE regional anisotropies. The restriction of the thermal effects to the pluton roof may be caused by a combination of several interrelated factors: higher volume of granitic mass, thermal effect by advection of fluids and longer period of prevalence of high thermal conditions. The geochemical study of SEPC host rocks shows the heterogeneous character and diversity of metasedimentary, igneous and meta-igneous rocks. The whole rock geochemical data indicate that all the metasedimentary lithologies derived from an upper continental crustal source and the igneous and meta-igneous rocks show no evidence of metasomatic effects by the SEPC emplacement.El Complejo Plutónico de Santa Eulalia (CPSE) es un cuerpo granítico tardi-Varisco situado en la parte norte de la Zona de Ossa Morena, en la zona interior del Macizo Ibérico Varisco. Las rocas encajantes del CPSE están compuestas por unidades meta-ígneas y metasedimentarias, de edades que van desde el Proterozoico Superior hasta el Paleozoico, con una estructura de dirección NW-SE, cortada por el CPSE. Las rocas encanjantes del CPSE, con metamorfismo de bajo grado conservan estructuras, mineralogía y textura primarias. El efecto térmicoinducido por el CPSE se limita a los roof pendants. Al N y NE del CPSE, las texturas y paragénesis resultantes del metamorfismo térmico, no están relacionadas con la intrusión del CPSE sino con un magmatismo anterior, controlado por anisotropías regionales NW- SE. La restricción de los efectos térmicos al techo del pluton puede ser causada por una combinación de varios factores interrelacionados: mayor volumen de masa granítica, un efecto térmico por la advección de fluidos y el período de prevalencia de altas condiciones térmicas. Los datos geoquímicos de las rocas encanjantes del CPSE muestran el carácter heterogéneo y la diversidad de rocas sedimentarias, metasedimentarias, ígneas y meta-ígneas. El análisis de los datos geoquímicos indica que todas las litologías sedimentarias y metasedimentarias han derivado de la corteza continental superior, mientras las rocas ígneas y meta-ígneas tienen una composición que no muestra evidencias de efectos metasomáticos por el emplazamiento del CPSE

Medium-chain triglyceride supplementation may increase working memory in older adults: A pilot study

Poster presentatio

Production of bioactive lichen compounds by alginate-immobilized bionts isolated from Cladonia verticillaris: an in vitro study

Bionts isolated from thalli of Cladonia verticillaris, immobilized in calcium alginate, produce two depsidones, fumarprotocetraric and protocetraric acids, and the depside atranorin, that exhibit antimicrobial activity against Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. Organic lichen extract (acetone/ether/chloroform) shows the highest antimicrobial activity due to a possible synergism between these substances. Antioxidant capacity of soluble metabolites secreted from the immobilisates to the bath medium of incubation during the first 12 days of immobilization has been found (˃80% oxidation inhibition). The concentration of soluble phenolic substances depends on the immobilization time (during 32 days), exogenous supply of acetate (1.0m mM sodium or calcium acetate) and on the type of isolated biont (phycobionts, mycobionts, whole thallus or immobilized phycobionts co-incubated with the mycobionts ones). The role of phycobionts in phenol production has been interpreted as a possible modification of the polymalonyl pathway; for example, atranorin is actively produced and secreted during immobilization while it is not detected in thallus in natura. Co-incubated bionts secrete higher amounts of atranorin to the media during the first 12 days of immobilization. Immobilization of isolated bionts could be used as a biotechnological technique to obtain a potential source of biological active compounds. On the other hand, the physiological state detected of C. verticillaris in the Cerrado is much better for experimentation than that of the specimens collected in Caatinga since, in this case, the thalli showed the fragility that the extreme environmental conditions of the semi-arid region of NE Brazil impose on this lichen species. To date, no priority has been defined for lichen conservation in Brazilian ecosystems. It is therefore suggested that it imust important to include lichen ecophysiology studies in public conservation policies

Biologically-active compounds from Brazilian lichens and their affinity with ether

It can be obtained from lichens biologically-active extracts and pure substances, many of them of phenolic nature. They are usually obtained by using organic solvents, such as diethyl ether. In this paper the usefulness of ether for the obtainment of crude extracts and the subsequent purification of pure substances from Brazilian lichen is reviewed, as well as alternatives to their production through cells or thallus immobilization in bioreactors and their entrapment in inert matrix

TrkB-targeted therapy for mucoepidermoid carcinoma

The brain-derived neurotrophic factor (BDNF)/tyrosine receptor kinase B (TrkB) pathway was previously associated with key oncogenic outcomes in a number of adenocarcinomas. The aim of our study was to determine the role of this pathway in mucoepidermoid carcinoma (MEC). Three MEC cell lines (UM-HMC-2, H253 and H292) were exposed to Cisplatin, the TrkB inhibitor, ANA-12 and a combination of these drugs. Ultrastructural changes were assessed through transmission electron microscopy; scratch and Transwell assays were used to assess migration and invasion; and a clonogenic assay and spheroid-forming assay allowed assessment of survival and percentage of cancer stem cells (CSC). Changes in cell ultrastructure demonstrated Cisplatin cytotoxicity, while the effects of ANA-12 were less pronounced. Both drugs, used individually and in combination, delayed MEC cell migration, invasion and survival. ANA-12 significantly reduced the number of CSC, but the Cisplatin effect was greater, almost eliminating this cell population in all MEC cell lines. Interestingly, the spheroid forming capacity recovered, following the combination therapy, as compared to Cisplatin alone. Our studies allowed us to conclude that the TrkB inhibition, efficiently impaired MEC cell migration, invasion and survival in vitro, however, the decrease in CSC number, following the combined treatment of ANA-12 and Cisplatin, was less than that seen with Cisplatin alone; this represents a limiting factor

Diet and lifestyle changes during the COVID-19 pandemic in Ibero-American countries: Argentina, Brazil, Mexico, Peru, and Spain

This study aimed to evaluate changes in dietary and lifestyle habits during the period of confinement due to the first wave of the COVID-19 pandemic in Ibero-American countries. A cross-sectional investigation was conducted with 6,325 participants of both genders (68% women), over 18 years of age and from five countries: Brazil (N = 2,171), Argentina (N = 1,111), Peru (N = 1,174), Mexico (N = 686), and Spain (N = 1,183). Data were collected during the year 2020, between April 01 and June 30 in Spain and between July 13 and September 26, in the other countries studied using a self-administered online survey designed for the assessment of sociodemographic, employment, physical activity, health status, and dietary habits changes. Most participants (61.6%), mainly those from Spain, remained constant, without improving or worsening their pattern of food consumption. Among those who changed, a pattern of better eating choices prevailed (22.7%) in comparison with those who changed toward less healthy choices (15.7%). Argentina and Brazil showed the highest proportion of changes toward a healthier pattern of food consumption. Peruvians and Mexicans were less likely to make healthy changes in food consumption (OR: 0.51; 95% CI: 0.4–0.6 and OR: 0.69; 95% CI: 0.4–0.8, respectively), when compared to Argentinians. Most respondents did not change their pattern of meal consumption, but those who did reduced their consumption of main meals and increased intake of small meals and snacks. Although most participants affirmed to be doing physical activity at home, about one-half reported perception of weight gain. Individuals with alterations in sleep pattern (either by increasing or decreasing sleep time) were more likely to change their diets to a healthier pattern. In contrast, individuals with confirmed diagnosis of COVID-19 and those who reported feeling anxious were more likely to perform changes to a less healthy eating pattern (OR: 1.72; 95% CI: 1.2–2.3 and OR: 1.21; 95% CI: 1.1–1.4, respectively). In conclusion, although most participants remained constant in their eating habits, lifestyle changes and anxiety feelings were reported. Among those who changed patterns of food consumption, healthier choices prevailed, with differences between countries. However, there were alterations in the distribution of meals, with higher consumption of snacks and small meals. These results can be used to guide policies to prevent deleterious consequences that may affect the incidence of chronic diseasesWe acknowledge the National Council for Scientific and Technological Development (CNPq) which provided MCBM a productivity fellowship and the Coordination for the Improvement of Higher Education Personnel (CAPES) which granted OE-M a Ph.D. scholarship. The project developed in Spain was supported by the Program of R&D activities between research groups of the Community of Madrid in Social Sciences and Humanities, co-financed with the European Social Fund (H2019/HUM-5802

Big Bang nucleosynthesis and cosmic microwave background constraints on the time variation of the Higgs vacuum expectation value

We derive constraints on the time variation of the Higgs vacuum expectation value $$ through the effects on Big Bang nucleosynthesis (BBN) and the cosmic microwave background (CMB). In the former case, we include the (previously-neglected) effect of the change in the deuteron binding energy, which alters both the $^4$He and deuterium abundances significantly. We find that the current BBN limits on the relative change in \higgs are $-(0.6 - 0.7) \times 10^{-2} / < (1.5 - 2.0) \times 10^{-2}$, where the exact limits depend on the model we choose for the dependence of the deuteron binding energy on \higgs.The limits from the current CMB data are much weaker.Comment: 5 pages including 5 figures, accepted for publication in Phys. Rev.

Drosophila nasuta (Diptera, Drosophilidae) in Brazil: a decade of invasion and occupation of more than half of the country

Abstract As a result of human activities and natural dispersal, exotic species can be brought to new areas, where they become established and spread, becoming invaders. These species are responsible for the loss of biodiversity and cause ecosystemic harm throughout the world. In this paper, we report the rapid, broad geographic expansion of the invasive fly Drosophila nasuta in Brazil. An 84% increase was found in its area of occupation in the country compared to previous studies. The present data reveal its arrival to the Pantanal wetlands in a location more than one thousand kilometers from the closest previous record in the Cerrado biome. We present the first record of D. nasuta in the Atlantic Forest in the states of Paraíba and Bahia. We report its introduction in the Amazon Forest in the state of Amazonas approximately 700 kilometers from previous records. The relative abundance of D. nasuta in this biome increased fivefold in comparison to a previous study. In the first decade of invasion in Brazil, D. nasuta has already colonized more than half of the country. The present data reveal its invasive potential and underscore the importance of following up the possible negative effects of this biological invasion