Looking for imprints of the first stellar generations in metal-poor bulge field stars

© 2016 ESO. Context. Efforts to look for signatures of the first stars have concentrated on metal-poor halo objects. However, the low end of the bulge metallicity distribution has been shown to host some of the oldest objects in the Milky Way and hence this Galactic component potentially offers interesting targets to look at imprints of the first stellar generations. As a pilot project, we selected bulge field stars already identified in the ARGOS survey as having [Fe/H] 1 and oversolar [α/Fe] ratios, and we used FLAMES-UVES to obtain detailed abundances of key elements that are believed to reveal imprints of the first stellar generations. Aims. The main purpose of this study is to analyse selected ARGOS stars using new high-resolution (R ∼ 45 000) and high-signal-tonoise (S=N > 100) spectra. We aim to derive their stellar parameters and elemental ratios, in particular the abundances of C, N, the α-elements O, Mg, Si, Ca, and Ti, the odd-Z elements Na and Al, the neutron-capture s-process dominated elements Y, Zr, La, and Ba, and the r-element Eu. Methods. High-resolution spectra of five field giant stars were obtained at the 8 m VLT UT2-Kueyen telescope with the UVES spectrograph in FLAMES-UVES configuration. Spectroscopic parameters were derived based on the excitation and ionization equilibrium of Fe i and Fe ii. The abundance analysis was performed with a MARCS LTE spherical model atmosphere grid and the Turbospectrum spectrum synthesis code. Results.We confirm that the analysed stars are moderately metal-poor (-1:04≤[Fe/H]≤-0:43), non-carbon-enhanced (non-CEMP) with [C/Fe] ≤+0:2, and α-enhanced.We find that our three most metal-poor stars are nitrogen enhanced. The α-enhancement suggests that these stars were formed from a gas enriched by core-collapse supernovae, and that the values are in agreement with results in the literature for bulge stars in the same metallicity range. No abundance anomalies (Na-O, Al-O, Al-Mg anti-correlations) were detected in our sample. The heavy elements Y, Zr, Ba, La, and Eu also exhibit oversolar abundances. Three out of the five stars analysed here show slightly enhanced [Y/Ba] ratios similar to those found in other metal-poor bulge globular clusters (NGC 6522 and M 62). Conclusions. This sample shows enhancement in the first-to-second peak abundance ratios of heavy elements, as well as dominantly s-process element excesses. This can be explained by different nucleosynthesis scenarios: (a) the main r-process plus extra mechanisms, such as the weak r-process; (b) mass transfer from asymptotic giant branch stars in binary systems; (c) an early generation of fast-rotating massive stars. Larger samples of moderately metal-poor bulge stars, with detailed chemical abundances, are needed to better constrain the source of dominantly s-process elements in the early Universe

Caracterização de linhagens de soja Glycine max (L.) Merrill para produção de brotos.

Orientadoras: Juliana Steffens, Clarice Steffens e Mercedes Concórdia Carrão-Panizzi

Fauna edáfica como indicadora de contaminação do solo.

Recentemente, o solo tem se tornado foco de preocupação devido à gradativa contaminação de ambientes terrestres e aquáticos, decorrente do progresso e avanços sócio-econômicos no país. Diante dessa realidade, a demanda por atividades antrópicas menos agressivas ao ambiente é cada vez maior. Os possíveis impactos ambientais, portanto, devem ser monitorados, controlados e remediados, a fim de evitar problemas irreversíveis ao meio ambiente e à sociedade. A ecotoxicologia estuda os efeitos dos poluentes sobre os organismos e a interação destes com o habitat. Para se avaliar o impacto de uma substância no solo, ensaios ecotoxicológicos com metodologia padronizada internacionalmente podem ser realizados com invertebrados edáficos, tais como as minhocas, enquitreídeos e colêmbolos, por serem importantes na decomposição da matéria orgânica do solo. Esses ensaios de laboratório, no entanto, precisam ser adaptados, pois a metodologia padrão se baseia em espécies e condições de clima temperado que não condizem com a realidade do Brasil. Adaptações aos ensaios de efeito agudo (mortalidade), efeito crônico (reprodução) e de fuga (comportamento) têm sido estudados por vários grupos e os resultados têm sido positivos com relação ao uso do substrato com o pó da fibra da casca do côco e utilização de temperaturas maiores que 20ºC. Algumas espécies encontradas no Brasil também têm sido testadas, algumas delas apresentando resultados promissores, outras, com limitações. De modo geral, os métodos para avaliação da contaminação do solo em laboratório têm apresentado avanços, entretanto, mais estudos se fazem necessários para o estabelecimento de espécies nativas recomendadas para cada tipo de ensaio.Resumo expandido

Improvement in soybean sprouts production with ultrasound power.

The present work aimed the application of different ultrasound powers (10, 50 and 90W) to evaluate the germination and characteristics of soybean sprouts fromsoybeans of cultivar BRS 216 and 3 lines (A, B and C). In the germination test,the line A showed the highest percentage of germination (96% for 90W).The cultivar BRS 216 and line A present lower values of weight and higher yield of sprouts. The viable sprouts that presented the highest weight (for each 50g of soybean) were: line A followed by BRS 216, line C and B, with statistical differences (p<0.05) between them. For each 50g of soybean of cultivar BRS 216 and Lines A, B and C the production of viable sprouts was 231.47; 237.87; 170.74 and 199.94g, respectively, for 90W. In relation to the length of the sprouts using the power of 10W the line C presented a longer length. The line A using 90W showed better color characteristics. The highest protein value was found in cultivar BRS 216, for all applied potencies. With this work it can be concluded that the line A would be the most suitable for sprout production regardless of the ultrasound power applie

Use of a Raspberry-Pi Video Camera for Coastal Flooding Vulnerability Assessment: The Case of Riccione (Italy)

Coastal monitoring is strategic for the correct assessment of nearshore morphodynamics, to verify the effects of anthropogenic interventions for the purpose of coastal protection and for the rapid assessment of flooding vulnerability due to severe events. Remote sensing and field surveys are among the main approaches that have been developed to meet these necessities. Key parameters in the assessment and prevision of coastal flooding extensions, beside meteomarine characteristics, are the topography and slope of beaches, which can be extremely dynamic. The use of continuous monitoring through orthorectified video images allows for the rapid detection of the intertidal bathymetry and flooding threshold during severe events. The aim of this work was to present a comparison of different monitoring strategies and methodologies that have been integrated into repeated surveys in order to evaluate the performance of a new camera system. We used a low-cost camera based on Raspberry Pi called VISTAE (Video monitoring Intelligent STAtion for Environmental applications) for long-term remote observations and GNSS-laser tools for field measurements. The case study was a coastal tract in Riccione, Italy (Northern Adriatic Sea), which is the seat of nourishment interventions and of different types of underwater protection structures to combat coastal erosion. We performed data acquisition and analysis of the emerged beach and of the swash zone in terms of the intertidal bathymetry and shoreline. The results show a generally good agreement between the field and remote measurements through image processing, with a small discrepancy of the order of ≈0.05 m in the vertical and ≈1.5 m in the horizontal in terms of the root mean square error (RMSE). These values are comparable with that of current video monitoring instruments, but the VISTAE has the advantages of its low-cost, programmability and automatized analyses. This result, together with the possibility of continuous monitoring during daylight hours, supports the advantages of a combined approach in coastal flooding vulnerability assessment through integrated and complementary techniques

Acompanhamento de um biodigestor de fluxo ascendente para tratamento de efluentes da suinocultura.

Projeto/Plano de Ação: 02.07.06.007

Comparative study of the phase transition of Li1+xMn2-xO4 by anelastic spectroscopy and differential scanning calorimetry

Li1+xMn2xO4 is one of the most promising candidates as high performance cathode for lithium ion batteries. The stoichiometric compound is known to undergo a phase transition around room temperature, which has been widely studied and attributed either to Jahn–Teller effect or to charge ordering. For the applications it is important to suppress this phase transition, which lowers the electrochemical performances of the material. DSC measurements, which have been largely used in the literature to study the occurrence of the transformation, can detect a phase transition accompanied by latent heat only for x < 0.04. This fact has been generally accepted as a proof that the transformation is suppressed by doping. However, by using a technique extremely sensitive to rearrangements of atoms in the lattice, such as anelastic spectroscopy, we show that the phase transition persists up to x = 0.08, is shifted to lower temperatures, and changes its nature from first to higher order. The implications for the mechanism driving the transition and the similarities and differences with doped Fe3O4, which is the prototype of charge order transitions, are discussed

Efeito do tebuconazol no comportamento de fuga de Eisenia andrei em ensaios de laboratórios com solo natural.

FertBio 2010

Duodenal-jejunal Bypass Normalizes Pancreatic Islet Proliferation Rate And Function But Not Hepatic Steatosis In Hypothalamic Obese Rats

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Modifications in life-style and/or pharmacotherapies contribute to weight loss and ameliorate the metabolic profile of dietinduced obese humans and rodents. Since these strategies fail to treat hypothalamic obesity, we have assessed the possible mechanisms by which duodenal-jejunal bypass (DJB) surgery regulates hepatic lipid metabolism and the morphophysiology of pancreatic islets, in hypothalamic obese (HyO) rats. During the first 5 days of life, male Wistar rats received subcutaneous injections of monosodium glutamate (4 g/kg body weight, HyO group), or saline (CTL). At 90 days of age, HyO rats were randomly subjected to DJB (HyO DJB group) or sham surgery (HyO Sham group). HyO Sham rats were morbidly obese, insulin resistant, hypertriglyceridemic and displayed higher serum concentrations of non-esterified fatty acids (NEFA) and hepatic triglyceride (TG). These effects were associated with higher expressions of the lipogenic genes and fatty acid synthase (FASN) protein content in the liver. Furthermore, hepatic genes involved in beta-oxidation and TG export were down-regulated in HyO rats. In addition, these rats exhibited hyperinsulinemia, beta-cell hypersecretion, a higher percentage of islets and beta-cell area/pancreas section, and enhanced nuclear content of Ki67 protein in islet-cells. At 2 months after DJB surgery, serum concentrations of TG and NEFA, but not hepatic TG accumulation and gene and protein expressions, were normalized in HyO rats. Insulin release and Ki67 positive cells were also normalized in HyO DJB islets. In conclusion, DJB decreased islet-cell proliferation, normalized insulinemia, and ameliorated insulin sensitivity and plasma lipid profile, independently of changes in hepatic metabolism.505Fundacao Araucaria [155/2013, 393/2013]Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2015/12611-0]Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP