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Copyright of Tanzania Journal of Health Research is the property of Tanzania Health Research User's Trust Fund and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Effects of Sn and Gd additions on the (β1 + β3) field in the Cu-11%Al-10%Mn alloy were studied by in situ X-ray diffraction, differential scanning calorimetry, non-isothermal kinetics, and magnetization measurements as a function of the temperature. The microstructures were investigated using optical microscopy and scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. The results showed that the β 3 Cu 2 AlMn + β 1 Cu 3 Al → β 3 Cu 2 AlMn reaction is strongly dependent on the heating and cooling rates. The Sn addition to the Cu-11%Al-10%Mn alloy stabilizes the ferromagnetic β3 phase. In the Sn-containing alloy, the miscibility gap transition is followed by the martensitic transformation at about 560 K. Both Sn and Gd additions have extended the stability field of the ferromagnetic β3 phase. Nonetheless, the formation of Cu5Gd precipitates slows the miscibility gap transition on heating, which may be associated with the reduction of the ferromagnetic phase amount at room temperature in the Cu11%Al10%Mn3%Gd alloy. [ABSTRACT FROM AUTHOR]

The study examines the role and consequences of the nonstoichiometric Si[O.sub.2] interfacial layers in the oxide-semiconductor interface of Si/Si[O.sub.2] on the electrical characterization of the metal-oxide semiconductor (MOS) devices. The analysis reveals that a decrease in the capacitance for high voltages and the errors faced during the electrical measurements lead to the nonabrupt layers.

In this work, the effects of Ag addition on phase transitions, microstructure and solder/copper interfaces of Sn99.1−xCu0.9Agx alloys were studied using differential scanning calorimetry, X-ray diffractometry, electron scanning microscopy and energy-dispersive X-ray spectroscopy. The results showed that the addition of Ag to the Sn99.1Cu0.9 alloy changes the thermal behavior of the melting and solidification points of studied alloys. The presence of silver also induced the formation of the Ag3Sn phase and decreased the amount of the Cu6Sn5 compound. [ABSTRACT FROM AUTHOR]

Copyright of Tecné, Episteme y Didaxis is the property of Universidad Pedaggica Nacional and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

1 - Coastal lagoons show great fragility and vulnerability to the anthropogenic pressure. The understanding of physical, chemical, geological characteristics and ecological dynamics of lagoons is fundamental for planning the implementation of coastal management strategies in these ecosystems. The intrinsically high variability of phytoplankton communities in transitional environments should be taken into account not only because of phytoplankton ecological importance, but also because of the implications for environmental management. 2 - The aim of this study is a general description of the phytoplankton community in three coastal lagoons situated in the Rio Grande do Norte region, at the Northeast of Brazil. 3 - For the three lagoons, a total of 124 phytoplankton taxa were identified. In terms of species richness, diatoms were the largest group with 92 identified taxa belonging to 46 genera. At the class level, Bacillariophyceae recorded 39 taxa belonging to 18 genera; Coscinodiscophyceae recorded 39 taxa belonging to 21 genera and Fragilariophyceae recorded 14 taxa belonging to 7 genera. The group of the dinoflagellates recorded 15 taxa belonging to 6 genera and the Cyanophyceae was represented by 8 taxa belonging to 5 genera, including Trichodesmium erythraeum, a taxon related to toxic blooms. [ABSTRACT FROM AUTHOR]

In the oil exploitation, produced fluids are composed of oil, gas, water and sand (depending on the reservoir location). The presence of sand in flow oil leads to several industrial problems for example: erosion and accumulation in valves and pipeline. Thus, it is necessary to stop production for manual cleaning of equipments and pipes. These facts have attracted attention of academic and industrial areas, enabling the appearing of new technologies or improvement of the water/oil/sand separation process. One equipment that has been used to promote phase separation is the hydrocyclone due to high performance of separation and required low cost to installation and maintenance. In this sense, the purpose of this work is to study numerically the effect of geometric parameters (vortex finder diameter) of the hydrocyclone and sand concentration on the inlet fluid separation process. A numerical solution of the governing equations was obtained by the ANSYS CFX-11 commercial code. Results of the streamlines, pressure drop and separation efficiency on the hydrocyclone are presented and analyzed. It was observed that the particles concentration and geometry affect the separation efficiency of the hydrocyclone. [ABSTRACT FROM AUTHOR]

The objective of this study was to analyze the genetic variability generated from two-way, four-way, and eight-way hybridizations in soybean, derived from parental lines contrasting in resistance to cyst nematode and powdery mildew. We assessed F2 populations using Simple Sequence Repeat (SSR) molecular markers located within the 50 cM region surrounding the Rmd (powdery mildew) and Rhg1 (cyst nematode) resistance genes. All markers were nonsignificant by chi-square test (P > 0.05), indicating that observed values align with the expected genotypic inheritance ratio in F2 populations (1:2:1). Lower polymorphism observed among parents explained the reduced recombination frequency in these populations. A higher mean crossover rate was observed in G4 (4.00) within linkage group G, and J8 (2.91) within linkage group J. In terms of the number of generations needed to form each population, crossover rates of 2.02 and 0.97 were found for G2 and J8, respectively. Recombination between alleles was present in some populations. Crosses involving a greater number of parents exhibited a higher frequency of crossovers, which positively impacts genetic variability. Therefore, the inclusion of more than two parents in hybridizations is recommended to enhance crossover frequency and genetic diversity. These findings provide valuable insights for breeding programs aiming to improve resistance in soybean, indicating that multi-parental crosses can be a strategic approach to increase genetic diversity and resilience against pathogens.

Portulaca umbraticola, commonly known as "Eleven o'clock", is a popular ornamental plant in Brazil, but its potential as a non-conventional food source remains underexplored. Assessing its genetic and cytogenetic diversity is crucial for breeding and selecting optimal accessions. In this study, we analyzed the genetic diversity of P. umbraticola using RAPD markers and chromosomal traits in 20 accessions. We also compared them with P. oleracea to identify potential interspecific hybrids. Accessions were collected from Brazil and cultivated in 3L pots with commercial substrate. Controlled crosses and self-fertilizations were conducted in a greenhouse, followed by cytogenetic analyses. All amplified bands showed polymorphism among 18 accessions, indicating 100% polymorphism. The species displayed considerable dissimilarity, with all 20 accessions showing 2n = 18 chromosomes, while P. oleracea had 2n = 52 chromosomes. P. umbraticola exhibited allogamous reproduction tendencies and self-incompatibility, precluding self-fertilization. Analysis suggests that crosses between accessions 12 and 16 are recommended due to their substantial genetic distance. In conclusion, P. umbraticola and P. oleracea differ in chromosome numbers, and P. umbraticola shows allogamous reproduction with self-incompatibility.

Contaminant levels are lower in Antarctica than elsewhere in the world because of its low anthropogenic activities. However, the northern region of the Antarctic Peninsula, is close to South America and experiences the greatest anthropogenic pressure in Antarctica. Here, we investigated, in two Antarctic Peninsula islands, intra and interspecific factors that influence the concentrations of 17 trace elements (TEs) in blood and feathers of three penguin species breeding sympatrically in relation to their trophic ecology assessed via a stable isotopic approach (C, N and S). Geographical location, foraging zone (δ 13 C and δ 34 S) and diet influences the interspecific difference, and sex and maturity stage diet influence the intraspecific difference of Pygoscelis penguins. Penguins from Livingston showed higher values (mean, ng. g -1 , dry weight - dw) of Zn (103), Mn (0.3), and Fe (95) than those from King George Island (Zn: 80, Mn: 1.9, and Fe: 11). Gender-related differences were observed, as males showed significantly higher values (mean, ng. g -1 , dw) of Rb (3.4) and δ 15 N in blood of gentoo, and Ca (1344) in Adélie feathers. Chicks of gentoo and Adélie presented higher Zn, Mg, Ca, and Sr and lower 13 C values in blood than adults. The highest concentrations (mean, ng. g -1 , dw) of Cd (0.2) and Cu (26), and the lowest δ 15 N values were found in chinstrap. Geographical, intraspecific (i.e., ontogenetic and gender-related) and interspecific differences in feeding seemed to have influenced TE and stable isotope values in these animals. The TE bioaccumulation by penguins may have also been influenced by natural enrichment in environmental levels of these elements, which seems to be the case for Fe, Zn, and Mn. However, the high level of some of the TEs (Mn, Cd, and Cr) may reflect the increase of local and global human activities., (Copyright © 2021 Elsevier Ltd. All rights reserved.)