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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]

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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]

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.)

Circular RNA (circRNA) is an unusual class of RNA-like structures composed by exonic and/or intronic sequences that are regulated by the backsplicing mechanism and by the spliceosome-mediated machinery. These circular transcripts tend to accumulate during aging in several human tissues, especially in the mammalian brain, and their expression is correlated with the occurrence of several human pathologies, including a broad spectrum of neurological disorders. Previous findings have also shown that circRNAs are significantly present in the neuronal tissue and are up-regulated during neurogenesis, with a significant number been derived from neural genes, suggesting these circular molecules are involved in the cellular and molecular phenotype of our brain. However, the complete biogenesis, the many types of circRNA molecules, and their involvement with neuronal phenotype and with the occurrence of pathologies are still a challenging avenue for researchers. In this updated review, we discuss the current findings of the biogenesis and the diversity of cirRNAs and their molecular involvement in neurological tissue phenotype. We also discuss how some circRNAs can act as sponge molecules, regulating the activity of microRNA expression over gene translation. Finally, we also show the correlation of altered circRNA expression in neurological disorders., (Copyright © 2020. Published by Elsevier Ltd.)

The ADAM (A Disintegrin And Metalloprotease) gene family encodes proteins with adhesion and proteolytic functions. ADAM proteins are associated with diseases like cancers. Twenty ADAM genes have been identified in humans. However, little is known about the evolution of the family. We analyzed the repertoire of ADAM genes in a vast number of eukaryotic genomes to clarify the main gene copy number expansions. For the first time, we provide compelling evidence that early-branching green algae (Mamiellophyceae) have ADAM genes, suggesting that they originated in the last common ancestor of eukaryotes, before the split of plants, fungi and animals. The ADAM family expanded in early metazoans, with the most significative gene expansion happening during the first steps of vertebrate evolution. We concluded that most of mammal ADAM diversity can be explained by gene duplications in early bone fish. Our data suggest that ADAM genes were lost early in green plant evolution., (Copyright © 2020 Elsevier Inc. All rights reserved.)

CD4(+) Foxp3(+) regulatory T (Treg) cells are necessary for the maintenance of self-tolerance and T-cell homeostasis. This population is kept at stable frequencies in secondary lymphoid organs for the majority of the lifetime, despite permanent thymic emigration or in the face of thymic involution. Continuous competition is expected to occur between recently thymus-emigrated and resident Treg cells (either natural or post-thymically induced). In the present work, we analysed the renewal dynamics of Treg cells compared with CD4(+) Foxp3- conventional T cells (Tconv), using protocols of single or successive T-cell transfers into syngeneic euthymic or lymphopenic (nu/nu or RAG2(-/-)) mice, respectively. Our results show a higher turnover for Treg cells in the peripheral compartment, compared with Tconv cells, when B cell-sufficient euthymic or nude hosts are studied. This increased renewal within the Treg pool, shown by the greater replacement of resident Treg cells by donor counterparts, correlates with augmented rates of proliferation and is not modified following temporary environmental perturbations induced by inflammatory state or microbiota alterations. Notably, the preferential substitution of Treg lymphocytes was not observed in RAG2(-/-) hosts. We showed that limited B-cell replenishment in the RAG2(-/-) hosts decisively contributed to the altered peripheral T-cell homeostasis. Accordingly, weekly transfers of B cells to RAG2(-/-) hosts rescued the preferential substitution of Treg lymphocytes. Our study discloses a new aspect of T-cell homeostasis that depends on the presence of B lymphocytes to regulate the relative incorporation of recently arrived Treg and Tconv cells in the peripheral compartment., (© 2015 John Wiley & Sons Ltd.)

Background: Pharmacological treatments have been successfully used to treat Generalized Anxiety Disorder (GAD). The mainstay for the pharmacological treatment of GAD in past decades has been the use of benzodiazepine and non benzodiazepine anxiolytics. Data emerging over the last two decades have shown that antidepressants may be equally effective to anxiolytics for treating GAD. The use of antidepressants for treating GAD may be advantageous, due to the fact that GAD presents a high co morbidity ratio with major depressive disorder (62%) and dysthymia (37%)., Objectives: To assess the efficacy and acceptability of antidepressants for treating generalized anxiety disorder., Search Strategy: Cochrane Collaboration Depression, Anxiety and Neurosis Controlled Trials Register - CCDANCTR (up to May 2002), Anxiety Neurosis (up to May 2002) and Cochrane Controlled Trials Register (CENTRAL/CCTR) (up to May 2002), MEDLINE (1966 to May 2002), LILACS (1982 to May 2002); reference searching; personal communication; conference abstracts and book chapters on the treatment of generalized anxiety disorder., Selection Criteria: Randomised controlled trials were included. Exclusion criteria were: non randomised studies; studies which included patients with generalized anxiety disorder and another Axis I co-morbidity., Data Collection and Analysis: The data from studies were extracted independently by two reviewers and relative risks, weighted mean difference and number needed to treat were estimated. People who died or dropped out were regarded as having had no improvement., Main Results: Antidepressants (imipramine, venlafaxine and paroxetine) were found to be superior to placebo in treating GAD. The calculated NNT for antidepressants in GAD is 5.15. Dropout rates did not differ between antidepressants. Only one study presented data on imipramine and trazodone. Imipramine was chosen as the reference drug and, therefore, data on trazodone could not be included in the meta analysis. Only one study was conducted among children and adolescents (Rynn 2001). The latter study showed very promising results of sertraline in children and adolescents with GAD, which warrants its replication in larger samples., Reviewer's Conclusions: The available evidence suggests that antidepressants are superior to placebo in treating GAD. There is evidence from one trial suggesting that paroxetine and imipramine have a similar efficacy and tolerability. There is also evidence from placebo-controlled trials suggesting that these drugs are well tolerated by GAD patients. Further trials of antidepressants for GAD will help to demonstrate which antidepressants should be used for which patients.