The Surface Texturing of Monocrystalline Silicon with NH4OH and Ion Implantation for Applications in Solar Cells Compatible with CMOS Technology

AbstractThis work presents the development of photovoltaic cells based on p+/n junction in Si substrates, aimed at compatibility with fabrication processes with CMOS technology. The compatible processes, which are developed in this study, are the techniques:i) Si surface texturing, with the textured surface reflection of 15% obtained by the formation of micro-pyramids (heights between 3 and 7μm) using NH4OH (ammonium hydroxide) alkaline solution, which is free of undesirable contamination by Na+ and K+ ions, when NaOH and KOH traditional solutions are used, respectively, and ii) of the ECR-CVD (ElectronCyclotron Resonance - Chemical Vapor Deposition) deposition of SiNx (silicon nitride) anti-reflective coating (ARC), which is carried out at room temperature and can be performed after the end of cell fabrication without damage on metallic tracks and without variation of p+/n junction depth. The ARC coating characterization presented that the silicon nitride has a refractive index of 1.92 and a minimum reflectance of 1.03%, which is an excellent result for application in solar (or photovoltaic) cells. For the formation of the pn junction was used ion implantation process with 11B+, E=20KeV, dose of 1x1015cm2 and four rotations of 90° to get uniformity on texturized surfaces

Morphology of Gambierdiscus excentricus (Dinophyceae) with emphasis on sulcal plates

Gambierdiscus excentricus is an epibenthic dinoflagellate able to produce ciguatoxin and maitotoxin-like compounds that are responsible for ciguatera fish poisoning. Morphological descriptions and molecular characterization of two G. excentricus strains isolated from Brazil and maintained in culture were provided. The most complete description of the morphology of the sulcal region of Gambierdiscus based on light and scanning electron microscopy was presented. The sulcal area morphology and nomenclature used by different authors to name the sulcal plates in Gambierdiscus were reviewed. Two small sulcal plates (S.m.a. and S.m.p.) were shown for the first time. Phylogenetic trees based on D1–D3 and D8–D10 large subunits of ribosomal RNA gene sequences showed that the strains of G. excentricus from Brazil clustered with strains of G. excentricus isolated from its type locality, the Canary Islands. Both phylogenetic trees reconstructed the same relationships among all the formally described Gambierdiscus species and Gambierdiscus sp. ribotype 2 and Gambierdiscus sp. type 2.Versión del editor2,080

Human liver memory CD8(+) T cells use autophagy for tissue residence

Tissue-resident memory T cells have critical roles in long-term pathogen and tumor immune surveillance in the liver. We investigate the role of autophagy in equipping human memory T cells to acquire tissue residence and maintain functionality in the immunosuppressive liver environment. By performing ex vivo staining of freshly isolated cells from human liver tissue, we find that an increased rate of basal autophagy is a hallmark of intrahepatic lymphocytes, particularly liver-resident CD8(+) T cells. CD8(+) T cells with increased autophagy are those best able to proliferate and mediate cytotoxicity and cytokine production. Conversely, blocking autophagy induction results in the accumulation of depolarized mitochondria, a feature of exhausted T cells. Primary hepatic stellate cells or the prototypic hepatic cytokine interleukin (IL)-15 induce autophagy in parallel with tissue-homing/retention markers. Inhibition of T cell autophagy abrogates tissue-residence programming. Thus, upregulation of autophagy adapts CD8(+) T cells to combat mitochondrial depolarization, optimize functionality, and acquire tissue residence

A FORMAÇÃO NO TEMPO E NO ESPAÇO DA INTERNET DAS COISAS

RESUMO: A Internet das Coisas tem revolucionado a forma de produção e reprodução do conhecimento. Trata-se de um tipo de interface comunicacional entre humanos, máquinas e objetos que, ao fundir os mundos material e informacional, suscita as seguintes questões: (1) a possibilidade de obtenção imediata de quaisquer informações implicaria na produção do pensamento crítico, em uma espécie de relação causa-efeito?; (2) se é possível acessar as informações em quaisquer tempo e espaço, quais seriam as transformações decorrentes no processo formativo dos alunos e dos professores? Justamente essas questões motivaram os autores do artigo a elaborar o seguinte objetivo: refletir criticamente sobre a revitalização do conceito de formação (Bildung ) na temporalidade e localidade da Internet das Coisas