Abstract The flotation mechanism of galena with xanthate as the collector is generally explained based on the mixed potential of the pulp, in which an anodic electron transfer reaction from the collector to the mineral is combined with an O2 cathodic reduction. Sodium sulphide, often used as a mineral activator, strongly influences the pulp's mixed potential, and depending on the dosage applied, it can become a galena depressor reagent. In this way, the current study assesses galena flotability in the absence of collector, as well as in the presence of the collector potassium amyl xanthate (PAX) and sodium sulphide. The effect of an extremely cathodic potential was also studied through the addition of hydrogen peroxide. In addition, the effect of different stages in the oxidation of the galena surface on the flotability was investigated. Moreover, the zeta potential was measured and contact angle (wettability) tests were carried out. The contact angle measurements were taken for a distilled water, PAX solution and for a mixture of PAX and sodium sulphide solution on the oxidized and non-oxidized surface of galena. All the results showed that galena could be floated in all the PAX concentrations tested. It was observed that a moderate oxidation in the galena surface may contribute to an improvement of its flotation with PAX. However, extremely anodic and cathodic potentials cause flotability close to zero. The zeta potential results showed that sodium sulphide affected the interaction between PAX and galena. The measurements of the contact angle corroborated the results obtained in the microflotation tests. pulp O reduction activator pulps s applied reagent way (PAX peroxide investigated Moreover wettability (wettability out water nonoxidized non tested However zero

Resumo O objetivo deste artigo é compreender como os sentimentos e as emoções de homens contribuem para o enquadramento da doença Covid-19 no Brasil. Estudo sócio-histórico, qualitativo, realizado com 200 homens residentes no Brasil, mediante pesquisa online em plataforma digital. Os dados apreendidos foram analisados pelo método do Discurso do Sujeito Coletivo à luz do referencial de doença epidêmica proposto por Charles Rosemberg. Prevaleceram sentimentos negativos e ansiedade como consequência do conhecimento acerca do crescente número de hospitalizados e mortos pela pandemia veiculada nos noticiários. Para os homens, o otimismo é necessário para encorajar atitudes com responsabilidade e confiar de que a crise será superada. Na sequência os homens apresentam um conjunto de atitudes e comportamentos para o enfrentamento da pandemia. E, a aceitação sinaliza a emergência do quarto ato dramatúrgico do enquadramento da Covid-19. Os sentimentos e as emoções de homens, no presente contexto histórico, atravessam três dos quatro atos de enquadramento da Covid-19 no Brasil.

Abstract Objective: to understand how men’s feelings and emotions contribute to the Covid-19 framing in Brazil. Method: Asocial-historical, qualitative study, carried out with 200 men resident in Brazil, through online search on digital platform.The grasped data were analyzed by the Collective Subject Discourse method in the light of the reference of epidemic disease proposed by Charles Rosemberg. Results: Negative feelings and anxiety prevailed due to the knowledge about the growing number of hospitalized patients and deaths from the pandemic conveyed in the news. For men, the optimism is necessary to encourage attitudes with responsibility and trust that the crisis will be overcome.Subsequently, men present a set of attitudes and behaviors for coping with the pandemic.Moreover,the acceptance signals the emergence of the fourth dramaturgical act of the Covid-19framing. Conclusion: Men’s feelings and emotions, in this historic context, pervade three of the four acts of the Covid-19 framingin Brazil.

Resumo O objetivo deste artigo é compreender como os sentimentos e as emoções de homens contribuem para o enquadramento da doença Covid-19 no Brasil. Estudo sócio-histórico, qualitativo, realizado com 200 homens residentes no Brasil, mediante pesquisa online em plataforma digital. Os dados apreendidos foram analisados pelo método do Discurso do Sujeito Coletivo à luz do referencial de doença epidêmica proposto por Charles Rosemberg. Prevaleceram sentimentos negativos e ansiedade como consequência do conhecimento acerca do crescente número de hospitalizados e mortos pela pandemia veiculada nos noticiários. Para os homens, o otimismo é necessário para encorajar atitudes com responsabilidade e confiar de que a crise será superada. Na sequência os homens apresentam um conjunto de atitudes e comportamentos para o enfrentamento da pandemia. E, a aceitação sinaliza a emergência do quarto ato dramatúrgico do enquadramento da Covid-19. Os sentimentos e as emoções de homens, no presente contexto histórico, atravessam três dos quatro atos de enquadramento da Covid-19 no Brasil.

Abstract Objective: to understand how men’s feelings and emotions contribute to the Covid-19 framing in Brazil. Method: Asocial-historical, qualitative study, carried out with 200 men resident in Brazil, through online search on digital platform.The grasped data were analyzed by the Collective Subject Discourse method in the light of the reference of epidemic disease proposed by Charles Rosemberg. Results: Negative feelings and anxiety prevailed due to the knowledge about the growing number of hospitalized patients and deaths from the pandemic conveyed in the news. For men, the optimism is necessary to encourage attitudes with responsibility and trust that the crisis will be overcome.Subsequently, men present a set of attitudes and behaviors for coping with the pandemic.Moreover,the acceptance signals the emergence of the fourth dramaturgical act of the Covid-19framing. Conclusion: Men’s feelings and emotions, in this historic context, pervade three of the four acts of the Covid-19 framingin Brazil.

ABSTRACT The kale is a brassica, this vegetable presents importance on nutritional and economic patterns. The present study aimed to evaluate the effect of different substrates, trays and protected environment in the formation of kale seedlings. The experiment was conducted in two greenhouses located at the State University of Mato Grosso do Sul - MS. The first environment consisted of an agricultural greenhouse with polyethylene film cover, while the second was an agricultural nursery with monofilament screen and mesh to offer 50% of shading. In each protected environment were used 72 and 128 cells tray and six different compositions of substrates with organic material based on cassava branches (CB) and cattle manure (CM): 1) 100% CM; 2) 20% CM + 80% CB; 3) 40% CB + 60% CM; 4) 60% CB + 40% CM; 5) 80% CB + 20% and CM; 6) 100% CB. The seedlings were evaluated according to the parameters: dry mass of seedlings, stem diameter and plant height. The agricultural nursery was the most suitable for the formation of kale seedlings, with 72 cells tray and the substrate composed of organic matter with 20% of cassava branches and 80% of cattle manure.