Investigação e avaliação da toxicidade aguda dos agrotóxicos mais utilizados no cinturão verde da Grande Natal (RN, Brasil) para o peixe-zebra (Danio rerio Hamilton Buchanan, 1822, Teleostei, Cyprinidae

The objectives of this research were to investigate the agrotoxic most used in the Gramorezinho region in the green belt of Natal, and to evaluate the acute toxicity of these, based on the LC50-48h values estimated in tests for Danio rerio, internationally used as test organism. The acute toxicity tests were performed under laboratory conditions, according to standardized methods (ABNT/NBR/15088/04) for this species. The LC50-48h estimated to Tamaron BR was 352.89 mg.L-1, which characterizes that as practically non-toxic, according to toxicological classes cited by Zucker. For Decis 25EC, the LC50-48h estimated was 0.0004156 mg.L-1 (4.156 X 10-4 mg.L-1), which classifies it as highly toxic to this species

Investigação e avaliação da toxicidade aguda dos agrotóxicos mais utilizados no cinturão verde da Grande Natal (RN, Brasil) para o peixe-zebra (Danio rerio Hamilton Buchanan, 1822, Teleostei, Cyprinidae

The objectives of this research were to investigate the agrotoxic most used in the Gramorezinho region in the green belt of Natal, and to evaluate the acute toxicity of these, based on the LC50-48h values estimated in tests for Danio rerio, internationally used as test organism. The acute toxicity tests were performed under laboratory conditions, according to standardized methods (ABNT/NBR/15088/04) for this species. The LC50-48h estimated to Tamaron BR was 352.89 mg.L-1, which characterizes that as practically non-toxic, according to toxicological classes cited by Zucker. For Decis 25EC, the LC50-48h estimated was 0.0004156 mg.L-1 (4.156 X 10-4 mg.L-1), which classifies it as highly toxic to this species

Mariana , Pai contra mãe e O caso da vara : escravidão e chão histórico em Machado de Assis

Machado de Assis understood his time and brought his perception of Brazilian society in the 19th century, with its multiple aspects economy, politics, culture, amongst others - to the texts he wrote. Through the tensions lived in his novels and short stories, Machado displays Brazilian social reality and the changes it had been undergoing. Mariana and Pai contra mãe show the crisis of the slavery system, the relation of dependency, the treatment given to the captives and the lack of coherence of a country that intended to adopt Liberalism as an ideology, but which kept on living under the shadow of slavery and its consequences. A country where the priorities were given to the landlords, owners of slaves, in protection of their interests. O caso da vara tells about how the crias da casa little black girls who lived in the household and learned how to make spool embroidery were treated. What were the punishments for desobedience and how they were levelled out, how should be the behaviour of a child who lived as a social outcast. Thus, this paper aims at playing a game of mirrors between History and fiction. Not only to play it, but to analyze how Machado deals with the reflections of 19th century Brazil on his short stories