5 research outputs found
ELON LAGES LIMA E O SEU PRIMEIRO LIVRO: TOPOLOGIA DOS ESPAÇOS MÉTRICOS
O Brasil vem conquistando cada vez mais espaço na Matemática mundial. Tal reconhecimento se deu graças à grande quantidade de matemáticos de sucesso que o nosso país tem revelado ao longo das décadas. Entre todos eles, destaca-se Elon Lages Lima (1929-2017), que se consolidou como um dos maiores matemáticos brasileiros. O trabalho a seguir trata-se de um estudo sobre a vida e a carreira de Elon, discutindo também sua atuação como escritor, com foco no livro Topologia dos Espaços Métricos, que ao longo do tempo foi transformado no livro Espaços Métricos e rendeu ao autor o Prêmio Jabuti, outorgado pela Câmara Brasileira do Livro. O objetivo desta pesquisa é apresentar um levantamento da carreira de Elon Lages Lima e suas principais contribuições para a Matemática, como professor, pesquisador e escritor. Além disso, compreender o livro Topologia dos Espaços Métricos, de sua autoria, por meio de uma breve discussão sobre a metodologia usada pra explanar o assunto. A pesquisa é do tipo descritiva, por meio de um levantamento bibliográfico e documental. Após a análise do livro, é notável o cuidado do autor em usar uma linguagem mais acessível para explanar os conteúdos, sem abrir mão do rigor necessário para um bom aproveitamento do estudo. Sua metodologia mostra ainda o desejo de despertar o interesse e a curiosidade no leitor, usando táticas para fazê-lo participar das demonstrações e demais operações contidas nos capítulos. Constata-se, com esse estudo, a grande importância de Elon para a Matemática brasileira e que sua atuação na área rendeu enormes avanços para o ensino e a pesquisa em Matemática. Dessa forma, espera-se incentivar o aprofundamento de pesquisas sobre a carreira e as obras de Elon Lages Lima e contribuir para a disseminação dos ensinamentos desse matemático para aqueles interessados no assunto
Electrocardiographic Pattern of Agoutis (Dasyprocta prymnolopha) Chemically Contained by the Association of Ketamine and Xylazine
Background: The agouti (Dasyprocta prymnolopha, Wagler, 1831) is an existing wild rodent in almost all of Brazil, used as a biological model in several scientific studies. Veterinary cardiology has showed great advances in the diagnostic area due to the possibility of cardiac evaluation by non-invasive methods. For the practice of scientific or handling procedures in wild animals, chemical containment is essential. Thus, it is important to know the effect of anesthetic protocols on the cardiovascular system, observed through complementary tests, such as the electrocardiogram. The objective of this study was to describe the computerized electrocardiographic tracing of agoutis chemically contained by the association of Ketamine and Xylazine.Materials, Methods & Results: Eighteen male and female clinically healthy animals, aged among 2 years, submitted to digital electrocardiographic examination, were used. The device used to obtain the tracing was the veterinary electrocardiograph (Electrocardiogram Acquisition Module for Computer) - Brazilian Electronic Technology (TEB). The analysis was always made from derivation II (DII). Chemical containment was performed by the combination of Ketamine and Xylazine, intramuscularly. The results showed that the heart rate for males was on average 113.25 bpm, while for females the value of 124.60 bpm was observed, and there was no significant difference between the genders (P > 0.05). The mean weight of males was 2.31 kg and for females 2.28 kg; there was no statistical difference for this variable (P > 0.05). For the QRS duration of 46.14 ± 5.05 ms (males) and 44.66 ± 5.94 ms (females) and PR interval of 79.94 ± 12.01ms (males) and 84.29 ± 12.37ms (females), there was no statistical difference (P > 0.05). The amplitude of the R wave of 0.42 ± 0.31 mV (males) and 0.36 ± 0.22 mV (females) showed no statistical difference (P > 0.05). The T wave showed itself both negative (10 animals) and positive (8 animals), with amplitude measured at 0.24 ± 0.16 mV for males and 0.25 ± 0.10 mV for females (P > 0.05). The anesthetic protocol was well tolerated by the animals of this experiment, and there were no episodes of arrhythmias during the time of their monitoring.Discussion: Wild animals, in general, need chemical containment, with a view to reducing stress during scientific and handling procedures. The protocols established in this work can be used in future experiments which require a longer handling time. The values found for heart rate (HR) of anesthetized agoutis were lower than those for non-anesthetized agoutis, proving the influence of the stress during retention and the depressant cardiovascular effect of the anesthetic drug used. The electrocardiographic parameters and the tracing morphology of the agoutis were like the results found for anesthetized small rodents. The QT interval was higher in males than in females, justifying the fact that it could be influenced by variations in HR, which also showed superior results for males. Taking into consideration the morphological similarity between different individuals, the QT interval in anesthetized agoutis did not present significant differences between the genders, a characteristic also found in ferrets. The animals of this experiment were submitted to food fasting, a fact that contributed to a better standardization of the experiment, preventing alterations in the morphology of the QRS complex, which could lead to changes in the measurements
Comparative study by computed radiography, histology, and scanning electron microscopy of the articular cartilage of normal goats and in chronic infection with caprine arthritis-encephalitis virus
In the northeast of Brazil, caprine arthritis-encephalitis (CAE) is one of the key reasons for herd productivity decreasing that result in considerable economic losses. A comparative study was carried out using computed radiography (CR), histological analysis (HA), and scanning electronic microscopy (SEM) of the joints of CAE infected and normal goats. Humerus head surface of positive animals presented reduced joint space, increased bone density, and signs of degenerative joint disease (DJD). The carpal joint presented no morphological alterations in CR in any of the animals studied. Tarsus joint was the most affected, characterized by severe DJD, absence of joint space, increased periarticular soft tissue density, edema, and bone sclerosis. Histological analysis showed chronic tissue lesions, complete loss of the surface zone, absence of proteoglycans in the transition and radial zones and destruction of the cartilage surface in the CAE positive animals. Analysis by SEM showed ulcerated lesions with irregular and folded patterns on the joint surface that distinguished the limits between areas of normal and affected cartilage. The morphological study of the joints of normal and CAE positive goats deepened understanding of the alteration in the tissue bioarchitecture of the most affected joints. The SEM finding sustained previous histological reports, similar to those found for rheumatoid arthritis, suggesting that the goat infected with CAE can be considered as a potential model for research in this area.Contract grant sponsor: National Council for Scientific and Technological Development (CNPq)
Brazilian Flora 2020: Leveraging the power of a collaborative scientific network
International audienceThe shortage of reliable primary taxonomic data limits the description of biological taxa and the understanding of biodiversity patterns and processes, complicating biogeographical, ecological, and evolutionary studies. This deficit creates a significant taxonomic impediment to biodiversity research and conservation planning. The taxonomic impediment and the biodiversity crisis are widely recognized, highlighting the urgent need for reliable taxonomic data. Over the past decade, numerous countries worldwide have devoted considerable effort to Target 1 of the Global Strategy for Plant Conservation (GSPC), which called for the preparation of a working list of all known plant species by 2010 and an online world Flora by 2020. Brazil is a megadiverse country, home to more of the world's known plant species than any other country. Despite that, Flora Brasiliensis, concluded in 1906, was the last comprehensive treatment of the Brazilian flora. The lack of accurate estimates of the number of species of algae, fungi, and plants occurring in Brazil contributes to the prevailing taxonomic impediment and delays progress towards the GSPC targets. Over the past 12 years, a legion of taxonomists motivated to meet Target 1 of the GSPC, worked together to gather and integrate knowledge on the algal, plant, and fungal diversity of Brazil. Overall, a team of about 980 taxonomists joined efforts in a highly collaborative project that used cybertaxonomy to prepare an updated Flora of Brazil, showing the power of scientific collaboration to reach ambitious goals. This paper presents an overview of the Brazilian Flora 2020 and provides taxonomic and spatial updates on the algae, fungi, and plants found in one of the world's most biodiverse countries. We further identify collection gaps and summarize future goals that extend beyond 2020. Our results show that Brazil is home to 46,975 native species of algae, fungi, and plants, of which 19,669 are endemic to the country. The data compiled to date suggests that the Atlantic Rainforest might be the most diverse Brazilian domain for all plant groups except gymnosperms, which are most diverse in the Amazon. However, scientific knowledge of Brazilian diversity is still unequally distributed, with the Atlantic Rainforest and the Cerrado being the most intensively sampled and studied biomes in the country. In times of “scientific reductionism”, with botanical and mycological sciences suffering pervasive depreciation in recent decades, the first online Flora of Brazil 2020 significantly enhanced the quality and quantity of taxonomic data available for algae, fungi, and plants from Brazil. This project also made all the information freely available online, providing a firm foundation for future research and for the management, conservation, and sustainable use of the Brazilian funga and flora