Sobre a definição do processo de simulação do comportamento mecânico da Aorta Torácica Ascendente

Segundo a Organização Mundial de Saúde as doenças cardiovasculares são uma das principais causas de morte da atualidade. Destas fazem partes os aneurismas da aorta torácica. Entre estes os mais comuns são os da aorta torácica ascendente, representando certa de 60% dos casos. Estes devem ser monitorizados e controlados, sendo que perante a sua rotura a probabilidade de morte é de até 94%. Atualmente, o método de decisão cirúrgica baseia-se somente na avaliação do diâmetro do aneurisma, sendo que quando este é superior a 5,5 cm é recomendada intervenção cirúrgica. Este método tem-se re- petidamente demonstrado falível, visto que existem consideráveis quantidades de casos em que se dá a rotura ou disseção do aneurisma antes da verificação deste critério. As- sim, surge a necessidade de implementar novos métodos de avaliação e análise de risco dos aneurismas. A necessidade de estudar melhor o aneurisma de forma a melhorar a qualidade de vida e taxa de sobrevivência de pacientes por ele afetados é uma grande motivação para o desenvolvimento deste projeto e dissertação. A presente dissertação insere-se num projeto multidisciplinar que tem como objetivo o desenvolvimento de um modelo robusto que permita determinar/prever o comportamento mecânico da artéria aorta, considerando a definição de intervalos de simulação. Assim, esta dissertação foca-se no estudo e criação de uma geometria e modelo de elementos finitos capaz de simular o comportamento mecânico da parede da artéria aorta ascendente, considerando a incerteza inerente aos processos de criação. Para tal foi implementado um método de análise de variabilidade do processo de obtenção da geometria a partir de exames médicos, onde se obtém uma métrica que permite comparar e quantificar a variabilidade do processo. Posteriormente foi desenvolvido e analisado um modelo de elementos finitos. A dissertação contém uma extensa pesquisa bibliográfica, que visa a construir uma base sólida para o desenvolvimento futuro do projeto no qual está incluída.According to the World Health Organization cardiovascular diseases are one of the main causes of death of the modern world. The thoracic aorta aneurysms are part of this group of diseases. The most common of these are the ascending thoracic aorta aneurysms, which represent 60% of the cases. These should be monitored and controlled because in case of rupture they present a rate of mortality up to 94%. Currently the method on which the decision is made upon relies only on the aneurysm diameter, being recomended surgical intervention when the diameter is above 5.5 cm. This metric has been continu- ously shown to be flawed as there is a considerable amount of cases (about 60%) in which the aneurysm ruptures before the diameter reaches 5.5 cm. Due to this there comes a necessity to come up with a new and better criteria fot the evaluation of aneurysms. The main motivation in the studying of this condition is the improvement of the quality of life and survival chance of pacients affected by it. This thesis is part of a multidisciplinary project which goal is to develop a robust model that is capable of predicting and deter- mine the mechanical behavior of the human ascending aorta, considering the definition of simulation intervals. This thesis focuses on the studying creation of a geometry and finite element model capable of simulating the mechanical behavior of the ascending aorta walls, considering the uncertainty inherent to the creation process. To this end an analysis method was implemented to determine the variability of the geometry creation process from medical exams, where the output is a metric that can compare and quantify the process variability. Then a finite element model was developde and analysed. This dissertation contains a extensive amount of research done with the goal of estabilishing a solid foundation for the future development of the project in with it is included

NEOTROPICAL ALIEN MAMMALS: a data set of occurrence and abundance of alien mammals in the Neotropics

Biological invasion is one of the main threats to native biodiversity. For a species to become invasive, it must be voluntarily or involuntarily introduced by humans into a nonnative habitat. Mammals were among first taxa to be introduced worldwide for game, meat, and labor, yet the number of species introduced in the Neotropics remains unknown. In this data set, we make available occurrence and abundance data on mammal species that (1) transposed a geographical barrier and (2) were voluntarily or involuntarily introduced by humans into the Neotropics. Our data set is composed of 73,738 historical and current georeferenced records on alien mammal species of which around 96% correspond to occurrence data on 77 species belonging to eight orders and 26 families. Data cover 26 continental countries in the Neotropics, ranging from Mexico and its frontier regions (southern Florida and coastal-central Florida in the southeast United States) to Argentina, Paraguay, Chile, and Uruguay, and the 13 countries of Caribbean islands. Our data set also includes neotropical species (e.g., Callithrix sp., Myocastor coypus, Nasua nasua) considered alien in particular areas of Neotropics. The most numerous species in terms of records are from Bos sp. (n = 37,782), Sus scrofa (n = 6,730), and Canis familiaris (n = 10,084); 17 species were represented by only one record (e.g., Syncerus caffer, Cervus timorensis, Cervus unicolor, Canis latrans). Primates have the highest number of species in the data set (n = 20 species), partly because of uncertainties regarding taxonomic identification of the genera Callithrix, which includes the species Callithrix aurita, Callithrix flaviceps, Callithrix geoffroyi, Callithrix jacchus, Callithrix kuhlii, Callithrix penicillata, and their hybrids. This unique data set will be a valuable source of information on invasion risk assessments, biodiversity redistribution and conservation-related research. There are no copyright restrictions. Please cite this data paper when using the data in publications. We also request that researchers and teachers inform us on how they are using the data

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved

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