“Leviana!”: desvendando a formação de duas redes de RTs durante os debates entre presidenciáveis em 2014

Esse artigo analisa a formação de duas redes sociotécnicas de retweets (RTs) coletadas com base no uso do termo “leviana” no Twitter a partir da transmissão televisiva de dois debates entre presidenciáveis em 2014. Apoiamo-nos principalmente na Teoria Ator-Rede e na Cartografia de Controvérsias para descrever os rastros deixados pelos actantes e compreender os debates propostos pelos atores nos minutos seguintes ao uso do termo pelo candidato Aécio Neves. Ressaltando a importância da análise da formação dessas redes ao longo do tempo, procuramos identificar as diferenças nas dinâmicas de associação das duas redes

Endodontic Output in Public Healthcare under Different Instrumentation Techniques: A Quantitative and Qualitative Study

Objective: To evaluate output of endodontic in oral public healthcare by analyzing differences in instrumentation techniques, quantitative and qualitatively. Material and Methods: Endodontic services were differentiated by instrumentation techniques: hand techniques with stainless steel instruments (SS) or rotary using NiTi rotary instruments. Secondary data on the productivity of 2011 were obtained from the information system. Student’s t and Mann-Whitney tests were used. Qualitative data were based on semi-structured interviews, direct observation and field diary. Results: Service I employed SS hand techniques, service II used both techniques, while NiTi rotary system was used in service III. Statistically significant differences were observed in total endodontic productivity, with I presenting more productive results than II (p=0.001) and III (p=0.009); III presenting more productive results than II (p<0.001). Comparisons of endodontic treatment types revealed that I performed more multiradicular tooth treatments than did II and III (p=0.005), and III performed more treatments on biradicular teeth than did I and II (p=0.002). Qualitative analyses were divided into themes: “perceptions of the service” and “perceptions of the employed instrument”. Conclusion: Professional experience and high productivity per hour can be a differential; the use of rotary instrumentation can be useful in solving unmet demands. Perception of endodontists showed that chosen endodontic technique influenced job satisfaction and lack of integrality of the treatment is a problem in secondary care

Ator-rede versus Análise de Redes versus Redes Digitais: falamos das mesmas redes?

Este artigo discute diferenças e afinidades entre três tipos de rede (Ator-Rede, Análise de Redes e Redes Digitais) importantes para o Digital STS.2 Nas últimas décadas, a colonização de pesquisas em STS foi lenta e gradual. Ela se inicia com a Teoria Ator-Rede (TAR), que oferece um conjunto de noções para descrever a construção de fenômenos sociotécnicos. Com o advento da Análise de Redes, estudiosos incorporam técnicas de investigação e visualização desenvolvidas pela Análise de Redes Sociais (ARS) e pela Cientometria aos estudos em STS. Com o crescente uso de recursos computacionais pelos STS, estudiosos atentam para as Redes Digitais como modo de rastrear a vida coletiva. Muitos pesquisadores tentaram relacionar esses três movimentos aos métodos digitais, ao apostarem que a TAR pode ser operacionalizada por meio da Análise de Redes, graças aos dados providos pelas Redes Digitais. No entanto, além da homonímia presente na palavra “rede”, que caracteriza as três abordagens mencionadas, há poucas evidências que comprovam a continuidade entre esses três tipos de rede. Falamos das mesmas redes

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Rarity of monodominance in hyperdiverse Amazonian forests.

Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the trees ≥ 10 cm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors

Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology

In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics

Unraveling Amazon tree community assembly using Maximum Information Entropy: a quantitative analysis of tropical forest ecology

In a time of rapid global change, the question of what determines patterns in species abundance distribution remains a priority for understanding the complex dynamics of ecosystems. The constrained maximization of information entropy provides a framework for the understanding of such complex systems dynamics by a quantitative analysis of important constraints via predictions using least biased probability distributions. We apply it to over two thousand hectares of Amazonian tree inventories across seven forest types and thirteen functional traits, representing major global axes of plant strategies. Results show that constraints formed by regional relative abundances of genera explain eight times more of local relative abundances than constraints based on directional selection for specific functional traits, although the latter does show clear signals of environmental dependency. These results provide a quantitative insight by inference from large-scale data using cross-disciplinary methods, furthering our understanding of ecological dynamics

Mapping density, diversity and species-richness of the Amazon tree flora

Using 2.046 botanically-inventoried tree plots across the largest tropical forest on Earth, we mapped tree species-diversity and tree species-richness at 0.1-degree resolution, and investigated drivers for diversity and richness. Using only location, stratified by forest type, as predictor, our spatial model, to the best of our knowledge, provides the most accurate map of tree diversity in Amazonia to date, explaining approximately 70% of the tree diversity and species-richness. Large soil-forest combinations determine a significant percentage of the variation in tree species-richness and tree alpha-diversity in Amazonian forest-plots. We suggest that the size and fragmentation of these systems drive their large-scale diversity patterns and hence local diversity. A model not using location but cumulative water deficit, tree density, and temperature seasonality explains 47% of the tree species-richness in the terra-firme forest in Amazonia. Over large areas across Amazonia, residuals of this relationship are small and poorly spatially structured, suggesting that much of the residual variation may be local. The Guyana Shield area has consistently negative residuals, showing that this area has lower tree species-richness than expected by our models. We provide extensive plot meta-data, including tree density, tree alpha-diversity and tree species-richness results and gridded maps at 0.1-degree resolution