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Strategies of a light-demanding emergent tree to thrive in a neotropical seasonal forest with alternating light or water shortage
No full textIn tropical seasonal semideciduous forests (TSSF), plants face alternating drought or light shortage in dry and rainy seasons, respectively. To understand how emergent trees deal with seasonality across ontogeny, we sampled all individuals of the widely distributed species Astronium graveolens Jacq. (Anacardiaceae) in 100 random plots (10 m × 10 m each) in a TSSF fragment in southeastern Brazil, and conducted greenhouse experiments on photosynthetic and gas exchange responses to drought and shade. We recognized six ontogenetic stages by external structures, and analyzed height-diameter allometry and biomechanical design across ontogeny. Trade-offs were inferred in early life (increasing height, diameter, or leaf number implied smaller leaves; height growth implied less leaf production) and in mid-life (height or diameter growth implied no branch production). The population did not adjust to a biomechanical model, implying a growth pathway between pioneer and canopy species. All stages were biomechanically stable, and the safety factor decreased with height. In adult trees, the asymptotic height indicated water limitation. In young plants, drought did not affect gas exchange. Light–shadow experiments suggested a trade-off between shoot and root growth. Our results indicate how a light-demanding emergent tree balances trade-offs across ontogeny to deal with seasonally alternating water or light shortage3920721
The selective florivory of Erioscelis emarginata matches its role as a pollinator of Philodendron
No full textFlowers commonly face the dilemma of needing to be attractive to pollinators but unattractive to nectar robbers or florivores. When the pollinator has chewing mouthparts, there is also a considerable risk of the pollinator consuming the flowers. Scant field records indicate that the florivorous beetle Erioscelis emarginata (Mannerheim) (Coleoptera: Scarabaeidae: Cyclocephalini), which pollinates Philodendron spp., feeds selectively on the sterile staminate flowers. Here, the hypothesis was tested that E. emarginata prefers sterile staminate flowers of Philodendron bipinnatifidum Schott and Philodendron melinonii Brongn. ex Regel (Araceae) over fertile flowers. This study also examined whether such a preference exists regardless of the proportion of fertile vs. sterile flowers in each Philodendron species. Analysis of nutritional and defensive compounds plus scanning electron microscopy on each flower type were performed. The feeding preference of florivores for either P. bipinnatifidum or P. melinonii was also examined. In both species, sterile flowers were significantly more consumed than fertile ones. The sterile zone of P. bipinnatifidum was significantly larger than that of P. melinonii, and sterile staminate flowers of both plants were consumed at similar rates. Calcium oxalate was markedly low in sterile flowers, which also presented smaller papillae than the other flowers. This study presents evidence that the balance between pollination and florivory has most likely evolved through a strong feeding preference for less‐defended sterile flowers regardless of the size of the sterile zone1563290300CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO CARLOS CHAGAS FILHO DE AMPARO À PESQUISA DO ESTADO DO RIO DE JANEIRO - FAPERJFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2009/304473‐0; 480264/2010‐4E26/110.355/20122011/17708‐
Crown fracture: Failure load, stress distribution, and fractographic analysis
No full textStatement of problem. The outcomes from load-to-failure tests may not be applicable to clinical situations. Purpose. The purpose of this study was to critically evaluate the efficacy of load-to-failure tests in the investigation of the fracture load and pattern of metal-free crowns. Material and methods. Four groups were formed from 128 bovine roots restored with metal posts, resin cores, and feldspathic, leucite, or lithium disilicate ceramic systems or polymer crowns. Each group was divided into 4 (n=8) according to the cement: zinc phosphate, self-adhesive resin, autopolymerizing resin, and glass ionomer. Mean fracture loads from compressive tests were submitted to ANOVA and Tukey HSD test. Finite element and fractographic analyses were performed and associated with the fracture load and pattern. Results. Significantly higher fracture load values were obtained for the lithium disilicate ceramic, but finite element and fractographic analyses showed that the cement effect could not be determined. The finite element analysis showed the cement likely affected the fracture pattern, confirmed that stresses in the cements were little affected by the crown materials, and found that the stressed conditions were lowest in the lithium disilicate compared with other crowns for all cement combinations. The stressed conditions in the crowns depended more on the adhesive properties than on the elastic modulus of the cement materials. The level of the stressed condition in the crowns at the occlusal surface was about the same or higher than along their cement interface, consistent with the fractography, which indicated fractures starting at the load point. Higher stress levels in the crowns corresponded with a lower number of catastrophic fractures, and higher stresses in the cements seemed to reduce the number of catastrophic fracture patterns. The highest stressed conditions occurred along the occlusal surface for crown materials with a low elastic modulus or in combination with adhesive cements. Conclusions. The method used was not appropriate either for investigating the crowns' fracture load and pattern or for stating the role of the cements within the crown-cement-tooth interaction1143447455FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE MINAS GERAIS - FAPEMIGsem informaçã
A framework for designing and evaluating solar flare forecasting systems
No full textDisturbances in space weather can negatively affect several fields, including aviation and aerospace, satellites, oil and gas industries, and electrical systems, leading to economic and commercial losses. Solar flares are the most significant events that can affect the Earth’s atmosphere, thus leading researchers to drive efforts on their forecasting. The related literature is comprehensive and holds several systems proposed for flare forecasting. However, most techniques are tailor-made and designed for specific purposes, not allowing researchers to customize them in case of changes in data input or in the prediction algorithm. This paper proposes a framework to design, train, and evaluate flare prediction systems which present promising results. Our proposed framework involves model and feature selection, randomized hyperparameters optimization, data resampling, and evaluation under operational settings. Compared to baseline predictions, our framework generated some proof-of-concept models with positive recalls between 0.70 and 0.75 for forecasting ≥M class flares up to 96 h ahead while keeping the area under the ROC curve score at high levels495333323349COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESNão te
A new solution based on inter-vehicle communication to reduce traffic jam in highway environment
No full textTraffic congestion is an urban mobility problem, which generates stress to drivers and economic losses. In 2012, greenhouse gas emissions from transportation accounted for about 28% of total U.S. greenhouse gas emissions. Intelligent transportation systems can assist in the identification and reduction of vehicular traffic congestion. In this context, this work proposes an intelligent traffic information system based on intervehicle communication to avoid vehicle traffic congestion. The main goal of the proposed solution is to decrease CO2 emissions, the average trip time and fuel consumption by avoiding congested roads. Simulation results show that our proposed solution can reduce the average trip time, and the overall CO2 emission and fuel consumption. In particular, the trip time was decreased approximately 86%, the fuel consumption 40% and the CO2 emission 55%. This shows the potential of the proposed solution13372172
A framework for detecting intentions of criminal acts in social media : a case study on twitter
No full textCriminals use online social networks for various activities by including communication, planning, and execution of criminal acts. They often employ ciphered posts using slang expressions, which are restricted to specific groups. Although literature shows advances in analysis of posts in natural language messages, such as hate discourses, threats, and more notably in the sentiment analysis; research enabling intention analysis of posts using slang expressions is still underexplored. We propose a framework and construct software prototypes for the selection of social network posts with criminal slang expressions and automatic classification of these posts according to illocutionary classes. The developed framework explores computational ontologies and machine learning (ML) techniques. Our defined Ontology of Criminal Expressions represents crime concepts in a formal and flexible model, and associates them with criminal slang expressions. This ontology is used for selecting suspicious posts and decipher them. In our solution, the criminal intention in written posts is automatically classified relying on learned models from existing posts. This work carries out a case study to evaluate the framework with 8,835,290 tweets. The obtained results show its viability by demonstrating the benefits in deciphering posts and the effectiveness of detecting user’s intention in written criminal posts based on ML11
A game theoretical semantics for a logic of formal inconsistency
No full textThis paper introduces a game theoretical semantics for a particular logic of formal inconsistency called mbC28593695
Parametric study of tubular KK multiplanar steel connections
No full textThis paper presents a parametric study of symmetrically loaded multiplanar KK connections in circular hollow steel sections. The connections were designed with gaps between the diagonal braces. Analyses were performed using the commercial finite element program Ansys. A total of 54 KK connections and their corresponding uniplanar K connections were analyzed and compared in terms of the connection resistance. A new objective criterion to assess the two failure modes most often occurring in KK connections is proposed. Failure mode 1 is observed when two neighboring diagonal braces loaded in the same sense act as one brace penetrating the chord together. In failure mode 2, excessive deformation is observed in the chord region between two neighboring braces, folding the chord wall. However, in some cases, the failure mode is not easily identified, or both failure types are present The proposed criterion is based on the diametric deformation of the chord and objectively assesses the failure mode. By comparing the connection resistance of KK and K connections as determined using numerical analyses, analytical expressions to predict the connection resistance of KK connections were developed. The expressions accurately predict the connection resistance based on geometric parameters and the resistance of the corresponding uniplanar K connection114188195COORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPES01-P-11187/2007V&M do Brasil Compan
Presidential Election and FIFA World Cup
No full textOrientador: Carmen Zink BologniniTese (doutorado) - Universidade Estadual de Campinas, Instituto de Estudos da LinguagemResumo: O presente texto apresenta os resultados dos estudos de práticas educacionais com materiais didáticos multimídia que têm sido propostos recentemente para o estudo de Língua Portuguesa no Ensino Médio. Para isso, foram selecionados dois tipos de materiais. O primeiro é composto por análises de cenas de filmes desenvolvidas pelo grupo de pesquisa "Relações Institucionalmente Determinadas: História e Ideologia", coordenado pela Profa. Dra. Carmen Zink Bolognini (IEL/Unicamp). Tais análises têm sido trabalhadas anualmente, desde 2007, em oficinas com os alunos que participam do programa "Ciência & Arte nas Férias", desenvolvido anualmente pela Pró-Reitoria de Pesquisa da Unicamp. Dessa prática, analisamos as avaliações dos alunos sobre a oficina apresentadas à coordenação do programa. O segundo conjunto de atividades foi desenvolvido pelo Projeto Conexão Linguagem, integrante do Projeto Condigitais (MEC/MCT/FNDE/UNICAMP), que produziu material multimídia para o ensino de Língua Portuguesa (entre outras disciplinas) no Ensino Médio. Os conteúdos produzidos são compostos por vídeos, programas de rádio, atividades de aprofundamento e jogos digitais que estão disponíveis no site do Ministério da Educação. O material Conexão Linguagem foi trabalhado em aulas com 30 alunos do Ensino Médio de escolas estaduais de Campinas reunidos em um projeto realizado na Unicamp. A análise das atividades foi feita a partir de respostas dos alunos às atividades que compõem o material, pelas suas avaliações das práticas educacionais e pelos registros da professora em diário de campo. Todas as análises foram feitas com base nos fundamentos teóricos da Análise de Discurso de perspectiva materialista. Elas indicam que os materiais trabalhados instauram outras práticas educacionais, diferentes daquelas desenvolvidas com materiais que circulam em meios impressos, promovendo o deslocamento das posições-sujeito professor e aluno. Esse deslocamento promove e é promovido pela possibilidade de acesso a textos e ambientes diferentes daqueles que se apresentam impressos, agregando o envolvimento dos alunos nas atividades e a ampliação das possibilidades das práticas educacionaiSAbstract: The aim of this work is to present the results of studies about educational practices with multimedia teaching materials that have been proposed recently for the study of Portuguese language in high school. For this purpose, we selected two different materials: analyzes of movie scenes developed by the research group coordinated by Prof. Dr. Carmen Zink Bolognini (IEL/Unicamp); and activities of the Project Condigitais (MEC/MCT/FNDE/UNICAMP), which produced multimedia materials for the teaching of Portuguese language (among other academic disciplines) in high school. All analyzes were made based on Discourse Analysis materialist perspective. They indicate that the multimedia materials developed other educational practices, different from those in print media, promoting displacement of teacher and student positions. It promotes and is promoted by the possibility of access to different texts and environments, adding the involvement of students in activities and expanding the possibilities of educational practicesDoutoradoLíngua MaternaDoutora em Lingüística Aplicad
A hybrid machine learning framework to predict mortality in paralytic ileus patients using electronic health records (EHRs)
No full textParalytic ileus (PI) is the pseudo-obstruction of the intestine secondary to intestinal muscle paralysis. Causes of PI include electrolyte imbalances, gastroenteritis (inflammation or infection of the stomach or intestines), overuse of medications, abdominal surgery, etc. Predicting mortality in PI patients hospitalized to ICU is crucial for assessing the severity of illness and adjudicating the value of treatment strategy and resource planning. We have developed a Statistically Robust Machine Learning based Mortality Prediction framework namely SRML-MortalityPredictor that could potentially help intensivists, surgeons, and other medical professionals to carefully plan treatment strategies for critically ill PI patients. We used MIMIC III v1.4, a publicly available ICU database to extract patients data (with age > 18 years old) admitted to the ICU with paralytic ileus (PI) as their primary illness. At phase 1, the SRML-MortalityPredictor framework uses univariate statistical analysis to filter out those risk factors which are not associated with the label of the data. Subsequently, it uses the risk survival statistical methods such as cox-regression and Kaplan–Meier survival analyses. The cox-regression analysis provides the hazard ratio about the potential PI risk factors that later used in conjunction with the Kaplan–Meier analysis to generate a rank order list (highest to lowest risk factors). At phase 2, we used several machine learning classification approaches such as linear discriminant analysis (LDA), Gaussian naive bayes (GNB), decision tree (DT) model, k-nearest neighbor (KNN), and support vector machine (SVM) to find the one with highest predictive power using the rank order features extracted at phase 1. We have evaluated the SRML-MortalityPredictor framework and recorded the accuracy, sensitivity, specificity, receiver operating characteristic (ROC) curves, and area under the curve (AUC) scores for each model. The SRML-MortalityPredictor framework with support vector machine (using RBF kernel) showed better performance and yielded an accuracy score: 81.30% and AUC score: 81.38% while predicting mortality in PI patients. We demonstrated a feasible framework for the mortality risk prediction in PI patients admitted to the ICU. The proposed framework could potentially be helpful for intensivists in clinical decision making. Further research is necessary to incorporate more risk factors associated with PI patients to ensure the adaptability of SRML-MortalityPredictor at the bedsid