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Search Results: 1 - 10 of 410558 matches for " Rodrigo M. Feitosa "
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The Ant Genus Sphinctomyrmex Mayr (Hymenoptera, Formicidae, Cerapachyinae) in the Neotropical Region, with the Description of Two New Species
Rodrigo M. Feitosa,Carlos Roberto F. Brand o,Fernando Fernández,Jacques C. H. Delabie
Psyche , 2012, DOI: 10.1155/2012/342623
Abstract: The ant genus Sphinctomyrmex has been represented in the Neotropical Region until now by a single species, S. stali, known only from sparse localities in southeastern Brazil. Two new neotropical species are herein described, S. marcoyi sp. n. and S. schoerederi sp. n. from workers collected in the Brazilian Amazon and Atlantic Forest, respectively. New records for Sphinctomyrmex stali are presented, and the species is redescribed together with discussions on its high morphological variation and the identity of its type specimen. A key for the neotropical Sphinctomyrmex workers, images of all species presently known, and a distribution map are supplied.
Cerrado ground-dwelling ants (Hymenoptera: Formicidae) as indicators of edge effects
Brand?o, Carlos Roberto F.;Silva, Rogério R.;Feitosa, Rodrigo M.;
Zoologia (Curitiba) , 2011, DOI: 10.1590/S1984-46702011000300012
Abstract: large-scale agricultural production in brazil preferentially occupies plateaus reclaimed from areas originally covered by cerrado (savanna). depending on the region, a percentage of the pristine vegetation coverage must be preserved by law, resulting in the creation of fragmented legal cerrado reserves. the geometry of these relatively small legal reserves creates new habitat edges and ecotones, whose effects on the invertebrate fauna are poorly understood. this study aimed to assess the effects of abrupt edges resulting from soy production on ground-dwelling ant assemblages in the brazilian cerrado. the study sites are located within the amazon region, in the state of maranh?o, northern brazil, but were covered by cerrado on a relatively low plateau, irregularly inter-spaced with gallery forests along streams. we compared species richness and species composition of ground-dwelling ants along eight transects set 0, 50, 100, 150, 200, and 250 m into the sensu stricto cerrado and 50 and 100 m into the soy field. the collecting periods covered the wet and dry seasons. effects on ant species richness were non-significant, although composition of the assemblages was significantly affected by edge effects, which were, in part, found to be species specific. we hypothesize that edge effects are probably greater than estimated because of the shape and complexity of reserves. consideration of edge effects in the cerrado biome should enable the design of appropriate reserve sizes and shapes to meet conservation goals.
Cyatta abscondita: Taxonomy, Evolution, and Natural History of a New Fungus-Farming Ant Genus from Brazil
Jeffrey Sosa-Calvo, Ted R. Schultz, Carlos R. F. Brand?o, Christiana Klingenberg, Rodrigo M. Feitosa, Christian Rabeling, Maurício Bacci, Cauê T. Lopes, Heraldo L. Vasconcelos
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0080498
Abstract: Cyatta abscondita, a new genus and species of fungus-farming ant from Brazil, is described based on morphological study of more than 20 workers, two dealate gynes, one male, and two larvae. Ecological field data are summarized, including natural history, nest architecture, and foraging behavior. Phylogenetic analyses of DNA sequence data from four nuclear genes indicate that Cyatta abscondita is the distant sister taxon of the genus Kalathomyrmex, and that together they comprise the sister group of the remaining neoattine ants, an informal clade that includes the conspicuous and well-known leaf-cutter ants. Morphologically, Cyatta abscondita shares very few obvious character states with Kalathomyrmex. It does, however, possess a number of striking morphological features unique within the fungus-farming tribe Attini. It also shares morphological character states with taxa that span the ancestral node of the Attini. The morphology, behavior, and other biological characters of Cyatta abscondita are potentially informative about plesiomorphic character states within the fungus-farming ants and about the early evolution of ant agriculture.
Gas exchange in massai grass under five nitrogen fertilization levels during establishment and regrowth
Lopes, Marcos Neves;Lacerda, Claudivan Feitosa de;Candido, Magno José Duarte;Pompeu, Roberto Cláudio Fernandes Franco;Silva, Rodrigo Gregório da;Lopes, José Wellington Batista;Fernandes, Francisco Ronaldo Belém;Bezerra, Francisco Marcus Lima;
Revista Brasileira de Zootecnia , 2011, DOI: 10.1590/S1516-35982011000900004
Abstract: the objective of this study was to evaluate gas exchange in the massai grass during establishment and regrowth cycles in a greenhouse, using five nitrogen (n) fertilization levels. a completely randomized split-plot design of five nitrogen levels (0; 150; 300; 450 and 600 mg n?dm-3 of soil) was employed with the n levels as plots, and the cycles (establishment, regrowth 1 and 2) as subplots, evaluated with five replicates. we evaluated leaf transpiration (e), leaf temperature (tfol), leaf photosynthesis rate (a), leaf carbon dioxide concentration (ci), stomatal conductance (gs), photosynthesis/transpiration ratio (a/e), photosynthesis/conductance ratio (a/gs), chlorophyll relative index (cri), and nitrogen sufficiency index (nsi). growth cycles influenced all physiological characteristics, except for nsi. n fertilization levels affected tfol, a, cri and nsi variables, whereas for gs, e, ci, a/e and a/gs it did not occur. a increased from 6.38 to 10.33 μmol?m-2.s-1, at levels 0 and 600 mg n?dm-3 of soil, respectively. gas exchange in the massai grass was favored by nitrogen fertilization, since the cycles amended these characteristics of the grass.
A model for intra-familial distribution of an infectious disease (Chagas' disease)
Feitosa, M. F.;Krieger, H.;
Memórias do Instituto Oswaldo Cruz , 1993, DOI: 10.1590/S0074-02761993000200009
Abstract: a probabilistic model for intra-familial distribution of infectous disease is proposed and applied to the prevalence of positive serology for trypanosoma cruzi infection in northeastern brazilian sample. this double with one tail excess model fits satisfactorily to the data and its interpretation says that around 51% of these 982 families are free of infection risk; among those that are at risk, 3% have a high risk (0.66), probably due to high domestic infestation of the vector bug; while 97% show a small risk (0.11), probably due to accidental, non-domestic transmission.
An appraisal of the epidemiology of Trypanosoma cruzi serology in Brazil
Feitosa, M. F.;Krieger, H.;
Memórias do Instituto Oswaldo Cruz , 1991, DOI: 10.1590/S0074-02761991000200004
Abstract: a large bibliographic survey provided data on trypanosoma cruzi serology covering the period l948-l984. epidemiological-demographic methods provided an estimate of 11% for the prevalenceof positive serology in brazil, by 1984. significant temporal trends were observed for most of the brazilian geographical regions as well as for brazil, as a whole. the parabolic curve that fit best for the entire country, indicates that by 1991, the incidence of new positive serology would be close to zero. this conclusion needs further fine-adjustment, since the forecast point is somewhat distant from the measured period.
Uma leitura intertextual da poesia de Alberto Caeiro à luz da sabedoria zen-budista
Márcia Munir Miguel Feitosa
Caligrama : Revista de Estudos Romanicos , 1998,
Abstract: Resumo: Análise da poesia de Alberto Caeiro, heter nimo de Fernando Pessoa, à luz da filosofia zen-budista, tanto no que concerne ao culto da natureza, como no que diz respeito à quest o do eu, inerente ao poeta português e à filosofia Zen. O estudo ainda inclui o levantamento das possíveis afinidades formais e estilísticas entre a poesia japonesa, representada pelos hai-kais, e a poesia sensacionalista de Caeiro. Palavras-chave: Literatura portuguesa; Fernando Pessoa; Alberto Caeiro; filosofia; Zen-budismo; literatura japonesa. Resumen: Análisis de la poesia de Alberto Caeiro, heterónimo de Fernando Pessoa a la luz de la filosofía zen-budista, tanto que concierne al culto de la naturaleza, como que dice respecto a la cuestión del yo, inherente al poeta portugués y a la filosofía zen. El estúdio aún incluye las posibles afinidades formales y estilísticas entre la poesia japonesa, representada por los hai-kais, y la poesia sensacionista de Caeiro. Palabras-clave: Literatura portuguesa; Fernando Pessoa; Alberto Caeiro; filosofía; Budismo Zen; literatura japonesa.Keywords: Portuguese literature; Fernando Pessoa; Alberto Caeiro; Philosophy; Zen buddhism; japanese literature.
The leaf litter ant fauna of an Atlantic Forest area in the Cantareira State Park – S o Paulo, Brazil
Rodrigo dos Santos Machado Feitosa,Andre Soliva Ribeiro
Biotemas , 2005,
Abstract: The present work surveys the leaf litter ant fauna of an Atlantic Forest area in Cantareira State Park – SP, Brazil as a complement to the project “Richness and diversity of Hymenoptera and Isoptera along a latitudinal gradient in the Atlantic Forest – the eastern Brazilian rain forest” that forms part of the BIOTA-FAPESP program. The general protocol of the project was to collect 50 leaf litter samples of 1 m2 which were then sifted and submitted to Winkler extractors for 48 hours. Sixty-two species of 25 genera in eight ant subfamilies were collected. Myrmicinae was the richest with 39 species, followed by Ponerinae (14), Ectatomminae, Heteroponerinae and Formicinae (two species each), Amblyoponinae, Proceratiinae and Dolichoderinae (one species each). The richest genera were Solenopsis and Hypoponera (12 morph-species each), and Pheidole (eight). Richness estimators indicated that the total number of species in the area should be between 68 and 85, in a confidence interval of 95%. In comparison, other locations of the evergreen Atlantic Forest have shown a significantly higher richness. Our hypothesis is that the proximity of regions of great urban concentration, allied to the factors that act on a local scale, modifies the structure of the local community of leaf litter ants.
Surgical revascularization of posterior coronary arteries without cardiopulomonary bypass
Lobo Filho, J. Glauco;Albuquerque, Jo?o Marcelo A. C. de;Gomes, Carlos Bellini G.;Siqueira, Rafael P. de;Landim, Rodrigo M.;Oliveira, Ricardo R. M. de;Oliveira, Francisco M. de;Ciarline, Ciro;Feitosa, J. Acácio;Leit?o, Maria Claudia;Pinheiro, Francisca Elita B.;Fa?anha, Erirtonio;Paes Jr, J. Nogueira;
Arquivos Brasileiros de Cardiologia , 1999, DOI: 10.1590/S0066-782X1999000500006
Abstract: objective: to assess the results observed during the early postoperative period in patients who had the posterior coronary arteries revascularized without cardiopulmonary bypass (cpb), in regard to the following parameters: age, sex,bypass grafts types, morbidity and mortality. methods: from january 1995 to june 1998, 673 patients underwent myocardial revascularization (mr). of this total, 607 (90.20%) mr procedures were performed without cpb. the posterior coronary arteries (pca) were revascularized in 298 (44.27%) patients, 280 (93.95%) without cpb. the age of the patients ranged from 37 to 88 years (mean, 61 years). the male gender predominated, with 198 men (70.7%). the revascularization of the posterior coronary arteries had the following distribution: diagonalis artery (31 patients, 10%); marginal branches of the circumflex artery (243 patients, 78.7%); posterior ventricular artery (4 patients, 1.3%); and posterior descending artery (31 patients, 10%). results: procedure-related complications without death occurred in 7 cases, giving a morbidity of 2.5%. there were 11 deaths in the early postoperative period (mortality of 3.9%). conclusion: similarly to the anterior coronary arteries, the posterior coronary arteries may benefit from myocardial revascularization without cpb.
How informative are interest rate survey-based forecasts?
Feitosa, Mateus A;Tabak, Benjamin M;
BAR. Brazilian Administration Review , 2008, DOI: 10.1590/S1807-76922008000400005
Abstract: this paper studies the information content of survey-based predictions for the brazilian short-term interest rate. we perform vector autoregression analysis to test for the dynamic relationship between market expectations of interest rates and spot interest rates, and a single regression forecasting approach. empirical results suggest that surveys may be useful in assessing market expectations (contain relevant information) and in building central bank credibility. within an inflation targeting framework they are crucial in order to receive timely feedback on market sentiment regarding the conduct of monetary policy.
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