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Rio De Janeiro, Brazil

Santos-Goncalves A.P.,Federal University of Vicosa | Filgueiras T.S.,IBGE Inc | Clark L.G.,Iowa State University
Systematic Botany | Year: 2011

Atractantha shepherdiana , a new species of woody bamboo from Brazil, is here described and illustrated, and an identification key based on vegetative characters for all the species of the genus is provided. In its vegetative state, the new species resembles Atractantha amazonica by having culms with a small central lumen. The new species differs from A. amazonica mainly because of the occurrence of tomentose-velvety ochre trichomes on the upper and lower portions of young intrnodes, pseudopetiolate blades of the culm leaves that are initially erect and later reflexed, and by the girdle with hirtellous-hispid dark-brown trichomes. © Copyright 2011 by the American Society of Plant Taxonomists. Source

An alphabetical list of all the validly published names of Brazilian taxa of Bauhinia L. s.str. (= Bauhinia subg. Bauhinia) including those first published in Pauletia Cav. is presented with details of all types including 30 new typifications. All names are assigned to their accepted taxa following the classification for Leguminosae tribe Cercideae published by Lewis & Forest in 2005. Source

Braz M.H.L.B.,University of Lisbon | Siqueira S.W.M.,State University of Rio de Janeiro | Rodrigues D.D.S.E.S.,IBGE Inc | Melo R.N.,Pontifical Catholic University of Rio de Janeiro
Computers in Human Behavior | Year: 2011

The development of instructional content using Information Technologies is an expensive, time-consuming and complex process that requires new methodologies. It was in this context that the concept of Learning Objects (LOs) was proposed in order to promote reuse. However, this goal is not yet fully attained and new contributions to increase reuse are still welcome. Besides, if content is conveyed in LOs that are easier to reuse, they must be combined and sequenced in order to build more elaborated and complex content. This paper presents a strategy to deal with these problems based on the definition of small LOs here called Component Objects (COs). These COs are structured and combined according to a conceptual metamodel, which is the basis for the definition of conceptual schemas representing the existing material, including not only content but also practice. This strategy for searching, extracting, and sequencing COs, supports a teacher to better control the implementation of complex content, reducing errors in the authoring process. This approach includes a specification language and an algorithm for semi-automatic sequencing learning content and practice. Finally, a case study that shows the proposed approach and some results of using the algorithm are presented. © 2010 Elsevier Ltd. All rights reserved. Source

One of the main purposes of epidemiological studies is to estimate causal effects. Causal inference should be addressed by observational and experimental studies. A strong constraint for the interpretation of observational studies is the possible presence of unobserved confounders (hidden biases). An approach for assessing the possible effects of unobserved confounders may be drawn up through the use of a sensitivity analysis that determines how strong the effects of an unmeasured confounder should be to explain an apparent association, and which should be the characteristics of this confounder to exhibit such an effect. The purpose of this paper is to review and integrate two independent sensitivity analysis methods. The two methods are presented to assess the impact of an unmeasured confounder variable: one developed by Greenland under an epidemiological perspective, and the other developed from a statistical standpoint by Rosenbaum. By combining (or merging) epidemiological and statistical issues, this integration became a more complete and direct sensitivity analysis, encouraging its required diffusion and additional applications. As observational studies are more subject to biases and confounding than experimental settings, the consideration of epidemiological and statistical aspects in sensitivity analysis strengthens the causal inference. Source

Viana P.L.,Federal University of Minas Gerais | Filgueiras T.S.,IBGE Inc | Paiva E.A.S.,Federal University of Minas Gerais
Brittonia | Year: 2011

Recent bamboo collections from Brazil, and the study of specimens from several Brazilian herbaria revealed that the species described as Eremocaulon setosum, subtribe Guaduineae, in fact fits within the Arthrostylidiinae genus Aulonemia, based on floral and anatomical characters. Several characters found in this species, such as paniculate determinate synflorescences, solitary spikelets, an abaxial marginal green stripe on the foliage leaf blades, absence of stomata on the entire adaxial side of the leaf blade, and intercostal fibers in the mesophyll are typical features of the subtribe Arthrostylidiinae. The new combination Aulonemia setosa is here proposed, an epitype is designated, and a broader distributional range of this species is documented. © 2010 The New York Botanical Garden. Source

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