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Martins R.C.,University of Brasilia | Filgueiras T.S.,Institute Botanica | Graciano-Ribeiro D.,University Federal Of Goiasgo | Somavilla N.S.,University Federal Of Juiz Of Foramg

A new species of Allagoptera from the Cerrado of central Brazil is described. The new species is distinguished by its solitary habit, open crown, and very long inflorescence rachis conspicuously curved at maturity. The new species, A. robusta, is compared morphologically and anatomically with A. campestris and A. leucocalyx. © 2015 Magnolia Press. Source

Tanure C.B.G.S.,University of Brasilia | Santos J.S.,University Federal Of Goiasgo | Oliveira E.M.,University of Brasilia | Laboissiere M.,State University of Goias | And 4 more authors.
Revista Brasileira de Ciencia Avicola

The aim of this study was to evaluate the effect of digestible threonine supplementation in the starter diet on the performance, intestinal parameters, and nutrient metabolism of broilers derived from breeders of different ages. In total, 480 one-day-old Cobb chicks, derived from 38-or 49-week-oldbreeders, were housed in experimental battery cages until 21 days of age and fed four different threonine levels (800, 900, 1,000, or 1,100 mg/kg) in the starter feed. A completely randomized experimental design in a 2x4 factorial arrangement (breeder age x threonine levels) was applied, totaling eight treatments with five replicates of 12 birds each. Broilers from older breeders fed 800 mg digestible threonine/kg of diet presented higher weight gain, with a positive linear effect. There was also an interaction between breeder age and threonine levels for the weight gain of 21-d-old broilers supplemented at maximum level of 1,003 mg Thr/kg diet during the starter phase. There was no effect of breeder age or threonine levels on nutrient metabolism during the period of 17-21 days. There was no influence of breeder age or threonine levels in the starter diet on intestinal morphometric measurements, absorption area, or percentage of goblet cells. © 2015, Fundacao APINCO de Ciencia e Tecnologia Avicolas. All rights reserved. Source

Diniz-Filho J.A.F.,University Federal Of Goiasgo | Bino L.M.,University Federal Of Goiasgo | Sakamoto M.,University of Reading | Brusatte S.L.,University of Edinburgh
Revista Brasileira de Paleontologia

Phylogenetic Eigenvector Regression (PVR) is a flexible comparative method that allows testing several hypotheses on phylogenetic signal and correlated evolution among traits. Selected phylogenetic eigenvectors extracted from a phylogenetic distance matrix among taxa allow representing their phylogenetic relatedness in a raw-data form (i.e. instead of a distance matrix) and can then be used as explanatory variables in statistical models aiming to estimate phylogenetic signal or phylogenetically corrected correlations. Because of the growing use of PVR by paleobiologists in recent times, here the main theoretical/statistical basis of the method and the developments made in the 15 years after its original proposition are reviewed, highlighting further potential applications in paleobiology. For the first time, a multivariate extension of the phylogenetic signal-representation curve for estimating phylogenetic signal is presented. Another innovation is to show how PVR can be used to assess morphological disparity in a phylogenetic context. A dataset of cranial morphology and function of 35 theropod dinosaur genera is used to illustrate the applications of PVR and how it can be used to answer four questions: (i) what are the phylogenetic patterns in theropod skull shape? (ii) is possible to tease apart the evolutionary models underlying variation in traits? (iii) how are evolutionary history, function, and diet related to variation in theropod skulls? (iv) what are the evolutionary components of morphological disparity in theropod skulls? Answering these questions provide a roadmap for using PVR to address a range of issues relevant to contemporary paleobiology research programs. © 2014 by the Sociedade Brasileira de Paleontologia. Source

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