8,248 research outputs found
Occurrence of Gastroliths in _Baurusuchus_ (Baurusuchidae, Mesoeucrocodylia) from Adamantina Formation, Bauru Basin
The fossil record of Baurusuchidae Mesoeucrocodylia in the General Salgado county and its surroundings is one of the best regarding preservation, completeness and articulation of skull and skeleton remains, including specimens that shown even the most delicate bone structures and cartilaginous tissues. 

One of them, UFRJ DG 288-R, has preserved its skull and about 80% of its skeleton. During the removal of the rock matrix, on what should be the specimen’s abdominal region, together with fragments of gastralia were observed some small well-polished weathered angulous to subrounded clasts, presumed to be gastroliths. 

These xenoliths occur in a restrict cluster, where at least four peeble-sized stones are visible in the surface of the specimen. The texture and fabrics of these rock fragments differs from the surrounding matrix, presenting darker purplish tones. In thin section, one of the fragments revealed isotropic texture, with opaque minerals in abundance, of euhedric to subhedric habits. The mineralogical composition presents mainly clay minerals as weathering products; biotite and chlorite are common, being the last the result of hidratation of the first. Although highly altered, the low quartz content, small-sized and well-formed crystals suggests maphic composition in volcanic context, possibly representing a basalt fragment. 

In extant Crocodyliformes, the occurrence of gastroliths is commonly associated with food processing in the stomach, diving ballast, hunger stress and/or supplementary mineral ingestion. 

As baurusuchids are characterized as medium to large size fully terrestrial predator/scavengers, based on skeletal data, the ballast function of gasthroliths is excluded in this case. As mentioned above, extant crocodyliforms such as _Caiman_ and _Crocodylus_ ingest stones when under stressful conditions of lack of food, water or when in high population density. Osteoderms are one of the primary sources for calcium and a reservoir for the homeostasis. The hunger stress can be observed in the osteoderms histological cuts as an abnormal concentration of osteoclasts at its inner region overwhelming the presence of osteoblasts and consuming the osteocytes. The preservation of osteoderms associated with gasthroliths may reveal if the stone ingestion in baurusuchids is a normal or driven by hunger behavior. 

The paleoenvironmental conditions dominating the Adamantina Formation during the Late Cretaceous are considered mainly arid, marked with strong seasonality, alternating long droughts and short rainy periods, associated with flashflood events. The stressful condition created during the dry season would cause famine and mass mortality, thus forcing animals to endure or escape. The baurusuchids underwent the dry seasons through behavorial responses of self burial and probably stone ingestion, although natural bahavior cannot be eliminated as a cause. 

Financial support provided by Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq, grant no 305780/2006–9), Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) and Instituto Virtual de Paleontologia/ Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (IVP/FAPERJ, grant no E–26/152.541/2006).

Digital electric field induced switching of plasmonic nanorods using an electro-optic fluid fiber
We demonstrate the digital electric field induced switching of plasmonic
nanorods between 1 and 0 orthogonal aligned states using an electro-optic fluid
fiber component. We show by digitally switching the nanorods, that thermal
rotational diffusion of the nanorods can be circumvented, demonstrating an
approach to achieve submicrosecond switching times. We also show, from an
initial unaligned state, that the nanorods can be aligned into the applied
electric field direction in 110 nanoseconds. The high-speed digital switching
of plasmonic nanorods integrated into an all-fiber optical component may
provide novel opportunities for remote sensing and signaling applications
Indicadores de consumo aparente de bens industriais: Metodologia e resultados
The aim of this paper is to describe in details the methodology used to construct the apparent consumption indicators of industrial goods in the Brazilian economy - defined as domestic production plus imports minus exports - and report the results. This indicator is important in view of the difficulties to obtain timely measures for industrial goods demand, whereas supply data are comprehensive and diversified. Departing from the principle of supply and demand equilibrium, the apparent consumption is a good proxy to demand behavior. The indices shown in this text are calculated in a monthtly basis since january, 1998, for different aggregated levels of industrial goods: general industry, manufacturing industry, capital goods industry, intermediate goods industry, consumer good industry (durables, semidurables and non-durables) and 22 different sectors of activity, as defined in the National Classification of Economic Activities (CNAE) of the Brazilian Institute of Geography and Statistics (IBGE). This paper also shows the method to obtain a monthly indicator for the gross fixed capital formation of the Brazilian economy, that is based on the apparent consumption of capital goods and that aims to replicate the methodology used by IBGE to obtain the measure of the gross fixed capital formation in the System of National Accounts
Systematic revision and phylogeny of the South American sun-spider genus Gaucha Mello-Leitão (Solifugae: Mummuciidae), with description of four new species and two new generic synonymies
The South American sun-spider genus Gaucha Mello-Leitão, 1924 is herein studied from a combined approach of cladistics and traditional taxonomy. This is the first cladistic analysis for a group of mummuciid solifuges, and it is pioneer in integrating traditional morphological characters with landmark data for inferring the phylogeny of any group of Solifugae. As a result, Gaucha is redefined and its monophyly demonstrated. Gaucha fasciata Mello-Leitão, 1924, type species of this formerly monotypic genus, is redescribed based on specimens from the type locality, in Rio Grande do Sul, Brazil. Three new species are described from Brazil: Gaucha avexada sp.nov. from Bahia and Tocantins, Gaucha curupi sp.nov. from Rio Grande do Sul, and Gaucha eremolembra sp.nov. from Minas Gerais. A fourth new species, Gaucha casuhati sp.nov., is described from Buenos Aires province, Argentina. In addition, Metacleobis Roewer, 1934 and Gauchella Mello-Leitão, 1937 are synonymized with Gaucha, following the examination of the type specimens and based upon evidence from the cladistic analysis. Gaucha fulvipes (Roewer, 1934) comb.nov., from Mato Grosso (Brazil), is therefore proposed, whereas Gaucha stoeckeli Roewer, 1934 comb.rest., from Luribay (Bolivia), is restored into its original name combination. Gaucha ibirapemussu (Carvalho et al., 2010) comb.nov. and Gaucha mauryi (Rocha, 2001) comb.nov., from the Brazilian states of Piauí and Bahia, are also transferred, from Mummucia Simon, 1879. Gaucha is here defined, among other characters, by the large size of the cheliceral movable finger MP tooth as compared to MM tooth, and by the presence of a pronounced gnathal edge carina on the movable finger mucron of males. Two species groups are herein defined within the genus: the fasciata group, for G. casuhati sp.nov., G. curupi sp.nov., G. fasciata, G. fulvipes comb. nov. and G. stoeckeli comb.rest., and the ibirapemussu group, for G. avexada sp.nov., G. eremolembra sp.nov., G. ibirapemussu comb. nov. and G. mauryi comb.nov. A key to the identification of Gaucha species is included. Fil: Botero Trujillo, Ricardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Ott, Ricardo. Fundacao Zoobotanica Do Rio Grande Do Sul; BrasilFil: Carvalho, Leonardo S.. Universidade Federal Do Piauí; Brasil. Universidade Federal de Minas Gerais; Brasi
Water requirement and yield of fig trees under different drip irrigation management.
This work aimed to study the effect of drip irrigation management on growth and yield of the 'Roxo de Valinhos' fig tree (Ficus carica L.), at three years old, and to determine crop coefficients (Kc) and its water requirement (ETc) under Baixada Fluminense climate and soil conditions, state of Rio de Janeiro, Brazil. The study was carried out in the experimental area of SIPA (Sistema Integrado de Produção Agroecológica) in Seropédica, Rio de Janeiro State, from July 2011 to May 2012. The experimental area was divided in two blocks, named B1 (sandy clay loam texture) and B2 (loamy sand texture). In each block, irrigation frequencies (IF) of two (T1) and four days (T2) were evaluated, as well as the irrigation absence (T3). Irrigation management and water consumption determination were performed through the soil water balance, using the TDR technique. Plant growth was not affected by IF, differing only in the number of produced internodes. For both soil textures, the mean Kc was 0.60, with a significant difference (p<0.05) only for IF. The estimated mean yield showed no significant differences between both textural classes, ranging from 6,612 kg ha-1 (T3) to 8,554 kg ha-1 (T1). This study indicates the importance of irrigation frequency in the irrigation management of fig trees cultivated in soils with different physical characteristics
Coronaviruses Detected in Brazilian Wild Birds Reveal Close Evolutionary Relationships with Beta- and Deltacoronaviruses Isolated From Mammals
This study showed that the most of the coronaviruses (CoVs) detected in Brazilian wild birds clustered with the mouse hepatitis virus A59 strain, belonging to the BetaCoV group. Furthermore, CoV detected in two different bird species, Amazona vinacea and Brotogeris tirica, clustered with a CoV isolated from Sparrow (SpaCoV HKU17) belonging to a monophyletic group related with the CoVs isolated from swines (PorCoV HKU15), both belonging to the DeltaCoV genus, previously unreported in South America. Considering the risk of inter-species host switching and further adaptation to new hosts, detection in bird species of CoVs closely related to mammal CoVs should warn for the potential emergence of new threatening viruses.Fundação de Amparo à Pesquisa do Estado de São Paulo (Grants 2013/03922-6 and 2011/50919-5
Cell-Envelope Remodeling as a Determinant of Phenotypic Antibacterial Tolerance in Mycobacterium tuberculosis
[Image: see text] The mechanisms that lead to phenotypic antibacterial tolerance in bacteria remain poorly understood. We investigate whether changes in NaCl concentration toward physiologically higher values affect antibacterial efficacy against Mycobacterium tuberculosis (Mtb), the causal agent of human tuberculosis. Indeed, multiclass phenotypic antibacterial tolerance is observed during Mtb growth in physiologic saline. This includes changes in sensitivity to ethionamide, ethambutol, d-cycloserine, several aminoglycosides, and quinolones. By employing organism-wide metabolomic and lipidomic approaches combined with phenotypic tests, we identified a time-dependent biphasic adaptive response after exposure of Mtb to physiological levels of NaCl. A first rapid, extensive, and reversible phase was associated with changes in core and amino acid metabolism. In a second phase, Mtb responded with a substantial remodelling of plasma membrane and outer lipid membrane composition. We demonstrate that phenotypic tolerance at physiological concentrations of NaCl is the result of changes in plasma and outer membrane lipid remodeling and not changes in core metabolism. Altogether, these results indicate that physiologic saline-induced antibacterial tolerance is kinetically coupled to cell envelope changes and demonstrate that metabolic changes and growth arrest are not the cause of phenotypic tolerance observed in Mtb exposed to physiologic concentrations of NaCl. Importantly, this work uncovers a role for bacterial cell envelope remodeling in antibacterial tolerance, alongside well-documented allterations in respiration, metabolism, and growth rate
Erythropoietin reduces the expression of myostatin in mdx dystrophic mice
Erythropoietin (EPO) has been well characterized as a renal glycoprotein hormone regulating red blood cell production by inhibiting apoptosis of erythrocyte progenitors in hematopoietic tissues. EPO exerts regulatory effects in cardiac and skeletal muscles. Duchenne muscular dystrophy is a lethal degenerative disorder of skeletal and cardiac muscle. in this study, we tested the possible therapeutic beneficial effect of recombinant EPO (rhEPO) in dystrophic muscles in mdx mice. Total strength was measured using a force transducer coupled to a computer. Gene expression for myostatin, transforming growth factor-beta 1 (TGF-beta 1), and tumor necrosis factor-alpha (TNF-alpha) was determined by quantitative real time polymerase chain reaction. Myostatin expression was significantly decreased in quadriceps from mdx mice treated with rhEPO (rhEPO = 0.60 +/- 0.11, control= 1.07 +/- 0.11). On the other hand, rhEPO had no significant effect on the expression of TGF-beta 1 (rhEPO = 0.95 +/- 0.14, control= 1.05 +/- 0.16) and TNF-alpha (rhEPO = 0.73 +/- 0.20, control= 1.01 +/- 0.09). These results may help to clarify some of the direct actions of EPO on skeletal muscle.Fac Med ABC, BR-09060650 Santo Andre, SP, BrazilUniv São Paulo, Inst Ciencias Biomed, BR-05508 São Paulo, BrazilUniversidade Federal de São Paulo, Inst Ciencias Quim Ambientais & Farmaceut, Diadema, SP, BrazilUniversidade Federal de São Paulo, Inst Ciencias Quim Ambientais & Farmaceut, Diadema, SP, BrazilWeb of Scienc
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