994 resultados para A. cf. cretaceous


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O objetivo do trabalho foi avaliar a eficácia de sementes de abóbora e mamão desidratadas e moídas, no controle de helmintos parasitos de Astyanax cf. zonatus. Sessenta peixes foram distribuídos em doze recipientes, um peixe/litro. O experimento constituiu de quatro tratamentos e três repetições: TJ = peixes deixados em jejum; TRC = peixes alimentados com r§Ã£o comercial; TSA = peixes alimentados ad libitum com abóbora, e TSM = peixes alimentados ad libitum com mamão. Após sete dias de aliment§Ã£o, todos os peixes foram pesados, e o sangue foi retirado para extensão sanguínea. A eficácia foi determinada, verificando a presença de parasitos nas brânquias, no estômago e no intestino. Os peixes do TJ e TSM apresentaram perda de peso (39% e 25%, respectivamente). O TSA apresentou melhor eficácia no controle de nematóides do intestino e do estômago (95,26% e 92,48%). No controle de monogenéticos TSM promoveu 72% de eficácia. Na hematologia observou-se aumento de monócitos nos peixes do TSM e os valores de eosinofilos diminuíram nos tratamentos TSA, TSM e TRC. Assim pode-se concluir que a aliment§Ã£o com abóbora pode ser utilizado como um controle alternativo eficaz de nematóides intestinais do lambari.

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Fund§Ã£o de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The Constant Flux: Constant Sedimentation (CF:CS) and Constant Rate of Supply (CRS) of unsupported/excess Pb-210 models have been applied to a Pb-210 data set providing of eighteen sediments profiles sampled at four riverine systems occurring in Brazil, South America: Corumbatai River basin (S1=Site 1, Sao Paulo State), Atibaia River basin (S2=Site 2, Sao Paulo State), Ribeirao dos Bagres basin (S3=Site 3, Sao Paulo State) and Amazon River mouth. (S4=Site 4, Amapa State). These sites were chosen for a comparative evaluation of the performance of the CF:CS and CRS models due to their pronounced differences on the geographical location, geological context, soil composition, biodiversity, climate, rainfall, and water flow regime, among other variable aspects. However, all sediments cores exhibited a common denominator consisting on a database built from the use of the same techniques for acquiring the sediments major chemical composition (SiO2, Al2O3, Na2O, K2O, CaO, MgO, Fe2O3, MnO, P2O5, TiO2 and LOI-Loss on Ignition) and unsupported/excess 210Pb activity data. In terms of sedimentation rates, the performance of the CRS model was better than that of the CF:CS model as it yielded values more compatible with those expected from field evidences. Under the chronological point of view, the CRS model always provided ages within the permitted range of the Pb-210-method in the studied sites, whereas the CF:CS model predicted some values above 150 years. The SiO2 content decreased in accordance with the LOI increase in all cores analyzed and such inverse relationship was also tracked in the SiO2-LOI curves of historical trends. The SiO2-LOI concentration fluctuations in sites S1 and S3 also coincided with some Cu and Cr inputs in the drainage systems. (C) 2014 Elsevier Ltd. All rights reserved.

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Fund§Ã£o de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The fossil genus Clypeina (Michelin, 1845) comprises some 40 species. We describe Clypeina tibanai, a new species from ? upper Albian-Cenomanian strata of the Potiguar Basin, Brazil, characterised by closely set verticils of tubular, bended laterals. It is compared with Clypeina hanabataensis Yabe & Toyama, 1949, a Late Jurassic species, and with Pseudoactinoporella fragilis (Conrad, 1970), an Early Cretaceous taxon. The new species belongs to a short list of green algae found in the young South Atlantic oceanic corridor, an assemblage defining a phycological paleobioprovince discrete from that of the Tethyan realm.

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Coorden§Ã£o de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fund§Ã£o de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Najash rionegrina Apesteguia & Zaher, 2006, a terrestrial fossil snake from the Upper Cretaceous of Argentina, represents the first known snake with a sacrum associated with robust, well-developed hind limbs. Najash rionegrina documents an important gap in the evolutionary development towards limblessness, because its phylogenetic affinities suggest that it is the sister group of all modern snakes, including the limbed Tethyan snakes Pachyrhachis, Haasiophis, and Eupodophis. The latter three limbed marine fossil snakes are shown to be more derived morphologically, because they lack a sacrum, but have articulated lymphapophyses, and their appendicular skeleton is enclosed by the rib cage, as in modern snakes.

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An anatomical description of the solenid Solen cf. exiguus DUNKER 1862, collected in the Gulf of Thailand, is provided. The anatomical features include high antero-posterior elongation; mantle lobes widely fused with each other; powerful pallial muscles; fused siphons with capacity of autotomy; wide and partially hollow foot; complete separation between gastric style sac and adjacent portion of intestine; all possible common characters of the family. Some so far exclusive attributes include short anterior pallial tentacles; pair of muscular valves at base of siphons; and arrangement of tentacles at siphonal tip. A short discussion on the taxonomy of the Solen exiguus/leanus complex is also included.

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The cranial anatomy of Dinilysia patagonica, a terrestrial snake from the Upper Cretaceous of Argentina, is redescribed and illustrated, based on high-resolution X-ray computed tomography and better preparations made on previously known specimens, including the holotype. Previously unreported characters reinforce the intriguing mosaic nature of the skull of Dinilysia, with a suite of plesiomorphic and apomorphic characters with respect to extant snakes. Newly recognized plesiomorphies are the absence of the medial vertical flange of the nasal, lateral position of the prefrontal, lizard-like contact between vomer and palatine, floor of the recessus scalae tympani formed by the basioccipital, posterolateral corners of the basisphenoid strongly ventrolaterally projected, and absence of a medial parietal pillar separating the telencephalon and mesencephalon, amongst others. We also reinterpreted the structures forming the otic region of Dinilysia, confirming the presence of a crista circumfenestralis, which represents an important derived ophidian synapomorphy. Both plesiomorphic and apomorphic traits of Dinilysia are treated in detail and illustrated accordingly. Results of a phylogenetic analysis support a basal position of Dinilysia, as the sister-taxon to all extant snakes. The fossil taxa Yurlunggur, Haasiophis, Eupodophis, Pachyrhachis, and Wonambi appear as derived snakes nested within the extant clade Alethinophidia, as stem-taxa to the crown-clade Macrostomata. The hypothesis of a sister-group relationship between Dinilysia and Najash rionegrina, as suggested by some authors, is rejected by the results of our analysis.

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The Ipanema alkaline-carbonatitic complex is part of the Meso-Cenozoic alkaline magmatism located within the southeastern part of the Brazilian Platform. Drill-core and field sampling have indicated the occurrence of glimmerites, with subordinate shonkinites (mela-syenites), clinopyroxene-bearing glimmerites, diorites and syenites. The glimmerites are cross-cut by lamprophyric dykes and calciocarbonatites. Fenitization has deeply affected the country rocks, originating dioritic and syenitic rocks. The Ipanema rocks show a distinct potassic affinity. The initial Sr-Nd- isotopic composition of the Ipanema rocks ((87)Sr/(86)Sr = 0.70661-0.70754 and (143)Nd/(144)Nd = 0.51169-0.51181) is similar to that of tholeiitic and potassium-rich-alkaline rocks of the Eastern Paraguay. Stable isotope data for the Ipanema calciocarbonatite suggest interaction with fluids at temperatures typical of hydrothermal stages, as hypothesized for other carbonatite complexes from southeastern Brazil. The chemical differences between the lamprophyre, glimmerites, carbonatites, apatitites and magnetitites, and the absence of marked REE enrichment in the evolved lithologies, all indicate that fractional crystallization and accumulus of liquidus phases in a magma reservoir, likely coupled with liquid immiscibility processes, may have played an important role in the genesis of the Ipanema rocks.

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The water vapor conductance (G(H20)) of the neosauropod eggs from the Lower Cretaceous Sanagasta nesting site in La Rioja Province, Argentina, was examined and compared with other Cretaceous Argentinean oological material. The 2900 mgH(2)O/day.Torr G(H2O) of the Sanagasta eggshells confirms an extremely moist nesting environment and supports field observations of dug-out nests in a geothermal setting. The observed thinning of the outer eggshell surface during incubation increases gas conductance and concomitantly decreases eggshell mechanical resistance during the late ontogenetic stages, thus facilitating embryonic development and hatching. The Sanagasta and Entre Rios Province faveoloolithid eggs display the highest and comparable 61120 values and share several morphological and diagenetic characters, indicating comparable nesting strategy in geothermal settings. However, the faveoloolithid Yamintie and La Pampa Province specimens cluster together with lower G(H20) values closer to the megaloolithid eggs. The Gnu) of the megaloolithid egg Megaloolithus patagonicus was reconsidered and new results are now congruent with other reported megaloolithid GH2O values. Additionally, we hypothesize that V-shaped pore canals of M. patagonicus, which upper sections reach only the top third or half eggshell thickness and, a wider section in the middle would not compromise the overall egg mechanical resistance like vertical pores connecting directly the outer to the inner eggshell surfaces. Such pore spatial arrangement and geometry would enhance, as the eggshell thins during incubation, a greater G(H2O), G(O2) and G(CO2) and facilitate embryonic development in high moisture nesting contents. Overall, data suggests that neosauropod nesting and brooding behaviors were dependent on elevated moisture nesting environments.

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A new gymnosperm taxon from the Lower Cretaceous (upper Aptian to possibly lower Albian) Crato Formation of Brazil, Duartenia araripensis gen. nov. et sp. nov. is described. The most prominent specimen, a branch with attached lateral branches of higher orders exhibits a distinct anisotomous branching pattern. The very dense wood is composed of tracheids with spaced and partly contiguous uniseriate pits and low rays with one pit per cross-field (mixed protopinaceous type). When foliage is not abraded, Duartenia exhibits coriacious Brachyphyllum-type leaves. Duartenia may be linked to cheirolepid conifers, however, the systematic affinity remains uncertain. The dense wood, characteristic growth pattern and thick, scale like, trichome bearing leaves may be related to ecological conditions that reflect a seasonally dry climate.

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Credneramides A (1) and B (2), two vinyl chloride-containing metabolites, were isolated from a Papua New Guinea collection of cf. Trichodesmium sp. nov. and expand a recently described class of vinyl chloride-containing natural products. The precursor fatty acid, credneric acid (3), was isolated from both the aqueous and organic fractions of the parent fraction as well as from another geographically and phylogenetically distinct cyanobacterial collection (Panama). Credneramides A and B inhibited spontaneous calcium oscillations in murine cerebrocortical neurons at low micro-molar concentrations (1, IC50 4.0 mu M; 2, IC50 3.8 mu M).