994 resultados para Camels, Fossil.


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In this paper we describe two new genera of philopotine Acroceridae: Schlingeriella irwini gen. et sp. n. (New Caledonia) and Quasi fisheri gen. et sp. n. (Mexico). The Baltic amber species Eulonchiella eocenica Meunier, 1912 is rediagnosed and a neotype designated based on a newly discovered specimen. We also provide a dichotomous key to the world genera of Philopotinae, both living and fossil.

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To elucidate the relationship between forest dynamics and fire frequency pollen percentages and charcoal amounts from a 120 cm long peat core and from samples of modern pollen rain were collected along a transect. The study site in southern Brazil is characterized by a species-rich mosaic of grassland-Araucaria forest. It is of crucial importance for management strategies for conservation to understand the development and maintenance of these vegetation mosaics including their sharp forest-grassland boundaries. During the late Holocene, considerable changes occurred in the area. From Anno Domini (AD) 1360 to 1410, the area was dominated by Campos (grassland) vegetation and fire was very common. From AD 1410 to 1500, Araucaria forest expanded and fire was less frequent. From AD 1500 to 1580, Campos grassland spread and the Araucaria forest ceased its development, apparently due to the increase of fire. From AD 1580 to 1935, after a decrease in fire frequency, Araucaria forest expanded again. From AD 1935 to the present, the Araucaria forest expanded while the Campos area decreased. Fire was very rare in this period. The results indicate a strong interaction of forest expansion, forming a mosaic of Campos and Araucaria forest, and the frequency of fire during the past 600 years. A possible collapse of the indigenous population following the post-Colombian colonization in southern Brazil after about AD 1550 may have caused a great reduction of fire frequency. The introduction of cattle (probably after AD 1780) and the resulting decrease of fire frequency might be the reason for forest expansion. Fire is probably the most important factor controlling the dynamics of the forest-grassland mosaics and the formation of sharp borders between these two vegetation types. (C) 2010 Elsevier B.V. All rights reserved.

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Vegetative and fertile shoots of a shrub-like seed plant from the late Aptian Crato Formation of Brazil are described as Cearania heterophylla Kunzmann, Mohr and Bernardes-de-Oliveira, gen. nov. et sp. nov. Anatomical details of the axes, epidermal features and separate ovulate and pollen producing organs indicate the gymnospermous nature of this plant. The vascular tissue of the axes includes tracheids with bordered pits and fiber tracheids. Vegetative shoots comprising at least three branching orders bear opposite-decussately arranged ovate to lanceolate, dorsiventrally flattened, parallelodromous, rather thick leaves that vary tremendously in size. The amphistomatic leaves bear (brachy-)paracytic stomatal complexes arranged in simple longitudinal files. The ovulate structure is interpreted as a terminally attached single globular ovule/seed surrounded by at least five to six lanceolate bracts. A terminally attached pollen-cone like structure grows on a lateral leafy shoot. The unusual character combination may indicate that the fossils belong to a hitherto unknown group with affinities to ephedroid Gnetales. Sterile shoots formerly often described as Podozamites, Nageiopsis or Lilites that are at least partly congeneric with C. heterophylla Kunzmann, Mohr and Bernardes-de-Oliveira, gen. nov. et sp. nov. had a wide geographic distribution during the Early Cretaceous. (C) 2009 Elsevier B.V. All rights reserved.

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The abundant fossil record of well-preserved Bryozoa in samples from the Tertiary of Victoria and South Australia includes some 'first fossil finds' which are recorded here. Several are of species known from the Recent of the Australian or Indo-West-Pacific regions, but some represent genera with a much wider temporal and geographical range. Of the 11 species illustrated, six are known, or may be inferred, to have inhabited 'sand fauna' environments. Specimens of one species are complete enough to allow its formal description as Chlidoniopsis inopina sp. nov.

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It is commonly assumed that solar hot water systems save energy and reduce greenhouse gas emissions compared to conventional electric and gas hot water systems. Very rarely has the life-cycle energy requirements (including the embodied energy of manufacture) of solar hot water systems been analysed. The extent to which solar hot water systems can save energy compared to conventional electric or gas hot water systems can be shown through a comparative net energy analysis. This method determines the ‘energy payback period’, including consideration of the difference in operational energy savings and energy embodied in the devices relative to a base case. Dr Robert Crawford, Deakin University, Australia presents the results of a net energy analysis that compared solar and conventional hot water systems for a southern (Melbourne) and a northern (Brisbane) Australian climate.

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We tested, using a low starting dilution, sequential serum samples from dromedary camels, sheep and horses collected in Dubai from February/April to October of 2005 and from dromedary camels for export/import testing between Canada and USA in 2000-2001. Using a standard Middle East respiratory syndrome coronavirus (MERS-CoV) neutralization test, serial sera from three sheep and three horses were all negative while sera from 9 of 11 dromedary camels from Dubai were positive for antibodies supported by similar results in a MERS-CoV recombinant partial spike protein antibody ELISA. The two negative Dubai camels were both dromedary calves and remained negative over the 5 months studied. The six dromedary samples from USA and Canada were negative in both tests. These results support the recent findings that infection with MERS-CoV or a closely related virus is not a new occurrence in camels in the Middle East. Therefore, interactions of MERS-CoV at the human-animal interface may have been ongoing for several, perhaps many, years and by inference, a widespread pandemic may be less likely unless significant evolution of the virus allow accelerated infection and spread potential in the human population.

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A diverse and well-preserved fossil wood assemblage is described, for the first time, from the Middle Permian Taerlang Formation and the Upper Permian Quanzijie Formation in the vicinity of the Tianshan Town, Hami City of northwestern China. On the basis of wood microstructure, the fossil woods are classified into three genera and five species, including one new genus: Prototianshanoxylon gen. nov. and two new species: Prototianshanoxylon erdaogouense sp. nov., Prototianshanoxylon hamiense sp. nov. The new genus is characterized by window-like cross-field pitting and mixed tracheid radial wall pitting that suggest a transitional type between araucarioid-type and protopinoid-type pittings.Phytogeographically, the fossil wood assemblage is characterized by an admixture of elements of both temperate Angaran (represented by wood specimens with moderately to well defined growth rings in their secondary xylem) and tropical-subtropical north subregion of the Cathaysian floras (with wood specimens lacking well-defined growth rings). Such a phytogeographically mixed fossil wood assemblage is interpreted to represent a transitional and complex climate condition between a cool temperate and tropical to subtropical zones, showing both seasonal variation and unstable climate conditions. Previously, similarly mixed floras have already been found to exist widely in northern China ranging in age from Early to Late Permian, but the mechanisms thought to be responsible for their formation were varied and remain controversial. In this study, the formation of these mixed Permian floras of North China is linked to the closure of the Tianshan-Hingan seaway coupled with the collision and amalgamation of Siberia with North China and the Tarim block, in a manner much like closing a pair of scissors with the closure of the seaway proceeding gradually and progressively from west to the east.

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O Centro de Porto Alegre (Brasil) caracteriza-se pela presença de vendedores de rua desde o século XVIII. Hoje, contudo, essa forma de comércio informal assume proporções extraordinárias, constituindo-se um fenômeno global relacionado à produção e comercialização de pirataria, consumida generalizadamente em todas as camadas sociais. O universo desta pesquisa são os camelôs e sacoleiros regularizados que trabalham na Praça XV de Novembro da capital gaúcha e comercializam mercadorias contrabandeadas de Ciudad del Este (Paraguai), trazidas por eles próprios. A atuação dos camelôs no espaço público envolve uma permanente negociação - ora pacífica, ora conflituosa - com o poder público, lojistas, meios de comunicação e vendedores de rua em situação irregular. Afora as dificuldades do trabalho de rua e a competitividade do ofício, os comerciantes estudados formam suas redes de relações (sejam elas de vizinhança, de parentesco ou de companheirismo de viagem) pautadas pela presença constante da solidariedade e lealdade - códigos simbólicos que dão sustentação ao trabalho cotidiano, conferindo sentido ao trabalho e à vida social. Procura-se, com isso, fornecer uma visão ampla do universo estudado, mostrando várias de suas facetas, acompanhadas ao longo de uma etnografia que aconteceu tanto em Porto Alegre, quanto na fronteira do Brasil com o Paraguai.

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The phenomenon of the informality has been common in the quarrels that involve Sciences Social and Human. First for not corresponding to a temporary and isolated phenomenon, and on the other hand for dealing with a presente situation in the majority of the Brazilian urban centers. In Cuiabá municipality, the alternative commerce appears as a social answer to the problems caused for the economic crisis of the country and seems to be deep-rooted to the urban landscape. This assignment angles was the street peddlers, in special that ones who develop their in a specific location on lowered of Cuiabá. Researches pretending to fill a blank of information about this subject involve theoritical and empirical levels. The theory searched to raise in a generalized manner given pertinent the informality and the pratical level through field research searched to analyze excellent aspects on the economic and occupational situation of a composed sample for two hundred and theree workers who develope the pratical one of the informal commerce in Shopping Popular in Cuiaba/MT. The analysis of gotten data alllowed to appreciate some excellent aspects with regard to the activity os the peddler, as: origni, formation, income, perspectives with regard to activity among others. In las analysis it still alllowed to verify the factors that condition the permanence these workers in this type of informal activity

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Vendoconularia triradiata Ivantsov and Fedonkin, recently described from Vendian (latest Proterozoic) strata of Russia, has been interpreted as a six-sided conulariid cnidarian. However, comparison of published illustrations of V. triradiata with Palaeozoic conulariids suggests that certain key features of the anatomy of V. triradiata should be reinterpreted. Specifically, features previously homologized with the corners of conulariid thecae may actually be homologous to the conulariid midlines. Under this new interpretation, the corners of the Vendoconularia theca were sulcate, and the midline of each face was non-sulcate and flanked by a pair of low internal carinae. This alternative set of hypotheses of homology makes the argument for a conulariid affinity for Vendoconularia stronger.