988 resultados para Houston, Sam, 1793-1863.
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This study describes the histology and histochemistry of the male reproductive system in Callinectes ornatus, comparing juvenile and adult developmental stages. We also analyzed changes in the gonadosomatic (GSI) and hepatosomatic (HSI) indices, and the weights of the testis and vas deferens during the development. The results showed that all stages, beginning with the juvenile (JUV), through developing (DEV) and mature (MAT) adult males of C. ornatus produce sperm and spermatophores. During development, testicular lobes showed the same characteristics of production and release of sperm into the seminiferous duct. The vas deferens showed little histological and histochemical change in the epithelium in juvenile and adult males. The differences consisted of the larger amount of secretion in MAT males compared to JUV and DEV ones. The chemical composition of the seminal fluid was similar, but MAT males produced a more homogeneous secretion. Morphological and physiological maturation are not synchronized in C. ornatus, since JUV males produced spermatophores similar to those in DEV and MAT males. However, these JUV are not yet able to reproduce, since they still have the abdomen attached to the cephalothoracic sternum. The increase of the GSI during development was significant for MAT males, and is related to the production of sufficient volume of seminal fluid to form the sperm plug in the female seminal receptacle. The HSI decreased from DEV to MAT adult stages, indicating that reserves from the hepatopancreas are used to develop the reproductive system after the pubertal molt.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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The manuscripts of Diarium Surinamicum by Daniel Rolander practically remained ignored and unpublished for over 240 years, till the recent publication of its translation into English, which occurred in 2008. In this, the names of species described and/or cited by Rolander were faithfully retained, hence preserving the indication of them without authorship, for the vast majority. In the present work, all the names of plants that were treated by Rolander in his journal, about 664, including by tradition the fungi and algae, are contextualised in relation to the authorship, reference to the publication of the protologue, pagination of citations/descriptions in the manuscripts and in the published translation, indication of probable misidentifications with possible alternative names, vernacular names, and related literature. Additionally, we searched for the vouchers collected by Rolander, scattered in several herbaria, which have been linked to the probable names and descriptions in the diary. Given the considerable time till the publication of these names, and by the lack of indication of their nomenclatural types in the English version, the great majority of the new species described by Rolander, which would have priority if published in due time, became invalid names according to the ICN. Nevertheless, the list of Rolandrian species here presented, from his work that has finally taken a place in the history of natural sciences, shows that he was also a competent botanist, besides being a skilled entomologist, having recognised and detailedly described many of the Surinamese plants hitherto unknown to science.
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Pós-graduação em História - FCLAS
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The purpose of this paper is to show some characteristics and essential information related to the Brazilian periodicals in the 19th century Revista Popular (1859-1862) and Jornal das Famílias (1863-1878), whose owner was the Frenchman Baptiste Louis Garnier. By that time the proliferation of periodicals attracts attention mainly because several of them had ephemeral existence, in opposition to Garnier’s periodicals which as a whole amount to 19 years in circulation. The research on these periodicals becomes relevant since they are well succeeded publications whose study makes possible the widening of the knowledge on social and cultural aspects of a very important period in Brazilian society.
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This paper reports the results of a comparative study of the development of the larval Echinococcus multilocularis Leuckart, 1863), and associated tissue reaction in naturally and experimentally infected mammals representing 31 species. The histogenesis of the larval cestode was traced in detail in arvicoline rodents of several species, and interspecific differences were defined. In arvicoline rodents, the developing larva exhibited host-specific characteristics within about a month after infection was established. The tissue reaction in Microtus oeconomus was characterized by the production of a large quantity of detritus around the larva, and by the formation of a thick epithelioid zone. In one subspecies, M. oeconomus innuitus, development of the larva was retarded, and the detrital mass was often calcified; in another, M. oeconomus operarius, the detritus rarely became calcified and the larva proliferated more rapidly. In M. pennsylvanicus, the tissue reaction was minimal, and little detritus was present. The characteristics of the tissue reaction in M. montebelli placed it in an intermediate position between the aforementioned species. In Clethrionomys rutilus, a thin epithelioid zone and an outer zone of loose collagenous fibers composed the adventitial layer; exogenous budding was retarded in this vole. A minimal tissue reaction occurred in Lagurus curtatus. In Lemmus spp., larger cysts were characteristic, but areas of small-cystic proliferation were always present. Similar differences in species or subspecies of Citellus and Dicrostonyx were described. Lesions of alveolar bydatid disease in man also were studied. The invasive growth of the larval cestode in the human liver involves a process comparable to small-cystic proliferation in the natural intermediate hosts. Although the later stages of development of the larval cestode are inhibited in man, exogenous proliferation of vesicles continues for the life of the host. The lesion in man was compared with a morphologically similar formation produced by anomalous development of the larval E. granulosus in the bovine liver. The latter is distinguished by the absence of areas of small-cystic proliferation. Non-echinococcal lesions found in the tissues studied, some of which resembled foci caused by the larval E. multilocularis, were briefly discussed.
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Modulo 2 lezioni 25-27
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Reading absurdist plays as hopeful is rare because they are filled with portrayals of horror and despair. However, the tragedy of these plays can allow the audience to experience an atypical kind of hope, often during the final moments of the play. Though the conclusions of the plays are usually ambiguous, this ambiguity and lack of resolutiondoes not preclude hope. The characters persist through their suffering and react in ways that can allow a hopeful affect on the audience. The three absurdist playwrights, Samuel Beckett, Edward Albee, and Sam Shepard, express differing views of the tragic nature of the human condition. However, persistent through all of their work is the ability to view tragedy as having a hopeful affect on the audience. Though the plays do not necessitate a reading of hopefulness, their plays do not preclude this. These absurdist plays do not force the audience into despair, but instead leave open the option of experiencing an expectation and determination for life.