993 resultados para Williamson, Robert Wood, 1856-1932.


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Foram feitas observações no laboratório e no campo, em Belo Horizonte, MG, Brasil, com a finalidade de se obter informações biológicas e ecológicas sobre Pomacea haustrum (Reeve, 1856), molusco pilídeo, competidor-predador de hospedeiros intermediários de Schistosoma mansoni Sambon 1907.

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Na localidade de Baldim, MG, Brasil, foram introduzidos, em agosto de 1972, 5.421 exemplares de Pomacea haustrum (Prosobranchia, Pilidae) em 5 córregos e 2 valas, nos quais predominavam Biomphalaria glabrata (Say, 1818) e, secundariamente, B. straminea (Dunker, 1848). Entre 1968 e 1971, os índices de infecção da espécie B. glabrata por Schistosoma mansoni oscilaram de 2,1% a 11,9%. Em nenhum momento foram capturados B. straminea liberando cercárias daquele trematódeo. Após a introdução do pilídeo, apenas uma única vez detectou-se 2 (0,8%) B. glabrata positivas. Observou-se decréscimo populacional de planorbineos e aumento de densidade de pomácea até 20,0 e 121,6 exemplares/m² em córregos e valas, respectivamente. A estimativa da densidade de F. haustrum foi feita através do método dos "quadrats". Foram coletados, de junho de 1968 a julho de 1972, 65,2% (1.526) dos planorbíneos. Porém, após a introdução do predador-competidor, foram registrados os seguintes dados: 1976, 15% (352); em 1977, 16,1% (377) e, em 1978, apenas 3,7% (87) do total dos exemplares capturados. As pomáceas, transferidas do ambiente lenítico (Sete Lagoas, MG), adaptaram-se às coleções lóticas de Baldim e foram capazes de substituir as populações originais de B. glabrata em vários biótopos, ou tornaram-se, pelo menos, dominantes, sem danos visíveis para os novos ecossistemas. Acredita-se que em outras situações análogas, Pomacea haustrum (Reeve, 1956) - e, por extensão, P. lineata (Spix, 1827), P. canaliculata (Lamark, 1822) e outras do mesmo táxon - poderão ser utilizadas, com sucesso, no controle biológico dos hospedeiros intermediários de Schistosoma mansoni.

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Foi acompanhado em laboratório o controle de planorbíneos (Biomphalaria straminea Dunker, 1848; B. tenagophila Orbigny, 1835 e B. glabrata Say, 1818), hospedeiros intermediários da esquistossomose mansoni, através da predação de suas desovas pelo pilídeo Pomacea haustrum Reeve, 1856. De 829 desovas ovipostas por B. straminea, 203 (24,5%) foram expostas a 10 exemplares de P. haustrum; destas, 200 (98,3%) foram predadas. De 892 desovas ovipostas por B. tenagophia, 201 (22,5%) foram expostas a 10 exemplares de P. haustrum; destas, 194 (97,0%) foram predadas. De 1.300 desovas ovipostas por B. glabrata, 657 (50,5%) foram expostas a 10 exemplares de P. haustrum sendo totalmente predadas. Paralelamente, procurou-se observar as possíveis interações ocorridas entre pomáceas e planorbíneos quando da coabitação do mesmo aquário.

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Dealing with ancient manuscript or old printed texts often constitutes a difficult task, especially to philologists and editors, for two main reasons: the precarious state of preservation of the documents and the uncertainty regarding their origin, authenticity and authorship. These problems are aggravated by spurious versions, due to the publication of truncated works, poorly supervised miscellanies and non-authorised editions. Sir Robert Sidney’s literary text constitutes an exception amidst such vicissitudes, once the original corpus is wholly contained in a notebook exhibiting the organisation and unity conceived by the author himself. Today, there is no evidence that any loose poems, either autograph or copied by amanuenses, were in circulation among members of the Elizabethan court society. The notebook was kept in private collections for four centuries, which probably explains why it was so well preserved. In fact, only in 1984 would P.J. Croft’s fine edition bring the youngest Sidney’s Poems into light. In this work, I approach Croft’s perceptive, accurate philological study that eventually rescued from oblivion a remarkable piece both of the Elizabethan lyric poetry and of the English Renaissance, and, at the same time, look into Robert Sidney’s peculiar, careful and original formatting of his own autograph manuscript.

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One Plus Sequential Air Sampler—Partisol was placed in a small village (Foros de Arrão) in central Portugal to collect PM10 (particles with an aerodynamic diameter below 10 μm), during the winter period for 3 months (December 2009–March 2010). Particles masses were gravimetrically determined and the filters were analyzed by instrumental neutron activation analysis to assess their chemical composition. The water-soluble ion compositions of the collected particles were determined by Ion-exchange Chromatography. Principal component analysis was applied to the data set of chemical elements and soluble ions to assess the main sources of the air pollutants. The use of both analytical techniques provided information about elemental solubility, such as for potassium, which was important to differentiate sources.

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This paper concerns the study of biocides application in old timber structures of maritime pine (Pinus pinaster Ail.), previously impregnated with other products. A method was developed in laboratory to determine in situ the penetration depth of a product applied superficially. As initial treatment, three traditional products for sawn timber for buildings were used and, for new treatments, two newer, more environmentally benign products were used. Their ability to penetrate the pre-treated surfaces was evaluated after 1, 2 and 3 applications at 24 hours intervals and the results obtained are presented. Finally, the applicability of the developed test to the in-situ evaluation of timber structures is also discussed.

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O tema sobre o qual me proponho escrever insere-se no âmbito da 'tradução intersemiótica', já que se trata de uma análise comparativa da obra Der Sturz des Ikarus, de Pieter Brueghel, e do poema Schimmernde Inselchen im Meer, de Robert Walser, em que estamos perante um exemplo flagrante de transposição de uma obra pictórica para a escrita. No artigo, darei, ainda, especial enfoque à questão de aquele quadro representar, também ele, um exemplo de 'tradução intersemiótica' (neste caso, uma passagem da palavra às artes plásticas), uma vez que Brueghel faz, nele, uma recontextualização do mito de Ícaro, ao transpor para a tela um poema de Ovídio (estamos, assim, mais uma vez, perante um exemplo de mudança de medium). Dado que a questão da 'tradução intersemiótica' se inscreve numa outra, mais vasta ainda, que éa da intertextualidade, tentarei enquadrar uma na outra, tecendo, na introdução do artigo e, sempre que oportuno, ao longo do mesmo, algumas considerações breves sobre a função significante do mitema, as metamorfoses do mito e o papel do mito no 'diálogo intermedial das artes' ao longo dos tempos. Nesta análise comparativa, parto do pressuposto de estarmos, em qualquer tradução, face a um acto de re-escrita, pelo que há que reflectir, particularmente no caso da 'tradução intersemiótica', sobre a (nova) dimensão interpretativa conferida pelo processo de transposição mediática

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The kraft pulps produced from heartwood and sapwood of Eucalyptus globulus at 130 degrees C, 150 degrees C, and 170 degrees C were characterized by wet chemistry (total lignin as sum of Klason and soluble lignin fractions) and pyrolysis (total lignin denoted as py-lignin). The total lignin content obtained with both methods was similar. In the course of delignification, the py-lignin values were higher (by 2 to 5%) compared to Klason values, which is in line with the importance of soluble lignin for total lignin determination. Pyrolysis analysis presents advantages over wet chemical procedures, and it can be applied to wood and pulps to determine lignin contents at different stages of the delignification process. The py-lignin values were used for kinetic modelling of delignification, with very high predictive value and results similar to those of modelling using wet chemical determinations.

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The purpose of this work was to assess the acute toxicity on male mice to a chromated copper arsenate (CCA) solution, a widespread wood preservative used in building industry until 2002. Animals were subcutaneously injected with CCA (7.2 mg/kg arsenic and 10.2 mg/kg chromium per body weight), CrO3 (10.2 mg/kg), As2O5 (7.2 mg/kg) and NaCl (0.9%) per se, during 48 h and 96 h, for histopathology, histochemistry, chromium and arsenic analysis. The results showed some histopathological changes within renal tubules lumen of CCA exposed animals (during 48 h, and 96 h), and CrO3 (for the period of 96 h). Furthermore, the renal levels of arsenic and chromium in treated animals were statistically more evident than controls. Although, the same contents of pentavalent arsenic and hexavalent chromium were injected into treated animals with CCA and with the prepared solutions of As2O5 and CrO3, a different distribution of the pattern of these compounds was observed in kidneys.

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Chromium copper arsenate(CCA)was used for the protection of wood building material suntil the restriction by EPA in2002. During a short period of time 14–24h,a comparative nephrotoxicity study was performed regarding the effects of CCA and its compounds per se. Histopathological and histochemical features were correlated with the concentration of the total arsenic and chromium in mice kidney. Animals were subcutaneously injected with CCA(7.2mg/kg arsenic and 10.2mg/kg chromium per body weight), CrO3 (10.2 mg/kg),As2O5 (7.2 mg/kg)andNaCl(0.9%) per se. The histopathological examination of the renal sections evidenced acute tubular necrosis in the groups of animals exposed to CCA(in both periods of time). Although the same contents of pentavalent arsenic and hexavalent chromium were injected in treated animals with CCA and with the prepared solutions of As2O5 and CrO3, the arsenic concentration on kidneys of CCA-exposed animals was much higher than those in animals exposed to As2O5 (32- and28-fold higher at 14 and 24h,respectively). However,the elimination of chromium seems to occur similarly in the kidneys of animals treated with CCA and CrO3 per se. Interactions among the components of CCA result in a marked decrease of the ability of kidney to eliminate simultaneously both analytes.The nephrotoxicity of CCA was higher than its components per se, evidencing a possible synergetic effect.

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The legacy of nineteenth century social theory followed a “nationalist” model of society, assuming that analysis of social realities depends upon national boundaries, taking the nation-state as the primary unit of analysis, and developing the concept of methodological nationalism. This perspective regarded the nation-state as the natural - and even necessary - form of society in modernity. Thus, the constitution of large cities, at the end of the 19th century, through the intense flows of immigrants coming from diverse political and linguistic communities posed an enormous challenge to all social research. One of the most significant studies responding to this set of issues was The Immigrant Press and its Control, by Robert E. Park, one of the most prominent American sociologists of the first half of the 20th century. The Immigrant Press and its Control was part of a larger project entitled Americanization Studies: The Acculturation of Immigrant Group into American Society, funded by the Carnagie Corporation following World War I, taking as its goal to study the so-called “Americanization methods” during the 1920s. This paper revisits that particular work by Park to reveal how his detailed analysis of the role of the immigrant press overcame the limitations of methodological nationalism. By granting importance to language as a tool uniting each community and by showing how the strength of foreign languages expressed itself through the immigrant press, Park demonstrated that the latter produces a more ambivalent phenomenon than simply the assimilation of immigrants. On the one hand, the immigrant press served as a connecting force, driven by the desire to preserve the mother tongue and culture while at the same time awakening national sentiments that had, until then, remained diffuse. Yet, on the other hand, it facilitated the adjustment of immigrants to the American context. As a result, Park’s work contributes to our understanding of a particular liminal moment inherent within many intercultural contexts, the space between emigrant identity (emphasizing the country of origin) and immigrant identity (emphasizing the newly adopted country). His focus on the role played by media in the socialization of immigrant groups presaged later work on this subject by communication scholars. Focusing attention on Park’s research leads to other studies of the immigrant experience from the same period (e.g., Thomas & Znaniecki, The Polish Peasant in Europe and America), and also to insights on multi-presence and interculturality as significant but often overlooked phenomena in the study of immigrant socialization.

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When timber elements in heritage buildings are moderately degraded by fungi and assuming underlying moisture problems have been solved, two actions can be taken: i) use a biocide to stop fungal activity; ii) consolidate the degraded elements so that the timber keeps on fulfilling its structural and decorative functions. The aim of this work is to investigate the mechanical performance of maritime pine wood degraded by fungi after being treated with a biocide followed by impregnation with a polymer product. Three commercially available products were used: a boron water-based biocide, an acrylic consolidant and an epoxy-based consolidant. Treated and consolidated specimens were subjected to mechanical tests: axial compression test (NP 618), static surface hardness (ISO 3350) and bending test (NP 619). Sets of replicates were subjected to an evaporation ageing test (EN 73) after application of the products and also tested for mechanical behaviour. An increase in mechanical strength was observed for both consolidants with no significant influence from the previous use of biocide product. The specimens subjected to ageing showed a slightly better general mechanical performance.