975 resultados para De Hostos, Eugenio María (1839-1903)


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Aim To examine the effect of climate change on the occurrence and distribution of Pipistrellus nathusii (Nathusius' pipistrelle) in the United Kingdom (UK).Location We modelled habitat and climatic associations of P. nathusii in the UK and applied this model to the species' historical range in continental Europe.Methods A binomial logistic regression model was constructed relating the occurrence of P. nathusii to climate and habitat characteristics using historical species occurrence records (1940-2006) and CORINE land cover data. This model was applied to historical and projected climate data to examine changes in suitable range (1940-2080) of this species. We tested the predictive ability of the model with known records in the UK after 2006 and applied the model to the species' known range in Europe.Results The distribution of P. nathusii was related positively to the area of water bodies, woodland and small areas of urbanization, and negatively related to the area of peat/heathland. Species records were associated with higher minimum temperatures, low seasonal variation in temperature and intermediate rainfall. We found that suitable areas have existed in the UK since the 1940s and that these have expanded. The model had high predictive power when applied to new records after 2006, with a correct classification rate of 70%, estimated by receiver operating characteristic analysis. Based on climate projections, our model suggests a potential twofold increase in the area suitable for P. nathusii in the UK by 2050. The single most influential climate variable contributing to range increase was the projected increase in minimum temperature. When applied to Europe, the model predictions had best predictive capability of known records in western areas of the species' range, where P. nathusii is present during the winter.Main conclusions We show that a mobile, migratory species has adapted its range in response to recent climate change on a continental scale. We believe this may be the first study to demonstrate a case of range change linked to contemporary climate change in a mammal species in Europe.

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We describe the most westerly known maternity colony of Nathusius' pipistrelle bats (Pipistrellus nathusii). The bats were identified by using morphometric measurements and analysis of time-expanded echolocation and social calls. The roost, containing approximately 150 individuals, was located in a mid 19th century farm stable block and store house situated in parkland in County Antrim, Northern Ireland. The roost was visited on 30 April, I May and 22 June 1997. Over this period, 11 bats were caught: one adult male, five pregnant females, four lactating females and a juvenile male. Direct observation of behaviour patterns suggests that mating groups of P. nathusii may occur in Ireland as late as May. The migratory nature of this species is discussed.

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The Escherichia coli transcriptional regulator MarA affects functions that include antibiotic resistance, persistence, and survival. MarA functions as an activator or repressor of transcription utilizing similar degenerate DNA sequences (marboxes) with three different binding site configurations with respect to the RNA polymerase-binding sites. We demonstrate that MarA down-regulates rob transcripts both in vivo and in vitro via a MarA-binding site within the rob promoter that is positioned between the -10 and -35 hexamers. As for the hdeA and purA promoters, which are repressed by MarA, the rob marbox is also in the "backward" orientation. Protein-DNA interactions show that SoxS and Rob, like MarA, bind the same marbox in the rob promoter. Electrophoretic mobility shift analyses with a MarA-specific antibody demonstrate that MarA and RNA polymerase form a ternary complex with the rob promoter DNA. Transcription experiments in vitro and potassium permanganate footprinting analysis show that MarA affects the RNA polymerase-mediated closed to open complex formation at the rob promoter.

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The Escherichia coli MarA protein mediates a response to multiple environmental stresses through the activation or repression in vivo of a large number of chromosomal genes. Transcriptional activation for a number of these genes has been shown to occur via direct interaction of MarA with a 20-bp degenerate asymmetric "marbox" sequence. It was not known whether repression by MarA was also direct. We found that purified MarA was sufficient in vitro to repress transcription of both purA and hdeA. Transcription and electrophoretic mobility shift experiments in vitro using mutant promoters suggested that the marbox involved in the repression overlapped the -35 promoter motif and was in the "backward" orientation. This organization contrasts with that of the class II promoters activated by MarA, in which the marbox also overlaps the -35 motif but is in the "forward" orientation. We conclude that MarA, a member of the AraC/XylS family, can act directly as a repressor or an activator, depending on the position and orientation of the marbox within a promoter.

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Fish belonging to the genus Macroramphosus are distributed throughout the Atlantic, Indian and PaciWc oceans. Some authors consider this genus monotypic, Macroramphosus scolopax being the only valid species. Other authors consider (based on several morphological and ecological characters) that another species (Macroramphosus gracilis) exists and occurs frequently in sympatry with the Wrst one. Intermediate forms are also reported in literature. In this paper, using the mitochondrial control region and the nuclear Wrst S7 intron markers, we failed to Wnd genetic diVerences between individuals considered to belong to both species as well as the intermediate forms. Our results suggest that in the northeastern Atlantic, Macroramphosus is represented by a single species, M. scolopax, with diVerent morphotypes interbreeding in the sampling areas.

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abstract : Taking as a starting point the association between embroidery and language conveyed by the Greek myth of Filomela and Procne, this article examines the relationship between social status and ornaments like embroidery and lace. In order to illustrate this relationship an example is selected form the letters exchanged between the Marquise of Alorna and her Father where a connection is established between the production of these 'feminine' crafts, women's culture and womens writing, in the XVIIIth Century

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O tema de análise neste trabalho é o fenómeno da transculturação em Angola no século XIX. É uma pesquisa centrada na história de vida do sertanejo António Francisco Ferreira da Silva Porto, entre 1839 e 1890, no meio sócio-cultural umbundu. Transculturação é um termo polissémico que integra aspectos da aculturação sendo aqui utilizado no âmbito da História de vida de Silva Porto. Descodifica-se a narrativa no Diário de viagem que Silva Porto redigiu acerca da sua percepção sobre África e do seu percurso de convivência no processo da sua integração em África Central. A transculturação está nessa narrativa e reflecte múltiplas vivências, sobretudo, a visão social do “Outro” em relação à sua própria identidade de origem. Silva Porto é encarado neste trabalho como sujeito, autor, actor principal e protagonista do fenómeno da transculturação, na região do Viye em Angola. Identificaram-se cinco variáveis do fenómeno transcultural, presentes na trajectória de Silva Porto: o casamento, a língua, as viagens, a alimentação e a religião, com particular destaque para o casamento enquanto variável determinante na integração de Silva Porto na sociedade umbundu. Estas variáveis são apresentadas num iceberg de transculturação de Silva Porto que, por sua vez, permitem avaliar as diferenças culturais e o cruzamento entre as culturas sob um processo de alteridade, em confluência com um olhar distanciado. É um estudo onde perpassa o crivo das construções e representações de Silva Porto tendo em conta o seu contexto cultural de origem, predominantemente português, a sua adaptação e inserção nas culturas africanas, particularmente nas práticas sócio-culturais umbundu. A questão de partida deste estudo foi: Quem é Silva Porto depois de 50 anos de vivências em Angola?

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Com esta investigação pretende-se caracterizar a relação indissociável entre História e Fotografia, reconhecendo as múltiplas formas de manipulação e respectivos mecanismos de hierarquização de poder, que não apenas determinam o desenvolvimento da sua produção, arquivo e recepção, como desvendam uma constelação de ligações disciplinares, técnicas e políticas que potenciam e moldam o seu sentido. Esta problemática é analisada no contexto português, a partir das práticas de exposição, publicação e colecção fotográfica e consequente ajuste do discurso teórico e crítico nas décadas de 1980 e 1990, adoptando como eixo de pesquisa o trabalho de investigação e historiografia desenvolvido entre 1973 e 1998 por António Sena e, especificamente, o modo como aplica a História (de um meio) como hiperdocumento. O filme Olho de Vidro, uma História da Fotografia (1982), realizado por António Sena e Margarida Gil, as iniciativas fotográficas desenvolvidas pela associação ether/vale tudo menos tirar olhos entre 1982 e 1994, a criação da base de dados Luzitânia/ ether pix database e as publicações Uma História de Fotografia (1991) e História da Imagem Fotográfica em Portugal, 1839-1997 (1998) da autoria de António Sena, formam o corpus do nosso estudo de caso.

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Claes Wilhelm Gyldén (1802-1872) oli maanmittauksen ja metsänhoidon ylihallituksen ylitirehtööri vuosina 1854-72. Ylitirehtööri omisti paljon aikaansa metsänhoidon ja maanjakotoiminnan lisäksi myös maamme kartastotoiminnalle. Hän julkaisi vuonna 1853 Suomenmaan korko-kartan, joka on maailman ensimmäisiä korkeusvyöhykekarttoja. Myös Suomen yleiskartan 1:400 000 (Karta över Finland) ensimmäisen painoksen karttalehdet painettiin vuosina 1864-1872 hänen johtajakaudellaan. Vuosina 1837-1843 toimiessaan maanmittausinsinöörinä maanmittaushallituksessa C. W. Gyldén julkaisi Suomen kaikkien silloisten kaupunkien kaupunkikartat, yhteensä 31 karttalehteä. Nämä asemakaavakartat painettiin kaikki samassa koossa 50,8 x 65,9 cm. Tästä johtuen karttojen mittakaavat vaihtelivat asteikkojen 1:3200 – 1:10000 välillä. Kaupungin asemakaavan lisäksi jokaisessa kartassa on yleissilmäyskartta, julkisten rakennusten luettelo sekä niiden sijainti. Lisäksi hän julkaisi vuonna 1844 näiden kaupunkien historiaa ja tilastotietoja kuvaavan selityskirjan.