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Entre la lengua Francesa y los creoles: Poética Caribe?a
Masello,Laura;
Núcleo , 2010,
Abstract: the issue of language and its decentralizing implications in the literary field represent the great challenge theoreticians and writers from the french-speaking antilles have faced. how has the linguistic issue moved into their discourse, and what position have writers adopted in the face of french-metropolitan literary models? in this paper i adopt édouard glissant?s work as my theoretical framework. he proposes, among other things, that the linguistic concept of creolization be transferred from the cultural to the literary field, as a metaphor for appropriation. he also updates the debate around the aesthetic debt to european models. starting from an understanding of creolization as a métissage, conceived as a process, with results that are essentially unpredictable and whose symbol is the creole language, glissantian poetics build the concept of relation around the region?s multilingualism, the dialectics between oral and written works, and the questioning of literary genres. to illustrate this in the literary field, we will take examples from a corpus consisting of works written and published at the end of the 1980s in guadalupe and martinique.
Cultures de formation: la construction de la compétence de recherche dans des dispositifs de formation permanente
Laura Masello
Synergies Monde , 2012,
Abstract: : Dans le cadre des actions de formation permanente assurées par le Centro de Lenguas Extranjeras (CELEX) de l’Universidad de la República (Uruguay), nous avons inauguré en 2008 des dispositifs destinés à promouvoir la construction conjointe de savoirs par des professeurs travaillant dans des domaines linguistiques divers et provenant donc de cultures formatives différentes. Parmi les modalités mises en place, nous avons développé en 2010 une proposition sous forme de séminaire semi-présentiel, dont la finalité est de réfléchir avec les participants sur la place de la recherche dans leur vie professionnelle. En effet, la formation initiale des enseignants du niveau secondaire en Uruguay ne prévoit pas d’initiation à la recherche; le CELEX s’est donc proposé d’aider à remplr ce vide. Le séminaire s’est déroulé autour de notions telles que les représentations des participants sur le sujet, le débat recherche théorique vs. recherche des enseignants (Galisson & Puren 1999), le processus allant de la pratique réflexive à la théorisation sur la pratique (Zeichner 1993), la construction de la compétence de recherche (Puren 2001, Sturm 2008), entre autres. Dans cet article je présente quelques aspects de cette expérience réunissant deux volets fondamentaux de la vie universitaire: la formation permanente et la recherche.
Hidden dichromatism in the Burrowing Parrot (Cyanoliseus patagonus) as revealed by spectrometric colour analysis
Masello,Juan F.; Lubjuhn,Thomas; Quillfeldt,Petra;
El hornero , 2009,
Abstract: bird colour perception differs fundamentally from that of humans. birds have more cone types in the retina, including uv or violet cones, which enable them to perceive a wider spectral range. thus, human colour perception can be deceiving when assessing functional aspects of bird plumage coloration, such as the intensity of sexual selection. in this study we measured reflectance spectra of different plumage regions of male and female burrowing parrot (cyanoliseus patagonus) individuals. although not obvious to human eyes, spectrometry revealed that adults are sexually dichromatic. plumage regions with structure-based (blue) and structure-psittacofulvin pigment-based (green) coloration differed in achromatic brightness. in contrast, the psittacofulvin-based (red) region differed in spectral shape between the sexes. thus, burrowing parrot is among the growing number of bird species which were formerly classed as sexually monochromatic based on human vision, but which are actually sexually dichromatic.
Distribution Patterns Predict Individual Specialization in the Diet of Dolphin Gulls
Juan F. Masello, Martin Wikelski, Christian C. Voigt, Petra Quillfeldt
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0067714
Abstract: Many animals show some degree of individual specialization in foraging strategies and diet. This has profound ecological and evolutionary implications. For example, populations containing diverse individual foraging strategies will respond in different ways to changes in the environment, thus affecting the capacity of the populations to adapt to environmental changes and to diversify. However, patterns of individual specialization have been examined in few species. Likewise it is usually unknown whether specialization is maintained over time, because examining the temporal scale at which specialization occurs can prove difficult in the field. In the present study, we analyzed individual specialization in foraging in Dolphin Gulls Leucophaeus scoresbii, a scavenger endemic to the southernmost coasts of South America. We used GPS position logging and stable isotope analyses (SIA) to investigate individual specialization in feeding strategies and their persistence over time. The analysis of GPS data indicated two major foraging strategies in Dolphin Gulls from New I. (Falkland Is./Islas Malvinas). Tagged individuals repeatedly attended either a site with mussel beds or seabird and seal colonies during 5 to 7 days of tracking. Females foraging at mussel beds were heavier than those foraging at seabird colonies. Nitrogen isotope ratios (δ15N) of Dolphin Gull blood cells clustered in two groups, showing that individuals were consistent in their preferred foraging strategies over a period of at least several weeks. The results of the SIA as well as the foraging patterns recorded revealed a high degree of specialization for particular feeding sites and diets by individual Dolphin Gulls. Individual differences in foraging behavior were not related to sex. Specialization in Dolphin Gulls may be favored by the advantages of learning and memorizing optimal feeding locations and behaviors. Specialized individuals may reduce search and handling time and thus, optimize their energy gain and/or minimize time spent foraging.
Evaluating the Impact of Handling and Logger Attachment on Foraging Parameters and Physiology in Southern Rockhopper Penguins
Katrin Ludynia, Nina Dehnhard, Maud Poisbleau, Laurent Demongin, Juan F. Masello, Petra Quillfeldt
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0050429
Abstract: Logger technology has revolutionised our knowledge of the behaviour and physiology of free-living animals but handling and logger attachments may have negative effects on the behaviour of the animals and their welfare. We studied southern rockhopper penguin (Eudyptes chrysocome) females during the guard stage in three consecutive breeding seasons (2008/09?2010/11) to evaluate the effects of handling and logger attachment on foraging trip duration, dive behaviour and physiological parameters. Smaller dive loggers (TDRs) were used in 2010/11 for comparison to larger GPS data loggers used in all three seasons and we included two categories of control birds: handled controls and PIT control birds that were previously marked with passive integrative transponders (PITs), but which had not been handled during this study. Increased foraging trip duration was only observed in GPS birds during 2010/11, the breeding season in which we also found GPS birds foraging further away from the colony and travelling longer distances. Compared to previous breeding seasons, 2010/11 may have been a period with less favourable environmental conditions, which would enhance the impact of logger attachments. A comparison between GPS and TDR birds showed a significant difference in dive depth frequencies with birds carrying larger GPS data loggers diving shallower. Mean and maximum dive depths were similar between GPS and TDR birds. We measured little impact of logger attachments on physiological parameters (corticosterone, protein, triglyceride levels and leucocyte counts). Overall, handling and short-term logger attachments (1–3 days) showed limited impact on the behaviour and physiology of the birds but care must be taken with the size of data loggers on diving seabirds. Increased drag may alter their diving behaviour substantially, thus constraining them in their ability to catch prey. Results obtained in this study indicate that data recorded may also not represent their normal dive behaviour.
Prevalence of blood parasites in seabirds - a review
Petra Quillfeldt, Elena Arriero, Javier Martínez, Juan F Masello, Santiago Merino
Frontiers in Zoology , 2011, DOI: 10.1186/1742-9994-8-26
Abstract: From a literature review of hemosporidian prevalence in seabirds, we collated a dataset of 60 species, in which at least 15 individuals had been examined. These data were included in phylogenetically controlled statistical analyses of hemosporidian prevalence in relation to ecological and life-history parameters. Haemoproteus parasites were common in frigatebirds and gulls, while Hepatozoon occurred in albatrosses and storm petrels, and Plasmodium mainly in penguins. The prevalence of Haemoproteus showed a geographical signal, being lower in species with distribution towards polar environments. Interspecific differences in Plasmodium prevalence were explained by variables that relate to the exposure to parasites, suggesting that prevalence is higher in burrow nesters with long fledgling periods. Measures of Plasmodium, but not Haemoproteus prevalences were influenced by the method, with PCR-based data resulting in higher prevalence estimates.Our analyses suggest that, as in other avian taxa, phylogenetic, ecological and life-history parameters determine the prevalence of hemosporidian parasites in seabirds. We discuss how these relationships should be further explored in future studies.Birds are infected by a number of intracellular blood parasites, including Haemosporidia of the genera Plasmodium, Haemoproteus and Leucocytozoon, Haemogregarinidae of the genus Hepatozoon and Piroplasmida of the genus Babesia. These blood parasites can exert important selection pressure on their hosts through effects on survival [1-3], on reproductive success [e.g., [4-8]], on plumage colouration [e.g., [9,10]], with important ecological and evolutionary consequences, such as changes in community structure [e.g., [11]].The rate of infection varies greatly among different bird orders [e.g., [12,13]], but the reasons for the wide taxonomic variation in parasite prevalence or diversity are still poorly understood [14,15]. While some avian taxa are heavily affected, apparent absence or s
Moving polewards in winter: a recent change in the migratory strategy of a pelagic seabird?
Petra Quillfeldt, Juan F Masello, Rona AR McGill, Mark Adams, Robert W Furness
Frontiers in Zoology , 2010, DOI: 10.1186/1742-9994-7-15
Abstract: We studied seasonal movements of Thin-billed prions (Aves, Procellariiformes), breeding at the Subantarctic Falkland/Malvinas Islands, compared with those of Wilson's storm-petrels breeding in the Antarctic South Shetland Islands. The two species showed opposite migratory movements. While Wilson's storm-petrels moved to warmer waters north of the Drake Passage in winter, Thin-billed prions showed a reversed movement towards more polar waters. Carbon stable isotope ratios in recent and historical feathers indicated that poleward winter movements of Thin-billed prions were less common historically (45% in 1913-1915), and have only recently become dominant (92% in 2003-2005), apparently in response to warming sea temperatures.This study shows that pelagic seabirds can rapidly change migration strategies within populations, including migration towards more poleward waters in winter.Migration is thought to be an adaptive strategy, when resources found in the breeding area during the breeding season become scarce during the non-breeding season or climate becomes unfavourable. Animals can then displace to more productive or milder areas [1]. The places animals select for the winter season are usually warmer, e.g. transequatorial to winter in the opposing hemisphere's summer, or further towards the equator within the same hemisphere (latitudinal migration) or lower in the mountains (altitudinal migration). Opposite movements are very rare, and virtually absent in terrestrial birds [1].Many seabirds are too small to carry devices presently available for satellite or GPS tracking. Small pelagic seabirds are difficult to observe in their vast marine ecosystems, and little is known about their distribution and behaviour outside the breeding season. Stable isotopes provide a powerful tool to study movements and trophic position of such birds if tissue grown at different times during the year can be matched to an isotopic gradient across the area of movement [2].Since keratin is
The high Andes, gene flow and a stable hybrid zone shape the genetic structure of a wide-ranging South American parrot
Juan F Masello, Petra Quillfeldt, Gopi K Munimanda, Nadine Klauke, Gernot Segelbacher, H Martin Schaefer, Mauricio Failla, Maritza Cortés, Yoshan Moodley
Frontiers in Zoology , 2011, DOI: 10.1186/1742-9994-8-16
Abstract: Our data show a Chilean origin for this species, with a single migration event across the Andes during the Upper/Late Pleistocene, which gave rise to all extant Argentinean mitochondrial lineages. Analyses suggest a complex population structure for burrowing parrots in Argentina, which includes a hybrid zone that has remained stable for several thousand years. Within this zone, introgression by expanding haplotypes has resulted in the evolution of an intermediate phenotype. Multivariate regressions show that present day climatic variables have a strong influence on the distribution of genetic heterogeneity, accounting for almost half of the variation in the data.Here we show how huge barriers like the Andes and the regional environmental conditions imposed constraints on the ability of a parrot species to colonise new habitats, affecting the way in which populations diverged and thus, genetic structure. When contact between divergent populations was re-established, a stable hybrid zone was formed, functioning as a channel for genetic exchange between populations.Current molecular genetic methods allow the understanding of the genetic structure underlying different populations of a species with previously unforeseen resolution [e.g. [1-3]]. As a result, it is possible to undertake fundamental investigations in ecology and evolution, like the study of the influence of past and current environmental conditions, together with ecological barriers, in shaping the population structure of wild animal species. These studies provide a unique opportunity to understand how species have evolved and how they are organised across landscapes [4]. The constraints that heterogeneous landscapes (e.g. barriers, resource distribution) and environmental conditions (e.g. climate) impose on the ability of animals to colonise new habitats have genetic implications affecting the structure, dynamics and persistence of populations [e.g. [5-9]]. Thus, significant genetic structuring can be expe
Effects of microbial inoculants and amino acid production by-product on fermentation and chemical composition of sugarcane silages
Rodrigues, Paulo Henrique Mazza;Gomes, Rodrigo da Costa;Meyer, Paula Marques;Borgatti, Laura Maria Oliveira;Franco, Fernando Masello Junqueira;Godoy, Gilson Luiz Alves de;
Revista Brasileira de Zootecnia , 2012, DOI: 10.1590/S1516-35982012000600011
Abstract: the objective of this study was to evaluate the chemical composition, fermentation patterns and aerobic stability of sugarcane silages with addition of amino acid production (monosodium glutamate) by-product (apb) and microbial inoculants. mature sugarcane was chopped and ensiled in laboratory silos (n = 4/treatment) without additives (control) and with apb (10 g/kg), pioneer 1174? (pio, 1.0 mg/kg, lactobacillus plantarum + streptoccoccus faecium, pioneer), lalsil cana (2.0 mg/kg, lactobacillus buchineri, lallemand) or mercosil maís 11c33? (1.0 mg/kg, lactobacillus buchineri + lactobacillus plantarum + streptoccoccus faecium, timac agro). fresh silage and silage liquor samples were obtained to assess ph, chemical composition and organic acid concentrations. silage temperature was recorded throughout seven days to evaluate aerobic stability. the addition of apb decreased lactic acid levels, increased ph and n-nh3 and did not alter ethanol, acetic and butyric acids concentrations or dry matter (dm) losses. microbial inoculants enhanced acetic acid levels, although only pioneer 1174? and mercosil maís 11c33? lowered ethanol, butyric acid and dm losses. the addition of apb increased cp content and did not modify dm, soluble carbohydrates contents or in vitro dry matter digestibility. additives did not alter silage maximum temperature or temperature increasing rate; however, pioneer 1174? and mercosil maís 11c33? increased the time elapsed to reach maximum temperature. monosodium glutamate production by-product does not alter fermentation patterns or aerobic stability of sugarcane silages, whereas homofermentative bacteria can provide silages of good quality.
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