923 resultados para Aesthetic and ideological evolution
Resumo:
Si bien el '80 ha sido trabajado y leÃdo desde distintos contextos socio históricos y literarios, la continuidad y resignificación de su 'corpus' y sus legados, deja abierto un espacio para la crÃtica, con una cantidad considerable de autores que han sido lateralizados, en muchos casos, por lecturas convencionales. Enrique Loncán es un autor periférico de comienzos del siglo XX al igual que Eduardo Holmberg, a punto tal que su obra Olimpio Pitango de Monalia recién se publicó en el año 1994. Según Arturo Cancela, 'Con Enrique Loncán, se cierra para siempre el ciclo de la literatura mundana comenzado por la generación del 80, en cuyos cánones se inscriben su personalidad, sus gustos y su literatura.? Heredero o epÃgono de escritores como Mansilla en el Sud América, de Lucio V. López, de Eduardo Wilde y de Miguel Cané, pone en práctica su versatilidad discursiva frecuentando el periodismo, la oratoria, la polÃtica y la literatura, a la vez que se desempeña en la cátedra universitaria, el Congreso Nacional y la diplomacia. Eduardo Holmberg, por otra parte, pertenece a la saga de los escritores conocidos a medias y muchas veces, por esta misma causa, ha sido motivo de una simplificación oportunista de su significación, sujeto a una lectura rápida, proclive a juicios no del todo probados. La Tesis está estructurada en dos partes y cada una tiene como eje el estudio de uno de los dos autores citados. La primera está dedicada a la obra de Enrique Loncán, particularmente Palabras de la derrota [1919], He dicho [Brindis y discursos] [1925] y Aldea Millonaria [1933], y la segunda aborda dos conferencias 'Carlos Alberto Darwin', 'Pinceladas descriptivas' y los dos últimos textos escritos por Eduardo Holmberg, Lin Calel (1910) y Olimpio Pitango de Monalia [1912-1915]. El tÃtulo de la Tesis, Permanencia y superación del '80 en dos escritores de 'entre-siglos', adelanta sus dos hipótesis centrales: la 'permanencia' o continuidad poética e ideológica del '80 en los trabajos de Loncán, y la 'superación' del mismo perÃodo por la práctica de escritura de Eduardo Holmberg. El cruce de ambos autores y sus respectivas obras pone de relieve un doble movimiento, el regreso al pasado por parte de quien desarrolló su carrera literaria durante los primeros cuarenta años del siglo XX [Loncán], y la evolución hacia el futuro de Holmberg que se desarrolló literariamente a lo largo del '80. Este doble movimiento 'el retroceso hacia las fuentes por parte de Loncán y el 'progreso' rupturista de Holmberg- mantiene una relación dialéctica con la historia social y polÃtica del paÃs en el primer caso, y una relación con la historia y con la filosofÃa de la historia en el segundo, sobre todo en Olimpio Pitango de Monalia, en la medida en que deconstruye la historiografÃa liberal oficial
Resumo:
Si bien el '80 ha sido trabajado y leÃdo desde distintos contextos socio históricos y literarios, la continuidad y resignificación de su 'corpus' y sus legados, deja abierto un espacio para la crÃtica, con una cantidad considerable de autores que han sido lateralizados, en muchos casos, por lecturas convencionales. Enrique Loncán es un autor periférico de comienzos del siglo XX al igual que Eduardo Holmberg, a punto tal que su obra Olimpio Pitango de Monalia recién se publicó en el año 1994. Según Arturo Cancela, 'Con Enrique Loncán, se cierra para siempre el ciclo de la literatura mundana comenzado por la generación del 80, en cuyos cánones se inscriben su personalidad, sus gustos y su literatura.? Heredero o epÃgono de escritores como Mansilla en el Sud América, de Lucio V. López, de Eduardo Wilde y de Miguel Cané, pone en práctica su versatilidad discursiva frecuentando el periodismo, la oratoria, la polÃtica y la literatura, a la vez que se desempeña en la cátedra universitaria, el Congreso Nacional y la diplomacia. Eduardo Holmberg, por otra parte, pertenece a la saga de los escritores conocidos a medias y muchas veces, por esta misma causa, ha sido motivo de una simplificación oportunista de su significación, sujeto a una lectura rápida, proclive a juicios no del todo probados. La Tesis está estructurada en dos partes y cada una tiene como eje el estudio de uno de los dos autores citados. La primera está dedicada a la obra de Enrique Loncán, particularmente Palabras de la derrota [1919], He dicho [Brindis y discursos] [1925] y Aldea Millonaria [1933], y la segunda aborda dos conferencias 'Carlos Alberto Darwin', 'Pinceladas descriptivas' y los dos últimos textos escritos por Eduardo Holmberg, Lin Calel (1910) y Olimpio Pitango de Monalia [1912-1915]. El tÃtulo de la Tesis, Permanencia y superación del '80 en dos escritores de 'entre-siglos', adelanta sus dos hipótesis centrales: la 'permanencia' o continuidad poética e ideológica del '80 en los trabajos de Loncán, y la 'superación' del mismo perÃodo por la práctica de escritura de Eduardo Holmberg. El cruce de ambos autores y sus respectivas obras pone de relieve un doble movimiento, el regreso al pasado por parte de quien desarrolló su carrera literaria durante los primeros cuarenta años del siglo XX [Loncán], y la evolución hacia el futuro de Holmberg que se desarrolló literariamente a lo largo del '80. Este doble movimiento 'el retroceso hacia las fuentes por parte de Loncán y el 'progreso' rupturista de Holmberg- mantiene una relación dialéctica con la historia social y polÃtica del paÃs en el primer caso, y una relación con la historia y con la filosofÃa de la historia en el segundo, sobre todo en Olimpio Pitango de Monalia, en la medida en que deconstruye la historiografÃa liberal oficial
Resumo:
Si bien el '80 ha sido trabajado y leÃdo desde distintos contextos socio históricos y literarios, la continuidad y resignificación de su 'corpus' y sus legados, deja abierto un espacio para la crÃtica, con una cantidad considerable de autores que han sido lateralizados, en muchos casos, por lecturas convencionales. Enrique Loncán es un autor periférico de comienzos del siglo XX al igual que Eduardo Holmberg, a punto tal que su obra Olimpio Pitango de Monalia recién se publicó en el año 1994. Según Arturo Cancela, 'Con Enrique Loncán, se cierra para siempre el ciclo de la literatura mundana comenzado por la generación del 80, en cuyos cánones se inscriben su personalidad, sus gustos y su literatura.? Heredero o epÃgono de escritores como Mansilla en el Sud América, de Lucio V. López, de Eduardo Wilde y de Miguel Cané, pone en práctica su versatilidad discursiva frecuentando el periodismo, la oratoria, la polÃtica y la literatura, a la vez que se desempeña en la cátedra universitaria, el Congreso Nacional y la diplomacia. Eduardo Holmberg, por otra parte, pertenece a la saga de los escritores conocidos a medias y muchas veces, por esta misma causa, ha sido motivo de una simplificación oportunista de su significación, sujeto a una lectura rápida, proclive a juicios no del todo probados. La Tesis está estructurada en dos partes y cada una tiene como eje el estudio de uno de los dos autores citados. La primera está dedicada a la obra de Enrique Loncán, particularmente Palabras de la derrota [1919], He dicho [Brindis y discursos] [1925] y Aldea Millonaria [1933], y la segunda aborda dos conferencias 'Carlos Alberto Darwin', 'Pinceladas descriptivas' y los dos últimos textos escritos por Eduardo Holmberg, Lin Calel (1910) y Olimpio Pitango de Monalia [1912-1915]. El tÃtulo de la Tesis, Permanencia y superación del '80 en dos escritores de 'entre-siglos', adelanta sus dos hipótesis centrales: la 'permanencia' o continuidad poética e ideológica del '80 en los trabajos de Loncán, y la 'superación' del mismo perÃodo por la práctica de escritura de Eduardo Holmberg. El cruce de ambos autores y sus respectivas obras pone de relieve un doble movimiento, el regreso al pasado por parte de quien desarrolló su carrera literaria durante los primeros cuarenta años del siglo XX [Loncán], y la evolución hacia el futuro de Holmberg que se desarrolló literariamente a lo largo del '80. Este doble movimiento 'el retroceso hacia las fuentes por parte de Loncán y el 'progreso' rupturista de Holmberg- mantiene una relación dialéctica con la historia social y polÃtica del paÃs en el primer caso, y una relación con la historia y con la filosofÃa de la historia en el segundo, sobre todo en Olimpio Pitango de Monalia, en la medida en que deconstruye la historiografÃa liberal oficial
Resumo:
Si bien el '80 ha sido trabajado y leÃdo desde distintos contextos socio históricos y literarios, la continuidad y resignificación de su 'corpus' y sus legados, deja abierto un espacio para la crÃtica, con una cantidad considerable de autores que han sido lateralizados, en muchos casos, por lecturas convencionales. Enrique Loncán es un autor periférico de comienzos del siglo XX al igual que Eduardo Holmberg, a punto tal que su obra Olimpio Pitango de Monalia recién se publicó en el año 1994. Según Arturo Cancela, 'Con Enrique Loncán, se cierra para siempre el ciclo de la literatura mundana comenzado por la generación del 80, en cuyos cánones se inscriben su personalidad, sus gustos y su literatura.? Heredero o epÃgono de escritores como Mansilla en el Sud América, de Lucio V. López, de Eduardo Wilde y de Miguel Cané, pone en práctica su versatilidad discursiva frecuentando el periodismo, la oratoria, la polÃtica y la literatura, a la vez que se desempeña en la cátedra universitaria, el Congreso Nacional y la diplomacia. Eduardo Holmberg, por otra parte, pertenece a la saga de los escritores conocidos a medias y muchas veces, por esta misma causa, ha sido motivo de una simplificación oportunista de su significación, sujeto a una lectura rápida, proclive a juicios no del todo probados. La Tesis está estructurada en dos partes y cada una tiene como eje el estudio de uno de los dos autores citados. La primera está dedicada a la obra de Enrique Loncán, particularmente Palabras de la derrota [1919], He dicho [Brindis y discursos] [1925] y Aldea Millonaria [1933], y la segunda aborda dos conferencias 'Carlos Alberto Darwin', 'Pinceladas descriptivas' y los dos últimos textos escritos por Eduardo Holmberg, Lin Calel (1910) y Olimpio Pitango de Monalia [1912-1915]. El tÃtulo de la Tesis, Permanencia y superación del '80 en dos escritores de 'entre-siglos', adelanta sus dos hipótesis centrales: la 'permanencia' o continuidad poética e ideológica del '80 en los trabajos de Loncán, y la 'superación' del mismo perÃodo por la práctica de escritura de Eduardo Holmberg. El cruce de ambos autores y sus respectivas obras pone de relieve un doble movimiento, el regreso al pasado por parte de quien desarrolló su carrera literaria durante los primeros cuarenta años del siglo XX [Loncán], y la evolución hacia el futuro de Holmberg que se desarrolló literariamente a lo largo del '80. Este doble movimiento 'el retroceso hacia las fuentes por parte de Loncán y el 'progreso' rupturista de Holmberg- mantiene una relación dialéctica con la historia social y polÃtica del paÃs en el primer caso, y una relación con la historia y con la filosofÃa de la historia en el segundo, sobre todo en Olimpio Pitango de Monalia, en la medida en que deconstruye la historiografÃa liberal oficial
Resumo:
The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI) in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars with stainless steel crowns and resin-filled celluloid forms. The main objectives of the selected treatment were to enhance the esthetics, restore masticatory function, and eliminate the teeth sensitivity. The child was monitored in the pediatric dentistry clinic at four-month intervals until the mixed dentition stage. Treatment not only restored function and esthetic, but also showed a positive psychological impact and thereby improved perceived quality of life. The preventive, psychological, and curative measures of a young child with AI were successful. This result can encourage the clinicians to seek a cost-effective technique such as stainless steel crowns, and resin-filled celluloid forms to reestablish the oral functions and improve the child's psychosocial development.
Resumo:
Stingless bees exhibit extraordinary variation in nest architecture within and among species. To test for phylogenetic association of behavioral traits for species of the Neotropical stingless bee genus Trigona s.s., a phylogenetic hypothesis was generated by combining sequence data of 24 taxa from one mitochondrial (16S rRNA) and four nuclear gene fragments (long-wavelength rhodopsin copy 1 (opsin), elongation factor-1 alpha copy F2, arginine kinase, and 28S rRNA). Fifteen characteristics of the nest architecture were coded and tested for phylogenetic association. Several characters have significant phylogenetic signal, including type of nesting substrate, nest construction material, and hemipterophily, the tending of hemipteroid insects in exchange for sugar excretions. Phylogenetic independent habits encountered in Trigona s.s. include coprophily and necrophagy.
Resumo:
Context. Fossil systems are defined to be X- ray bright galaxy groups ( or clusters) with a two- magnitude difference between their two brightest galaxies within half the projected virial radius, and represent an interesting extreme of the population of galaxy agglomerations. However, the physical conditions and processes leading to their formation are still poorly constrained. Aims. We compare the outskirts of fossil systems with that of normal groups to understand whether environmental conditions play a significant role in their formation. We study the groups of galaxies in both, numerical simulations and observations. Methods. We use a variety of statistical tools including the spatial cross- correlation function and the local density parameter Delta(5) to probe differences in the density and structure of the environments of "" normal"" and "" fossil"" systems in the Millennium simulation. Results. We find that the number density of galaxies surrounding fossil systems evolves from greater than that observed around normal systems at z = 0.69, to lower than the normal systems by z = 0. Both fossil and normal systems exhibit an increment in their otherwise radially declining local density measure (Delta(5)) at distances of order 2.5 r(vir) from the system centre. We show that this increment is more noticeable for fossil systems than normal systems and demonstrate that this difference is linked to the earlier formation epoch of fossil groups. Despite the importance of the assembly time, we show that the environment is different for fossil and non- fossil systems with similar masses and formation times along their evolution. We also confirm that the physical characteristics identified in the Millennium simulation can also be detected in SDSS observations. Conclusions. Our results confirm the commonly held belief that fossil systems assembled earlier than normal systems but also show that the surroundings of fossil groups could be responsible for the formation of their large magnitude gap.
The gene transformer-2 of Anastrepha fruit flies (Diptera, Tephritidae) and its evolution in insects
Resumo:
Background: In the tephritids Ceratitis, Bactrocera and Anastrepha, the gene transformer provides the memory device for sex determination via its auto-regulation; only in females is functional Tra protein produced. To date, the isolation and characterisation of the gene transformer-2 in the tephritids has only been undertaken in Ceratitis, and it has been shown that its function is required for the female-specific splicing of doublesex and transformer pre-mRNA. It therefore participates in transformer auto-regulatory function. In this work, the characterisation of this gene in eleven tephritid species belonging to the less extensively analysed genus Anastrepha was undertaken in order to throw light on the evolution of transformer-2. Results: The gene transformer-2 produces a protein of 249 amino acids in both sexes, which shows the features of the SR protein family. No significant partially spliced mRNA isoform specific to the male germ line was detected, unlike in Drosophila. It is transcribed in both sexes during development and in adult life, in both the soma and germ line. The injection of Anastrepha transformer-2 dsRNA into Anastrepha embryos caused a change in the splicing pattern of the endogenous transformer and doublesex pre-mRNA of XX females from the female to the male mode. Consequently, these XX females were transformed into pseudomales. The comparison of the eleven Anastrepha Transformer-2 proteins among themselves, and with the Transformer-2 proteins of other insects, suggests the existence of negative selection acting at the protein level to maintain Transformer-2 structural features. Conclusions: These results indicate that transformer-2 is required for sex determination in Anastrepha through its participation in the female-specific splicing of transformer and doublesex pre-mRNAs. It is therefore needed for the auto-regulation of the gene transformer. Thus, the transformer/transfomer-2 > doublesex elements at the bottom of the cascade, and their relationships, probably represent the ancestral state ( which still exists in the Tephritidae, Calliphoridae and Muscidae lineages) of the extant cascade found in the Drosophilidae lineage ( in which tra is just another component of the sex determination gene cascade regulated by Sex-lethal). In the phylogenetic lineage that gave rise to the drosophilids, evolution co-opted for Sex-lethal, modified it, and converted it into the key gene controlling sex determination.
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Background: The Trypanosoma cruzi genome was sequenced from a hybrid strain (CL Brener). However, high allelic variation and the repetitive nature of the genome have prevented the complete linear sequence of chromosomes being determined. Determining the full complement of chromosomes and establishing syntenic groups will be important in defining the structure of T. cruzi chromosomes. A large amount of information is now available for T. cruzi and Trypanosoma brucei, providing the opportunity to compare and describe the overall patterns of chromosomal evolution in these parasites. Methodology/Principal Findings: The genome sizes, repetitive DNA contents, and the numbers and sizes of chromosomes of nine strains of T. cruzi from four lineages (TcI, TcII, TcV and TcVI) were determined. The genome of the TcI group was statistically smaller than other lineages, with the exception of the TcI isolate Tc1161 (Jose-IMT). Satellite DNA content was correlated with genome size for all isolates, but this was not accompanied by simultaneous amplification of retrotransposons. Regardless of chromosomal polymorphism, large syntenic groups are conserved among T. cruzi lineages. Duplicated chromosome-sized regions were identified and could be retained as paralogous loci, increasing the dosage of several genes. By comparing T. cruzi and T. brucei chromosomes, homologous chromosomal regions in T. brucei were identified. Chromosomes Tb9 and Tb11 of T. brucei share regions of syntenic homology with three and six T. cruzi chromosomal bands, respectively. Conclusions: Despite genome size variation and karyotype polymorphism, T. cruzi lineages exhibit conservation of chromosome structure. Several syntenic groups are conserved among all isolates analyzed in this study. The syntenic regions are larger than expected if rearrangements occur randomly, suggesting that they are conserved owing to positive selection. Mapping of the syntenic regions on T. cruzi chromosomal bands provides evidence for the occurrence of fusion and split events involving T. brucei and T. cruzi chromosomes.
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The unusual bivalve Guiratingia mendesi is redescribed from the original material. Detailed analysis of hinge and muscle scars allows more refined designation of its taxonomic position and affinities to other Permian bivalves from the Parana Basin. Guiratingia mendesi is characterized by very small, anteriorly expanded shells, with a great number of muscle striae within the area delimited by the pallial line. A flattened area is noted alongside the commissure of shell. The presence of a triangular blunt tooth in the right valve allows its designation to Megadesmidae. The absence of accessory muscle scars ""a"" and ""b"" and pedal elevator indicate that the genus belongs to the Plesiocyprinellinae, a group of bivalves considered endemic to the Passa Dois Group. Guiratingia mendesi is found, however, in limestones of the Palermo Formation (Middle Artinskian), nearly 100 in below the base of the Irati Formation (Late Artinskian). Until now, it was believed that within the Permian succession of Parana Basin, pre-Irati bivalves were all gondwanic or cosmopolitan. Guiratingia mendesi was an endemic, active burrower that resembles Runnegariella fragilis from the Permian Teresina Formation. This indicates that during Palermo times restricted paleogeographic conditions have existed within the huge Parana epeiric sea, favoring endemicity, probably in marine bayments close to its margins. The presence of an anteriorly expanded shell in G mendesi is a condition also seen in other Mesozoic and Cenozoic anomalodesmatans, demonstrating the recurrence of shell forms in distinct lineages of this interesting group of bivalves.
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Advanced titanosaurian sauropods, such as nemegtosaurids and saltasaurids, were diverse and one of the most important groups of herbivores in the terrestrial biotas of the Late Cretaceous. However, little is known about their rise and diversification prior to the Late Cretaceous. Furthermore, the evolution of their highly-modified skull anatomy has been largely hindered by the scarcity of well-preserved cranial remains. A new sauropod dinosaur from the Early Cretaceous of Brazil represents the earliest advanced titanosaurian known to date, demonstrating that the initial diversification of advanced titanosaurians was well under way at least 30 million years before their known radiation in the latest Cretaceous. The new taxon also preserves the most complete skull among titanosaurians, further revealing that their low and elongated diplodocid-like skull morphology appeared much earlier than previously thought.
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The thick weathering profiles of humid tropical areas are an important, yet generally neglected, source of information on landscape evolution. Six complete profiles of the weathering mantle were sampled by drilling on the three stepped levels of the Campos do Jordao Plateau, on the NW flank of the Continental Rift of Southeastern Brazil. Mineralogical and micromorphological analyses of drill core samples, complemented by geochemical interpretations and by previous data on the upper saprolite, indicate continuity of a general lateritic trend during the entire process of mantle formation. Lateritization phases of different intensity were defined and considered to reflect adjustment to changes in environmental conditions created by the gradual uplift of the plateau to its present position. Older and more superficial materials related to intense lateritic weathering are characterized by allitization with direct formation of gibbsite from silicates, probably related to tropical climates existing immediately before the formation of the continental rift, during the Paleogene, and also before any significant increase in altitude. Monosialitization phase with general kaolinitization and restricted indirect formation of gibbsite from silicates could be associated to less aggressive climates that followed the Neogene (Miocene?) accentuation of uplift rates along the continental rift. The changes produced by uplift in the tropical climate eventually favored the development of a podzolization trend in soils above 1800m. (C) 2011 Elsevier BM. All rights reserved.
Resumo:
40Ar/39Ar laser incremental heating analyses of individual grains of supergene jarosite, alunite, and cryptomelane from weathering profiles in the Dugald River area, Queensland, Australia, show a strong positive correlation between a sample’s age and its elevation. We analyzed 125 grains extracted from 35 hand specimens collected from weathering profiles at 11 sites located at 3 distinct elevations. The highest elevation profile hosts the oldest supergene minerals, whereas progressively younger samples occur at lower positions in the landscape. The highest elevation sampling sites (three sites), located on top of an elongated mesa (255 to 275 m elevation), yield ages in the 16 to 12 Ma range. Samples from an intermediate elevation site (225 to 230 m elevation) yield ages in the 6 to 4 Ma range. Samples collected at the lowest elevation sites (200 to 220 m elevation) yield ages in the 2.2 to 0.8 Ma interval. Grains of supergene alunite, jarosite, and cryptomelane analyzed from individual single hand specimens yield reproducible results, confirming the suitability of these minerals to 40Ar/39Ar geochronology. Multiple samples collected from the same site also yield reproducible results, indicating that the ages measured are true precipitation ages for the samples analyzed. Different sites, up to 3 km apart, sampled from weathering profiles at the same elevation again yield reproducible results. The consistency of results confirms that 40Ar/39Ar geochronology of supergene jarosite, alunite, and cryptomelane yields ages of formation of weathering profiles, providing a reliable numerical basis for differentiating and correlating these profiles. The age versus elevation relationship obtained suggest that the stepped landscapes in the Dugald River area record a progressive downward migration of a relatively flat weathering front. The steps in the landscape result from differential erosion of previously weathered bedrock displaying different susceptibility to weathering and contrasting resistance to erosion. Combined, the age versus elevation relationships measured yield a weathering rate of 3.8 m. Myr−1 (for the past 15 Ma) if a descending subhorizontal weathering front is assumed. The results also permit the calculation of the erosion rate of the more easily weathered and eroded lithologies, assuming an initially flat landscape as proposed in models of episodic landscape development. The average erosion rate for the past 15 Ma is 3.3 m. Myr−1, consistent with erosion rates obtained by cosmogenic isotope studies in the region.
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Hemichordates were traditionally allied to the chordates, but recent molecular analyses have suggested that hemichordates are a sister group to the echinoderms, a relationship that has important consequences for the interpretation of the evolution of deuterostome body plans. However, the molecular phylogenetic analyses to date have not provided robust support for the hemichordate + echinoderm clade. We use a maximum likelihood framework, including the parametric bootstrap, to reanalyze DNA data from complete mitochondrial genomes and nuclear 18S rRNA. This approach provides the first statistically significant support for the hemichordate + echinoderm clade from molecular data. This grouping implies that the ancestral deuterostome had features that included an adult with a pharynx and a dorsal nerve cord and an indirectly developing dipleurula-like larva.