5 resultados para Long digital extensor tendon

em DRUM (Digital Repository at the University of Maryland)


Relevância:

30.00% 30.00%

Publicador:

Resumo:

Long-song (Urtyn duu) is a prominent Mongolian traditional folk song genre that survived throughout the socialist period (1921-1990) and throughout the political transformation of Mongolia from socialism to democratic capitalism after the Soviet Union was dismantled and terminated its aid to Mongolia in 1990. This dissertation, based on research conducted from 2006 to 2010, presents and investigates the traces of singers' stories and memories of their lives, songs, and singing, through the lens of the discourse on change and continuity in, and as, folk tradition. During the socialist period, this genre was first considered backward, and was then subtly transformed into an urban national style, with the formation of a boundary between professionalism and amateurism among long-song singers and with selective performance of certain songs and styles. This boundary was associated with politics and ideology and might be thought to have ended when the society entered its post-socialist period. However, the long-song genre continued to play a political role, with different kinds of political meaning one the one hand and only slight musical modification on the other. It was now used to present a more nostalgic and authentic new Mongolian identity in the post-socialist free market. Through my investigation, I argue that the historical transition of Mongolia encompassed not merely political or economic shifts, but also a deeper transformation that resulted in new cultural forms. Long-song provides a good case study of the complicated process of this cultural change.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Understanding how biodiversity spatially distribute over both the short term and long term, and what factors are affecting the distribution, are critical for modeling the spatial pattern of biodiversity as well as for promoting effective conservation planning and practices. This dissertation aims to examine factors that influence short-term and long-term avian distribution from the geographical sciences perspective. The research develops landscape level habitat metrics to characterize forest height heterogeneity and examines their efficacies in modelling avian richness at the continental scale. Two types of novel vegetation-height-structured habitat metrics are created based on second order texture algorithms and the concepts of patch-based habitat metrics. I correlate the height-structured metrics with the richness of different forest guilds, and also examine their efficacies in multivariate richness models. The results suggest that height heterogeneity, beyond canopy height alone, supplements habitat characterization and richness models of two forest bird guilds. The metrics and models derived in this study demonstrate practical examples of utilizing three-dimensional vegetation data for improved characterization of spatial patterns in species richness. The second and the third projects focus on analyzing centroids of avian distributions, and testing hypotheses regarding the direction and speed of these shifts. I first showcase the usefulness of centroids analysis for characterizing the distribution changes of a few case study species. Applying the centroid method on 57 permanent resident bird species, I show that multi-directional distribution shifts occurred in large number of studied species. I also demonstrate, plain birds are not shifting their distribution faster than mountain birds, contrary to the prediction based on climate change velocity hypothesis. By modelling the abundance change rate at regional level, I show that extreme climate events and precipitation measures associate closely with some of the long-term distribution shifts. This dissertation improves our understanding on bird habitat characterization for species richness modelling, and expands our knowledge on how avian populations shifted their ranges in North America responding to changing environments in the past four decades. The results provide an important scientific foundation for more accurate predictive species distribution modeling in future.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Frustrated systems, typically characterized by competing interactions that cannot all be simultaneously satisfied, are ubiquitous in nature and display many rich phenomena and novel physics. Artificial spin ices (ASIs), arrays of lithographically patterned Ising-like single-domain magnetic nanostructures, are highly tunable systems that have proven to be a novel method for studying the effects of frustration and associated properties. The strength and nature of the frustrated interactions between individual magnets are readily tuned by design and the exact microstate of the system can be determined by a variety of characterization techniques. Recently, thermal activation of ASI systems has been demonstrated, introducing the spontaneous reversal of individual magnets and allowing for new explorations of novel phase transitions and phenomena using these systems. In this work, we introduce a new, robust material with favorable magnetic properties for studying thermally active ASI and use it to investigate a variety of ASI geometries. We reproduce previously reported perfect ground-state ordering in the square geometry and present studies of the kagome lattice showing the highest yet degree of ordering observed in this fully frustrated system. We consider theoretical predictions of long-range order in ASI and use both our experimental studies and kinetic Monte Carlo simulations to evaluate these predictions. Next, we introduce controlled topological defects into our square ASI samples and observe a new, extended frustration effect of the system. When we introduce a dislocation into the lattice, we still see large domains of ground-state order, but, in every sample, a domain wall containing higher energy spin arrangements originates from the dislocation, resolving a discontinuity in the ground-state order parameter. Locally, the magnets are unfrustrated, but frustration of the lattice persists due to its topology. We demonstrate the first direct imaging of spin configurations resulting from topological frustration in any system and make predictions on how dislocations could affect properties in numerous materials systems.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Psychological research has strongly documented the memory-enhancing effects of emotional arousal, while the effects of acute aerobic exercise on memory are not well understood. Manipulation of arousal has been shown to enhance long-term memory for emotional stimuli in a time-dependent fashion. This presents an opportunity to investigate the role of acute exercise in memory modulation. The purpose of this study was to determine the time-dependent relationship between acute exercise-induced arousal and long-term emotional memory. Participants viewed pleasant, neutral, and unpleasant images before or after completing a high-intensity session of cycling exercise. Salivary alpha-amylase, a biomarker of central norepinephrine, was measured as an indicator of arousal. No effects of exercise on recognition memory were revealed, however; a single session of high-intensity cycling increased salivary alpha-amylase. Our results also indicate that the influence of exercise on emotional responsiveness should be considered in further exploration of the memory-enhancing potential of acute exercise.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Uncle Dave Macon provided an essential link between nineteenth-century, urban popular stage music (especially the minstrel show and vaudeville) and commercialized country music of the 1920s. He preserved through his recordings a large body of songs and banjo techniques that had their origins in urban-based, nineteenth-century vaudeville and minstrelsy. Like the minstrel and vaudeville performers of the nineteenth century, Macon told jokes and stories, employed attention-grabbing stage gimmicks, marketed himself with boastful or outrageous slogans, and dressed with individual flair. At the same time, Macon incorporated many features from the rural-based folk music of Middle Tennessee. Overall, Macon’s repertoire, musical style, and stage persona (which included elements of the rube, country gentleman, and old man) demonstrated his deep absorption, and subsequent reinterpretation, of nineteenth-century musical traditions. Macon’s career offers a case study in how nineteenth-century performance styles, repertoire, and stage practices became a part of country music in the 1920s. As an artist steeped in two separate, but overlapping, types of nineteenth-century music—stage and folk—Macon was well-positioned to influence the development of the new commercial genre. He brought together several strains of nineteenth-century music to form a modern, twentieth-century musical product ideally suited to the new mass media of records, radio, and film. By tracing Macon’s career and studying his music, we can observe how the cross-currents of rural and popular entertainment during the nineteenth and early twentieth centuries interacted to form the commercial genre we now know as country music.