Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 20 for “"barn owl"”.
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Conserving a charismatic grassland species in Illinois: the barn owl
… habitat have declined. One such species is the barn owl, Tyto alba, which is threatened or endangered in 5 states. The conversion of grasslands into agricultural or developed areas has cost barn owls both suitable foraging habitat and nest sites. To mitigate this loss and support barn owl …
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Representation of binaural masking level difference in the inferior colliculus of the barn owl (tyto alba)
… important for animals and humans and crucial for barn owls. In natural environments, the spatial separation of signal and interfering noise improves detectability of the signal. In psychoacoustics experiments this is achieved by changing the spatial attributes of the sound, for example by shifting …
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Processing of auditory signals in the forebrain of the Barn Owl : neural mechanisms of across-frequency integration
… manner to the ITD of the signal. In the barn owl’s external nucleus of the inferior colliculus (ICX), a part of the tectofugal pathway, phase ambiguities are resolved by integrating ITD information across frequency channels. This thesis focusses on ITD processing in the parallel …
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Fundamentals of spatial vision in the barn owl (Tyto alba pratincola) : ocular aberrations, grating acuity, contrast sensitivity, and vernier acuity
Optical quality in barn owl eyes was measured with a standard Tscherning-type wavefront aberrometer. The results revealed that barn owl eyes have excellent optical quality. Higher-order aberrations were about 3-fold lower than has been reported in human eyes with similar methods and under …
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Behavioral responses to frequency specific head related transfer functions as filtered by the facial ruff in the Barn owl (Tyto alba)
The barn owl is, due to its numerous morphological and neuronal adaptations to sound localization, a long-established model animal for the auditory system. Besides extensive research on the topic within the last decades, it is still unclear how direction- and frequency-dependent physical cues …
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Development of Auditory Sensitivity in Barn Owls (Tyto furcata pratincola)
The development of hearing in the juvenile barn owl was investigated using tones (500 Hz to 12 kHz) and clicks of different rates (5-90 Hz). Auditory evoked potentials (AEPs) of the auditory nerve were recorded using the auditory brainstem response (ABR). Barn owl hearing matured in a similar trend …
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A taphonomic investigation of the agency of microfaunal accumulation at Elands Bay Cave
… the accumulation of these assemblages was the Barn owl. These micromammal assemblages were used to make extrapolations of past changes in vegetation and climate. It was assumed that the agent of accumulation, the Barn owl, remained constant. This thesis used taphonomy to analyse the micromammal …
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Charakterisierung von Acyl-CoA-Reduktasen
… were cloned from the uropygial glands of barn owl (Tyto alba), domestic chicken (Gallus gallus domesticus) and domestic goose (Anser anser domesticus). Heterologous expression studies in Saccharomyces cerevisiae showed that they encode membrane associated enzymes which catalyze a NADPH …
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Aspects of sound localization and spatial attention in barn owls and rats
… auditory spatial attention: first, the barn owl as a highly-developed auditory specialist and, secondly, the rat as an auditory generalist. An influence of spatial attention on sound localization has solely been demonstrated in humans so far. Since barn owls are important animal models …
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Anatomical, morphometrical and biomechanical studies of barn owls' and pigeons' wings
Wings and feathers of barn owls (Tyto alba) were investigated with anatomical, morphometrical and biomechanical methods in order to specify noise reduction and noise suppressing structures evolved by the owl. Pigeons (Columba livia) with a similar body weight were taken as a reference species. Barn …
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The taphonomy of a micromammalian faunal assemblage from the Saldanha Bay Yacht Club : a contribution to the study of the South African west coast palaeoenvironments
… of the inferred accumulator of the fauna, the barn owl, although the spotted eagle owl has not been completely ruled out. The study of the SBYC micromammalian fauna has underscored the need to integrate both taphonomic and ecological factors in the attempts to infer potential predators that …
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Factors that affect owl ecology in an agricultural matrix in east Gauteng
… also contains the vulnerable African grass-owl (Tyto capensis), and three other owl species namely, the western barn owl (Tyto alba), the spotted eagle-owl (Bubo africanus) and the marsh owl (Asio capensis). The extensive road network, and particularly the N17 highway in this area have …
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On the perceptual identity of depth vision in the owl
… new information about visual perception in the owl. First, a behaviour shaping technique was developed that prepared owls to be visually tested by images presented on a distant CRT-monitor. Second, it was demonstrated that owls can abstract the figure-ground organisation of computer generated …
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Auditory brainstem neurons as components of a biohybrid system
… characterise their properties in vitro. This knowledge provides the basis for later attempts to reconstruct the NM/NL circuit as a biohybrid system. Neurons from NM and NL were excised at an early stage of development (E6.5) and cultivated for up to 15 days in vitro. The cells in the culture …
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Biologically inspired binaural sound source localization and tracking for mobile robots
… modulating a robot's attention inspired from the barn owl and last, a tracking system which makes it possible for a robot to track objects emitting sounds. Regarding sound source localization, the method that was best understood and evaluated is a method based on the evaluation of interaural time …
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Epidemiología molecular en Escherichia coli procedente de fauna salvaje: resistencia antimicrobiana, virulencia y diversidad y diversidad genética
… a qnrS1 gene was identified in an E. coli from a barn owl. All the ESBL and plasmid-mediated AmpC encoding genes were transferable by conjugation, and we observed some associations like blaCTX-M-1/IncN, blaSHV-12/IncI1 or blaCMY-2/IncI1. Although some ESBL/AmpC-producing E. coli lineages were …