University of Kentucky

About: University of Kentucky is a education organization based out in Lexington, Kentucky, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 43933 authors who have published 92195 publications receiving 3256087 citations. The organization is also known as: UK.

Density and extra-pair fertilizations in birds: a comparative analysis

Abstract: Moller and Birkhead (1992, 1993) reported that extra-pair copulations (EPCs) occur more frequently in colonial than dispersed nesting birds. We comprehensively reviewed published data to investigate how breeding density affects extra-pair fertilizations (EPFs). Within species EPFs appeared to increase with density: two of three studies on colonial breeders and six of eight on dispersed nesters showed increases in EPFs with increasing density. However, comparisons among species (n = 72) revealed no evidence that EPF frequencies correlated with (1) nesting dispersion, (2) local breeding density, or (3) breeding synchrony, even when each of these variables in turn was held constant and phylogenetic relationships were taken into account via contrast analyses. Methodological and biological reasons for the disparity between observational studies of EPCs and molecular genetic analyses of EPFs are discussed.

Real-Time Visibility-Based Fusion of Depth Maps

Abstract: We present a viewpoint-based approach for the quick fusion of multiple stereo depth maps. Our method selects depth estimates for each pixel that minimize violations of visibility constraints and thus remove errors and inconsistencies from the depth maps to produce a consistent surface. We advocate a two-stage process in which the first stage generates potentially noisy, overlapping depth maps from a set of calibrated images and the second stage fuses these depth maps to obtain an integrated surface with higher accuracy, suppressed noise, and reduced redundancy. We show that by dividing the processing into two stages we are able to achieve a very high throughput because we are able to use a computationally cheap stereo algorithm and because this architecture is amenable to hardware-accelerated (GPU) implementations. A rigorous formulation based on the notion of stability of a depth estimate is presented first. It aims to determine the validity of a depth estimate by rendering multiple depth maps into the reference view as well as rendering the reference depth map into the other views in order to detect occlusions and free- space violations. We also present an approximate alternative formulation that selects and validates only one hypothesis based on confidence. Both formulations enable us to perform video-based reconstruction at up to 25 frames per second. We show results on the multi-view stereo evaluation benchmark datasets and several outdoors video sequences. Extensive quantitative analysis is performed using an accurately surveyed model of a real building as ground truth.

A Primer on Practices

Abstract: As the title indicates, this chapter is a primer on practices. It begins by discussing practice theory generally but mostly presents my own ideas. The topics addressed are practices, activities, and social phenomena, with special attention to temporality and the unfolding of practices. The chapter concludes with comments about conducting research on practices. My goal is to provide practice theoretical stimulation to readers interested in practice-based education and research.

Höhere Acene: vielseitige organische Halbleiter

Abstract: Acene werden wegen ihrer einzigartigen elektronischen Eigenschaften, die auf der Topologie ihrer π-Systeme beruhen, seit langem untersucht. Berichte uber die bemerkenswerten Halbleitereigenschaften hoherer Homologe haben in letzter Zeit zu verstarkten Forschungsaktivitaten gefuhrt. Es wurden neue Verfahren zur Synthese, Funktionalisierung und Reinigung sowie zur Herstellung organoelektronischer Bauteile entwickelt. Durch Untersuchungen an hochreinen Acen-Einkristallen wurden die charakteristischen elektronischen Eigenschaften und Kenngrosen fur die Beurteilung von Dunnschichtbauteilen ermittelt. Um die Verarbeitbarkeit in Losung zu verbessern, wurden neuartige Funktionalisierungsmethoden entwickelt. Die fur elektronische Anwendungen erwunschten Eigenschaften nichtfunktionalisierter Acene bleiben bei der Funktionalisierung erhalten. Mit diesen Verfahren wurden kurzlich Derivate hoherer Acene als Pentacen, die zuvor kaum zuganglich waren, erhalten, sodass Struktur-Eigenschafts-Beziehungen untersucht werden konnten.