5,359 research outputs found

    Sandhill Crane Roost Selection, Human Disturbance, and Forage Resources

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    Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over 5 spring migration seasons (2003–2007) to quantify resource selection functions of roost sites on the central Platte River using a discrete choice analysis. Sandhill cranes generally showed stronger selection for wider channels with shorter bank vegetation situated farther from potential human disturbance features such as roads, bridges, and dwellings.Furthermore, selection for roost sites with preferable physical characteristics (wide channels with short bank vegetation) was more resilient to nearby disturbance features than more narrow channels with taller bank vegetation. The amount of cornfields surrounding sandhill crane roost sites positively influenced relative probability of use but only for more narrow channels \u3c100m and those with shorter bank vegetation. We confirmed key resource features that sandhill cranes selected at river channels along the Platte River, and after incorporating spatial variation due to human disturbance, our understanding of roost site selection was more robust, providing insights on how disturbance may interact with physical habitat features. Managers can use information on roost-site selection when developing plans to increase probability of crane use at existing roost sites and to identify new areas for potential use if existing sites become limited

    What has made deer farming in New Zealand so successful? The importance of venison quality, understanding the industry, the market and the biology of the animals

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    In summarising these aspects of success within the NZ deer industry we can note: (1) NZ traditional farming skills of pasture based production have been readily adapted to deer farming. (2) The industry has grown with strength through the diversity of its participants, leading farmers, innovative researchers, business investors and leaders and the NZDFA and its membership. All are united in their determination that market signals, rather than farm production demands should shape the development of venison supply and presentation. (3) The frank and rapid exchange of research results, farmer innovation, market information and exchange of experience and ideas within the industry. (4) The overwhelming commitment to quality production. Biologically, deer has their own contributing attributes: (a) they are intelligent and easy to farm; (b) they are efficient converters of pasture and supplements to venison or to progeny; (c) they thrive throughout NZ varied agricultural terrain on native grasses or improved pasture, and have a healthy and long productive life; (d) they have enormous climatic and environmental tolerance, a defined breeding season and predictable calving pattern; (e) they are immensely seasonal, and now, when feeding and breeding requirements are well understood in terms of that seasonality, productive growth targets are readily set and achieved to accommodate the market signal; (f) they are simple to manage with a minimum of labour and physical inputs

    Isopoda collected by the Bryant Walker Expedition to British Guiana, with notes on Crustacea from other localities

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    http://deepblue.lib.umich.edu/bitstream/2027.42/56485/1/OP046.pd

    But Where Will They Build Their Nest? Liberalism and Communitarian Resistance in American Cinematic Portrayals of Jewish-Gentile Romances

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    This dissertation analyzes approximately fifty American films that feature predominantly heterosexual interfaith/intercultural romantic, sexual or marital relations between Jewish and Gentile protagonists. It asks what political or social ideals can be illustrated by these portrayals, and how these films can be taken cumulatively to explore trends in modern life. The author places liberalism at the heart of the mainstream Hollywood discourse on intermarriage, and shows how films that run counter to the expectations of liberal romances may reflect communitarian critiques of liberal tenets. The issue of intermarriage is contextualized with a discussion of the endogamous tradition in Judaism, and by an exploration of American liberalism. Tools used to read the films include genre theory, representational discourses and Thomas Wartenberg’s narrative theory of the unlikely couple in film (1999) as a mode of social critique. Main political philosophy theorists engaged include Michael Walzer and Charles Taylor. Some of the key films explored are Keeping the Faith (2000), the 1927 and 1980 versions of The Jazz Singer, and Crossing Delancey (1988). This dissertation does not argue that these films are made with explicitly liberal or communitarian goals, but that they are evocative of the efforts of Americans to contend with modern issues. While close reading of the films themselves was the main goal and method of the work, the author makes suggestions for ways in which future work can examine the impact of these films on the Jewish community, especially in terms of gender relations. Drawing on scholarship of the Jewish image in film, this work builds on previous knowledge in the fields of Jewish cultural studies and film studies by giving extensive attention to the intimate relations between Jews and Gentiles. By addressing not only the Hollywood “happy ending” but also the negative outcomes, this work advances new ways of seeing resistance to universalizing tendencies in romance and a critique of the historically dominant liberal ideology in American film

    Photometry and polarimetry of the moon and their relationship to physical properties of the lunar surface

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    Photometry and polarimetry of moon and relation to physical properties of lunar surfac

    Development of Anti-VEGF Therapies for Intraocular Use: A Guide for Clinicians

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    Angiogenesis is the process by which new blood vessels form from existing vessel networks. In the past three decades, significant progress has been made in our understanding of angiogenesis; progress driven in large part by the increasing realization that blood vessel growth can promote or facilitate disease. By the early 1990s, it had become clear that the recently discovered “vascular endothelial growth factor” (VEGF) was a powerful mediator of angiogenesis. As a result, several groups targeted this molecule as a potential mediator of retinal ischemia-induced neovascularization in disorders such as diabetic retinopathy and retinal vein occlusion. Around this time, it also became clear that increased intraocular VEGF production was not limited to ischemic retinal diseases but was also a feature of choroidal vascular diseases such as neovascular age-related macular degeneration (AMD). Thus, a new therapeutic era emerged, utilizing VEGF blockade for the management of chorioretinal diseases characterized by vascular hyperpermeability and/or neovascularization. In this review, we provide a guide for clinicians on the development of anti-VEGF therapies for intraocular use
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