798 research outputs found

    The Effect of Urbanization on Bumble Bee Communities in Greater Philadelphia

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    Bumble bees (Bombus spp.) are among the most important wild pollinators in temperate ecosystems in North America and Europe, and are believed to be vital to the functioning of the pollination networks in which they occur. Accordingly, evidence of their overall decline in Europe and more selective decline in the U.S. has raised concern about the long term persistence of many species. Human-induced changes in land use, including the loss of natural and semi-natural habitat and associated floral resources, are purported causes in several cases. Declines prompted an investigation of this potential trend in the urbanized landscape in and surrounding Philadelphia, PA. We surveyed the species richness and abundance of bumble bee communities in ten half-ha plots located in restored, managed meadows along a gradient of urban and suburban development in the Philadelphia metropolitan area from June 1 to August 15, 2006. In conjunction with collections, we measured floral density within each plot. We calculated the proportion of developed land at differing spatial scales ranging from 500 to 4000 m from survey sites. General linear models were used to test the effect of developed land, local meadow size, and floral resource density on overall bumble bee species richness and abundance. 
Development did not have any detectable effect on species richness at any tested spatial scale. Bee abundance was best explained by a model that included the proportion of developed land at the 2500 m scale. In contrast to our expectations, total bumble bee abundance was significantly higher in plots with a higher proportion of developed land surrounding the site (F1,5 = 8.13, P = 0.04). Local floral density did not significantly affect richness or abundance (F 1,5 = 0.93, P = 0.34), nor was local resource quality associated with development (r = 0.52, P = 0.12) . We hypothesize that gardens maintained in urban and suburban landscapes may provide an important and consistent food supply to bumble bees throughout the duration of their colony cycle. Forested habitats, which were the other dominate habitat type, may actually be relatively poor in bumble bee resources following closure of the canopy in late spring. This research indicates that restored meadows are excellent habitat for bumble bees and may promote pollination services in urbanized settings.
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    Description of the Spacecraft Control Laboratory Experiment (SCOLE) facility

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    A laboratory facility for the study of control laws for large flexible spacecraft is described. The facility fulfills the requirements of the Spacecraft Control Laboratory Experiment (SCOLE) design challenge for a laboratory experiment, which will allow slew maneuvers and pointing operations. The structural apparatus is described in detail sufficient for modelling purposes. The sensor and actuator types and characteristics are described so that identification and control algorithms may be designed. The control implementation computer and real-time subroutines are also described

    Data quality in European primary care research databases. Report of a workshop held in London September 2013

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    Primary care research databases provide a significant resource for health services and epidemiological research. However since data are recorded primarily for clinical care their suitability for research may vary widely according to the research application or recording practices of individual general practitioners. A methodological approach for characterising data quality is required. We describe a one-day workshop entitled “Towards a common protocol for measuring and monitoring data quality in European primary care research databases”. Researchers, database experts and clinicians were invited to give their perspectives on data quality and to exchange ideas on what data quality metrics should be made available to researchers. We report the main outcomes of this workshop, including a summary of the presentations and discussions and suggested way forward

    Web 2.0 Sprint Session: 4 Rapid Fire Presentations

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    Nate Bunnyfield - Posterous is a leading blogging platform with some fantastic social media integration. We will explore basic lifestreaming (posting a video to Twitter/Facebook from a mobile phone), collaborative blogging, and advanced (setting up DNS entries; using Google Analytics; and customizing themes) use cases. Rosemary Talab - Learn how to use Twitter, Tweetdeck, Tweetworks, Broadtexter and cell phones with videconference classes to enhance teaching options, student collaboration and networking. See a live demonstration of these features with students. Hattie Williams - No one has the time, resources, or energy to adopt the latest and greatest development tool every three months or however often they appear. So how can you stay ahead of the curve with what you have? I propose that all you need (at absolute minimum) is expertise on three concepts: Hotspots,Graphics Editing,and On-Screen Presentation. In addition, it always helps to have full command of the product you are using. Print off those help manuals. Leave them at your work station or do not hesitate to hit the button and look things up. You may be surprised to learn how robust your tool actually is; that however is a discussion I will leave for a different session. In this presentation, I will demonstrate how to use these three concepts and some basic functions to create engaging training with Camtasia, beyond basic movie making. The tips in this presentation can be generalized to PowerPoint, HTML, basic Flash, or any other tool that allows you to use images + buttons. Jenell Williams - Basics of Voice Thread

    Why We Oppose Gold Open Access

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    A pragmatic approach for measuring data quality in primary care databases

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    There is currently no widely recognised methodology for undertaking data quality assessment in electronic health records used for research. In an attempt to address this, we have developed a protocol for measuring and monitoring data quality in primary care research databases, whereby practice-based data quality measures are tailored to the intended use of the data. Our approach was informed by an in-depth investigation of aspects of data quality in the Clinical Practice Research Datalink Gold database and presentations of the results to data users. Although based on a primary care database, much of our proposed approach would be equally applicable to other health care databases

    Academic Leadership: Creating Successful (New) Leaders & Preserving Institutional Memory

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    Participants will consider the following topics: identifying & articulating the primary responsibilities of a leadership position; preserving important institutional mores and memories during a change in leadership; developing institutional structures and materials to support new leaders in such transitions. Participants will leave with an action plan/checklist for supporting new leaders

    Using the Automated OCLC/WLN Conspectus at a Small University

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    Well Log Segmentation in Spectral Domain

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    Classic well log interpretation involves direct horizon mapping using log signature, attributes cross plot, etc to produce lithologic section for the delineation, exploration and production of hydrocarbon in oil and gas fields. The methods operate on recorded lithologic logs without adequate calibration. These result in interpretational ambiguities because of relatively poor resolution of well log owing to its recording in time, under sampling and coarse processing. In this paper, a new technique and algorithm for segmenting well log using discrete Fourier transform in the interpretation of well data obtained from the Niger Delta is presented. The aims and objectives of the study are to segment well logs into their constituent lithology in time domain, transform the well data from time to frequency domain and segment, and deduce viable diagnostic attributes such as magnitude, phase and frequency from the transform coefficients which could be used to identify the most probable zonation/contact in the well. The algorithm adopts Short time Fourier transform technique in the time to frequency transformation and is implementable on both standard and general seismic and well log interpretational platforms. It directly computes the spectral equivalent of the adopted lithologic log (Gamma-ray) and recovers hitherto lost frequency information. The results of the spectral decomposition of the well data yielded frequency (pseudo) logs that reveal subtle sub-well horizons and differences in lithology. By revealing masked horizons and better delineating and delimiting reservoirs, more hydrocarbons will be recovered and field development will be enhanced. Keywords: Fourier transform, Spectral decompositio
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