145 research outputs found

    Canine Rabies Ecology in Southern Africa

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    Understanding the persistence of rabies in multiple canine hosts in southern Africa requires applying the principles of metapopulation biology

    Extreme Ultraviolet Reflective Grating Characterization and Simulationsfor the Aspera SmallSat Mission

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    The Aspera SmallSat mission is designed to detect and map the warm-hot gaseous component of the halos of nearby galaxies through long-slit spectroscopy of the ionized O VI emission line (103.2 nm) for the first time. The Aspera Rowland circle type spectrograph uses a toroidal grating coated with a multilayer film consisting of aluminum, lithium fluoride, and magnesium fluoride capping to optimize reflectivity in the extreme ultraviolet (EUV) waveband from 103 to 104nm. We discuss the grating characterization test setup at the University of Arizona (UA), which will validate the multilayer coating and grating efficiency in a UV vacuum chamber. We also simulate the reflectivity of the multilayer thin film coating using IMD IDL software to compare simulated results with measured reflectivity. Additionally, non-sequential ray trace simulations and 3D CAD modeling are used for verification of the test setup. Finally, the implications of the differences between the measured and simulated reflectivity and grating efficiencies are considered, including impact to the mission

    The composing processes of three Southeast Asian writers at the post-secondary level: An exploratory study

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    The purpose of this study was to explore the writing processes of Southeast Asian students with different educational backgrounds. The secondary pur-pose was to determine if the methodology used was valid and reliable. Stu-dents were given an article to read and then asked to write their opinion about the topic. Students were videotaped as they wrote, with the camera focused specifically on the movement of their pen on paper. They were then interviewed about their writing process and about what they had been think-ing during selected pause times, which had been captured on videotape and were played back to stimulate recall of the students ’ thought processes. Their responses were transcribed and then categorized according to what aspect of their writing they had been attending to during their pauses as well as what strategies they used to help generate a solution to a perceived problem in their writing (Cumming, 1989). The students differed in their degree of metacognitive awareness, their ability to integrate information from the read-ing into their writing, the amount of attention paid to different aspects o
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