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Beyond Generalist vs. Specialist: Making Connections between Genre Theory and Writing Center Pedagogy
Following the trend in composition scholarship of the 1980s and 90s toward theorizing about genre as a social and rhetorical construct, several colleges and universities across the nation have worked to implement genre-based curricula in their writing courses. From first-year writing classes to writing across the curriculum programs, instructors have steadily recognized the benefits of genre pedagogies and asked their student writers to compose in a variety of genres. However, while genre theory has found a home in several college classrooms, very little attention has been paid to the potential application of genre theory to writing center pedagogy.University Writing Cente
Calcareous Nannoplankton Assemblages across the Pliocene-Pleistocene Transition in the Southwestern Indian Ocean, IODP Site U1475
International Ocean Discovery Program (IODP) Expedition 361 cored six sites along the greater Agulhas Current system. An objective of this expedition was to determine the dynamics of the Indian-Atlantic Ocean Gateway circulation during Pliocene-Pleistocene climate changes in association with changing wind fields and migrating ocean fronts. The Indian-Atlantic Ocean Gateway contains a pronounced oceanic frontal system, the position of which has the potential to influence global climate on millennial scales. Owing to the physical differences between the frontal zones, this region has complex biogeochemistry, changes in phytoplankton distribution, and variations in primary productivity. Site U1475 was cored on the Agulhas Plateau in the Southwestern Indian Ocean and recovered a complete sequence of calcareous ooze spanning the last ~7 Ma. The calcareous nannoplankton assemblage shows an increase of taxa associated with cooler water across the Pliocene-Pleistocene Transition (PPT) interval suggesting that a long- term change in sea surface temperature and nutrient availability took place across the PPT, potentially linked to the northward migration of the Subtropical Front
Globally Convergent Parallel Algorithm for Zeros of Polynomial Systems
Certain classes of nonlinear systems of equations, such as polynomial systems, have properties that make them particularly amenable to solution on distributed computing systems. Some algorithms, considered unfavorably on a single processor serial computer, may be excellent on a distributed system. This paper considers the solution of polynomial systems of equations via a globally convergent homotopy algorithm on a hypercube. Some computational results are reported
The application of portable air cleaners in spaces occupied by vulnerable people during wildfire events
In this study, PM2.5 concentrations were collected and documented during wildfire smoke impacted days using PurpleAir PA-II sensors at three different locations in a community located in the northwestern United States. Each location was comprised of three co-located sensors with one sensor positioned outdoors, one sensor indoors, and one sensor indoors with an air cleaner in the room. The relationship between both indoor and outdoor PM2.5 concentrations provided evidence on the effectiveness of sheltering indoors from wildfire smoke events with and without an air purification system
Calcareous Nannoplankton Assemblages across the Pliocene-Pleistocene Transition in the Southwestern Indian Ocean, IODP Site U1475
International Ocean Discovery Program (IODP) Expedition 361 cored six sites along the greater Agulhas Current system. An objective of this expedition was to determine the dynamics of the Indian-Atlantic Ocean Gateway circulation during Pliocene-Pleistocene climate changes in association with changing wind fields and migrating ocean fronts. The Indian-Atlantic Ocean Gateway contains a pronounced oceanic frontal system, the position of which has the potential to influence global climate on millennial scales. Owing to the physical differences between the frontal zones, this region has complex biogeochemistry, changes in phytoplankton distribution, and variations in primary productivity. Site U1475 was cored on the Agulhas Plateau in the Southwestern Indian Ocean and recovered a complete sequence of calcareous ooze spanning the last ~7 Ma. The calcareous nannoplankton assemblage shows an increase of taxa associated with cooler water across the Pliocene-Pleistocene Transition (PPT) interval suggesting that a long- term change in sea surface temperature and nutrient availability took place across the PPT, potentially linked to the northward migration of the Subtropical Front
Upgrades to the International Space Station Urine Processor Assembly
The ISS Urine Processor Assembly (UPA) began operations in November 2008. Though the UPA has successfully generated distillate from crew urine, several modifications and upgrades have been implemented to improve overall system performance throughout the years. Current and future upgrades to the UPA will continue to focus on improved system performance and reliability, focusing primarily on the Distillation Assembly and upgrades to the UPA vacuum pump. Work towards a flight demonstration experiment of a vacuum pump utilizing scroll pump technologies has also continued forward. The following paper discusses progress on these various concepts, including the implementation of a more reliable drive belt, improved methods for managing condensate in the stationary bowl of the Distillation Assembly, installation of improved centrifuge bearings, implementation of a liquid level sensor, and upgrades to the UPA vacuum pump
Comparison of microanalytical methods for estimating H20 contents of silicic volcanic glasses
Three methods of estimating H20 contents of geologic glasses are compared: (1) ion
microprobe analysis (secondary ion mass spectrometry), (2) Fourier-transform infrared
spectroscopy (FTIR), and (3) electron microprobe analysis using the Na decay-curve method.
Each analytical method has its own advantages under certain conditions, depending
on the relative importance of analytical accuracy, precision, sensitivity, spatial resolution,and convenience, and each is capable of providing reasonably accurate estimates of the H20, or total volatile, content of geologic glasses. The accuracy of ion microprobe analyses
depends critically on the availability of well-characterized hydrous standard glasses. Precision is often better than 0,2 wt% (10). The method provides good spatial resolution (-15
#m) and the capability to determine simultaneously the abundance of other volatile species of interest (e.g., F, B). FTIR spectroscopy provides excellent analytical sensitivity (-10
ppm), accuracy and precision «0.1 wt%), and the capability to determine the abundance
of H20 and C02 species (H20, OH-, C02' eOj-) in analyzed glasses, although the spatial
resolution (> 25-35 #m) is not as good as that of the ion microprobe. The main advantages
of the estimation of H20 contents of hydrous glasses using the electron microprobe are
excellent spatial resolution (- 10 #m) and analytical convenience. The disadvantages are
that accuracy and precision (>0.5 wt%) are not as good as those associated with the other
methods, but, for certain applications, these uncertainties may be acceptable for the estimation of H20 contents of H20-rich (> 1 wt%) samples
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