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More Than Assessment: What ePortfolios Make Possible for Students, Faculty, and Curricula
No full textTo disrupt the notion that ePortfolios are primarily an assessment tool, this article-as-ePortfolio invites readers to consider what is made possible when ePortfolio initiatives lead with student learning in their structure and implementation. In addition to descriptions of both faculty and student support, we offer extended examples of ePortfolio implementation in three disparate programs at our university: Biosystems Engineering, English Education, and Nursing. To conclude, we reflect on the pedagogical challenges and opportunities that have emerged as a result of the structure and implementation of our ePortfolio initiative. Ultimately, we aim to demonstrate what is made possible for students, faculty, and curricula when ePortfolio initiatives prioritize student learning.Publishe
Developing a Juvenile Literature Collection in an Academic Library
No full textMaintaining a juvenile collection in a university setting requires a careful consideration of both the juvenile
materials market and the academic uses of juvenile materials. Because juvenile materials can range
from pre-reader items to young adult literature and may exist in different locations and under different
authorities within the academy, juvenile collection management can be a complex task. The purpose
of this chapter is to serve as a guide to collection managers charged with developing and maintaining
a juvenile collection for use by professional programs in education and librarianship. Discussions on
the nature and uses of juvenile materials in the academy, collection policies, and evaluation strategies
for juvenile collections, selection tools, and resources available to librarians, and emerging issues in
juvenile collection management are included.PublishedYe
Fast magnetosonic waves driven by shell velocity distributions
Get PDFUsing linear dispersion theory and particle-in-cell simulations, we explore the ion Bernstein instability driven by the shell-type ion velocity distribution which is related to the excitation of fast magnetosonic waves in the terrestrial magnetosphere. We first demonstrate a novel idea to construct the shell velocity distribution out of multiple Maxwellian ring-beam velocity distributions. Applying this technique, we find that the convergence of the linear theory instability can be achieved with only a moderate number of ring-beam components. In order to prove that such an approximation is legitimate and the linear theory instabilities evaluated are indeed valid, we use the exact shell distribution to carry out a number of one dimensional particle-in-cell simulations corresponding to multiple wave propagation angles adjacent to the direction at which the most unstable waves are expected to grow. The agreement between the linear dispersion analysis and the simulation results is generally very good: enhanced waves are organized along the linear theory dispersion curves in the frequency-wave number space, and relative wave amplitudes are ordered as the linear theory growth rates very well. However, the simulations show a few extra branches that are not expected from the linear dispersion analysis. A close examination of these extra branches suggests that they are not simulation artifacts and particularly related to the ring/shell-type distributions with large ring/shell speed (v>approximate to 1.5 v(A), where v(A) is the Alfven speed). In addition, our results show that substantial wave growth can occur at nonintegral harmonics of the proton cyclotron frequency at wave normal angles substantially far away from the perpendicular direction, which may provide an alternative explanation of the off-harmonic peaks of some fast magnetosonic waves observed in space.PublishedYe
The Canada Lynx (Lynx canadensis) of Isle Royale: Over-harvest, Climate Change, and the Extirpation of an Island Population
Get PDFIn the 1930s, the Canada Lynx (Lynx canadensis) was extirpated from Isle Royale, a 535-km2 island located in western Lake Superior, 22 km from the Ontario and Minnesota shorelines. The first half of the 20th century was a time of change on Isle
Royale as Caribou (Rangifer tarandus) disappeared, Coyotes (Canis latrans) briefly appeared, Moose (Alces americanus),
Grey wolves (Canis lupus), and Red Foxes (Vulpes vulpes) became established, and the habitat was altered by fire, logging,
and over-browsing. although these changes may have contributed to the demise of the Canada Lynx, our results suggest that over-harvest was a primary cause. assuming a peak carrying capacity of 75 Canada Lynx and harvest rates comparable to those reported from 1890–1935, a population viability analysis indicated that the island population had a 0% chance of surviving 50 years. The analysis also indicated that, even in the absence of harvest, the population had only a 14% chance of persistence for 250 years. however, when 10 Canada Lynx were added to the modeled population every 10th year, the probability of persistence increased to 100%. Our analyses suggest that the island’s Canada Lynx population maintained itself by periodic immigration across an ice bridge; therefore, natural recolonization should be possible. however, the probability of ice-bridge formation has declined from 0.8 in the winter of 1958–59 to 0.1 in 2012–13, likely as a result of climate change. The Isle Royale situation exemplifies another impact of climate change and the possible need to augment populations to mitigate the loss of connectivity.PublishedYe
A growing importance of large fires in conterminous United States during 1984-2012
Get PDFFire frequency, extent, and size exhibit a strong linkage with climate conditions and play a vital role in the climate system. Previous studies have shown that the frequency of large fires in the western United States increased significantly since the mid-1980s due to climate warming and frequent droughts. However, less work has been conducted to examine burned area and fire emissions of large fires at a national scale, and the underlying mechanisms accounting for the increases in the frequency of large fires are far from clear. In this study, we integrated remote-sensed fire perimeter and burn severity data sets into the Dynamic Land Ecosystem Model to estimate carbon emissions from large fires (i.e., fires with size larger than 1000acres or 4.05km(2)) in conterminous United States from 1984 to 2012. The results show that average area burned by large fires was 1.44x10(4)km(2)yr(-1) and carbon emissions from large fires were 17.65TgCyr(-1) during the study period. According to the Mann-Kendall trend test, annual burned area and pyrogenic carbon emissions presented significant upward trends at the rates of 810km(2)yr(-1) and 0.87TgCyr(-1), respectively. Characteristic fire size (fire size with the largest contribution to the total burned area) in the period of 2004-2012 increased by 176.1% compared to the period of 1984-1993. We further found that the larger fires were associated with higher burn severity and occurred more frequently in the warmer and drier conditions. This finding implies that the continued warming and drying trends in the 21st century would enhance the total burned area and fire emissions due to the contributions of larger and more severe wildfires.PublishedYe
Reproduction and development in Halocaridina rubra Holthuis, 1963 (Crustacea: Atyidae) clarifies larval ecology in the Hawaiian anchialine ecosystem
Get PDFLarvae in aquatic habitats often develop in environments different from those they inhabit as adults. Shrimp in the Atyidae exemplify this trend, as larvae of many species require salt or brackish water for development, while adults are freshwater-adapted. An exception within the Atyidae family is the "anchialine clade," which are euryhaline as adults and endemic to habitats with subterranean fresh and marine water influences. Although the Hawaiian anchialine atyid Halocaridina rubra is a strong osmoregulator, its larvae have never been observed in nature. Moreover, larval development in anchialine species is poorly studied. Here, reproductive trends in laboratory colonies over a 5-y period are presented from seven genetic lineages and one mixed population of H. rubra; larval survivorship under varying salinities is also discussed. The presence and number of larvae differed significantly among lineages, with the mixed population being the most prolific. Statistical differences in reproduction attributable to seasonality also were identified. Larval survivorship was lowest (12% settlement rate) at a salinity approaching fresh water and significantly higher in brackish and seawater (88% and 72%, respectively). Correlated with this finding, identifiable gills capable of ion transport did not develop until metamorphosis into juveniles. Thus, early life stages of H. rubra are apparently excluded from surface waters, which are characterized by lower and fluctuating salinities. Instead, these stages are restricted to the subterranean (where there is higher and more stable salinity) portion of Hawaii's anchialine habitats due to their inability to tolerate low salinities. Taken together, these data contribute to the understudied area of larval ecology in the anchialine ecosystem.PublishedYe
Look What’s under Our Tent: A Fresh Approach to Library Orientations
Get PDFAuburn University Libraries is exploring new ways to reach users by rethinking and redefining traditional library orientations and open houses. Last year’s “Tailgate at the Library” event, held at the beginning of Fall Semester, attracted 1800 participants, who enjoyed hot dogs, popcorn, and guest appearances by the Auburn cheerleaders and marching band INSIDE the library. AU librarians hosted and briefed nearly 1000 parents of incoming students at a series of “Snacks in the Stacks” sessions held during freshman orientation. New and returning students visited the Libraries’ outdoor “Information Oasis” tent during the first two days of class to pick up maps, information, and cold, bottled water. Stop by the poster, check out the photos, and learn how you can develop innovative and exciting programs to gather users under the tent of your choice
Regime transition of ion Bernstein instability driven by ion shell velocity distributions
Get PDFLinear kinetic dispersion theory is used to investigate a regime transition of the ion Bernstein instability driven by a proton velocity distribution with positive slopes with respect to the perpendicular velocity, f(p)(v(vertical bar)approximate to 0,v)/v>0. The unstable waves arising from this instability are ion Bernstein waves with proton cyclotron harmonic dispersion. However, in the inner magnetosphere, particularly inside of the plasmapause where plasmas are dominated by a cold background, the instability leads to ion Bernstein waves which approximately follow the cold plasma dispersion relation for fast magnetosonic waves and are, therefore, fast magnetosonic-like. Subsequently, the relevant waves have been termed fast magnetosonic waves and many studies have assumed the cold plasma dispersion relation to describe them. On the other hand, how the dispersion properties of ion Bernstein waves become fast magnetosonic-like has not yet been well understood. To examine this regime transition of the instability, we perform linear dispersion analyses using a two-component proton model of f(p)(v) = f(M)(v) + f(s)(v), where f(M) is a Maxwellian velocity distribution and f(s) is an isotropic shell velocity distribution. The results show that the unstable waves are essentially ion Bernstein waves; however, when the shell proton concentration becomes sufficiently small (less than 10), the unstable waves approach the cold plasma dispersion relation for fast magnetosonic waves and become fast magnetosonic-like. Although a reduced proton-to-electron mass ratio of 100 has been used for convenience, which reduces the number of unstable modes involved by lowering the lower hybrid frequency, this does not change the overall regime transition picture revealed in this study.Publishe