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George Eliot's ‘Network’ of Readers
No full textArticle from the George Eliot Review, digitized and hosted by the George Eliot Review Online.Publishe
Multi-Event Studies of Sudden Energetic Electron Enhancements in the Inner Magnetosphere and Its Association With Plasmapause Positions
Get PDFSudden enhancements of energetic electrons (tens of keV to <500 keV) at low L-shells have been frequently observed by Van Allen Probes. It is, however, still unclear how deep these electrons can reach and what the responsible mechanisms are. Here we seek to determine the inner boundary of initial enhancements of these energetic electrons and its link with the plasmapause location to offer a new, insightful perspective on this topic. Previous statistical studies have revealed a remarkably consistent observation that initial enhancements of energetic electrons occur mostly at higher L-shell than the innermost plasmapause locations (L-pp), though a few outlier events were also identified. In this study, we examine the identified outlier events where electron enhancements were reported inside the plasmapause (either in situ L-pp or simulated innermost L-pp). More detailed investigation indicates that the appearance of enhancements inside the in situ L-pp is often associated with duskside observations where the actual initial enhancement likely occurs somewhere else, outside the innermost plasmapause location. We thereby urge caution when using the relationship between the observed enhancement locations and the in situ L-pp to infer the effect of electric fields on energetic electrons. In summary, our findings suggest that the innermost L-pp remains the innermost limit of the initial sudden enhancements of energetic electrons. Combining with phase space density analysis, our result implies the role of a large-scale electric field that leads to sudden electron enhancements and the erosion of the plasmasphere.PublishedYe
Evaluation of dissolved carbon dioxide to stimulate emergence of red swamp crayfish Procambarus clarkii (Decapoda: Cambaridae) from infested ponds
Get PDFInvasive crayfish have adverse effects on habitats and native species. Control of invasive crayfish populations is a major challenge facing natural resource managers. This study evaluated the effectiveness and optimal conditions for the control agent carbon dioxide (CO2), which can be diffused into water to facilitate capture of red swamp crayfish (Procambarus clarkii; RSC). The efficacy of CO2 shows promise in its use for a variety of invasive aquatic species. Here, we evaluate CO2’s ability to stimulate movements towards the shoreline and/or induce complete terrestrial emergence from outdoor ponds. Twelve pond trials were conducted using three, 0.02-ha experimental ponds at Auburn University, Alabama, USA. Silt fencing was installed on dry land around the perimeter of each pond with the lower 0.3 m of fencing accordion-folded to provide shelter and a collection point for emerging crayfish. Each pond was stocked with 100 RSC before testing. Experimental treatment ponds were then injected with gaseous CO2 using porous air diffusers, whereas control ponds (C ponds) received no CO2. Multiple water quality parameters were monitored hourly. Three independent treatment scenarios with CO2 diffusion were crayfish captured at the end of trial only (F: final), crayfish captured hourly (H: hourly), and incorporation of continuous inflow of fresh water at a flow rate of 0.2 L/s into the central catch basin to serve as a refuge with crayfish captured hourly (R: refuge). In control ponds, crayfish were captured at the end of trial only. In F ponds, CO2 diffusion for approximately five hours caused a mean of 12% of total crayfish to emerge from the water. However, capture efficiency was increased to a mean of 45% of total crayfish by increasing collection frequency to every hour and netting submerged crayfish near the water edge in addition to capturing terrestrially emerged crayfish. Presence of a freshwater inflow reduced capture efficiency in R ponds relative to H ponds. Odds of capturing crayfish increased with increasing water temperature, CO2 concentration, crayfish mass, and with decreasing pH. Based on results, we provide a set of predictive equations as well as interactive calculators to help natural resource managers explore several environmental and treatment-related scenarios that predict changes in capture probability in small research ponds. Carbon dioxide shows promises as a tool to increase capture rate of RSC. It is not likely to be 100% effective by itself, but could be a useful component of an integrated management strategy
Re-Reconnection Processes of Magnetopause Flux Ropes: Three-Dimensional Global Hybrid Simulations
Get PDFMagnetopause flux ropes (FRs) play a crucial role in the transport of energy and plasma from the solar wind to the Earth's magnetosphere. Once formed by multiple X-line reconnection, the FRs move poleward, during which they can coalesce with each other through a re-reconnection process. The poleward moving FRs eventually coalesce into the cusp regions, through another re-reconnection process. In this paper, using three-dimensional (3-D) global hybrid simulations, we study the two re-reconnection processes of magnetopause FRs by examining the topological changes of magnetic field lines. These re-reconnection processes are essentially 3-D. Two FRs coalesce with each other and form two new FRs (instead of one new FR in the two-dimensional regime). When FRs move close to the cusp region, their field lines can reconnect with the cusp field lines so that the FRs can break into two shorter ones. The two re-reconnection processes increase the plasma energy and the magnetic flux connected to the Earth, which favors particle and energy transport toward the Earth's magnetosphere.PublishedYe
Digital Ethics in ePortfolios: Developing Principles, Strategies, and Scenarios
Get PDFIn response to rising concerns about digital ethics in ePortfolio practice, the Association for Authentic, Experiential, Evidence-Based Learning (AAEEBL) created a Digital Ethics Task Force charged with researching and articulating research-based practices for ePortfolios. After year one, the Task Force released the Digital Ethics Principles in ePortfolios: Version 1. This article describes the process used to recruit Task Force members and develop the resulting principles. In using the Task Force as a model for international collaboration and digital composition, the final section of this paper identifies key takeaways for the field and proposes future opportunities for research in digital ethics and ePortfolio practice.PublishedYe
Amphibian Speciation Rates Support a General Role of Mountains as Biodiversity Pumps
Get PDFContinental mountain areas cover 80% of global terrestrial diversity. One prominent hypothesis to explain this pattern proposes that high mountain diversities could be explained by higher diversification rates in regions of high topographic complexity (HTC). While high speciation in mountains has been detected for particular clades and regions, the global extent to which lineages experience faster speciation in mountains remains unknown. Here we addressed this issue using amphibians as a model system (>7,000 species), and we found that families showing high speciation rates contain a high proportion of species distributed in mountains. Moreover, we found that lineages inhabiting areas of HTC speciate faster than lineages occupying areas that are topographically less complex. When comparing across regions, we identified the same pattern in five biogeographical realms where higher speciation rates are associated with higher levels of complex topography. Low-magnitude differences in speciation rates between some low and high complex topographies suggest that high mountain diversity is also affected by low extinction and/or high colonization rates. Nevertheless, our results bolster the importance of mountains as engines of speciation at different geographical scales and highlight their importance for the conservation of global biodiversity.PublishedYe
Review: Sylvere Monod and Alain Jumeau, Middlemarch precede de Le Moulin sur la Floss
No full textArticle from the George Eliot Review, digitized and hosted by the George Eliot Review Online.Publishe
Digital ethics in ePortfolios: Version 2.0, resource development by the AAEEBL Digital Ethics ePortfolio Task Force in 2021
No full textThe Digital Ethics ePortfolio Task Force for the Association for Authentic, Experiential, & Evidence-Based Learning (AAEEBL) continued to bring together international ePortfolio scholars and practitioners to establish research-based digital practices for ePortfolio stakeholders, including institutions, students, educators, and administrators. Phase one developed an online interactive resource, Digital Ethics Principles in ePortfolios: Version 1, which outlines strategies, scenarios, and resources around ten principles. This second iteration adds additional principles related to ePortfolio evaluation practices; practices that encourage diversity, equity, inclusion, and belonging; and visibility of labour. In Digital Ethics Principles in ePortfolios: Version 2, revisions to the original ten principles integrate information regarding eProfessionalism and legal issues that can intersect with ePortfolio practice. The original online visual interface has also been upgraded. This expanded version of the principles document continues to articulate explicit and applicable practices relevant to ePortfolio creators, educators, platform creators, and administrators of programs and institutions with ePortfolio requirements.PublishedYe
