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ePortfolio Assessment as Faculty Development: Gathering Reliable Data and Increasing Faculty Confidence
Get PDFAn ePortfolio Assessment Institute (AI) structured as a faculty development opportunity was undertaken to increase faculty confidence in teaching and assessing ePortfolios and to collect reliable data about student performance on four learning outcomes associated with an institutionwide ePortfolio initiative. Faculty raters participated in the two-day AI and received more than a day of training to use a summative rubric consistently. Faculty were asked to rate their own confidence in teaching and scoring each of the outcomes before coming to the AI and at the end of the AI. Generalizability-theory was used to estimate rater pair consistency. After establishing that the data were reliable, we analyzed the data to reveal a wide range in performance across ePortfolios. The survey of faculty showed statistically significant improvement in confidence across both teaching and evaluating for all outcomes. The study thus demonstrates that structuring an AI as a professional development activity increases faculty confidence in teaching and assessing outcomes related to ePortfolios. The study also demonstrates that ePortfolio initiatives can be successfully assessed even if commercial platforms that standardize and privilege assessment are not used and the ePortfolios themselves remain in the control of students rather than the institution.PublishedYe
Longitudinal Analysis of a Diversity Support Program in Biology: A National Call for Further Assessment
Get PDFNational calls to improve the performance and persistence of students from historically underrepresented backgrounds in science have led to a surge of research on inclusive, evidence-based teaching methods. Less work has revealed the effects of diversity support initiatives that improve campus climate and community cohesion. Here, we examine whether participation in the Biology Scholars Program (BSP) at Cornell University-a diversity support program at a prominent university-affects underrepresented racial minority (URM) student performance. We found that BSP participants are less academically prepared when they enter college but typically have GPAs similar to those of their non-BSP counterparts at graduation, thereby closing achievement gaps. Although the BSP appears to help URM students, we cannot assert that the BSP alone is responsible for these effects; future work should isolate effective strategies that contribute to student success. In response to these results, we lay out strategies that support programs could implement to maximize positive impactsPublishedYe
Can mixed assessment methods make biology classes more equitable
Get PDFMany factors have been proposed to explain the attrition of women in science, technology, engineering and math fields, among them the lower performance of women in introductory courses resulting from deficits in incoming preparation. We focus on the impact of mixed methods of assessment, which minimizes the impact of high-stakes exams and rewards other methods of assessment such as group participation, low-stakes quizzes and assignments, and in-class activities. We hypothesized that these mixed methods would benefit individuals who otherwise underperform on high-stakes tests. Here, we analyze gender-based performance trends in nine large (N > 1000 students) introductory biology courses in fall 2016. Females underperformed on exams compared to their male counterparts, a difference that does not exist with other methods of assessment that compose course grade. Further, we analyzed three case studies of courses that transitioned their grading schemes to either de-emphasize or emphasize exams as a proportion of total course grade. We demonstrate that the shift away from an exam emphasis consequently benefits female students, thereby closing gaps in overall performance. Further, the exam performance gap itself is reduced when the exams contribute less to overall course grade. We discuss testable predictions that follow from our hypothesis, and advocate for the use of mixed methods of assessments (possibly as part of an overall shift to active learning techniques). We conclude by challenging the student deficit model, and suggest a course deficit model as explanatory of these performance gaps, whereby the microclimate of the classroom can either raise or lower barriers to success for underrepresented groups in STEM.PublishedYe
Spectral properties and associated plasma energization by magnetosonic waves in the Earth's magnetosphere: Particle-in-cell simulations
Get PDFIn this paper, we perform a 1-D particle-in-cell (PIC) simulation model consisting of three species, cold electrons, cold ions, and energetic ion ring, to investigate spectral structures of magnetosonic waves excited by ring distribution protons in the Earth's magnetosphere, and dynamics of charged particles during the excitation of magnetosonic waves. As the wave normal angle decreases, the spectral range of excited magnetosonic waves becomes broader with upper frequency limit extending beyond the lower hybrid resonant frequency, and the discrete spectra tends to merge into a continuous one. This dependence on wave normal angle is consistent with the linear theory. The effects of magnetosonic waves on the background cold plasma populations also vary with wave normal angle. For exactly perpendicular magnetosonic waves (parallel wave number k(parallel to) = 0), there is no energization in the parallel direction for both background cold protons and electrons due to the negligible fluctuating electric field component in the parallel direction. In contrast, the perpendicular energization of background plasmas is rather significant, where cold protons follow unmagnetized motion while cold electrons follow drift motion due to wave electric fields. For magnetosonic waves with a finite k(parallel to), there exists a nonnegligible parallel fluctuating electric field, leading to a significant and rapid energization in the parallel direction for cold electrons. These cold electrons can also be efficiently energized in the perpendicular direction due to the interaction with the magnetosonic wave fields in the perpendicular direction. However, cold protons can be only heated in the perpendicular direction, which is likely caused by the higher-order resonances with magnetosonic waves. The potential impacts of magnetosonic waves on the energization of the background cold plasmas in the Earth's inner magnetosphere are also discussed in this paper.PublishedYe
Ring/Shell Ion Distributions at Geosynchronous Orbit
Get PDFOne year's worth of plasma observations from geosynchronous orbit is examined for ion distributions that may simultaneously be subject to the ion Bernstein (IB) instability (generating fast magnetosonic waves) and the Alfven cyclotron (AC) instability (generating electromagnetic ion cyclotron waves). Confirming past analyses, distributions with robust partial derivative fp(v(perpendicular to))/partial derivative v(perpendicular to) > 0 near v(|)| = 0, which we denote as ring/shell distributions, are commonly found primarily on the dayside of the magnetosphere. A new approach to high-fidelity representation of the observed ring/shell distribution functions in a form readily suited to both analytical moment calculation and linear dispersion analysis is presented, which allows statistical analysis of the ring/shell properties. The ring/shell temperature anisotropy is found to have a clear upper limit that depends on the parallel beta of the ring/shell (beta|| r) in a manner that is diagnostic of the operation of the AC instability. This upper limit is only reached in the postnoon events, which are primarily produced by the energy-and pitch angle-dependent magnetic drifts of substorm-injected ions. Further, it is primarily the leading edge of such injections, where the distribution is strongly ring-like, that the AC instability appears to be operating. By contrast, the ratio of the ring energy to the Alfven energy remains well within the range of 0.25-4.0 suitable for IB instability throughout essentially all of the events, except those that occur in denser cold plasma of the outer plasmasphere. Plain Language Summary One year's worth of plasma observations from geosynchronous orbit is examined for ion distributions that may simultaneously be subject to the ion Bernstein (IB) instability (generating fast magnetosonic waves) and the Alfven cyclotron (AC) instability (generating electromagnetic ion cyclotron waves). Confirming past analyses, ring/shell distributions are commonly found primarily on the dayside of the magnetosphere. A new approach to high-fidelity representation of the observed ring/shell distribution functions allows statistical analysis of the ring/shell properties. Clear evidence is found for the operation of the AC instability, but only in the afternoon events, which are primarily produced by the energy-and pitch angle-dependent magnetic drifts of substorm-injected ions. Further, it is primarily at the leading edge of such injections, where the distribution is strongly ring-like, that the AC instability appears to be operating. By contrast, the IB instability seems to be driven throughout essentially all of the events, except those that occur in denser cold plasma of the outer plasmasphere. These results suggest that fast magnetosonic waves should typically dominate over electromagnetic ion cyclotron waves during most substorm injections.PublishedYe
Cleaning Data, or More Neat Excel Tricks to Make it Easier
Get PDFLibrarians deal with data from a variety of sources and each source can be unique in how it presents in Excel. Cleaning data is inevitable. Here are some basic and not so basic tips and tricks to deal with disappearing leading zeros, consistency in case, trimming those fields, tables for all, and how pivot tables can be your friend
Cross-scale observations of the 2015 St. Patrick's day storm: THEMIS, Van Allen Probes, and TWINS
Get PDFWe present cross-scale magnetospheric observations of the 17 March 2015 (St. Patrick's Day) storm, by Time History of Events and Macroscale Interactions during Substorms (THEMIS), Van Allen Probes (Radiation Belt Storm Probes), and Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS), plus upstream ACE/Wind solar wind data. THEMIS crossed the bow shock or magnetopause 22 times and observed the magnetospheric compression that initiated the storm. Empirical models reproduce these boundary locations within 0.7 R-E. Van Allen Probes crossed the plasmapause 13 times; test particle simulations reproduce these encounters within 0.5 R-E. Before the storm, Van Allen Probes measured quiet double-nose proton spectra in the region of corotating cold plasma. About 15 min after a 0605 UT dayside southward turning, Van Allen Probes captured the onset of inner magnetospheric convection, as a density decrease at the moving corotation-convection boundary (CCB) and a steep increase in ring current (RC) proton flux. During the first several hours of the storm, Van Allen Probes measured highly dynamic ion signatures (numerous injections and multiple spectral peaks). Sustained convection after similar to 1200 UT initiated a major buildup of the midnight-sector ring current (measured by RBSPA), with much weaker duskside fluxes (measured by RBSPB, THEMISa and THEMIS d). A close conjunction of THEMISd, RBSPA, and TWINS1 at 1631 UT shows good three-way agreement in the shapes of two-peak spectra from the center of the partial RC. A midstorm injection, observed by Van Allen Probes and TWINS at 1740 UT, brought in fresh ions with lower average energies (leading to globally less energetic spectra in precipitating ions) but increased the total pressure. The cross-scale measurements of 17March 2015 contain significant spatial, spectral, and temporal structure.Publishe
Changing User Needs, Changing Librarian Roles: A Qualitative Study
Get PDFThis qualitative study explored possible adaptions to the roles of librarians working in the reference department of a southeastern academic research library. The study used focus groups to investigate new directions for open positions within the department, as well as to question librarians about potential unmet user needs. The investigators will discuss themes that emerged, participants’ suggestions for dealing with change, and next steps for the department.N
Global images of trapped ring current ions during main phase of 17 March 2015 geomagnetic storm as observed by TWINS
Get PDFA unique view of the trapped particles in the inner magnetosphere provided by energetic neutral atom (ENA) imaging is used to observe the dynamics of the spatial structure and the pitch angle anisotropy on a global scale during the last 6h of the main phase of a large geomagnetic storm (minimum SYM-H=-230nT) that began on 17 March 2015. Ion flux and pressure anisotropy obtained from Two Wide-angle Imaging Neutral-atom Spectrometers (TWINS) ENA images are shown. The ion flux shows two peaks, an inner one at approximately radii=3-4 R-E in the dusk-to-midnight sector and an outer peak at radii=8-9 R-E prior to midnight. The inner peak is relatively stationary during the entire period with some intensification during the final steep decline in SYM-H to its minimum. The outer peak shows the significant temporal variation brightening and dimming and finally disappearing at the end of the main phase. The pressure anisotropy shows the expected perpendicular pitch angles inside of L=6 but shows parallel pitch angles at greater L values. This is interpreted as consistent with pitch angle-dependent drift as modeled in the Tsy05 magnetic field and Comprehensive Inner Magnetosphere-Ionosphere simulations. The TWINS results are compared directly with Radiation Belt Storm Probes Ion Composition Experiment (RBSPICE)-A measurements. Using 15min snapshots of flux and pressure anisotropy from TWINS along the path of RBSPICE-A during the 6h focused upon in this study, the essential features displayed in the TWINS global images are supported.Publishe