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A Call to Develop Course-Based Undergraduate Research Experiences (CUREs) for Nonmajors Courses
Get PDFCourse-based undergraduate research experiences (CUREs) for non-science majors (non-majors) are potentially distinct from CUREs for developing scientists in their goals, learning objectives, and assessment strategies. While national calls to improve science, technology, engineering, and mathematics education have led to an increase in research revealing the positive effects of CUREs for science majors, less work has specifically examined whether nonmajors are impacted in the same way. To address this gap in our understanding, a working group focused on nonmajors CUREs was convened to discuss the following questions: 1) What are our laboratory-learning goals for nonmajors? 2) What are our research priorities to determine best practices for nonmajors CUREs? 3) How can we collaborate to define and disseminate best practices for nonmajors in CUREs? We defined three broad student outcomes of prime importance to the nonmajors CURE: improvement of scientific literacy skills, proscience attitudes, and evidence-based decision making. We evaluated the state of knowledge of best practices for nonmajors, and identified research priorities for the future. The report that follows is a summary of the conclusions and future directions from our discussion.PublishedYe
Thermal Spikes Caused by the Urban Heat Island Effect Result in Differential Egg Survival of a Non-native Lizard (Anolis cristatellus)
Get PDFEmbryonic development in ectotherms is very sensitive to abiotic nest conditions. In reptiles, high incubation temperatures often result in relatively short incubation periods and large hatching size, but extremely high temperatures can result in cardiac arrest and death. Human altered habitats, which potentially create novel thermal conditions in the soil due to the urban heat island effect, may therefore create new selection pressures for developing embryos. The urban heat island effect can increase temperatures in cities as much as 12° C, and our preliminary data suggests that soil temperatures differ markedly between urban and natural areas in locations where reptiles deposit eggs. We measured the temperatures of potential nest sites of the Puerto Rican Crested Anole (Anolis cristatellus) in both urban and natural areas of Miami-Dade county where this lizard and several other anole species are naturalized. We bred crested anoles in the lab and subjected their eggs to 5 incubation treatments that mimic potential temperature regimes from our field data, three of which included a thermal spike 1/4 of the way through embryonic development. Preliminary results suggest that thermal spikes increase metabolism and reduce egg survival and that each are a function of the magnitude of the spike. These results suggest that urban environments create novel selection pressures that potentially result in embryonic adaptation to novel temperature regimes or in novel nest-site selection strategies by females.N
Foreshock wave interaction with the magnetopause: Signatures of mode conversion
Get PDFOur previous hybrid simulation (Shi et al., 2013) under a radial interplanetary magnetic field (IMF) and a supercritical solar wind Mach number has shown that foreshock compressional waves originated from the quasi-parallel (Q-parallel to) shock are mode converted to kinetic Alfven waves (KAWs) at the Alfven resonance surface of the subsolar magnetopause. In this paper, three-dimensional global dayside mode conversion is investigated for cases under various solar wind conditions using the global hybrid model. The global patterns and propagations of KAWs are distinguished and presented. Under a near-critical Mach number (M-A = 3), KAW structures due to mode conversion exhibit a feature of broader excitation regions in the magnetopause boundary layer (MPBL) compared to supercritical Mach number (M-A = 5) shocks. For cases with an oblique IMF with supercritical Mach numbers (M-A = 5), the amplitude of magnetosheath compressional waves is larger at the quasi-parallel shock (Q-parallel to) than at the quasi-perpendicular (Q-perpendicular to) shock. Downstream of the Q-parallel to shock, there is a general trend that the perturbations of density (N) and magnetic field (B) change from predominantly in-phase in the magnetosheath to antiphase near the MPBL. While downstream of the Q-perpendicular to shock, an antiphase relation between N and B is dominant throughout the magnetosheath and magnetopause except near the shock transition. The compressional drivers are found to reach an extended region of the magnetopause due to the combined effects of wave propagation in the plasma frame and flow convection, leading to a broad region of mode conversion at the magnetopause. Subsequently, the resulting KAWs can be carried to the regions downstream of the Q-perpendicular to shock owing to the flow convection at the magnetopause. The KAWs propagate poleward along the geomagnetic field lines and meanwhile are carried tailward by the ambient flows, and they are more intense in the downstream of Q-parallel to shocks than downstream of Q-perpendicular to shocks.Publishe
Library Workshops for Faculty Preparing for Promotion and Tenure Reviews
Get PDFFaculty who are gathering materials in preparation for a third year, tenure or promotion review may often contact their subject librarians or ILL to get publications or specific data about selected journals, including impact factors, acceptance rates, etc. In light of this, two librarians at Au-burn University designed and presented a brief workshop in 2016 on several occasions to address these common questions. Topics presented in the workshop included a review of document delivery services along with re-sources for information on journal rankings and impact factors, article citation data, journal acceptance rates, Ca-bell’s directory, Ulrichsweb, and the university’s institutional repository. Seven workshops were schedule for the fall semester 2016 on days and at times that are typically best for teaching faculty. To gather data, an anonymous voluntary online survey was designed for the participants to complete after attending a workshop. The survey data provides information about the participants intended reasons for attending, their subsequent level of confidence in using the resources and services presented, and which service or resource was the most important topic to them. These data were used by the presenters for consideration concerning changes to workshop planning and content along with how information about library resources and services for faculty may be presented to new faculty by other means or during other campus events. This poster will present information about the development of the workshop through current consideration for future workshops in light of observations and the survey data collected.unpublishedN
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.Publishe
Formation, Fate, and Impacts of Microscopic and Macroscopic Oil-Sediment Residues in Nearshore Marine Environments: A Critical Review
Get PDFCrude oil that is spilled in marine environments often interacts with suspended sediments to form residues that can impact the recovery of the affected nearshore ecosystems. When spilled oil and sediment interact, they can form either small microscopic aggregates, commonly referred to as oil-particle aggregates, or large macroscopic agglomerates, referred to as sediment-oil agglomerates or sediment-oil mats. Although these different sized oil-sediment residues have similar compositions, they are formed under different conditions and have different fates in nearshore environments; the goal of this review is to synthesize our current understanding of these two types of residues. We believe that researchers who focus solely on studying either microscopic aggregates or macroscopic agglomerates could benefit from understanding the research findings available in the other field. In this study, we compare and contrast various processes that control the formation, fate, and impacts of these two types of residues in nearshore environments and point out some of the knowledge gaps in this field. Additionally, these residues have been referred to by many names in the past, leading to confusion and misconceptions at times. In this effort, we recommend a uniform nomenclature to distinguish them based on their physical size. Our overall aim is to bridge the gap between microscopic and macroscopic oil-sediment residue literature to foster a robust exchange of ideas, which we believe can lead to the development of efficient strategies for managing oil spills that affect nearshore environments.PublishedYe
'A Being Apart': Sympathy and Distance in Middlemarch (Prize Essay)
No full textArticle from the George Eliot Review, digitized and hosted by the George Eliot Review Online.Publishe
Chemometric modeling of thermogravimetric data for the compositional analysis of forest biomass
Get PDFThe objective of this study was to investigated the use of chemometric modeling of thermogravimetric (TG) data as an alternative approach to estimate the chemical and proximate (i.e. volatile matter, fixed carbon and ash contents) composition of lignocellulosic biomass. Since these properties affect the conversion pathway, processing costs, yield and / or quality of products, a capability to rapidly determine these for biomass feedstock entering the process stream will be useful in the success and efficiency of bioconversion technologies. The 38-minute long methodology developed in this study enabled the simultaneous prediction of both the chemical and proximate properties of forest-derived biomass from the same TG data. Conventionally, two separate experiments had to be conducted to obtain such information. In addition, the chemometric models constructed with normalized TG data outperformed models developed via the traditional deconvolution of TG data. PLS and PCR models were especially robust in predicting the volatile matter (R2–0.92; RPD– 3.58) and lignin (R2–0.82; RPD– 2.40) contents of the biomass. The application of chemometrics to TG data also made it possible to predict some monomeric sugars in this study. Elucidation of PC loadings obtained from chemometric models also provided some insights into the thermal decomposition behavior of the chemical constituents of lignocellulosic biomass. For instance, similar loadings were noted for volatile matter and cellulose, and for fixed carbon and lignin. The findings indicate that common latent variables are shared between these chemical and thermal reactivity properties. Results from this study buttresses literature that have reported that the less thermally stable polysaccharides are responsible for the yield of volatiles whereas the more recalcitrant lignin with its higher percentage of elementary carbon contributes to the yield of fixed carbon.Ye