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Assessment Institute Insights: Preparing for the 2021 HIPs in The States Track at the Assessment Institute
Get PDFJoining the Assessment Institute and expanding the reach of HIPs in the States has provided opportunities to come together as a community and welcome colleagues from other tracks who are new to HIPs.PublishedN
Microaggressions, harassment, and workplace stress
Get PDFA panel presentation about microaggressions, harassment, which can contribute to workplace stress. Potential strategies for mitigating the negative effects of experiencing these phenomena are also presented. Part of the REFORMA VII pre-conference, "Bridging the Gap: In Support of Women in Librarianship.
Modeling the Dynamics of Radiation Belt Electrons With Source and Loss Driven by the Solar Wind
Get PDFA radial diffusion model directly driven by the solar wind is developed to reproduce MeV electron variations between L = 2-12 (L is L* in this study) from October 2012 to April 2015. The radial diffusion coefficient, internal source rate, quick loss due to EMIC waves, and slow loss due to hiss waves are all expressed in terms of the solar wind speed, dynamic pressure, and interplanetary magnetic field (IMF). The model achieves a prediction efficiency (PE) of 0.45 at L = 5 and 0.51 at L = 4 after converting the electron phase space densities to differential fluxes and comparing with Van Allen Probes measurements of 2 and 3 MeV electrons at L = 5 and L = 4, respectively. Machine learning techniques are used to tune parameters to get higher PE. By tuning parameters for every 60-day period, the model obtains PE values of 0.58 and 0.82 at L = 5 and L = 4, respectively. Inspired by these results, we divide the solar wind activity into three categories based on the condition of solar wind speed, IMF Bz, and dynamic pressure, and then tune these three sets of parameters to obtain the highest PE. This experiment confirms that the solar wind speed has the greatest influence on the electron flux variations, particularly at higher L, while the dynamic pressure has more influence at lower L. Also, the PE at L = 4 is mostly higher than those at L = 5, suggesting that the electron loss due to the magnetopause shadowing combined with the outward radial diffusion is not well captured in the model.PublishedYe
Magnitude and Predictability of pH Fluctuations Shape Plastic Responses to Ocean Acidification
Get PDFPhenotypic plasticity is expected to facilitate the persistence of natural populations as global change progresses. The attributes of fluctuating environments that favor the evolution of plasticity have received extensive theoretical investigation, yet empirical validation of these findings is still in its infancy. Here, we combine high-resolution environmental data with a laboratory-based experiment to explore the influence of habitat pH fluctuation dynamics on the plasticity of gene expression in two populations of the Mediterranean mussel, Mytilus galloprovincialis. We linked differences in the magnitude and predictability of pH fluctuations in two habitats to population-specific gene expression profiles in ambient and stressful pH treatments. Our results demonstrate population-based differentiation in gene expression plasticity, whereby mussels native to a habitat exhibiting a large magnitude of pH fluctuations with low predictability display reduced phenotypic plasticity between experimentally imposed pH treatments. This work validates recent theoretical findings on evolution in fluctuating environments, suggesting that the predictability of fluctuating selection pressures may play a predominant role in shaping the phenotypic variation observed across natural populations.PublishedYe
Examining Audience Reaction to B2B Content Marketing Delivered via Social Media
Get PDFSocial media provide multiple platforms and tactics to reach business-to-business (B2B) audiences with content they may rely upon to make purchasing decisions. But while content marketing has drawn some academic interest over the past decade, particularly in the field of media effects where audience reactions are studied with traditional theoretical frameworks, there is very little scholarly research examining how content marketing in social media influences audiences, particularly with regard to purchase decisions. In the highly competitive B2B marketing space, where those making purchasing decisions must be well informed and expect brands to provide content to that end, audience reaction and tactics are especially valuable to understand.Ye
Investigation of the Interaction Between Magnetosheath Reconnection and Magnetopause Reconnection Driven by Oblique Interplanetary Tangential Discontinuity Using Three-Dimensional Global Hybrid Simulation
Get PDFMagnetosheath reconnection due to the interaction of an interplanetary directional discontinuity with the bow shock and Earth's magnetosphere under an initially northward interplanetary magnetic field (IMF) has been investigated in previous simulations (e.g., Guo et al., 2018, https://doi.org/10.1029/2018ja025679). Under an initially southward IMF, the magnetosheath reconnection could interact with reconnection at the magnetopause. In this study, using three-dimensional (3D) globalscale hybrid simulations, we present cases with incoming tangential discontinuities (TDs) in an initially southward IMF, which possess various magnetic field rotation angles (Delta Phi) and half-width (w), to study the effects of pre-existing magnetopause reconnection on the formation of magnetosheath flux ropes, as well as the subsequent interaction between the magnetopause reconnection and magnetosheath reconnection, with downstreams of both Quasi-perpendicular (Q-perpendicular to) and Quasi-parallel (Q-II) shock examined. The initial IMF is assumed to be oblique, with a finite B-x and B-z similar to that in Guo et al. (2018), https://dot org/10.1029/2018ja025679 but with a southward B-z < 0. Compared with the cases with an initially northward IMF, magnetopause reconnection weakens the compression processes of the TD and leads to less frequent reconnection in the magnetosheath. The existence and the structure of magnetosheath reconnection are found to strongly depend on the parameters w and Delta Phi of the TD. When interacting with the magnetopause reconnection, the magnetosheath flux ropes can re-reconnect with the geomagnetic dipole field lines, forming new structures of magnetopause flux ropes. The resulting evolution of flux rope configuration is illustrated.PublishedYe
Data for: Harmful algal blooms and cyanotoxins in Lake Amatitlán, Guatemala, coincided with ancient Maya occupation in the watershed
No full textPublishedYe
Propagation of Electromagnetic Ion Cyclotron Waves in a Dipole Magnetic Field: A 2-D Hybrid Simulation
Get PDFElectromagnetic ion cyclotron (EMIC) waves are one commonly observed plasma waves in the Earth's inner magnetosphere and play a crucial role in particle dynamics in the radiation belt and ring current. EMIC waves are excited by a proton temperature anisotropy and generally have a left-handed polarization, however satellite observations have usually reported the existence of linearly polarized EMIC waves in the inner magnetosphere. In this paper, we employ a two-dimensional (2D) hybrid code in a dipole field (gcPIC-hybrid) to simulate the propagation of EMIC waves from the equatorial source region. We track one single EMIC wave packet and analyze how its properties evolve along its trajectory. In diagnosing the wave normal angle (WNA) of the packet, we propose a novel method called Wave Front Shape Identification (WFSI). The ellipticity can also been calculated after we know the WNA. By comparing the ellipticity calculated from the linear theory and the ellipticity diagnosed from the simulation, we conclude that in a proton-electron plasma, EMIC waves would turn from a left-handed polarization to a linear polarization solely due to the propagation effect when the waves propagate toward higher latitudes and become oblique. We also find that the peak frequency of the wave packet (the wave mode with the maximum amplitude) decreases when propagating toward higher latitudes, which is due to different growth and damping behavior of different modes.PublishedYe
Data for: Evaluation of dissolved carbon dioxide to stimulate emergence of red swamp crayfish Procambarus clarkii (Decapoda: Cambaridae) from invaded ponds
No full textInvasive 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 an average of 12% of total crayfish to emerge from the water. However, capture efficiency was increased to an average 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. However, it is not likely to be effective by itself, but it could be added to an integrated management strategy.Ye
Review: Constance M Fulmer, George Eliot’s Moral Aesthetic: Compelling Contradictions
No full textArticle from the George Eliot Review, digitized and hosted by the George Eliot Review Online.Publishe