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The advent of digital wildlife cameras has led to a dramatic increase in the use of camera traps for mammalian biodiversity surveys, ecological studies and occupancy analyses. For cryptic mammals such as mice and shrews, whose small sizes pose many challenges for unconstrained digital photography, use of camera traps remains relatively infrequent. Here we use a practical, low-cost small mammal camera platform (the “MouseCam”) that is easy and inexpensive to fabricate and deploy and requires little maintenance beyond camera service. We tested the MouseCam in two applications: a study of small mammal species composition on two transects across a barrier island and a study of small mammal occupancy along a subtle elevation gradient in a mainland forest. The MouseCam was reasonably efficient, with over 78% of all images containing a recognizable small mammal (mouse, vole, rat or shrew). We obtained an accurate estimate of species composition on the island transects, as indicated by comparison with both concurrent and long-term trapping records for the same transects. MouseCams required a smaller expenditure of personnel and transportation resources than would be required for live trapping. They also detected subtle elevation-related differences in species occupancy in the mainland forest for the marsh rice rat, with the species occurring at lower elevations in the forest. This is consistent with the typical occurrence of the marsh rice rat in marshes and wetlands. We also tested devices (barriers, runways) designed to reduce disturbance by mesopredators (e.g., raccoons). Adding an internal barrier to the MouseCam did not reduce use by white-footed mice, whereas adding an external runway did. We believe specialized small mammal camera-based sensors may have wide applicability in field studies of small mammal distribution, abundance and biology. 

Abstract Rainfall in the tropics has been shown to be produced either by isolated but intense convective systems (showersregime) or widespread but weaker systems (rainsregime). We examine significant rainfall systems observed in the OTREC project (Organization of Tropical East Pacific Convection) in order to tease out the physical mechanisms differentiating these two regimes. We find that rains occur in very moist environments, typically with weak conditional instability. In contrast, showers develop in drier environments with larger instability. Spectral weak temperature gradient numerical calculations show that showers are associated with episodic rainfall separated by significant quiescent periods, whereas rains produce continuous simulated rainfall after a spinup period. Mass flux profiles of showers and rains are very different, resulting in different effects on the large scale environment. 

This is a board presentation at the 2023 ASEE Annual Conference describing the HSI Implementation and Evaluation Project: Commitment to Learning Instilled by Mastery-Based Undergraduate Program (CLIMB-UP). Commitment to Learning Instilled by a Mastery-Based Undergraduate Program (CLIMBUP) is an NSF IUSE:HSI project centered on re-designing courses with high non-completion rates (C- or lower) that have implications towards students’ graduation, transfer ability and retention. Despite decades of effort to create active, inquiry-based learning practices in classrooms, our institution continues to see equity gaps and many required courses with noncompletion rates exceeding 50%. Grading practices have been identified as one of the main culprits in the persistence of equity gaps. As a Hispanic Serving Institution, we recognize and value the diversity of experience that our students bring to our campuses and are committed to utilizing their strengths by creating datadriven, equitable grading practices that give students space to take risks and bring alternative viewpoints to our classrooms and be rewarded. We believe a Mastery-Based Grading (MBG) approach can address problems that a traditional grading approach has caused. The CLIMB-UP project is building the infrastructure to support and train STEM faculty (both tenure-line and adjuncts) to redesign and teach a Mastery-Based Graded (MGB) course, and is conducting research on faculty experiences and on the change in student attitudes, mindsets, and outcomes. 

A method is presented which allows for the numerical computation of the stress-energy tensor for a quantized massless minimally coupled scalar field in the region outside the event horizon of a 4D Schwarzschild black hole that forms from the collapse of a null shell. This method involves taking the difference between the stress-energy tensor for the in state in the collapsing null shell spacetime and that for the Unruh state in Schwarzschild spacetime. The construction of the modes for the {\it in} vacuum state and the Unruh state is discussed. Applying the method, the renormalized stress-energy tensor in the 2D case has been computed numerically and shown to be in agreement with the known analytic solution. In 4D, the presence of an effective potential in the mode equation causes scattering effects that make the the construction of the in modes more complicated. The numerical computation of the in modes in this case is given. 

Abstract Convection observed in the OTREC field program in the tropical east Pacific and southwest Caribbean is simulated using a cloud‐resolving model employing the weak temperature gradient approximation. Simulations are made using reference profiles derived from three‐dimensional variational analyses of dropsonde data selected for different ranges of saturation fraction, a kind of column relative humidity. For each of these humidity ranges, two simulations are performed, one with ventilation of the model domain by the ambient wind (a new model feature) and one without this ventilation. The model results using ventilation are much closer to observation than those without ventilation, especially for drier environments. These results have strong implications for the distribution of ITCZ convection in the east Pacific and for the construction of cumulus parameterizations.