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Peer mentoring programs can provide instructional support for graduate teaching assistants (GTAs) (Rogers & Yee, 2018; Yee & Rogers, 2017) through more specialized and detailed discussions than just working with faculty (Speer et al., 2015; Yee & Rogers, 2016). Lanius et al. (2022) explored how mentees and mentors participating in a comprehensive multi-component GTA pedagogical training program, Promoting Success in Undergraduate Mathematics Through Graduate Teacher Training (Harrell-Williams et al., 2020), at three universities at the start of an academic year conceptualized the role of an effective mentor. In this poster, we explore whether this conceptualization of the mentor role changed over the course of the academic year after participation in components of the training program: a GTA Teaching Seminar, Critical Issues Seminar, and peer mentoring (including mentor training). 

Bending permits soft arms to access a workspace that is not colinear with the initial arm axis; the size and shape of this space depends on the characteristics of the soft arm. Soft bending actuators and arms have developed for specific applications, but not characterized for the general relationship between design variables and performance. This paper defines a class of soft bending arms based on its design, considering the arm as a system constructed from many contracting actuators organized into segments. A modular segment design is presented, and seven variants of this design were constructed and tested for bend radius, bend direction, lateral stiffness and contraction. The variants isolate system parameters, in this case, arm radius and number of actuators within a given segment, to quantify how these parameters affect performance. A trade-off was found between lateral stiffness and bend radius, which can be controlled by altering the arm radius or the number of actuators. Bend direction was found to be coupled to both bend radius and arm load. Finally, a three-segment arm following a bio-inspired design is presented to demonstrate how the experimental results apply to soft robot system design. 

Individual soft actuators have been developed for elongation, contraction, bending and twist, but these actuators and their combinations have yet to demonstrate the range and flexibility of motion seen in common sources of biological inspiration, such as cephalopods. This paper presents a method for torsion control via sets of opposing contracting actuators wound helically around a cylindrical structure. By shortening one set of actuators, twist is developed, similar to the oblique muscles within octopus arms. The addition of helical actuators to systems with longitudinal and transverse actuators will enable control over orientation of the arm and antagonistic stiffening. A geometric model is used to quantify best-case developed twist, representing application to a constant dimension cylinder. This model is validated experimentally using a cable-driven prototype on a rigid cylinder with no torsional stiffness. To evaluate the interaction with a system of actuators, a mechanics model of the torsion actuators wrapped around a deformable center is proposed. This model is used to extend the solution given by W.M. Kier [Zoological Journal of the Linnean Society, Vol. 83, No. 4, 307-324, 1985], and shows that while significant twist can be lost to deformations of the internal structure, those with a Poisson’s ratio approaching ν = 0.5 mitigate this loss. Finally, the feasibility of the concept is demonstrated with McKibben actuators wound around foam. 

Abstract Prodigious amounts of the hydroxyl radical (OH) are generated in the laboratory on tree leaves by corona discharges, which also occur on trees during thunderstorms. Production rates of OH and HO₂depend on the applied electric field generating the corona discharge, leaf dryness, and the presence of liquid water on the leaf. However, they are independent of leaf type and corona discharge polarity for a given corona ultraviolet (UV) flux. Production rates of OH, HO₂, and O₃strongly correlate with corona UV flux. Although the contribution of corona‐produced OH to total global OH production is unlikely to be important, corona‐generated OH is likely a few orders of magnitude greater than oxidation by known processes in the vicinity of the affected leaves, potentially influencing atmospheric oxidation and tree and forest ecology.