The Speaker: The Tradition and Practice of Public Speaking

Speech is both a skill and a field of study. Today, however, the rich tradition of speech communication is either reduced to a few quick mentions of Aristotle and Cicero or lost altogether. Why have we forgotten this history, and more importantly, why are we not sharing these origins with our students? This volume brings tradition to the forefront of public speaking instruction through the lens of skills-centered pedagogy. It will help students understand the “why” behind the “how” of effective public speaking

Dynamic Mechanical Analysis Piezoelectric Design

This project is a continuation into the design and implementation of a Dynamic Mechanical Analysis (DMA) device that will be used to conduct high frequency testing on tire tread compounds. The design requirements necessary were to design a device that will produce a target frequency of 10 kHz with a 0.05% strain, while being at room temperature. The 3-D model developed by the previous year’s students was improved upon and new parts were designed as well. The assemblies (most importantly the connector piece) were 3-D modeled using Creo Parametric and analyzed with COMSOL Multiphysics. A new design involving flexures was also designed to be used in the third year of the project to help increase the overall frequency of the assembly while adding support to keep the assembly in place. Different designs were examined to determine the best design that met all of the design requirements. After the best design was chosen, communication with both local and international companies was done to determine the best method for manufacturing. Communication with companies that could give quotes for glue used to prevent the rubber from shearing off the metal surfaces. The part was then ordered and delivered to the university. The part was then assembled to ensure the parts were manufactured properly and will be tested in the future

Altered mechanobiology of Schlemm’s canal endothelial cells in glaucoma

Increased flow resistance is responsible for the elevated intraocular pressure characteristic of glaucoma, but the cause of this resistance increase is not known. We tested the hypothesis that altered biomechanical behavior of Schlemm’s canal (SC) cells contributes to this dysfunction. We used atomic force microscopy, optical magnetic twisting cytometry, and a unique cell perfusion apparatus to examine cultured endothelial cells isolated from the inner wall of SC of healthy and glaucomatous human eyes. Here we establish the existence of a reduced tendency for pore formation in the glaucomatous SC cell—likely accounting for increased outflow resistance—that positively correlates with elevated subcortical cell stiffness, along with an enhanced sensitivity to the mechanical microenvironment including altered expression of several key genes, particularly connective tissue growth factor. Rather than being seen as a simple mechanical barrier to filtration, the endothelium of SC is seen instead as a dynamic material whose response to mechanical strain leads to pore formation and thereby modulates the resistance to aqueous humor outflow. In the glaucomatous eye, this process becomes impaired. Together, these observations support the idea of SC cell stiffness—and its biomechanical effects on pore formation—as a therapeutic target in glaucoma

Globular Cluster UVIT legacy Survey (GlobUleS) III. Omega Centauri in Far-Ultraviolet

We present the first comprehensive study of the most massive globular cluster Omega Centauri in the far-ultraviolet (FUV) extending from the center to ~ 28% of the tidal radius using the Ultraviolet Imaging Telescope aboard AstroSat. A comparison of the FUV-optical color-magnitude diagrams with available canonical models reveals that the horizontal branch (HB) stars bluer than the knee (hHBs) and the white dwarfs (WDs) are fainter in the FUV by ~ 0.5 mag than model predictions. They are also fainter than their counterparts in M13, another massive cluster. We simulated HB with at least five subpopulations, including three He-rich populations with a substantial He enrichment of Y up to 0.43 dex, to reproduce the observed FUV distribution. We find the He-rich younger subpopulations to be radially more segregated than the He-normal older ones, suggesting an in-situ enrichment from older generations. The Omega Cen hHBs span the same effective temperature range as their M13 counterparts, but some have smaller radii and lower luminosities. This may suggest that a fraction of Omega Cen hHBs are less massive than those of M13, similar to the result derived from earlier spectroscopic studies of outer extreme HB stars. The WDs in Omega Cen and M13 have similar luminosity-radius-effective temperature parameters, and 0.44 - 0.46 M$_\odot$ He-core WD model tracks evolving from progenitors with Y = 0.4 dex are found to fit the majority of these. This study provides constraints on the formation models of Omega Cen based on the estimated range in age, [Fe/H] and Y (in particular), for the HB stars.Comment: Accepted for publication in ApJL; 13 pages, 5 figures, 1 tabl

Evidence for Dark Energy from the Cosmic Microwave Background Alone Using the Atacama Cosmology Telescope Lensing Measurements

For the first time, measurements of the cosmic microwave background radiation (CMB) alone favor cosmologies with w = -1 dark energy over models without dark energy at a 3.2-sigma level. We demonstrate this by combining the CMB lensing deflection power spectrum from the Atacama Cosmology Telescope with temperature and polarization power spectra from the "Wilkinson Microwave Anisotropy Probe. The lensing data break the geometric degeneracy of different cosmological models with similar CMB temperature power spectra. Our CMB-only measurement of the dark energy density Omega(delta) confirms other measurements from supernovae, galaxy clusters and baryon acoustic oscillations, and demonstrates the power of CMB lensing as a new cosmological tool