Characterization and Oxidation Behavior of Rayon-Derived Carbon Fibers

Rayon-derived fibers are the central constituent of reinforced carbon/ carbon (RCC) composites. Optical, scanning electron, and transmission electron microscopy were used to characterize the as-fabricated fibers and the fibers after oxidation. Oxidation rates were measured with weight loss techniques in air and oxygen. The as-received fibers are approximately 10 micron in diameter and characterized by grooves or crenulations around the edges. Below 800 C, in the reaction-controlled region, preferential attack began in the crenulations and appeared to occur down fissures in the fibers

Sprout: A Little Footprint with a Big Impact

This Innovation Portfolio is designed to walk the reader through the essential steps our team took to address the issue of the under-utilization of the Meijer Holland Campus in the fall of 2016. As a satellite campus of Grand Valley State University, the Meijer Holland Campus seeks to engage its local community in a more sustained and in-depth way. This brief begins by introducing the reader to the historical and situational context of the Holland campus, followed by a map displaying the stakeholders involved. Through talking with a number of those stakeholders, we gained valuable insights that were grouped together to reveal key themes which were then leveraged in the process of generating our top five innovations. At the final symposium presentation, we delivered our final innovation: Sprout, a Sustainability and Agriculture Bastion. Collaborator debriefs, interviews and secondary research are also included here and were all additional stepping stones that assisted us in our innovation process

Manifest Electromagnetic Duality in Closed Superstring Field Theory

The free action for massless Ramond-Ramond fields is derived from closed superstring field theory using the techniques of Siegel and Zwiebach. For the uncompactified Type IIB superstring, this gives a manifestly Lorentz-covariant action for a self-dual five-form field strength. Upon compactification to four dimensions, the action depends on a U(1) field strength from 4D N=2 supergravity. However, unlike the standard Maxwell action, this action is manifestly invariant under the electromagnetic duality transformation which rotates $F_{mn}$ into $\epsilon_{mnpq} F^{pq}$.Comment: Added three references and corrected one footnote. 15 pages harvma

Relationships between digit ratio (2D:4D) and basketball performance in Australian men

Objective To investigate relationships between the digit ratio (2D:4D) and competitive basketball performance in Australian men. Methods Using an observational cross‐sectional design a total of 221 Australian basketball players who competed in the Olympic Games, International Basketball Federation World Championships/Cup, Australian National Basketball League, Central Australian Basketball League or socially had their 2D:4Ds measured. Analysis of variance was used to assess differences in mean 2D:4Ds between men playing at different competitive standards, with relationships between 2D:4Ds and basketball game‐related statistics assessed using Pearson\u27s product moment correlations in men playing at a single competitive standard. Results There were significant differences between competitive standards for the left 2D:4D following Bonferroni correction, but not for the right 2D:4D, with basketballers who achieved higher competitive standards tending to have lower left 2D:4Ds. No important correlations between 2D:4D and basketball game‐related statistics were found, with correlations typically negligible. Conclusions This study indicated that the 2D:4D can discriminate between basketballers competing at different standards, but not between basketballers within a single competitive standard using objective game‐related statistics

Superspace Effective Actions for 4D Compactifications of Heterotic and Type II Superstrings

Two-dimensional sigma models are defined for the new manifestly spacetime supersymmetric description of four-dimensional compactified superstrings. The resulting target-superspace effective action is constrained by the way the spacetime dilaton couples to the worldsheet curvature: For the heterotic superstring, the worldsheet curvature couples to the real part of a chiral multiplet, and for Type II it couples to the real part of the sum of a vector multiplet and a tensor hypermultiplet. For the Type II superstring, this contradicts the standard folklore that only a hypermultiplet counts string-loops, explains the peculiar dilaton coupling of Ramond-Ramond fields, and allows the effective action to be easily written in N=2 4D superspace. It also implies that vector multiplet interactions get no quantum corrections, while hypermultiplet interactions can only get corrections if mirror symmetry is non-perturbatively broken.Comment: 45 p. (Replaced sentence on non-local terms and added 2 references

Off-shell Supersymmetry versus Hermiticity in the Superstring

We point out that off-shell four-dimensional supersymmetry implies strange hermiticity properties for the N=1 RNS superstring. However, these hermiticity properties become natural when the N=1 superstring is embedded into an N=2 superstring.Comment: 4 pages harvma

Ten-Dimensional Supergravity Constraints from the Pure Spinor Formalism for the Superstring

It has recently been shown that the ten-dimensional superstring can be quantized using the BRST operator $Q=\oint\lambda^\alpha d_\alpha$ where $\lambda^\alpha$ is a pure spinor satisfying $\lambda \gamma^m \lambda=0$ and $d_\alpha$ is the fermionic supersymmetric derivative. In this paper, the pure spinor version of superstring theory is formulated in a curved supergravity background and it is shown that nilpotency and holomorphicity of the pure spinor BRST operator imply the on-shell superspace constraints of the supergravity background. This is shown to lowest order in $\alpha'$ for the heterotic and Type II superstrings, thus providing a compact pure spinor version of the ten-dimensional superspace constraints for N=1, Type IIA and Type IIB supergravities. Since quantization is straightforward using the pure spinor version of the superstring, it is expected that these methods can also be used to compute higher-order $\alpha'$ corrections to the ten-dimensional superspace constraints.Comment: 30 pages late

The Great Escape: The Role of Self-esteem and Self-related Cognition in Terror Management

Integrating terror management theory and objective self-awareness theory, we propose the existential escape hypothesis, which states that people with low self-esteem should be especially prone to escaping self-awareness as a distal response to thoughts of death. This is because they lack the means to bolster the self as a defense, and the propensity to bolster the self reduces the motivation to escape from self-awareness. Five studies supported this hypothesis. Individuals low, but not high, in self-esteem scored lower on a measure of private self-awareness (Study 1), showed less implicit self-activation (Studies 2 & 3), were more likely to choose to write about others than themselves (Study 4), and consumed more alcohol in a field study at a nightclub (Study 5) in response to mortality reminders. Implications for terror management theory (highlighting an additional route to defend against mortality awareness), self-regulation, physical health and well-being are discussed