Showing 5331 - 5340 of 5709 Items
The Current Support Theorem in Context
Date: 2023-01-01
Creator: Ethan Winters
Access: Open access
- This work builds up the theory surrounding a recent result of Erlandsson, Leininger, and Sadanand: the Current Support Theorem. This theorem states precisely when a hyperbolic cone metric on a surface is determined by the support of its Liouville current. To provide background for this theorem, we will cover hyperbolic geometry and hyperbolic surfaces more generally, cone surfaces, covering spaces of surfaces, the notion of an orbifold, and geodesic currents. A corollary to this theorem found in the original paper is discussed which asserts that a surface with more than $32(g-1)$ cone points must be rigid. We extend this result to the case that there are more than $3(g-1)$ cone points. An infinite family of cone surfaces which are not rigid and which have precisely $3(g-1)$ cone points is also provided, hence demonstrating tightness.
Bowdoin College Catalogue (1953-1954)
Date: 1954-01-01
Access: Open access
- Bowdoin College Bulletin no. 311
Mutual benefits of inducible defenses to crab predators in the blue mussel Mytilus edulis in a multi-predator environment
Date: 2021-01-01
Creator: Sophia Walton
Access: Open access
- The blue mussel Mytilus edulis alters its phenotype in species-specific ways in response to either green crab (Carcinus maenus) or sea star (Asterias sp.) predation. Previous studies have shown that only sea stars induce changes in abductor muscle morphology, while green crabs generally alter the shape and thickness of shells. In the Western Gulf of Maine, Blue mussels collected from wave protected sites with abundant green crab predators were shown to have significantly thicker shells and larger adductor muscles than mussels collected from wave exposed sites with few green crab predators. The phenotypes of mussels originating from wave-protected and high green crab abundance sites increased the handling time by A. forbesi compared to sites with low wave exposure and high green crab abundance. These results contradict the paradigm that shell thickness trades off with abductor morphology, and I propose that a likely candidate for increased energy allocation to these traits is a decrease in reproductive allocation. My results further suggest that the escalating “arms race” between invasive green crabs and blue mussels in the Western Gulf of Maine is leading to changes in the phenotypic response of mussel populations in ways that are likely impacting sea star foraging dynamics.
Measurement of the tau lepton electronic branching fraction
Date: 1992-01-01
Creator: D. S. Akerib, B. Barish, M. Chadha, D. F. Cowen, G., Eigen, J. S. Miller, J. Urheim, A. J. Weinstein, D. Acosta, G. Masek, B. Ong, H. Paar, M. Sivertz, A. Bean, J. Gronberg, R. Kutschke, S. Menary, R. J. Morrison, H. N. Nelson, J. D. Richman, H. Tajima, D. Schmidt, D. Sperka, M. S. Witherell, M. Procario, S. Yang, M. Daoudi, W. T. Ford, D. R. Johnson, K. Lingel, M. Lohner
Access: Open access
- The tau lepton electron branching fraction has been measured with the CLEO II detector at the Cornell Electron Storage Ring as Be=0.17490.00140.0022, with the first error statistical and the second systematic. The measurement involves counting electron-positron annihilation events in which both taus decay to electrons, and normalizing to the number of tau-pair decays expected from the measured luminosity. Detected photons in these events constitute a definitive observation of tau decay radiation. © 1992 The American Physical Society.
Promoter Choice in Transvection at the eya Gene of Drosophila melanogaster This record is embargoed.
- Embargo End Date: 2027-05-15
Date: 2024-01-01
Creator: Victoria Dunphy
Access: Embargoed
Bondi Accretion in Trumpet Geometries
Date: 2016-01-01
Creator: August J Miller
Access: Open access
- The Bondi solution, which describes the radial inflow of a gas onto a non-rotating black hole, provides a powerful test for numerical relativistic codes. However, this solution is typically derived in Schwarzschild coordinates, which are not well suited for dynamical spacetime evolutions. Instead, many current numerical relativistic codes adopt moving-puncture coordinates, which render black holes in trumpet geometries. Here we transform the Bondi solution into two different trumpet coordinate systems, both of which result in regular expressions for the fluid flow extending into the black hole interior. We also evolve these solutions numerically and demonstrate their usefulness for testing and calibrating numerical codes.
Young Authoritarians? Trends and Individual Differences in Preschoolers' Perceptions of Adult Authority
Date: 2018-05-01
Creator: Ava Alexander
Access: Open access
- Although traditional stage theories (e.g., Piaget, 1965) postulate that preschool age children are guided entirely by punishment avoidance and absolute deference to authority, more recent research suggests that their concepts of adult authority are complex and vary based on social cognitive domain and the content of the commands (e.g., Tisak, 1986). Also, although past studies have shown that the majority of children will reject adult authority in certain contexts, much individual variation between children has been observed (e.g., Laupa, 1994). The current study expanded upon past research by exposing children to multiple typical and atypical commands across domains, while also testing for individual differences based on two forms of parental authoritarianism. Results showed that children as young as four reject commands that go against established moral or conventional norms, and sometimes reject commands in the personal domain. This pattern grew stronger with age. High right-wing authoritarianism was a significant predictor of more authoritarian parenting style, and also predicted lower child support for authority in typical conventional scenarios.