PyDEC: Software and Algorithms for Discretization of Exterior Calculus

This paper describes the algorithms, features and implementation of PyDEC, a Python library for computations related to the discretization of exterior calculus. PyDEC facilitates inquiry into both physical problems on manifolds as well as purely topological problems on abstract complexes. We describe efficient algorithms for constructing the operators and objects that arise in discrete exterior calculus, lowest order finite element exterior calculus and in related topological problems. Our algorithms are formulated in terms of high-level matrix operations which extend to arbitrary dimension. As a result, our implementations map well to the facilities of numerical libraries such as NumPy and SciPy. The availability of such libraries makes Python suitable for prototyping numerical methods. We demonstrate how PyDEC is used to solve physical and topological problems through several concise examples.Comment: Revised as per referee reports. Added information on scalability, removed redundant text, emphasized the role of matrix based algorithms, shortened length of pape

Teaching Shakespeare in senior high school.

Thesis (M.A.)--Boston Universit

Official youth soccer club philosophies: experiences of coaches, players, and parents

In the United States, millions of children play soccer for youth soccer clubs. These clubs provide children the opportunity to exercise, compete, enjoy the company of peers, and develop skills. Yet, while many youth soccer clubs have developmental philosophies, the degree to which these philosophies are actually implemented by club coaches is unknown. Since there are many variables involved in the training of a youth soccer player, from coaching philosophies and coaching practices, to athlete\u27s sporting experiences and the climate of the club as a whole, the relationship between these factors is important for anyone involved in creating a youth soccer experience.The purpose of this study was to investigate whether there is congruence between 1) the stated philosophy of the club, 2) implementation of this philosophy by coaches and 3) experiences of players and their parents. Coaches ( n = 3) from a youth soccer club in the Northeast United States, as well as players ( n = 4) and parents (n = 4) from the same club took part in semi-structured interviews to determine the club\u27s implementation of their official club philosophy.Results were determined by content analysis. This analysis resulted in the higher order themes of professional coaching, soccer specific training, and professional organization. Eight lower order themes related to the club\u27s physical environment, atmosphere, administration, style of play, practice characteristics, coaching development, coaching climate, and coach characteristics. These themes were related back to the club\u27s official philosophy. Out of the eight lower-order themes, six were found in the official philosophy. Themes not found in the official philosophy were physical environment and coach characteristics. The club philosophy mentioned the importance of the premier level leagues that the club in a part of. However, no themes relating to the club\u27s status as a member of a select league emerged

Weak values and the Leggett-Garg inequality in solid-state qubits

An implementation of weak values is investigated in solid-state qubits. We demonstrate that a weak value can be non-classical if and only if a Leggett-Garg inequality can also be violated. Generalized weak values are described, where post-selection on a range of weak measurement results. Imposing classical weak values permits the derivation of Leggett-Garg inequalities for bounded operators. Our analysis is presented in terms of kicked quantum nondemolition measurements on a quantum double-dot charge qubit.Comment: 4 pages, 2 figure

Does Transcranial Direct Current Stimulation to the Prefrontal Cortex Affect Social Behavior? A Meta-Analysis

This meta-analysis (k = 48, N = 2196) examined the effect of transcranial direct current brain stimulation (tDCS) applied to the prefrontal cortex on a variety of social behaviors, including aggression, overeating, impulsivity, bias, honesty, and risk-taking. tDCS showed an overall significant effect on reducing undesirable behaviors, with an average effect size of d = −0.20. tDCS was most effective at reducing risk-taking behavior, bias, and overeating. tDCS did not affect aggression, impulsivity, or dishonesty. We examined moderators such as brain region of interest, online vs offline stimulation, within- vs between-subjects designs, dose, and duration, but none showed significant interactions. We also tested for potential publication bias using two different tools, which indicated signs of publication bias in the literature. After correcting for potential publication bias, the effect of tDCS was still significant, but the size was reduced (d = −0.10). These findings suggest the presence of tDCS studies with null findings outside of the published literature. Taken together, these results suggest that although tDCS can reduce undesirable behaviors, researchers should consider the types of behaviors they measure and use strategies to ensure sufficient power to detect a possible effect of tDCS on social behavior

Bell's Theorem and the Causal Arrow of Time

Einstein held that the formalism of Quantum Mechanics (QM) entails "spooky actions at a distance". Indeed, in the 60's Bell showed that the predictions of QM disagree with the results of any locally causal description. Accepting non-local descriptions while retaining causality leads to a clash with the theory of relativity. Furthermore, the causal arrow of time by definition contradicts time-reversal symmetry. For these reasons, some authors (Feynman and Wheeler, Costa de Beauregard, Cramer, Price) have advocated abandoning microscopic causality. In the present article, a simplistic but concrete example of following this line of thought is presented, in the form of a retro-causal toy-model which is stochastic and which provides an appealing description of the specific quantum correlations discussed by Bell. One concludes that Einstein's "spooky actions" may occur "in the past" rather than "at a distance", resolving the tension between QM and relativity, and opening unexplored possibilities for future reformulations of QM.Comment: Extensive changes. Conditionally accepted by American Journal of Physic

Obesity prevention and human service organisations : a survey of managers

The work of human service organisation staff to prevent obesity by assisting disadvantaged families to eat healthily and be active is discussed. The key findings of a study to describe managers' perceptions of the healthy eating and physical activity needs of vulnerable families are highlighted

The Green Horizon: An (Environmental) Hermeneutics of Identification with Nature through Literature

This thesis is an examination of transformative effects of literature on environmental identity. The work begins by examining and expanding the Deep Ecology concept of identification-with-nature. The potential problems with identification through direct encounters are used to argue for the relevance of the possibility of identification-through-literature. Identification-through-literature is then argued for using the hermeneutic and narrative theories of Hans-Georg Gadamer and Paul Ricoeur, as well as various examples of nature writing and fiction

Partial gravity habitat study: With application to lunar base design

Comprehensive design requirements associated with designing habitats for humans in a partial gravity environment were investigated and then applied to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable gravity research facilities, or a rotating spacecraft. Design requirements for partial gravity environments include: (1) locomotion changes in less than normal Earth gravity; (2) facility design issues, such as interior configuration, module diameter and geometry; and (3) volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a Lunar Base, it was necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress. Radiation protection issues were addressed to provide a safe and healthy environment for the crew, and finally, the overall site was studied to locate all associated facilities in context with the habitat. Mission planning was not the purpose of this study; therefore, a Lockheed scenario was used as an outline for the Lunar Base application, which was then modified to meet the project needs