A cross-cultural study of suicide in twenty-three pre-literate societies

Thesis (M.S.)--Boston Universit

Stable Unitary Integrators for the Numerical Implementation of Continuous Unitary Transformations

The technique of continuous unitary transformations has recently been used to provide physical insight into a diverse array of quantum mechanical systems. However, the question of how to best numerically implement the flow equations has received little attention. The most immediately apparent approach, using standard Runge-Kutta numerical integration algorithms, suffers from both severe inefficiency due to stiffness and the loss of unitarity. After reviewing the formalism of continuous unitary transformations and Wegner's original choice for the infinitesimal generator of the flow, we present a number of approaches to resolving these issues including a choice of generator which induces what we call the "uniform tangent decay flow" and three numerical integrators specifically designed to perform continuous unitary transformations efficiently while preserving the unitarity of flow. We conclude by applying one of the flow algorithms to a simple calculation that visually demonstrates the many-body localization transition.Comment: 13 pages, 4 figures, Comments welcom

Automated precision passing system

Athletes are always seeking ways to improve their performance. Down time and a lack of capable throwers prevent athletic receivers from practicing their skills. We hope to aid athletes in receiving drills within their respective sports and increase practice efficiency. In order to achieve this, the machine has one major axis of rotation driven by a motor. This enables it to adjust where the ball is being thrown. Using an Arduino Uno coupled with a Roboteq AX1500 motor driver, the Automated Precision Passing System is able to throw a ball to a specified point in space by adjusting both the azimuth and ball-throwing motor speed. Our testing shows that our prototype has the ability to position itself in three different orientations as well as adjust the launch motor speed, but we were unable to launch the ball the original distance that we desired. From this project, we gained valuable knowledge in the areas of machine design, control systems, and project management. In order to continue the project and create a functional consumer product there are several improvements that need to be made to the system. The Automated Precision Passing System needs to be more rigid, have more power, and include more throwing positions

Multiple-scale structures: from Faraday waves to soft-matter quasicrystals

For many years, quasicrystals were observed only as solid-state metallic alloys, yet current research is now actively exploring their formation in a variety of soft materials, including systems of macromolecules, nanoparticles and colloids. Much effort is being invested in understanding the thermodynamic properties of these soft-matter quasicrystals in order to predict and possibly control the structures that form, and hopefully to shed light on the broader yet unresolved general questions of quasicrystal formation and stability. Moreover, the ability to control the self-assembly of soft quasicrystals may contribute to the development of novel photonic or other applications based on self-assembled metamaterials. Here a path is followed, leading to quantitative stability predictions, that starts with a model developed two decades ago to treat the formation of multiple-scale quasiperiodic Faraday waves (standing wave patterns in vibrated fluid surfaces) and which was later mapped onto systems of soft particles, interacting via multiple-scale pair potentials. The article reviews, and substantially expands, the quantitative predictions of these models, while correcting a few discrepancies in earlier calculations, and presents new analytical methods for treating the models. In so doing, a number of new stable quasicrystalline structures with octagonal, octadecagonal and higher-order symmetries, some of which may, it is hoped, be observed in future experiments.Comment: 22 pages, 22 figures, 1 table. Comments welcom

Using Professionally Trained Interpreters to Increase Patient/Provider Satisfaction: Does It Work?

Examines the need for trained medical interpreters by comparing the satisfaction of emergency room patients, doctors, and triage and discharge nurses when provided with interpreters and when provided only with telephone language lines or ad hoc services

The Key To Solving Agency Lock-In: Prepublication Regulatory Discussions (Pre Reg)

Most legally binding administrative rules emerge from the notice-and-comment process, which explicitly requires the agency to consider input from the general public. However, by the time the opportunity for public input occurs, the agency is already substantially locked into its chosen approach and cannot act on new information in the comments. This is true even though its chosen approach was decided upon with input from only those the agency routinely deals with. This process entrenches already established interests and prevents those without existing agency connections from meaningfully contributing earlier in the process. This problem could be solved by holding public discussions online before the publication of the proposed rule and therefore before the agency is locked in. Employing modem Internet guidelines would ensure that all those who wish to participate can, while preventing bad actors from disrupting the purpose and atmosphere of the discussion. This approach would combine the benefits of current alternative agency practices while avoiding the drawbacks that frequently prevent their use. Agencies that are expected to work on behalf of the public should likewise have an effective method to accept input from that same public before becoming locked into a choice of action

Administrative Compensation for Military Harassment and Sexual Assault: A Win-Win for Victims and the Military

Last year, none of the more than 20,000 victims of sexual assault in the military were entitled to any compensation. Nor were the hundreds of thousands of service members subjected to racial and sexual harassment compensated in any way. Advocates have fought for decades to overturn the Feres doctrine to allow victims to sue the government in court. The military has countered that it must retain control over all issues involving discipline. However, the military lacks the information necessary to be able to take effective action against those who harm others because many victims are afraid to come forward for fear of retaliation. This Article offers a way to solve both problems. It proposes creating an administrative process to compensate victims for the harm they endured while simultaneously providing an incentive for them to report the initial crime, as well as any retaliation they experience, thereby finally providing the military with the critical information it needs to act, which it is unable to obtain any other way

Rethinking Retroactive Rulemaking: Solving the Problem of Adjudicative Deference

The Chevron doctrine enables courts to defer to authoritative, legally binding agency interpretations of ambiguous statutes. Though more frequently applied when reviewing rulemaking, the doctrine is actually more powerful when applied to an adjudication. In an adjudication, the agency can attach consequences to past actions made before the interpretation announced in the adjudication itself. Since such a determination will receive deference on review, this declaration effectively becomes a new rule, having gone through neither public notice or public comment. Not only does it become a new rule, it becomes a new rule that is effective retroactively. It is illogical to have a system that gives more power to a less democratic process, and Chevron deference should therefore not apply to adjudication.The notice and comment process that Chevron more typically defers to is the best method yet devised to enable an agency to benefit from not only its own expertise but that of the general interested public as well. Public comment can point out potential problems with the agency’s preferred approach that the agency has not otherwise foreseen as well as present solutions not yet considered by the agency. This type of input could be beneficial for ambiguities that come to light in an adjudication as well as those initially addressed in rulemaking. Agencies should therefore be encouraged to undertake rulemakings when ambiguities arise in adjudications. But because of the retroactive nature of adjudication itself, these rules would need to (at least potentially) be used retroactively in the adjudication that gave rise to them, or there would be no incentive for the agency to undertake the delay and effort of the rulemaking. This Article argues that not only should adjudications not receive Chevron deference, but a limited exception should also be created to the current ban on retroactive rulemaking to encourage agencies to engage in the rulemaking process to address ambiguities arising in adjudication. This exception could be specifically cabined to apply only in these unique situations. Enabling such an exception would provide the agency and the public with the benefits arising from public participation