Programs as Polypeptides

We describe a visual programming language for defining behaviors manifested by reified actors in a 2D virtual world that can be compiled into programs comprised of sequences of combinators that are themselves reified as actors. This makes it possible to build programs that build programs from components of a few fixed types delivered by diffusion using processes that resemble chemistry as much as computation.Comment: in European Conference on Artificial Life (ECAL '15), York, UK, 201

Low cost radar and sonar using Open Source hardware and software

Includes abstract.Includes bibliographical references (leaves 89-91).The full range of radar types and innovations can be complex and difficult to prototype, especially for institutions that wish to perform a wide range of experiments for low financial cost. Radar and sonar system development can benefit from digital technology that is powerful for research purposes, easy to use, and inexpensive. The purpose of this thesis was the development of a sonar application using the Universal Software Radio Peripheral and the GNU Radio software framework. These are Open Source tools created for the software-defined radio community. These tools provide a powerful yet flexible means to experiment with a wide range of radio frequency applications, using a minimal amount of relatively cheap hardware. In this thesis, these tools were modified from their original telecommunications purpose, to produce a sonar system that could eventually be scaled to a prototype radar system using the same device and software framework

Circadian Control of Neuroendocrine Circuits Regulating Female Reproductive Function

Female reproduction requires the precise temporal organization of interacting, estradiol-sensitive neural circuits that converge to optimally drive hypothalamo-pituitary–gonadal (HPG) axis functioning. In mammals, the master circadian pacemaker in the suprachiasmatic nucleus (SCN) of the anterior hypothalamus coordinates reproductively relevant neuroendocrine events necessary to maximize reproductive success. Likewise, in species where periods of fertility are brief, circadian oversight of reproductive function ensures that estradiol-dependent increases in sexual motivation coincide with ovulation. Across species, including humans, disruptions to circadian timing (e.g., through rotating shift work, night shift work, poor sleep hygiene) lead to pronounced deficits in ovulation and fecundity. Despite the well-established roles for the circadian system in female reproductive functioning, the specific neural circuits and neurochemical mediators underlying these interactions are not fully understood. Most work to date has focused on the direct and indirect communication from the SCN to the gonadotropin-releasing hormone (GnRH) system in control of the preovulatory luteinizing hormone (LH) surge. However, the same clock genes underlying circadian rhythms at the cellular level in SCN cells are also common to target cell populations of the SCN, including the GnRH neuronal network. Exploring the means by which the master clock synergizes with subordinate clocks in GnRH cells and its upstream modulatory systems represents an exciting opportunity to further understand the role of endogenous timing systems in female reproduction. Herein we provide an overview of the state of knowledge regarding interactions between the circadian timing system and estradiol-sensitive neural circuits driving GnRH secretion and the preovulatory LH surge

Do Jet Fuel Price Movements Help Forecast Airline Fares and the Demand for Air Travel?

Citation: Bebonchu, A., Bachmeier, L., & Williams C. (2018) Do Jet Fuel Price Movements Help Forecast Airline Fares and the Demand for Air Travel? Unpublished manuscript.The paper studies the predictive content of jet fuel prices for the U.S. aviation industry through in-sample and out-of-sample forecasting exercises. Our results suggest the possibility of limited improvements in the predictions of airline fares, and little evidence of predictability from jet fuel prices to measures of air travel demand

Population Viability Analysis for the Leopard Darter(Percidae: Percina pantherina)

Chapter II of this thesis is in the format for publication in the journal Conservation Biology. The work was funded by the United States National Biological Service and the Oklahoma cooperative Fish and wildlife Research Unit

Current practices in cancer spatial data analysis: a call for guidance

There has long been a recognition that place matters in health, from recognition of clusters of yellow fever and cholera in the 1800s to modern day analyses of regional and neighborhood effects on cancer patterns. Here we provide a summary of discussions about current practices in the spatial analysis of georeferenced cancer data by a panel of experts recently convened at the National Cancer Institute