Bayesian Learning and Predictability in a Stochastic Nonlinear Dynamical Model

Bayesian inference methods are applied within a Bayesian hierarchical modelling framework to the problems of joint state and parameter estimation, and of state forecasting. We explore and demonstrate the ideas in the context of a simple nonlinear marine biogeochemical model. A novel approach is proposed to the formulation of the stochastic process model, in which ecophysiological properties of plankton communities are represented by autoregressive stochastic processes. This approach captures the effects of changes in plankton communities over time, and it allows the incorporation of literature metadata on individual species into prior distributions for process model parameters. The approach is applied to a case study at Ocean Station Papa, using Particle Markov chain Monte Carlo computational techniques. The results suggest that, by drawing on objective prior information, it is possible to extract useful information about model state and a subset of parameters, and even to make useful long-term forecasts, based on sparse and noisy observations

Simulation at Dryden Flight Research Facility from 1957 to 1982

The Dryden Flight Research Facility has been a leader in developing simulation as an integral part of flight test research. The history of that effort is reviewed, starting in 1957 and continuing to the present time. The contributions of the major program activities conducted at Dryden during this 25-year period to the development of a simulation philosophy and capability is explained

I Like Your Apron And Your Bonnet And Your Little Quaker Gown

https://digitalcommons.library.umaine.edu/mmb-vp/1568/thumbnail.jp

An Empirical Examination of Symptom Substitution Associated with Behavior Therapy for Tourette\u27s Disorder

Over the past six decades, behavior therapy has been a major contributor to the development of evidence-based psychotherapy treatments. However, a long-standing concern with behavior therapy among many nonbehavioral clinicians has been the potential risk for symptom substitution. Few studies have been conducted to evaluate symptom substitution in response to behavioral treatments, largely due to measurement and definitional challenges associated with treated psychiatric symptoms. Given the overt motor and vocal tics associated with Tourette’s disorder, it presents an excellent opportunity to empirically evaluate the potential risk for symptom substitution associated with behavior therapy. The present study examined the possible presence of symptom substitution using four methods: (a) the onset of new tic symptoms, (b) the occurrence of adverse events, (c) change in tic medications, and (d) worsening of co-occurring psychiatric symptoms. Two hundred twenty-eight participants with Tourette’s disorder or persistent motor or vocal tic disorders were randomly assigned to receive behavioral therapy or supportive therapy for tics. Both therapies consisted of eight sessions over 10 weeks. Results indicated that participants treated with behavior therapy were not more likely to have an onset of new tic symptoms, experience adverse events, increase tic medications, or have an exacerbation in co-occurring psychiatric symptoms relative to participants treated with supportive therapy. Further analysis suggested that the emergence of new tics was attributed with the normal waxing and waning nature of Tourette’s disorder. Findings provide empirical support to counter the long-standing concern of symptom substitution in response to behavior therapy for individuals with Tourette\u27s disorder

Red-tide–associated Mass Mortality in 2005 of the Sand Dollars Encope aberrans, Encope michelini, and Mellita tenuis (Echinodermata: Echinoidea) on the Central Florida Gulf Coast Shelf

In March 2005, populations of Encope aberrans and E. michelini found at 20-m depth (ca. 27 km west of Captiva Island) and of Mellita tenuis at 6.5-m depth (ca. 7 km west of Egmont Key) were studied to calculate density and size frequency distribution. All individuals were alive. A red tide occurred on the central Florida Gulf Coast shelf during the summer. In Sept., all individuals in these populations were dead. Dead individuals had lost their spines and were gray but intact, indicating recent death. On the same date, all E. michelini and E. aberrans were alive in a population at 20-m depth (ca. 26 km north of the site off Captiva Island and ca. 23 km west of Gasparilla Island). All individuals in a population of M. tenuis at 2-m depth immediately offshore Fort De Soto Park were alive 1 mo after the observation of complete mortality off Egmont Key. All E. aberrans at a site 28 km southwest of Egmont Key were dead in Oct. In May 2006, live E. michelini occurred at the Captiva site at the same density as in March and Sept. 2005. Their large size indicates their origin was by migration from nearby areas unaffected by the red tide

Stormwater Research Roadmap for Minnesota

The goal of the Stormwater Research Roadmap is to articulate major research needs to improve stormwater management in Minnesota. Multiple sources and approaches were used to identify stormwater research needs for Minnesota, including a review of relevant stormwater-related documents, and state-wide survey of stormwater managers, focus groups, and policy actor interviews. The Stormwater Research Roadmap for Minnesota identifies eight major areas that need additional research to improve stormwater management for communities, professionals, and agencies. Specific examples are included for each. Research in these areas can lead to more innovative management techniques and increased effectiveness and efficiency to prevent, minimize, and mitigate the effects of runoff from the built environment. The Roadmap also presents criteria to rank research needs. Data for the Roadmap was collected from 2017-2018 and was published in 2018.his work was supported with funds from the Minnesota Clean Water, Land, and Legacy Amendment allocated by the Minnesota Legislature through the Minnesota Pollution Control Agency

Undernutrition and stage of gestation influence fetal adipose tissue gene expression

Funded by the Scottish Government’s Rural and Environment Science and Analytical Services Division (RESAS), including the Strategic Partnership for Animal Science Excellence (SPASE) and the U.S. National Institutes of Health (HD045784). None of the authors had any financial or personal conflicts of interest.Peer reviewedPostprin

Searching for Machos (and other Dark Matter Candidates) in a Simulated Galaxy

We conduct gravitational microlensing experiments in a galaxy taken from a cosmological N-body simulation. Hypothetical observers measure the optical depth and event rate toward hypothetical LMCs and compare their results with model predictions. Since we control the accuracy and sophistication of the model, we can determine how good it has to be for statistical errors to dominate over systematic ones. Several thousand independent microlensing experiments are performed. When the ``best-fit'' triaxial model for the mass distribution of the halo is used, the agreement between the measured and predicted optical depths is quite good: by and large the discrepancies are consistent with statistical fluctuations. If, on the other hand, a spherical model is used, systematic errors dominate. Even with our ``best-fit'' model, there are a few rare experiments where the deviation between the measured and predicted optical depths cannot be understood in terms of statistical fluctuations. In these experiments there is typically a clump of particles crossing the line of sight to the hypothetical LMC. These clumps can be either gravitationally bound systems or transient phenomena in a galaxy that is still undergoing phase mixing. Substructure of this type, if present in the Galactic distribution of Machos, can lead to large systematic errors in the analysis of microlensing experiments. We also describe how hypothetical WIMP and axion detection experiments might be conducted in a simulated N-body galaxy.Comment: 18 pages of text (LaTeX, AASTeX) with 12 figures. submitted to the Astrophysical Journa