An Efficient Interpolation Technique for Jump Proposals in Reversible-Jump Markov Chain Monte Carlo Calculations

Selection among alternative theoretical models given an observed data set is an important challenge in many areas of physics and astronomy. Reversible-jump Markov chain Monte Carlo (RJMCMC) is an extremely powerful technique for performing Bayesian model selection, but it suffers from a fundamental difficulty: it requires jumps between model parameter spaces, but cannot efficiently explore both parameter spaces at once. Thus, a naive jump between parameter spaces is unlikely to be accepted in the MCMC algorithm and convergence is correspondingly slow. Here we demonstrate an interpolation technique that uses samples from single-model MCMCs to propose inter-model jumps from an approximation to the single-model posterior of the target parameter space. The interpolation technique, based on a kD-tree data structure, is adaptive and efficient in modest dimensionality. We show that our technique leads to improved convergence over naive jumps in an RJMCMC, and compare it to other proposals in the literature to improve the convergence of RJMCMCs. We also demonstrate the use of the same interpolation technique as a way to construct efficient "global" proposal distributions for single-model MCMCs without prior knowledge of the structure of the posterior distribution, and discuss improvements that permit the method to be used in higher-dimensional spaces efficiently.Comment: Minor revision to match published versio

Do Health Care Providers Quality Discriminate? Empirical Evidence from Primary Care Outpatient Clinics

There has been minimal attention paid to the mechanisms of hospital quality oversight that are currently in place. Accordingly this study will analyze the system of hospital quality regulation in the US. The Social Security Act as amended in 1965 gave the Joint Commission on the Accreditation of Healthcare Organizations (JCAHO) "deeming" power for Medicare quality requirements. There are numerous reasons why JCAHO's oversight strategy may be ineffective. The primary reason is the dual role of JCAHO as a regulator and advocate. In conclusion, JCAHO surveys do provide an incentive to hospitals to improve processes of care for the period leading up to an inspection and that incentive gets eliminated after the inspection occurs. JCAHO has announced a change from the scheduled survey to an unannounced strategy. The objective of this change is to provide an incentive to maintain a level of readiness. This may not occur if hospitals are motivated to minimize the overall cost of JCAHO compliance.

Land Grant Application- Stevens, Daniel (Hallowell)

Land grant application submitted to the Maine Land Office on behalf of Daniel Stevens for service in the Revolutionary War, by their widow Jerusha Davenport.https://digitalmaine.com/revolutionary_war_me_land_office/1853/thumbnail.jp

Creatures and environments

I am interested in how things are formed or made both by natural events and by man. The history and story of the environment we inhabit greatly influences my work. I reorganize materials in ways that twist how they may actually develop left to nature. Nature does some very strange and difficult to explain things and I am looking to make the viewer question the boundaries between nature and manmade. My jewelry is similar to a collected specimen, seemingly distant from where it originated but still bearing the evidence of its origin. In this body of work I hope to express my desire to understand the history of the materials that make up my work. When I say the history, it is not the factual origin or processes used to obtain these materials but the fictitious story that I have told to myself. Also, in parallel, I want to explore and try to understand my personal intuition and the need to shape these materials

ISIS Propaganda and United States Countermeasures

The purpose of this study is threefold: 1. Examine the use of propaganda by the Islamic State in Iraq and al Sham (ISIS) and how its propaganda enables ISIS to achieve its objectives; 2. Examine the United States Government (USG) response; 3. Evaluate the effectiveness of the USG response and how it can be improved. The goal of ISIS is to overturn the Middle East, attack westerners in the region and in the West, and create one all-encompassing Islamic State. ISIS\u27 innovative use of propaganda has been central to its success. ISIS uses propaganda more effectively than previous terrorist groups. What is unique about ISIS propaganda is its success at luring disaffected Westerners to its side. The messages of ISIS propaganda are interpreted by studying the teachings of key jihadist theologians and by examining the content of ISIS propaganda. The approach in this thesis is to listen to what ISIS has to say about itself and its objectives. The struggles and short comings of the USG response are attested to by former directors of USG counter terror messaging. This paper reveals the USG\u27s response to ISIS propaganda falls short in effectively addressing the full range of ISIS propaganda\u27s diversity in messages, audiences, and platforms. For the government to effectively undermine the effectiveness of ISIS propaganda, it must accept the need for more creativity and diversity in its messaging, and find a role it can play in conjunction with a supportive private sector capable of engaging in diverse messages to diverse audiences across diverse platforms

Functional Anatomy of the Anconeus: Muscle Architecture and Motor Unit Number Estimation

Exploring muscle architecture in vivo and estimating the number of MUs in the human anconeus muscle have important implications related to the neuromuscular function of this muscle as a model for study in health and disease. The two studies presented in this thesis investigate the functional anatomy of the anconeus in 10 healthy young men (25±3y). Ultrasound imaging has facilitated the measure of the architectural variables, fascicle length (LF) and pennation angle (PA), in many human skeletal muscles in vivo. However, the functional anatomy of the anconeus has been investigated mainly from cadavers exclusively. Thus, the purpose of Chapter 2 was to evaluate, using ultrasonography, the degree of change in architectural features, LF and PA, of the anconeus at rest, across the full range of motion for the elbow joint. The protocol involved imaging the anconeus at 135°, 120°, 90°, 45°, and 0° of elbow flexion. The results indicate that anconeus muscle architecture is dynamic, with LF and PA decreasing and increasing, respectively, with extension of the elbow. The values obtained here are more representative of architectural changes at various elbow joint positions than those reported in cadaveric studies. Motor unit number estimates (MUNE) can be determined electrophysiologically using decomposition-enhanced spike-triggered averaging. To provide the most representative MUNE, muscle activation should equal or exceed the upper limit of MU recruitment to activate the majority of the MU pool. A limitation of muscles studied to date, using DE-STA, is an inability to obtain reliable MUNEs at forces higher than ~30% of a maximum voluntary contraction. Unique features of the anconeus muscle may permit MUNEs at higher muscle activation levels. Thus, the purpose of Chapter 3 was to estimate the number of functional MUs in the anconeus, using DE-STA, at low (10%), moderate (30%), and higher (50%) relative muscle activation levels (root-mean-square of maximum voluntary contraction (RMSMVC)), to determine the effect of muscle activation on MUNEs in this muscle. Low average MUNEs of 58, 38, and 25 were found for the low, moderate, and higher muscle activations, respectively. A histogram of the distribution of surface-detected MU potentials and elbow extensor force-EMG relationship suggest the most representative MUNE was obtained at 50%RMSMVC. The main findings of this thesis are that; 1) anconeus muscle architecture is dynamic, 2) anconeus allows for a more representative MUNE derived at higher muscle activation levels, and 3) the high signal-to-noise ratio that has made the anconeus a choice model in the study of MU properties, is more likely attributed to a relatively low number of MUs than minimal absolute change in its muscle architecture with elbow excursion

Assaying activity and assessing thermostability of hyperthermophilic enzymes

There is now a wide variety of intra- and extra-cellular enzymes available from organisms growing above 75°C, and having sufficient stability to allow assay well above this temperature. For some of these enzymes, to assay below even 95°C will involve measurement below the optimal growth temperature for the organism. The purpose of this chapter is to cover practical aspects of enzyme assay procedures that are specific to high temperatures. Since by far the commonest routine assessment of enzyme stability is activity loss, and because it is always unwise to measure enzyme activity without being confident of its stability during the assay, we include an outline of procedures for measuring enzyme activity loss/stability at high temperatures