A Statistical Analysis of RNA Folding Algorithms Through Thermodynamic Parameter Perturbation

Computational RNA secondary structure prediction is rather well established. However, such prediction algorithms always depend on a large number of experimentally measured parameters. Here, we study how sensitive structure prediction algorithms are to changes in these parameters. We find that already for changes corresponding to the actual experimental error to which these parameters have been determined 30% of the structure are falsly predicted and the ground state structure is preserved under parameter perturbation in only 5% of all cases. We establish that base pairing probabilities calculated in a thermal ensemble are a viable though not perfect measure for the reliability of the prediction of individual structure elements. A new measure of stability using parameter perturbation is proposed, and its limitations discussed.Comment: 6 pages, 3 figures, 1 table submitted to Nucleic Acids Researc

Testing the Power of Leading Indicators to Predict Business Cycle Phase Changes

In the business cycle literature researchers often want to determine the extent to which models of the business cycle reproduce broad characteristics of the real world business cycle they purport to represent. Of considerable interest is whether a model’s implied cycle chronology is consistent with the actual business cycle chronology. In the US, a very widely accepted business cycle chronology is that compiled by the National Bureau of Economic research (NBER) and the vast majority of US business cycle scholars have, for many years, proceeded to test their models for their consistency with the NBER dates. In doing this, one of the most prevalent metrics in use since its introduction into the business cycle literature by Diebold and Rudebusch (1989) is the so-called quadratic probability score, or QPS. However, an important limitation to the use of the QPS statistic is that its sampling distribution is unknown so that rigorous statistical inference is not feasible. We suggest circumventing this by bootstrapping the distribution. This analysis yields some interesting insights into the relationship between statistical measures of goodness of fit of a model and the ability of the model to predict some underlying set of regimes of interest. Furthermore, in modeling the business cycle, a popular approach in recent years has been to use some variant of the so-called Markov regime switching (MRS) model first introduced by Hamilton (1989) and we therefore use MRS models as the framework for the paper. Of course, the approach could be applied to any US business cycle model.Markov Regime Switching, Business Cycle, Quadratic Probability Score

DURATION DEPENDENCE IN THE US BUSINESS CYCLE

Durland and McCurdy (1994) investigated the issue of duration dependence in US business cycle phases using a Markov regime switching approach, introduced by Hamilton (1989) and extended to the case of variable transition parameters by Filardo (1994). In Durland and McCurdy’s model duration alone was used as an explanatory of the transition probabilities. They found that recessions were duration dependent whilst expansions were not. In this paper, we explicitly incorporate the widely-accepted US business cycle phase change dates as determined by the NBER, and use a state-dependent multinomial Logit (and Probit) modelling framework. The model incorporates both duration and movements in two leading indexes - one designed to have a short lead (SLI) and the other designed to have a longer lead (LLI) - as potential explanators. We find that doing so suggests that current duration is not only a significant determinant of transition out of recessions, but that there is some evidence that it is also weakly significant in the case of expansions. Furthermore, we find that SLI has more informational content for the termination of recessions whilst LLI does so for expansions.

New concept in brazing metallic honeycomb panels

Aluminum oxide coating provides surface which will not be wetted by brazing alloy and which stops metallic diffusion welding of tooling materials to part being produced. This method eliminates loss of tooling materials and parts from braze wetting and allows fall-apart disassembly of tooling after brazing

Evaluation of a Rheumatology Patient Prioritization Triage System

The United States health care system is currently experiencing an increase in demand for services due to an aging population. Rheumatology, an Internal Medicine sub-specialty, treats those patients with arthritic conditions as well as other autoimmune and inflammatory conditions. A shortage of rheumatologists is projected by 2025, adding additional stress to an already burdened clinical area.This means patients can face substantial wait times when requesting consultation with a rheumatology provider.This capstone project will present three manuscripts that explore the referral process from primary to specialty care and strategies to reduce wait times. The first manuscript is a literature review that presents information surrounding current referral processes.The second manuscript presents current evidence-based practice guidelines on the identification and management of rheumatoid arthritis (RA) in primary care. Finally, the third manuscript evaluates a rheumatology patient prioritization triage system currently being used in a large rheumatology clinic in central Kentucky to determine its accuracy in identifying acutely ill patients. The combined information presented in these manuscripts help support recommendations for improving the referral process between primary and specialty providers to ensure that patients receive necessary care delivered in a timely manner to optimize patient experience and outcomes

Wild things in the north? Hunter-gatherers and the tyranny of the colonial perspective

The paper argues for a synthesis of Darwinian and Marxist theories of evolution. We challenge claims that hunter-gatherer societies evolve via a natural progression from simple to complex, arguing instead that huntergatherer social strategies are adaptations to specifiable ecological conditions, while having emergent consequences that shape the political structure of hunter-gatherer society. We review the various theories of which we make use, and those that we challenge, and test them against data from the ethnographic and archaeological literature on hunter-gatherers, discussing the evidence for variation in technology, mobility, territoriality and egalitarianism versus social inequality. We conclude that human societies do not evolve via a natural progression from simple to complex forms, and that complex hunter-gatherers are not necessarily incipient farmers. Many of the assumptions that colour common views of the development of hunter-gatherer complexity and the appearance of agriculture in prehistoric Europe have their roots, consciously or unconsciously, in nineteenth-century European colonialism

Archaeology and art

Archaeologists have approached the study of art from several directions, drawing their inspiration variously from evolutionary biology, anthropology, and art history.We examine the strengths and weaknesses of each of these approaches and demonstrate the unique opportunities open to archaeology in the study of art, from its origins to the recent past

A Method for Determining Offtracking of Multiple Unit Vehicle Combinations

The required road width around curves on forest roads is largely determined by the difference in wheel paths between the inside front tractor wheel and the inside rear trailer wheel. This difference, known as offtracking, is a function of the vehicle and road geometry. This paper presents a method for determining the offtracking of fixed and variable length multiple unit vehicle combinations travelling over forest roads. The computational method numerically integrates the differential equations which compute the path (tractrix) that the rear of a vehicle follows from a given steering curve. A unique three-point solution method is used to determine the instantaneous center of rotation for trailers in the vehicle combination. The method is shown to have good agreement with experimental data. It is suitable for use on microcomputers for single and multiple curves. A microcomputer program, OFFTRACK, was developed using this methodology

Performance-based standards for juvenile corrections

Total quality management (TQM) has revolutionized business, and some of its components can be applied to corrections. The importance of information for developing performance-based standards is obvious. Much more difficult is the process of deciding what information to obtain and how to use it. In the area of juvenile corrections, information about the conditions or environments of juvenile facilities and how these conditions are associated with intermediate and longterm outcomes will be invaluable in developing performance-based standards