A flume experiment on the effect of constriction shape on the formation of forced pools

A series of 18 flume runs were conducted in a 6-m long, 0.5-m wide recirculating flume with a bed gradient of 0.8% to determine the influence of obstruction shape on the formation and characteristics of forced pools. Six different-shaped obstructions were added to the flume with the maximum width of the obstruction held constant at 20 cm, which equaled a 40% constriction of flow. The obstruction shapes used included a square, a rectangle, a right triangle with the hypotenuse-facing upstream, a right triangle with the hypotenuse-facing downstream, a combination of a square and triangle with the hypotenuse-facing upstream, and a rectangle and semi-circle shape. Three flume runs were conducted with each obstruction shape. A profile of the flume bed was taken after each experiment and a grid measurement of bed elevations for the last run were conducted to create topographic maps of the flume bed to compare pool-riffle morphologies. ANOVA results indicate pool depth, pool location, and the distance between the pool center and the riffle crest all vary with the obstruction shape. Obstructions with a more blunt upstream face created deeper pools, more total scour and longer pool-riffle sequence lengths than pools formed by obstructions with a more gradual narrowing of flow. The increased volume of scour associated with obstructions that rapidly narrow flow also creates larger volume riffles that cover a greater extent of the channel bed

The Analysis of Pixel Intensity (Myocardial Signal Density) Data: The Quantification of Myocardial Perfusion by Imaging Methods.

This paper described a number of important issues in the analysis of pixel intensity data, as well as approaches for dealing with these. We particularly emphasized the issue of clustering, which may be ubiquitous in studies of pixel intensity data. Clustering can take many forms, e.g., measurements of different sections of a heart or repeated measurements of the same research participant. Clustering typically has the effect of increasing variance estimates. When one fails to account for clustering, variance estimates may be unrealistically small, resulting in spurious significance. We illustrated several possible approaches to account for clustering, including adjusting standard errors for design effects and modeling the covariance structure within clusters using mixed models. These methods offer great flexibility for dealing with a wide variety of research designs and include the capability for adjusting for covariates and different case weights. Similar methods can be used to account for clustering in both superiority and equivalence analyses. In situations where clustering affects the true cluster mean, µ, but not the difference between measures of the mean, it is possible that clustering will have a much greater impact on superiority analyses than on equivalence analyses

Coronary Evaluation Using Multi-detector Spiral Computed Tomography Angiography: Statistical Design and Analysis

Contrast-enhanced multi-detector row spiral computed tomography (MDCT) has been introduced as a method for non-invasive visualization of coronary artery stenosis. To determine the diagnostic accuracy of MDCT coronary angiography, as compared to the “gold standard” invasive coronary angiography, sensitivity and specificity are estimated (95% Confidence Intervals). Three separate levels of estimation are computed: at the patient level, at the coronary artery level, and at the coronary artery segment level. We review the methodology for the estimation of sensitivity and specificity of non-clustered binary data (patient level analysis) and present a methodology for the estimation of sensitivity and specificity that considers the patient as a cluster and the coronary arteries (or coronary artery segments) as the diagnostic units of the study (DUOS) within each cluster. We also present how to estimate the weighted kappa for the comparison of ordinal measures of stenosis when non-clustered and clustered data are considered and the mean difference for the comparison of continuous measures of stenosis when non-clustered and clustered data are considered. Finally, we present a methods for determining the statistical precision of estimates sensitivity and specificity, weighted kappa and mean difference when clustered data are considered

Complexity as Fitness for Evolved Cellular Automata Update Rules

We investigate the state change behavior of one-dimensional cellular automata during the solution of the binary density-classification task. Update rules of high, low and un- known fitness are applied to cellular au- tomata, thereby providing examples of high and low rates of successful classification. A spread factor, ω, is introduced and investi- gated as a numerical marker of state change behavior. The nature of ω describes complex or particle-like behavior on the part of the cellular automata over the middle region of initial configuration density-distribution, but breaks down at the ends. Because of the lim- itation on ω, a related jump-out term, jot, is selected for incorporation into the finess func- tion for genetic algorithm evolution of update rules. The inclusion of jot in the fitness func- tion significantly reduces the number of gen- erations required to reach high rates of suc- cessful classification (≥90%)

Complexity as Fitness for Evolved Cellular Automata Update Rules

We investigate the state change behavior of one-dimensional cellular automata during the solution of the binary density-classification task. Update rules of high, low and un- known fitness are applied to cellular au- tomata, thereby providing examples of high and low rates of successful classification. A spread factor, ω, is introduced and investi- gated as a numerical marker of state change behavior. The nature of ω describes complex or particle-like behavior on the part of the cellular automata over the middle region of initial configuration density-distribution, but breaks down at the ends. Because of the lim- itation on ω, a related jump-out term, jot, is selected for incorporation into the finess func- tion for genetic algorithm evolution of update rules. The inclusion of jot in the fitness func- tion significantly reduces the number of gen- erations required to reach high rates of suc- cessful classification (≥90%)

Complexity as Fitness for Evolved Cellular Automata Update Rules

We investigate the state change behavior of one-dimensional cellular automata during the solution of the binary density-classification task. Update rules of high, low and un- known fitness are applied to cellular au- tomata, thereby providing examples of high and low rates of successful classification. A spread factor, ω, is introduced and investi- gated as a numerical marker of state change behavior. The nature of ω describes complex or particle-like behavior on the part of the cellular automata over the middle region of initial configuration density-distribution, but breaks down at the ends. Because of the lim- itation on ω, a related jump-out term, jot, is selected for incorporation into the finess func- tion for genetic algorithm evolution of update rules. The inclusion of jot in the fitness func- tion significantly reduces the number of gen- erations required to reach high rates of suc- cessful classification (≥90%)

Hydrogeomorphic Factors and Ecosystem Responses in Coastal Wetlands of the Great Lakes

Gauging the impact of manipulative activities, such as rehabilitation or management, on wetlands requires having a notion of the unmanipulated condition as a reference. An understanding of the reference condition requires knowledge of dominant factors influencing ecosystem processes and biological communities. In this paper, we focus on natural physical factors (conditions and processes) that drive coastal wetland ecosystems of the Laurentian Great Lakes. Great Lakes coastal wetlands develop under conditions of largelake hydrology and disturbance imposed at a hierarchy of spatial and temporal scales and contain biotic communities adapted to unstable and unpredictable conditions. Coastal wetlands are configured along a continuum of hydrogeomorphic types: open coastal wetlands, drowned river mouth and Hooded delta wetlands, and protected wetlands, each developing distinct ecosystem properties and biotic communities. Hydrogeomorphic factors associated with the lake and watershed operate at a hierarchy of scales: a) local and short-term (seiches and ice action), b) watershed /lakewide /annual (seasonal water- level change), and c) larger or year-to-year and longer (regional and/or greater than one-year). Other physical factors include the unique water quality features of each lake. The aim of this paper is to provide scientists and managers with a framework for considering regional and site-specific geomorphometry and a hierarchy of physical processes in planning management and conservation projects

Using Unnatural Amino Acid Mutagenesis To Probe the Regulation of PRMT1

Protein arginine methyltransferase 1 (PRMT1)-dependent methylation contributes to the onset and progression of numerous diseases (e.g., cancer, heart disease, ALS); however, the regulatory mechanisms that control PRMT1 activity are relatively unexplored. We therefore set out to decipher how phosphorylation regulates PRMT1 activity. Curated mass spectrometry data identified Tyr291, a residue adjacent to the conserved THW loop, as being phosphorylated. Natural and unnatural amino acid mutagenesis, including the incorporation of p-carboxymethyl-L-phenylalanine (pCmF) as a phosphotyrosine mimic, were used to show that Tyr291 phosphorylation alters the substrate specificity of PRMT1. Additionally, p-benzoyl-L-phenylalanine (pBpF) was incorporated at the Tyr291 position, and cross-linking experiments with K562 cell extracts identified several proteins (e.g., hnRNPA1 and hnRNP center dot center dot H3) that bind specifically to this site. Moreover, we also demonstrate that Tyr291 phosphorylation impairs PRMT1\u27s ability to bind and methylate both proteins. In total, these studies demonstrate that Tyr291 phosphorylation alters both PRMT1 substrate specificity and protein-protein interacions

Elementary forms and their dynamics: revisiting Mary Douglas

Mary Douglas's oeuvre furnishes the social sciences with one of the most profound and ambitious bodies of social theory ever to emerge from within anthropology. This article uses the occasion of the publication of Fardon's two volumes of her previously uncollected papers to restate her core arguments about the limited plurality of elementary forms of social organisation, about the institutional dynamics of conflict, and about conflict attenuation. In reviewing these two volumes, the article considers what those anthropologists who have been sceptical either of Douglas's importance or of the Durkheimian traditions generally, will want from these books to convince them to look afresh at her work. It concludes that the two collections will provide open-minded anthropologists with enough evidence of the creativity and significance of her achievement to encourage them to reopen her major theoretical works. An internal critique of some aspects of Douglas's handling of her arguments is offered, before the conclusion identifies the wider significance of her arguments for the social science

Lake-level Variability and Water Availability in the Great Lakes

Key components of water availability in a hydrologic system4 are the amount of water in storage and the variability of that amount. In the Great Lakes Basin, a vast amount of water is stored in the lakes themselves. Because of the lakes’ size, small changes in water levels cause huge changes in the amount of water in storage. Approximately 5,439 mi3 of water, measured at chart datum, is stored in the Great Lakes. A change of 1 ft in water level over the total Great Lakes surface area of 94,250 mi2 means a change of 18 mi3 of water in storage. Changes in lake level over time also play an important role in human activities and in coastal processes and nearshore ecosystems, including development and maintenance of beaches, dunes, and wetlands. The purpose of this report is to present recorded and reconstructed (pre-historical) changes in water levels in the Great Lakes, relate them to climate changes of the past, and highlight major water-availability implications for storage, coastal ecosystems, and human activities. Reconstructed water-level changes have not been completed for all Great Lakes; consequently, this report presents these changes primarily for Lakes Michigan and Huron, with some reference to Lake Superior also