Sediment transport and erosion in the Fourchon area of Lafourche parish

NASA aerial photography in the form of color infrared and color positive transparencies is used as an aid in evaluating the rate and effect of erosion and sediment transport in Bay Champagne Louisiana

AERODYNAMICS AND AEROACOUSTICS SURVEY FOR A LOW SPEED SUBSONIC JET OPERATING AT MACH 0.25

The purpose of this work is to study and characterize, in laboratory, the aerodynamics of a free jet operating at subsonic regime and identify its acoustic signature. This study aims to analyze the fundamental role of turbulent flow structures in the total noise produced at different Mach numbers. This work is focused at low speed subsonic jets operating at Mach number 0.25. The research is done by analyzing the data obtained in experiments using Pitot tube, hot-wire anemometer and acoustic measurements. This work also describes the experimental procedures for each step of analysis, as well as the characteristics of jet noise facility. The data from measurements with Pitot tube is used to study the mean velocity profiles. The average properties are also analyzed with anemometry system, likewise used to study the turbulent intensity of eleven axial lines, ranging from the center line to the edge of the nozzle (lipline). These results are compared with the literature and is verified the accuracy of hot-wire anemometers for turbulent intensities lower than 15%. A database with the sound pressure level as a function of frequency is constructed from experiments serving as data for further numerical analysis to solve this problem

Diagnostic Medical Errors: Patient\u27s Perspectives on a Pervasive Problem

Introduction. The Institute of Medicine defines diagnostic error as the failure to establish an accurate or timely explanation for the patient\u27s health problem(s), or effectively communicate the explanation to the patient. To our knowledge, no studies exist characterizing diagnostic error from patient perspectives using this definition. Objective. We sought to characterize diagnostic errors experienced by patients and describe patient perspectives on causes, impacts, and prevention strategies. Methods. We screened 77 adult inpatients at University of Vermont Medical Center and conducted 27 structured interviews with patients who experienced diagnostic error in the past five years. We performed qualitative analysis using Grounded Theory. Results. In the past five years, 39% of interviewed patients experienced diagnostic error. The errors mapped to the following categories: accuracy (30%), communication (34%) and timeliness (36%). Poor communication (13 responses) and inadequate time with doctors (7) were the most identified causes of errors. Impacts of errors included emotional distress (17 responses), adverse health outcomes (7) and impaired activities of daily living (6). Patients suggested improved communication (11 responses), clinical management (7) and access to doctors (5) as prevention strategies. For communication, patients rated talk to your doctor highest (mean 8.4, on 1-10 Likert scale) and text message lowest (4.8). Conclusions/Recommendations. Diagnostic errors are common and have dramatic impact on patients\u27 well-being. We suggest routine surveillance to identify errors, support for patients who have experienced errors, and implementation of patient and provider checklists to enhance communication. Future studies should investigate strategies to allow care providers adequate time with patients.https://scholarworks.uvm.edu/comphp_gallery/1246/thumbnail.jp

Speleothem U-series constraints on scarp retreat rates and landscape evolution: an example from the Severn valley and Cotswold Hills gull-caves, UK

Modelling landscape evolution requires quantitative estimates of erosional processes. Dating erosional landscape features such as escarpments is usually difficult because of the lack of datable deposits. Some escarpments and valley margins are associated with the formation of mass-movement caves, sometimes known as ‘gull’ or ‘crevice’ caves, which are typically restricted to within 0.5 km of the valley margin or scarp edge. As in other caves, these mass-movement cavities may host speleothems. As gull-caves develop only after valley incision, uranium-series dating of speleothems within them can provide a minimum age for the timing of valley excavation and scarp formation. Here we present data from several gull-caves in the Cotswold Hills, which form the eastern flank of the Severn valley in southern England. U-series ages from these gull-caves yield estimates for both the minimum age of the Cotswold escarpment and the maximum scarp retreat rate. This is combined with data from geological modelling to propose a model for the evolution of the Severn valley and the Cotswold Hills. The data suggest that the location of the escarpment and regional topography is determined not by valley widening and scarp retreat, but by the in situ generation of relief by differential erosion

Effects of macrofauna on acoustic backscatter from the seabed: Field manipulations in West Sound, Orcas Island, Washington, U.S.A.

Previous observations with a bottom-mounted, radially scanning sonar (BAMS) at 40 kHz suggested that macrofaunal activities influence low-angle, acoustic backscatter from seafloor sediments. In order to test that possibility experimentally, we measured and modeled time series of backscatter strength at both 40 and 300 kHz prior to manipulation and then introduced several macrofaunal species at known abundances to randomly selected locations within the ensonified area. We worked in West Sound, Orcas Island, Washington, at a water depth of 20.4 m and for the more frequently recorded 40-kHz series extracted effects by the time-series method known as intervention analysis, wherein the intervention was the experimental alteration. We observed increased backscatter from patches of the small protobranch bivalve Acila castrensis, and of the cockle Clinocardium nuttali, from bait used as chum for fishes and crabs, and from tethered crabs (Cancer magister); other treatments showed no significant change. All of the effective treatments involved increased backscatter at 300 kHz from animals that have obvious hard parts or air bladders. Power calculations for intervention analysis and geoacoustic modeling suggest that failure of other treatments to show significant effects on backscatter strength stems from the small size of the organisms and structures used relative to the 40-kHz wavelength (3.7 cm) and to low sound-speed contrasts between surficial sediments at this site and overlying water (at both frequencies), producing low backscatter levels from both volume heterogeneity and surface microtopography. This experiment demonstrates, however, that low-angle acoustic backscatter can be used to observe at least some populations of benthic animals over a large area (ca. 8000 m2) and that intervention analysis can be a useful tool where logistics permit repeated observation but few or no spatial replicates—frequently the case in ecological manipulations

Adsorption of benzene on Si(100) from first principles

Adsorption of benzene on the Si(100) surface is studied from first principles. We find that the most stable configuration is a tetra-$\sigma$-bonded structure characterized by one C-C double bond and four C-Si bonds. A similar structure, obtained by rotating the benzene molecule by 90 degrees, lies slightly higher in energy. However, rather narrow wells on the potential energy surface characterize these adsorption configurations. A benzene molecule impinging on the Si surface is most likely to be adsorbed in one of three different di-$\sigma$-bonded, metastable structures, characterized by two C-Si bonds, and eventually converts into the lowest-energy configurations. These results are consistent with recent experiments.Comment: 4 pages, RevTex, 2 PostScript gzipped figure

Popular music, psychogeography, place identity and tourism: The case of Sheffield

Tourism and cultural agencies in some English provincial cities are promoting their popular music ‘heritage’ and, in some cases, contemporary musicians through the packaging of trails, sites, ‘iconic’ venues and festivals. This article focuses on Sheffield, a ‘post-industrial’ northern English city which is drawing on its associations with musicians past and present in seeking to attract tourists. This article is based on interviews with, among others, recording artists, promoters, producers and venue managers, along with reflective observational and documentary data. Theoretical remarks are made on the representations of popular musicians through cultural tourism strategies, programmes and products and also on the ways in which musicians convey a ‘psychogeographical’ sense of place in the ‘soundscape’ of the city

Self-build in the UK and Netherlands:mainstreaming self-development to address housing shortages?

This paper examines approaches to self or custom-build in the Netherlands and the UK to offer comparative insights into self- and custom-built housing contexts and cultures, and specifically, the relationships with local and strategic planning arrangements. The paper reviews arguments for self-build as a means to address housing shortages and examines the evidence of completions in practice. It positions the discussion in light of arguments that self-build can become a mainstream source of housing provision. The paper critically considers the role of think tanks in advocating housing policy solutions. Adopting a social constructionist perspective, the paper examines the work of the National Self-Build Association which has devised and implemented an action plan to promote the growth of self-build housing in the UK. Almere, which is located east of Amsterdam, is one of the case studies explored to inform thinking around self-build in the devolved UK. The conclusions tease out some of the implications for democratic and technocratic arguments around self-development and the right to design and build one’s home