Crust and upper mantle structure in the region of Barbados and the Lesser Antilles

The Lesser Antilles form one of only two island arcs that occur in the Atlantic Ocean. Bathymetric, gravity, magnetic, and seismic reflection data were collected by HMS HECLA during 1971 in an area bounded by latitudes 12 54’ N and 13 54' N, and longitudes 57 W and 61 10' W, including the islands of St. Lucia, St. Vincent, and Barbados. These data are reduced and interpreted in conjunction with seismic refraction data from an experiment run in 1972 and data from other published and unpublished sources. The structure of the upper sedimentary layers is derived from the seismic reflection records. The crustal structure is modelled two dimensionally using a non-linear optimisation technique to fit the observed gravity and seismic refraction data. The island arc and the Barbados Ridge are examined in detail, and the nature of a ridge running eastward from St. Lucia into the Atlantic Ocean basin is investigated. Magnetic anomalies are treated by direct modelling, magnetic to gravity transformation, and analysis of the power spectrum. The seismicity of the eastern Caribbean is considered with respect to possible plate motions, and maps of focal depth and energy release are presented. The mechanism and causes of subduction beneath the Lesser Antilles are discussed. The possible gravity anomaly caused by subducted lithosphere is estimated and its effect on the determination of the crustal structure examined. The influence of the relative motions between the North and South American plates on the development of the Caribbean and the Lesser Antilles is studied. Some ideas on the origin and growth of the Barbados Ridge and the island arc are put forward. Geophysical data profiles, and computer programs for reduction and interpretation of data are presented in appendices

Using 3D-printed analogues to investigate the fall speeds and orientations of complex ice particles

The terminal velocity vt and preferred orientations of ice particles has been investigated using 3D-printed analogues sedimenting in glycerine solutions at Reynolds numbers typical of natural ice particles falling in air. Twenty two different particle geometries were investigated: these included both simple shapes, such as hexagonal plates, as well as more complex particles, such as bullet rosettes, plate-polycrystals and aggregates. Two widely-used prescriptions for ice particle fall speed were tested against the new experimental data, to determine the accuracy of their predictions. We show that for open particles, such as bullet rosettes and aggregates, one of these prescriptions systematically overestimates vt, by as much as 80%

A search for massive neutral bosons in orthopositronium decay

We have searched for an exotic decay of orthopositronium into a single photon and a short-lived neutral boson in the hitherto unexplored mass region above 900 ${\rm keV}/{\it c}^{2}$, by noting that this decay is one of few remaining candidates which could explain the discrepancy of the orthopositronium decay-rate. A high-resolution measurement of the associated photon energy spectrum was carried out with a germanium detector to search for a sharp peak from this two-body decay. Our negative result provides the upper-limits of\mbox{ }$2.0 \times 10^{-4}$ on the branching ratio of such a decay in the mass region from 847 to 1013 ${\rm keV}/{\it c}^{2}$, and excludes the possibility of this decay mode explaining the discrepancy in the orthopositronium decay-rate.Comment: a LaTeX file (text 7 pages) and a uuencoded gz-compressed PostScript file (text 7 pages + figures 4 pages

Describing interruptions, multi-tasking and task-switching in the community pharmacy: A qualitative study in England

Background: There is growing evidence base around interruptions and distractions in the community pharmacy setting. There is also evidence to suggest these practices may be associated with dispensing errors. Up to date, qualitative research on this subject is limited. Objective: To explore interruptions and distractions in the community setting; utilising an ethnographic approach to be able to provide a detailed description of the circumstances surrounding such practices. Setting: Community pharmacies in England, July to October 2011. Method: An ethnographic approach was taken. Non participant, unstructured observations were utilised to make records of pharmacists’ every activities. Case studies were formed by combining field notes with detailed information on pharmacists and their respective pharmacy businesses. Content analysis was undertaken both manually and electronically, utilising NVivo 10. Results: Response rate was 12% (n=11). Over fifteen days, a total of 123 hours and 58 minutes of observations were recorded in 11 separate pharmacies of 11 individual pharmacists. The sample was evenly split by gender (female n=6; male n=5) and pharmacy ownership (independent n=5; multiple n=6). Employment statuses included employee pharmacists (n=6), owners (n=4) and a locum (n=1). Average period of registration as a pharmacist was 19 years (range 5-39 years). Average prescriptions busyness of pharmacies ranged from 2,600 – 24,000 items dispensed per month. Two key themes were: “Interruptions and task-switching” and “distractions and multi-tasking.” All observed pharmacists’ work was dominated by interruptions, task-switches, distractions and multi-tasking, often to manage a barrage of conflicting demands. These practices were observed to be part of a deep-rooted culture in the community setting. Directional work maps illustrated the extent and direction of task switching employed by pharmacists. Conclusions: In this study pharmacists’ working practices were permeated by interruptions and multi-tasking. These practices are inefficient and potentially reduce patient safety in terms of dispensing accuracy

Chemical Kinetic Models for HCCI and Diesel Combustion

Predictive engine simulation models are needed to make rapid progress towards DOE's goals of increasing combustion engine efficiency and reducing pollutant emissions. These engine simulation models require chemical kinetic submodels to allow the prediction of the effect of fuel composition on engine performance and emissions. Chemical kinetic models for conventional and next-generation transportation fuels need to be developed so that engine simulation tools can predict fuel effects. The objectives are to: (1) Develop detailed chemical kinetic models for fuel components used in surrogate fuels for diesel and HCCI engines; (2) Develop surrogate fuel models to represent real fuels and model low temperature combustion strategies in HCCI and diesel engines that lead to low emissions and high efficiency; and (3) Characterize the role of fuel composition on low temperature combustion modes of advanced combustion engines

An Experimental and Computational Investigation of n-Dodecane Ignition and Chemical Kinetics

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90619/1/AIAA-2011-90-831.pd

Farmer, Agent, and Specialist Perspectives on Preferences for Learning Among Today\u27s Farmers

Few studies have examined the types of educational delivery methods preferred by farmers (Eckert & Bell, 2005; Eckert & Bell, 2006). The research project reported here explored the preferred learning methods of farmers in Louisiana, Tennessee, and Virginia. Data on learning methods collected directly from farmers were compared with preferred teaching methods of Extension agents and specialists. The findings should shape agent and specialist perspectives on appropriate educational delivery methods when educating farmers and working towards farmer adoption of new practices

PREDICTING THE DATE OF FIRST CATCH OF THE CORN EARWORM, HELICOVERPA ZEA, IN CENTRAL U.S.

This paper develops predictive (or correlative) models for the date of first catch of the com earworm, Helicoverpa zea, as a basis for identifying biotic and abiotic factors that influence dispersal and migration. Data described in Goodenough et al. (1988, J. Econ. Entomol.) on the catch of H. zea gathered at over 150 sites predominantly in the central U.S. from 1983 to 1986 are analyzed. The dependent variables, Y1 and Y2, are date of first meaningful catch and date when cumulative catch exceeds 5, respectively; the independent variables are latitude, longitude and elevation of the site. Outstanding among the findings are the following : 1) There is no statistical evidence based on all the data that the slopes of the simple linear regression models of Y2 on latitude differ among the four years. The common slope estimate is 8.11 days/degree, the intercepts differ by as many as 16 days, and the combined model has r2 = 0.69. 2) There is no statistical evidence based on the data in the central U.S. that the partial slopes of the multiple regression models of Y2 on latitude and longitude differ among the four years. The common partial slope estimates are 7.36 and -1.27 days/degree, the intercepts differ by as many as 17 days, and the combined model has R 2= 0.69. Second order terms are not significant . 3) An exploratory analysis using GIS mapping software suggests that elevation is also a significant predictor variable. The suggestion is confirmed in multiple regression models for both Y1 and Y22= 0.71 and 0.72 respectively. The intercepts differ by as many as 20 and 17 days, respectively, over the four years . These results imply that the time of fi!\u27st appearance at any location in the central U.S. could be predicted once the date of first appearance in South Texas is ascertained. They also demonstrate the utility of analyzing residuals using GIS mapping software. Research is in progress to investigate other possible predictor variables including soil moisture, soil temperature and precipitation

Understanding Lung Cancer Resources and Barriers among Worksites with Mostly Male Employees in Eight Rural Kentucky Counties: A Focus Group Discussion

Kentucky has the highest cancer incidence and mortality rates in the United States, and lung cancer is Kentucky\u27s leading cause of cancer deaths. Males in Kentucky have higher lung incidence and mortality rates than females. Through support from the SelfMade Health Network, Kentucky developed a Regional Resource Lead Organization that collaboratively developed a multi-component worksite intervention on lung cancer among male populations. The intervention targets eight Kentucky counties. The first component and focus of this manuscript included focus group meetings with organizational representatives in each county that provide health, educational, and social services to men and worksites. The focus groups discussed four distinct areas: (a) lung cancer-related resources and services in each county; (b) perceived ways men in worksites learn about and access health-related services; (c) identification of potential challenges and barriers to reaching men in worksites; and (d) creation of linkages and potential partnerships between community organizations and worksites. Forty-five organizational representatives participated in the eight focus groups. Most resources and services discussed were related to tobacco treatment. Employers were the most commonly perceived way men learn about and access health-related services, while attitudes and behaviors were the most commonly perceived barriers preventing men from accessing services. The most common potential linkages and partnerships across all areas were community organizations and groups, employers, health-care providers, and mass media. Partnering with employers may provide an opportunity to reach males with lung cancer prevention and control resources and services