Existence of tracial states on reduced group C*-algebras

Let $G$ be a locally compact group. It is not always the case that its reduced C*-algebra $C^*_r(G)$ admits a tracial state. We exhibit closely related necessary and sufficient conditions for the existence of such. We gain a complete answer when $G$ compactly generated. In particular for $G$ almost connected, or more generally when $C^*_r(G)$ is nuclear, the existence of a trace is equivalent to amenability. We exhibit two examples of classes of totally disconnected groups for which $C^*_r(G)$ does not admit a tracial state.Comment: The proof of Remark 2.6 (ii) has been corrected, and a typo has been fixe

Iconography profiles

This thesis examines the connection between art and its viewer and how this understanding of audience interaction impacts the way I create my work. The inspiration and spiritual basis for my work is explored to show the meaning behind my thesis collection. This document also explores the methodology and processes I use in the creation of my art. I also discuss the way in which my work is displayed with consideration towards lighting and the creation of the art being exposed from start to finish for my audience. The concluding thoughts in this thesis sum up the importance of religious symbolism and my recreation of the appropriated imagery that I have given a new voice to through my methodology and interpretation as an artist

Isolated photon production in deep inelastic scattering at HERA

This thesis presents measurements of isolated photon production in deep inelastic ep scattering made with the ZEUS detector at HERA using an integrated luminosity of 320 pb-1. Measurements were made in the isolated-photon transverse-energy and pseudorapidity ranges 4 5 GeV. Differential cross sections are presented for inclusive isolated photon production as functions of Q^2, x, E_T and eta. Leading-logarithm parton-shower Monte Carlo simulations and perturbative QCD predictions give a reasonable description of the data over most of the kinematic range. To increase the precision of the measurement, a study was undertaken to improve the Monte Carlo description of electromagnetic showering in the ZEUS calorimeter. This utilised isolated electromagnetic clusters from ZEUS data to which Monte Carlo event samples with varying parameters for electromagnetic showering were fitted. These improvements have been adopted in the standard ZEUS detector simulation and were also shown to improve electron identification. For the main isolated photon analysis a range of methodologies for photon clustering and identification, isolation and signal extraction were investigated and the optimal methods were chosen. As a result of these refinements and the improved electromagnetic shower modelling, the systematic errors decreased significantly, typically by a factor of three when compared to the same phase space in the previous ZEUS publication. In addition the luminosity was increased threefold and the phase space was expanded. These two improvements brought about a factor three reduction in statistical uncertainty

The Geology, Geochemistry and Ecology of a Shallow Water Submarine Hydrothermal Vent Bahía Concepción, Baja California Sur, México

I studied a shallow water (O-13m water depths) hydrothermal vent in Bahía Concepción, Baja California Sur, México. Investigations using side-scan sonar and SCUBA suggested that the submarine hydrothermal activity is mainly controlled by a NW-SE trending onshore-offshore fault. Compared to seawater, vent fluids are enriched in Ca, Mn, HC03, SiO2, B, As, Li, Fe, Rb, and Sr, and depleted in Na, Cl, Mg, and S04, with calculated end-member temperatures up to 220°C. The vent gas is primarily nitrogen, carbon dioxide, and methane, and the geochemistry of the gas suggests that it may be derived from the thermal alteration of algal matter. The submarine hydrothermal activity is negatively affecting abundances and diversity of infaunal assemblages. The carbon and nitrogen stable isotope ratios of some of the animals feeding around the vent, particularly the sea cucumber Holothuria inhabilis, were significantly different than those from the same species collected away from venting activity

According to a new study : when bad journalism meets questionable science

Accurately reporting scientific studies remains a challenge for journalists. Often lacking any formal background in science, journalists are expected to communicate the complex findings of scientific research in such a way that average readers can understand. As a result, news coverage tends to exaggerate, misrepresent, or sensationalize the findings of scientific studies. This report examines the common errors that journalists make when reporting on scientific studies, as well as the issues in modern scientific research that contribute to this problem. While total scientific literacy in journalism remains a lofty ideal, the democratizing force of the Internet not only holds journalists more accountable in their reporting, but also provides platforms for skeptics and experts to weigh in on the news treatment that studies receive.Journalis

Terms and Concepts for Yield, Crop Loss, and Disease Thresholds

The initial report (14) of a subcommittee of the APS Plant Disease Losses Committee dealt with terms and concepts relating to the measurement of disease intensity to obtain accurate and precise quantitative information on the relationship between disease intensity (stimulus = X) and yield or yield loss (response = Y). In addition to standardizing the terms and concepts for the measurement of disease intensity, members of the full committee identified a need to clarify and standardize terms and concepts pertaining to yield, crop loss, and disease thresholds. A second subcommittee was formed to accomplish this task. This report describes concepts concerning reference points for yield and crop loss as well as a hierarchy for threshold terms, then presents a list of terms and definitions to standardize terminology for crop loss assessment