Low cost concentrator

The key to concentrator cost effectiveness is the proper design of the reflector surface panels. The low cost concentrator reflective surface design is based on use of a thin, backsilvered mirror glass reflector bonded to a molded structural plastic substrate. This combination of reflective panel material offers excellent optical performance at low cost. The design approach, rationale for the selected configuration, and the development status are described. Reflective panel development and demonstration results are also presented

Phylogenetic Analysis of Borrelia Species Detected in Small Mammals and Ticks in Florida

The infection prevalence of Borrelia burgdorferi, the etiological agent of Lyme disease, was estimated among small mammals and ticks at two sites in northern Florida using molecular methods. Analysis of the B. burgdorferi flagellin gene in samples extracted from the ticks and small mammals was used to construct a phylogenetic tree. The phylogenetic tree was used to compare partial flagellin gene sequences of the Borrelia strains from Florida with reference Borrelia strains. The infection prevalences of small mammals at the University of North Florida and Guana River State Park were 90% and 47%, respectively, with 6 of 7 small mammal species testing positive. Forty-two adult Ixodes scapularis ticks were also tested at each site: 20/42 tested positive at UNF (48 %) and 5/42 tested positive at Guana River (12 %). The neighbor-joining phylogenetic tree showed that the Florida Borrelia strains were 98-99% genetically similar to reference strains of B. burgdorferi sensu stricto (confirmed Lyme disease agent) and B. bissettii (pathogenicity undetermined). The findings confirm the presence of specific Borrelia species in northern Florida; however, their relationship to human Lyme disease in Florida is the subject of ongoing studies

The Open Class Authorship Attribution Problem: A Comparison of Mixture-of-Experts Methods within the JGAAP Framework

In this paper, we seek to describe, test, evaluate, and compare methods of open class attribution that utilize multiple unique closed class attributions in a voting framework. By applying statistical techniques to the proportion of closed class attributions indicating individual candidate authors, we seek to determine if the author is present in a set of suspected authors or not. The final answer to an open class attribution problem is either one of the authors in the set of candidate authors or None of the above. We test nine different methods of open class attribution grouped into three distinct voting paradigms. We find that the most effective method is a voting method in which each closed class attribution votes equally for its top two most likely authors. Accuracies in this method are statistically better than chance and, in total, are the best out of all nine methods

The Relationship Between Critical Thinking Skills and Perceived Self-Efficacy in Associate Degree Nursing Students

The purpose of this descriptive, correlational study was to determine if a relationship exists between critical thinking skills and self-efficacy in Associate Degree nursing students. A convenience sample of 30 nursing students in their second year of an Associate Degree RN program was used. The framework for this study utilized Bandura\u27s social cognitive theory and Benner\u27s nursing theory of skill acquisition and development. Critical thinking skills were measured by the California Critical Thinking Skills Test. Self-efficacy was measured by the Generalized Perceived Self-Efficacy Scale. Demographic data of age, gender, marital status, number of dependents, employment status, and income were obtained to determine if there were any relationships or differences related to critical thinking or selfefficacy. A positive correlation was found between critical thinking skills and perceived self-efficacy (r =.40, p = .03). A replication of this study with a larger sample would be recommended. A longitudinal study might indicate changes that occur as the student progresses in the learning process with regard to critical thinking skills and self-efficacy

Assessing and Analyzing Near-Surface Radar Snow Accumulation Layers at Summit, Greenland

High vertical-resolution 0.5&mdash2 GHz frequency-modulated continuous-wave radar data collected near Summit on the Greenland Ice Sheet reveal continuous horizons connecting the GRIP and GISP2 deep ice cores. Traced radar horizons to 150 meters depth are compared to physical properties, age-depth relationships, and accumulation rates from ice cores near Summit. Having established the radar horizons as annual accumulation markers, a 350-year record of accumulation rate is derived and analyzed spatially and temporally. Accumulation characteristics such as spatial noise, long-term accumulation rate, and climate fluctuations are determined. Averaging accumulation across 1000&mdash2000 m eliminates most spatial noise associated with small-scale surface perturbations, providing a good approximation of the local accumulation rate. Overall, a detailed record of accumulation is gained, indicating that near-surface radar surveys can take the place of shallow ice cores for examining accumulation history, improving knowledge of spatial and temporal variability, spatial and temporal noise, and other accumulation characteristics