Double Layer Effects on Shock Wave Propagation

An analysis and assessment of two mechanisms in plasma shock interactions was conducted under conditions typically encountered in a weakly ionized glow discharge. The mechanisms of a spatially-dependent electron temperature and additional electron impact ionization at the shock front were examined for effects on shock structure and propagation. These mechanisms were incorporated into an existing one-dimensional, time-dependent, fluid dynamics code that uses the Riemami problem as a basis and numerically solves the Euler equations for two fluids: the neutral gas and the charged component. The spatial variation in electron temperature was modeled as a shock-centered rise in temperature. Additional ionization was modeled by incorporating a variable electron temperature and a quasi-kinetic collision function, for both unrestricted ionization and ionization mitigated by ion-electron recombination. Introduction of a spatial variation in electron temperature resulted in a broadening and strengthening of the electric field associated with the electronic double layer (EDL) at the shock front. Results of unrestricted ionization were a broadening and strengthening of the electric field associated with the EDL, acceleration of the neutral shock front, and the development of a neutral precursor ahead of the shock. Ion-electron recombination was seen to reduce these effects

Morphological, Genetic, and Environmental Characterization of an Unusual Population of \u3ci\u3eIsoetes\u3c/i\u3e (Isoetaceae, Lycopodiophyta)

A large and unusual population of Isoetes (Isoetaceae, Lycopodiophyta) in the DeSoto National Forest, Wayne County, Mississippi, was studied to determine if the individuals there represent a new species or if they represent part of the variation of the one primary species of the longleaf pine belt of Mississippi, Isoetes louisianensis, which it most closely resembles. The unusual population and specimens of known Isoetes louisianensis were examined comparatively based on morphology, megaspore ornamentation, examination of habitat characteristics, and phylogenetic analysis of DNA sequence data from the nuclear internal transcribed spacer 1 and 2 (ITS) and the 5.8S ribosomal gene. No differences were discovered between the populations in DNA sequence data, small differences were discovered in megaspore ornamentation and habitat, and more significant differences were discovered in morphology, although all of the differences were based on small sample size. Thus, the results of this study are inconclusive as to the species status of the unusual Isoetes population. However, the detailed environmental data collected in the drainage do show that senescence (loss of leaves) closely follows water levels, not temperatures or seasons, as some have hypothesized. This study augments scientific understanding of Isoetes louisianensis, considering that much about this species is still unknown due to many new, recent discoveries of populations, similarities in appearance with other species of Isoetes, natural occurrences in Isoetes of cross-fertilization with the production of sterile hybrids, variations in ploidy level, and the need for scanning electron microscopy to carefully observe megaspore ornamentation. Plans have been made to continue assessing the v unusual Isoetes population and typical Isoetes louisianensis populations based on chromosome numbers, vegetative anatomy, and phylogenetic analysis of additional DNA regions

BELOWGROUND CHARACTERISTICS OF DOMINANT COASTAL DUNE GRASSES AND POTENTIAL COMMUNITY-LEVEL EFFECTS ON COASTAL EROSION

Natural dunes arise out of complex relationships between ecological, hydrological, and geological processes and are important for reducing erosion along coastlines. Aboveground structures of coastal dune grasses are known to impact erosional dynamics, and recent studies have shown that belowground structures—such as roots, rhizomes, and belowground stems— may be important in erosional resistance. My objectives were to 1) characterize above- and belowground characteristics of prominent dune grasses and 2) combine these data with functional group abundances and distribution to evaluate community effects on two adjacent locations of distinctive morphology and erosional characteristics and their response to storm disturbance. Whole plant samples of four dominant dune grasses—Ammophila breviligulata, Spartina patens, Panicum amarum, and Uniola paniculata—were collected from an unmanaged foredune and examined for above- and belowground characteristics. To assess the relationship among plant community, dune morphology, and storm effects, transects were also established in two locations of differing morphology along the same foredune and plant community data collected pre- and post-Hurricane Dorian. The four focal species differed in their suites of characteristics, indicating that these grasses may have species-specific impacts on dune erosional dynamics that arise from both above- and belowground factors. Plant community analyses vii further support that understanding species characteristics within a functional group at a given location may be critical in understanding the complex net effects of plant communities on erosional dynamics. This study demonstrates the necessity of considering belowground features of dominant vegetation as well as aboveground for understanding erosional dynamics in natural dune systems

Resignification, recontextualisation and reclamation of colonial landscape memorials in the Latin American context

Recent reactions to colonial-era memorials have contributed to a renewal of interest in memorialisation as a focal point for social justice and equity. In the Latin American context, colonial memorials are visual links that are deeply-rooted elements of the region’s identity. This paper focuses on three landscape memorial sites in Latin America as carriers of meaning. The first case study is the Equestrian Sebastian de Belalcázar memorial space in Popayán, Colombia. The monument of this Spanish conqueror was placed on Morro de Tulcán, a sacred site for the Pubenenses tribe. The colonial narrative, in this case, is one of oppression in which Spanish heritage is favoured over indigenous culture. The second case study is the Isabella La Catolica monument in La Paz, Bolivia. This statue was initially established to be a paradigmatic model of European women, beauty and virtue, but it has become a symbol of discrimination against native women. The third case is the equestrian monument of 19th-century war Chilean hero and politician General Manuel Jesús Baquedano González. Located in Santiago de Chile, this figure was seen by many as a symbol of how the Chilean elite repressed indigenous people. Each of the three statues has experienced a range of reactions that reveal counter-narratives to those imposed by the insertion of the colonial figures into the landscape. The responses include removal, dressing and graffiti; we classify these interventions as reclamation, resignification and recontextualisation.  Walter Hood (2019) argues, “landscape is the last democratic space we have, and we need to fill it with diverse voices.

The Role of Situational and Dispositional Factors on Sub-Optimal Performance

Pressure is known to decrease performance for well-practiced tasks. Research has found that pressure decreases performance for those with high self-consciousness when distracted, but the effects of pressure and distraction are not known for those with low self-consciousness. Therefore, the purpose of this study was to assess whether a distraction would improve the performance of those with low self-consciousness. A 2 (self-consciousness) x 2 (distraction) analysis of covariance (covariates emotional control, performance distance) factorial design was used to assess putting performance for 125 undergraduate participants. Results revealed that distraction negatively affected performance for both self-consciousness groups, but results indicated that there were no performance effects for pressure, level of self-consciousness, or emotional reactivity. Methodological issues are addressed

Exploring sense of community among small-scale sport event volunteers

Research question: In response to claims that sport event research over emphasizes economic outcomes and mega-event contexts, this research sought to both assess a scale that measures sense of community among small-scale sport event volunteers, and empirically test if the event volunteer experience enhances sense of community. Research methods: The six-factor Sense of Community in Sport Scale (SCS) was utilized to collect pre- and post-event data from a population of 253 (N = 253) event volunteers in the Niagara region of Canada. Results and findings: Model testing indicated all but one SCS factor, Competition, showed statistical fit with the event volunteer data. Analysis of variance revealed three SCS factors, Common Interest, Equity in Administrative Decisions and Social Spaces, were statistically enhanced following the event. Implications: The findings provide theoretical support for Warner and Dixon's Sport and Sense of Community theory and highlight the positive social impact of small-scale sport events within a community for volunteers

Sexual Dimorphism and Intersexual Differences in Resource Allocations of a Dioecious Shrub, Lindera melissifolia (Walt.) Blume

Morphometric data were gathered to make intersexual comparisons on the morphology and reproductive resource allocation patterns of the rare, dioecious shrub, Lindera melissifolia. Females produced significantly fewer flowers and leaves than did males. No other significant differences could be detected in morphology. Female clones exhibit low area coverage and low stem density, which suggests higher costs of reproduction. If this is the case, the deficits produced in resource allocations directed toward sexual reproduction seem to result in increased mortality and/or reduced vegetative reproduction

From Science to Librarianship: Career Motivations of the Scientist-Turned-Librarian

Why might someone with science training pursue an information career? This secondary analysis of the Workforce Issues in Library and Information Science (WILIS) study compares those who earned a natural science degree prior to the LIS program with others who did not. The results point to more similarities than differences. All LIS graduates showed broad agreement on job motivations, values, and satisfaction; however, some differences were found. Science majors were less interested in school libraries and more in special libraries. Scientists were more likely to self-identify as "information professional" alone or in tandem with "librarian" and more likely to cite computer interest as one motivation. Science graduates were significantly more likely to claim responsibilities for academic research and publications, database development, and "other" IT and consulting. Very few entrants to LIS programs have science degrees, but the potential exists to attract more