Light hadronic physics using domain wall fermions in quenched lattice QCD

In the past year domain wall fermion simulations have moved from exploratory stages to the point where systematic effects can be studied with different gauge couplings, volumes, and lengths in the fifth dimension. Results are presented here for the chiral condensate, the light hadron spectrum, and the strange quark mass. We focus especially on the pseudoscalar meson mass and show that, in small volume, the correlators used to compute it can be contaminated to different degrees by topological zero modes. In large volume a nonlinear extrapolation to the chiral limit, e.g. as expected from quenched chiral perturbation theory, is needed in order to have a consistent picture of low energy chiral symmetry breaking effects.Comment: To appear in the proceedings of Lattice 2000 (spectrum), Bangalore, India. Work done as part of the RIKEN/BNL/Columbia Collaboration. (4 pages) - Reference adde

Indigenous wellbeing in Australia: evidence from HILDA

This study explores the subjective wellbeing of Indigenous Australians. Abstract Report focusses on mean levels of self-reported life satisfaction, inequality in life satisfaction within the Indigenous and non-Indigenous Australian populations, and the prevalence and severity of dissatisfaction with one’s life. Evidence on differences in the determinants of life satisfaction between Indigenous and non-Indigenous Australians is provided. Results indicate that Indigenous life satisfaction peaked in 2003 and has since declined. We also find that inequality in life satisfaction is greater for Indigenous than non-Indigenous Australians. Despite a downward trend in the level of dissatisfaction for non-Indigenous Australians, dissatisfaction among Indigenous Australians has remained relatively unchanged

Extracts of Trichostema lanatum inhibit the growth of gram-positive bacteria and an Escherichia coli ΔtolC mutant strain

The Chumash Native Americans of Southern California have well-documented traditions of using plants for medicinal purposes. If a specific plant has traditionally been used for the treatment of cuts, wounds and infections, it may contain chemicals with anti-bacterial properties. One plant that fits these criteria is Trichostema lanatum (woolly blue curls). We tested extracts of T. lanatum for their ability to inhibit the growth of a variety of bacteria. Because of the widespread use of antibiotics over the past sixty years bacteria are evolving greater resistance to known antibiotics, but unfortunately the rate of antibiotic discovery has diminished during the past twenty years. Therefore, novel and effective antibiotics are essential for the continued treatment of bacterial infections. A panel of bacteria representing both gram-negative and gram-positive species as well as organisms from a variety of ecological niches was used to evaluate the anti-bacterial properties of methanolic extracts of T. lanatum. An Escherichia coli ΔtolC mutant was also used to test whether or not drug-efflux activity in the bacteria reduces the inhibitory activity of the plant extracts. The inhibition of bacterial growth was measured using a Kirby-Bauer disc diffusion assay. The diameter of the zone of growth inhibition surrounding discs treated with plant extracts was used as the measure of the anti-bacterial activity of the extracts against each bacterial species. Our results showed that 1.25 mg of T. lanatum extract inhibits the growth of gram-positive bacteria but not gram-negative bacteria. However, growth of the E. coli ΔtolC mutant was inhibited by 1.25 mg of T. lanatum extract, suggesting that the resistance of gram-negative bacteria to the anti-bacterial activity of T. lanatum may be due the drug-efflux ability of some of these bacterial species

The Avengers Disassembled: Deconstructing Gender & Hegemonic Masculinity in Superhero Culture

This study explores the construction of gender and manifestation of hegemonic masculinity in comic and superhero culture. It is an investigation into the marginalization and discrimination of “lesser” masculinities that do not conform to the ideals of hegemony as theorized by R.W. Connell. Employing a third-­‐wave feminist and masculinity theorist approach to gender and sexuality theory, this study considers the massive expansion of comic culture from the early 1940s through the early twenty-­‐first century, and the many ways in which gender and sexuality have been constructed in these narratives. The research illustrates the gross injustice of an idealized version of masculinity that rewards hierarchical structures and male superiority, embraces competition and aggression, and celebrates the domination of weaker individuals through power and violence. Evidence suggests that the continual exposure and consumption of popular culture has the potential to influence social and cultural thought. Through a qualitative film analysis of Joss Whedon’s The Avengers (2012), this research project critiques the various ways in which certain masculinities are more socially privileged than others, and how those that do not fulfill expected gender norms are often relegated to villainy, or—like most women in comic culture—submissive or support roles. As such, this project demonstrates the possibilities of social justice interventions into pop culture masculinity by proposing alternative paths to healthy masculinities that are not marginalizing, discriminatory, or oppressive in nature, thereby disproving the myths of manhood that suggest there is only one way to be a “real” man

Identity and Identification: Femininity on Hadrian's Wall

The archaeological record has failed to acknowledge the contribution of women in the male dominated spaces of Roman military sites. Recent studies have helped to uncover the most accurate socio-spatial account of the gendered nature of Roman forts in Britain. This thesis focuses on the presence of women in the region of Hadrian’s Wall, and in particular, at the forts of Housesteads and Vindolanda while they were occupied by the Roman military (c. AD 122/4-410 and c. AD 85-400 respectively). Textual, skeletal, and artefactual evidence from both sites provide the basis qualitative and quantitative analyses drawing upon a total of 789 artefacts (150 from Housesteads and 639 from Vindolanda) within the artefact catalogue. This evidence is used to idenitfy the socio-spatial distribution of women at both sites as well as what can be said about the lives of the women present there. By collating different strands of evidence and creating a more holistic approach to the analysis of the presence of women, this thesis supplements the existing archaeological discourse of Housesteads and Vindolanda as well as the wider subject area of gender in Roman military sites. The findings of this study include, first, the presence of women of different socio-economic status at these two sites within both the extramural settlements and the forts themselves. Second, through the 3rd into the 4th century AD there was an increase in the evidence associated with the presence of women within the forts of Housesteads and Vindolanda. Third, the possibility that the increase in evidence was not necessarily a result of an increase in the presence of women, but rather it reflects the lack of meticulous clear up immediately preceding abandonment of the sites. Fourth, this thesis has highlighted the need for further excavation at Housesteads

Petroleum hydrocarbon content, leaching and degradation from surficial bitumens in the Athabasca oil sands region

Mine reclamation has become a topic of considerable research in the Athabasca Oil Sands Region of Northeastern Alberta, Canada. In this area some of the largest open pit mines in the world extract bitumen, a type of heavy oil, from the oil bearing McMurray Formation. At the close of mine operations, lease holders are required to return the land to equivalent capability. To achieve this, several existing waste piles will need to be capped and a functioning ecosystem re-established. Proposed borrow pits for capping material were recently found to contain reworked bitumen materials of various shapes and sizes. This reworked bitumen has been named tarballs by local industry. The use of that name is maintained throughout this study. The tarball accumulations are very abundant in some areas but also occur infrequently in apparently clean areas. In this study, the petroleum hydrocarbon signature and leaching characteristics of the tarballs were determined. The hydrocarbon content and composition of the tarballs were assessed using the Canadian Council of Ministers of the Environment (CCME) methods. The data were presented in terms of the four CCME fractions. Leaching characteristics were determined using a custom designed, unsaturated soil column experiment carried out at the University of Saskatchewan. The soil column was monitored for petroleum hydrocarbons, total carbon and total organic carbon in leachate water and soil respiration as a surrogate for biodegradation. The bitumen was found to consist primarily of heavy hydrocarbons, CCME Fractions 3 and 4, at levels of thousands and tens of thousands of mg/kg respectively. Gravimetric analyses indicated that a significant proportion of the tarball materials are very heavy hydrocarbons beyond the range of high temperature gas chromatography. These very heavy hydrocarbons are greater than carbon number C90. Lighter and more mobile hydrocarbons were occasionally identified at the core of larger accumulations. Where identified, the lighter fractions were typically accompanied by F3 and F4 hydrocarbons at one to two orders of magnitude greater than typical tarball material. Leachate was found to contain F2 hydrocarbons at less than 0.2 mg/L, a small fraction of the CCME clean water guideline of 1.1 mg/L. F3 hydrocarbons were identified at levels up to 0.6 mg/L. Soil respiration indicated a very low activity system, suggesting limited potential for biodegradation. Tarball materials are concluded to be of little concern for potential impacts to groundwater based upon the hydrocarbon fingerprint and the observed leaching characteristics of the tarball materials

An Ethnobotanical approach to finding antimicrobial compounds in wooly blue curls (Trichostema lanatum) using a Kirby-Bauer disc diffusion assay

Plants can be an important source of creativity and production of new drugs. In this study, extracts of wooly blue curls (Trichostema lanatum) were made using DMSO and tested for antimicrobial activity on a panel of bacteria commonly found in separate ecological niches. Wooly blue curls (WBC) was chosen due to its being recorded as a strong disinfectant by the Chumash people. It was found that WBC does exhibit antimicrobial activity against gram positive bacteria and not against gram negative bacteria. However, gram negative bacteria with reduced drug efflux function became susceptible to the WBC extract

Circumferential guided wave EMAT system for pipeline screening using shear horizontal ultrasound

The use of guided waves is now widespread in industrial NDT for locating metal loss in pipelines, that manifests as pitting, corrosion and general wall thinning. In this paper, a screening technique is assessed in terms of defect detection and defect sizing capability. Shear Horizontal (SH) guided waves propagate circumferentially around the pipe whilst the scanner is moved axially along the length. This type of tool is preferable to other methods, being applied to the exterior of the pipe, without requiring full circumferential access, and is able to operate through thin coatings (up to 1 mm thick). It is designed to provide a pipe screening tool for petrochemical pipelines both topside and subsea, particularly for detecting defects at pipe support areas. The system's efficacy in terms of detection and sizing of defects is considered via experimental measurements on artificially induced defects and in service corrosion patches, with results compared to finite element modelling of the interaction of the guided waves with artificial defects. Finite element modelling has been used to better understand the behaviour of different wave modes when they interact with defects, focusing on the mode conversions and reflections that occur

Effect of Ambient Air Temperature on Leaf Size in Raphanus sativus

Global warming is an increasing problem in today’s society. Thus, it is important to know how plants, specifically those that are cultivated for human consumption, react to rising average temperatures. This experiment tested how the leaf size of a common crop plant, Raphanus sativus (radish), is affected by two different temperatures. It is hypothesized that as temperature rises, the leaf size will increase, giving the leaf greater ability to cool via transpiration because of an larger surface area for stomatal conductance. This hypothesis was tested by growing two samples of plants in separate incubators. One sample was grown at a normal atmospheric temperature, and the other at a temperature 6 degrees Celsius higher. The average leaf area of each sample was measured using the Leaf Area Meter. Comparing the average leaf sizes of the group of radishes grown in warmer versus cooler temperatures showed a significant increase in both growth rates and final leaf sizes for the plants grown in the warmer incubator. Therefore, radishes clearly show phenotypic plasticity of their leaf sizes in response to changing temperatures. This morphological adaptation may increase the plant’s physiological fitness in its new environment, giving hope that common crop plants can make some adaptations to the world’s changing climate, mitigating some of the negative effects of global warming for those who rely on such crops for subsistence