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A comparative study of parasites in captive and wild Tasmanian devils
No full textThesis by publication.Includes bibliographical references.1. Review: Parasites of the Tasmanian devil and the potential impact of conservation management -- 2. Molecular characterization of Cryptosporidium and Giardia from Tasmanian devils -- 3. Parasite diversity in the Tasmanian devil - a comparative study of wild and captive devils.Chapter 1. Review: Parasites of the Tasmanian devil and the potential impact of conservation Management. Chapter 1 consists of a literature review of Tasmanian devil parasites and the Save the Tasmanian Devil Program. The review outlines current and historical knowledge of parasites in the Tasmanian devil, and discusses ways in which conservation management may theoretically change hostparasite interactions, both generally and with detail specific to the Save the Tasmanian Devil Program. I reviewed the literature and wrote this chapter with feedback provided by Michelle Power, my supervisor, and Samantha Fox, our collaborator with the Save the Tasmanian Devil Program. Chapter 2. Molecular characterization of Cryptosporidium and Giardia from Tasmanian devils. Chapter 2 describes the molecular characterisation of Cryptosporidium and Giardia from captive and wild Tasmanian devils. Faecal samples were collected from wild and captive devils, DNA was extracted, PCRs targeting Cryptosporidium and Giardia were performed, and sequence analysis of PCR amplicons allowed parasite species identification. The findings are discussed in the context of current knowledge of Cryptosporidium and Giardia in other Australian marsupials. Faecal samples were collected by staff of the Save the Tasmanian Devil Program, Devil Ark, Healesville Sanctuary, Monarto Zoo, Taronga Zoo, and Western Plains Zoo. I participated in fieldwork and sample collection with the Save the Tasmanian Devil Program, performed all laboratory work, data analysis and statistics, and wrote the chapter with feedback from my supervisor, Michelle Power. Chapter 3. Parasite diversity in the Tasmanian devil - a comparative study of wild and captive devils. Chapter 3 investigates gastrointestinal parasite prevalence and diversity in the Tasmanian devil, and compares findings between wild and captive populations. Zinc sulfate faecal flotations and microscopy were used to identify gastrointestinal helminths and coccidia, and prevalence data on Cryptosporidium and Giardia from Chapter 2 were also analysed. Faecal samples were collected by staff of the Save the Tasmanian Devil Program, Devil Ark, Healesville Sanctuary, Monarto Zoo, Taronga Zoo, and Western Plains Zoo. I participated in fieldwork and sample collection with the Save the Tasmanian Devil Program, performed all laboratory work, data analysis and statistics, and wrote the chapter with feedback from my supervisor, Michelle Power.Mode of access: World wide web1 online resource (v, 70 pages) illustration
Non-invasive characterization of cardiovascular autonomic dysfunction in multiple sclerosis
No full textEmpirical thesis.Bibliography: pages 117-125.Chapter 1. Introduction and literature review -- Chapter 2. Review of cardiovascular autonomic testing -- Chapter 3. Methods -- Chapter 4. Results -- Chapter 5. Discussion.Multiple Sclerosis (MS) is associated with autonomic nervous system damaged. Reported cardiovascular autonomic dysfunction (CAD) prevalence in MS varies between studies. As CAD lowers quality of life and may contribute to sudden death in MS, early CAD detection may assist in treatment and in risk identification. A comprehensive suite of cardiovascular autonomic tests was applied to 53 MS patients and results associated with clinical markers of MS severity. CAD was identified through analysis of continuous electrocardiogram and non-invasive finger blood pressure recording during 5-minutes supine rest, short-term deep breathing, Valsalva manoeuvre, orthostatic challenge and isometric exercise. There was greater prevalence of sympathetic (58%) than parasympathetic impairment (34%). Total brain and spine lesions was correlated with dampened sympathetic response in Valsalva manoeuvre and orthostatic challenge. Age corrected score for sympathetic control showed deterioration with longer disease duration and/or treatment delay>10 years. Comparison of a subset of MS patients (n=23) with age and gender-matched controls showed diminished baroreceptor reflex in MS and impaired sympathetic function using frequency domain systolic blood pressure variability analysis, techniques novel to MS investigations. Findings presented in this thesis demonstrate high prevalence of CAD in MS that can be evaluated using a combination of standard and more novel analysis techniques.Mode of access: World wide web1 online resource (xiv, 150 pages) colour illustration
The Gudaga Research Program : a case Study in undertaking research with an urban Aboriginal community
No full textThis paper presents the Gudaga Research Program as a case study describing the practice principles used to implement a successful research partnership with an urban Aboriginal community in south-western Sydney. This is one of few papers that address research issues unique to working with urban Aboriginal communities, in which the Aboriginal culture of the community is not homogenous. The authors argue that the relationships between the researchers and key community members and research participants underpin the research success. Throughout, the authors show that ongoing processes to nurture and reaffirm these relationships are important and require ongoing investment. A proposed practice framework demonstrates the relationship between knowledge and understanding of Aboriginal history and culture, the underpinning values including trust, respect, and reciprocity, and shared skills and communication. Examples of how these were built into the research are provided. These are important skills that have application beyond the research process.13 page(s
Loss of BAP1 expression occurs frequently in intrahepatic cholangiocarcinoma
No full textBRCA1-associated protein 1 (BAP1) is a deubiquitinating enzyme that functions as a tumor suppressor gene. Double hit BAP1 inactivation has been reported in a range of tumor types, including intrahepatic cholangiocarcinoma (ICC), sometimes in association with germline mutation. We performed immunohistochemistry for BAP1 on a well-characterized cohort of 211 ICC patients undergoing surgical resection with curative intent at 3 institutions based in 3 different countries. The median age at diagnosis was 65 years (range, 36.5-86) and 108 (51%) were men. Negative staining for BAP1 (defined as completely absent nuclear staining in the presence of positive internal controls in nonneoplastic cells) occurred in 55 ICCs (26%). BAP1 loss predicted a strong trend toward improved median survival of 40.80 months (95% CI, 28.14-53.46) versus 24.87 months (95% CI, 18.73-31.01), P=0.059). In a multivariate model including age, sex, BAP1 status, tumor stage, tumor grade, lymphovascular invasion, and tumor size, female sex was associated with improved survival (hazard ratio [HR] 0.54; 95% CI, 0.34-0.85), while advanced tumor stage and lymphovascular invasion (HR 1.89; 95% CI, 1.09-3.28) correlated with decreased survival. In a multivariate analysis, high grade tumors were associated with BAP1 loss (odds ratio [OR] 3.32; 95% CI, 1.29-8.55), while lymphatic invasion was inversely associated with BAP1 loss (OR 0.36; 95% CI, 0.13-0.99). In conclusion, we observed a trend toward improved prognosis in ICC associated with absent expression of BAP1 and an association of BAP1 loss with higher histological grade and absent lymphatic invasion. Female sex was associated with improved survival while advanced tumor stage and lymphatic invasion were associated with decreased survival.8 page(s
Differential genotypic effects of sexual trait size on offspring mating success and viability
No full textIndicator models of sexual selection predict that females mating with the most ornamented males should produce offspring with enhanced expression of fitness-related traits, such as overall vigor and viability. Empirical support for this prediction, however, is limited. We quantified the effects of a heritable and condition-dependent secondary sexual trait on offspring performance traits in Drosophila bipectinata Duda (Diptera: Drosophilidae). Forty-eight genetic (isofemale) lines were extracted from a natural population, reared in a common environment, and characterized in terms of sex comb size. We measured pupal viability and adult mating success among the progeny of the 5 lines with the largest combs (high line category) and the 5 lines with the smallest combs (low line category). The high line category produced offspring that were significantly more viable than the low line category, and this advantage held across 2 developmental temperatures. In contrast, there was no effect of line category on male mating success, although at the individual-level, comb size was significantly positively correlated with mating success. Our results indicate that the relative size of the D. bipectinata sex comb taps genotypic properties that enhance offspring fitness in a trait-specific manner. Thus, distinct proximate mechanisms likely underlie relationships between secondary sexual trait expression and different performance traits in offspring, offering a possible explanation for inconsistent support for the existence of indirect benefits in sexual selection.8 page(s
Kumbicins A-D : bis-indolyl benzenoids and benzoquinones from an Australian soil fungus, Aspergillus kumbius
No full textA soil survey conducted in southern Queensland, Australia, identified a novel isolate belonging to the genus Aspergillus subgenus Circumdati section Circumdati, Aspergillus kumbius FRR6049. Cultivation and fractionation of secondary metabolites from A. kumbius revealed a unique chemotype comprising three new bis-indolyl benzenoids, kumbicins A-C, and a new bis-indolyl benzoquinone, kumbicin D, along with the previously reported compounds asterriquinol D dimethyl ether, petromurins C and D, aspochracin, its N-demethyl analogue JBIR-15, and neohydroxyaspergillic acid. The structures of kumbicins A-D were assigned by detailed spectroscopic analysis. Kumbicin C was found to inhibit the growth of mouse myeloma cells (IC₅₀ 0.74 μgmL⁻¹) and the Gram-positive bacterium Bacillus subtilis (MIC 1.6 μgmL⁻¹).9 page(s
Design and measurements of a tri-band one-dimensional electromagnetic bandgap resonator antenna
No full textThe authors utilise a one-dimensional (1D) stack of three identical unprinted dielectric slabs as a superstructure to design a novel yet simple tri-band electromagnetic bandgap resonator antenna (ERA). The design, inspired from classical single-band 1D ERAs, is conceived by creating two resonant defects in the superstructure configuration to make it suitable for tri-band and high gain operation. A prototype, fabricated using FR4 material, is tested with a waveguide-fed slot antenna at 10.3, 11.9 and 13.7 GHz with a frequency ratio of 1.33:1.16:1. The slot feeds the cavity simultaneously in the three frequency bands and provides good impedance matching in each frequency band. Peak measured gains of 14.3, 13.4 and 16.1 dBi and radiation efficiencies of 83, 85 and 85% are achieved in the lower, middle and higher frequency bands, respectively.5 page(s
Drone casino mimesis : telewarfare and civil militarization
No full textThis article stages an examination of the complex imbrication of contemporary civil society with war and militarized violence. I ground my investigation in the context of the increasing cooption of civil sites, practices and technologies by the United States military in order to facilitate their conduct of war and the manner in which drone warfare has now been seamlessly accommodated within major metropolitan cities such as Las Vegas, Nevada. In the context of the article, I coin and deploy the term civil militarization. Civil militarization articulates the colonizing of civilian sites, practices and technologies by the military; it names the conversion of such civilian technologies as video games and mobile phones into technologies of war; and it addresses the now quasi-seamless flow that telewarfare enables between military sites and the larger suburban grid and practices of everyday life. In examining drone kills in the context of Nellis Air Force Base, Las Vegas, I bring into focus a new military configuration that I term 'drone casino mimesis'.22 page(s
Universality of load balancing schemes on the diffusion scale
No full textWe consider a system of N parallel queues with identical exponential service rates and a single dispatcher where tasks arrive as a Poisson process. When a task arrives, the dispatcher always assigns it to an idle server, if there is any, and to a server with the shortest queue among d randomly selected servers otherwise (1 ≤ d ≤ N). This load balancing scheme subsumes the so-called join-the-idle queue policy (d=1) and the celebrated join-the-shortest queue policy (d=N) as two crucial special cases. We develop a stochastic coupling construction to obtain the diffusion limit of the queue process in the Halfin-Whitt heavy-traffic regime, and establish that it does not depend on the value of d, implying that assigning tasks to idle servers is sufficient for diffusion level optimality.14 page(s