Veterinary and forensic entomology: the association of blow flies and flesh flies with living and dead vertebrate tissues

The 21 papers presented in this thesis are representative of the candidate’s research output over a 27-year period in the field s of veterinary and forensic entomology and include some of his most significant contributions from >150 post-doctoral peer-reviewed publications. They include scholarly, synoptic reviews and novel experimental research in a wide variety of areas, ranging from taxonomy and systematics to ecology, physiolog y, behaviour and control techniques and show how these areas impact and interact with the overarching theme of the thesis, the association of blow flies and flesh flies with living and dead vertebrate tissues. Studies of flies on living vertebrate tissues are linked to the disease condition known as myiasis, in the field of veterinary entomology, while studies of flies on dead tissues relate to the field of forensic entomology, the interpretation of insect evidence in legal investigations. The work presented in the thesis has helped to significantly advance veterinary and forensic entomology by:- • Providing the necessary knowledge base for the advancement of research on myiasis, especially traumatic myiasis a hitherto neglected tropical disease, and the most important obligate myiasis -causing species, thereby improving our ability to respond to future range expansions of these economically important pests in a timely manner. • Improving techniques for trapping myiasis-causing flies for monitoring and control. • Improving techniques for prophylactic treatment of sheep/goat flocks against agents of traumatic myiasis. • Improving our understanding of the genetic make-up of geographically dispersed populations of the two most important agents of traumatic myiasis in the Old World, Chrysomya bezziana and Wohlfahrtia magnifica. • Providing protocols and raising standards for the application of forensic entomology. • Improving methods for collection, preservation, identification and aging of fly samples in forensic entomology. • Introducing the use of micro-computed tomography techniques to provide novel qualitative and quantitative information on the intra- puparial development of blow flies for use in forensic entomology and studies of metamorphosis. The candidate has developed w orld-class expertise in myiasis and forensic entomology and the application of both fields to matters of societal importance, pest control and the judicial system. The impact of the published works is demonstrated by:- • The significant and increasing citation levels over the period considered. • The stimulation of studies by other researchers globally in the two fields. • The inclusion of the knowledge and techniques into standard international protocols and manuals on myiasis and forensic entomology. The paper s presented here in support of this submission to the Doctor of Science Degree provide evidence of a sustained and significant contribution by the candidate to the fields of veterinary and forensic entomology, with impact at an international level

Mutual antagonism of target of rapamycin and calcineurin signaling

Growth and stress are generally incompatible states. Stressed cells adapt to an insult by restraining growth, and conversely, growing cells keep stress responses at bay. This is evident in many physiological settings, including for example, the effect of stress on the immune or nervous system, but the underlying signaling mechanisms mediating such mutual antagonism are poorly understood. In eukaryotes, a central activator of cell growth is the protein kinase target of rapamycin (TOR) and its namesake signaling network. Calcineurin is a conserved, Ca(2+)/calmodulin-dependent protein phosphatase and target of the immunosuppressant FK506 (tacrolimus) that is activated in yeast during stress to promote cell survival. Here we show yeast mutants defective for TOR complex 2 (TORC2) or the essential homologous TORC2 effectors, SLM1 and SLM2, exhibited constitutive activation of calcineurin-dependent transcription and actin depolarization. Conversely, cells defective in calcineurin exhibited SLM1 hyperphosphorylation and enhanced interaction between TORC2 and SLM1. Furthermore, a mutant SLM1 protein (SLM1(DeltaC14)) lacking a sequence related to the consensus calcineurin docking site (PxIxIT) was insensitive to calcineurin, and SLM1(Delta)(C14) slm2 mutant cells were hypersensitive to oxidative stress. Thus, TORC2-SLM signaling negatively regulates calcineurin, and calcineurin negatively regulates TORC2-SLM. These findings provide a molecular basis for the mutual antagonism of growth and stress

Early Elemental and Ionic Changes in Cultured Cells After Stimulation with Epidermal Growth Factor

Stimulation of A43 l cells (a human vulval epidermal cell line) with 50 ng/ml of epidermal growth factor (EGF) in the presence of 1. 7 mM extracellular calcium produced a sharp and sustained rise in intracellular ionic Ca2+, increased elemental Na, decreased K and a rise in Ca. In the absence of extracellular calcium, the initial Ca2+ rise remained but the sustained elevation of intracellular Ca2+ was abolished, Na and K fluxes were variable and the Ca did not change. Increased Na and decreased K was marked at 2 minutes and returned to the control value after 60 minutes. The increase in Ca was an early event. Cells stimulated with EGF showed a pronounced morphological disruption, especially the mitochondria. The response of NR6/SA3 and NR6/DC7 cells (genetically engineered rodent fibroblast cell lines) to EGF stimulation was higher than that of the A431 cells, as was the resting cytoplasmic Ca2+. Untreated NR6/SA3 and NR6/DC7 cells possessed an increased Na/K ratio when compared with A431 cells

Yellotas: A Unique Yellow Serradella Cultivar With Potential for Permanent Pasture Environments

Yellow serradella (Ornithopus compressus L.) has been identified as a priority self-regenerating annual legume species for permanent pasture environments in south-eastern Australia. However, most yellow serradella genotypes exhibit high levels of hard seed and slow rates of hard seed breakdown, which reduces regeneration density in the years following the year of sowing . One cultivar, Yellotas, exhibits a much faster rate of hard seed breakdown and has been identified as one of only a handful of cultivars of that species with promising persistence in permanent pasture environments. In addition, this cultivar is substantially easier to de-hull than other cultivars of that species, potentially reducing seed costs. In a field evaluation under severe drought conditions, this cultivar was shown to exhibit a high level of tolerance to close grazing. Yet, doubt still exists as to whether cv. Yellotas produces sufficient residual hard seed to withstand periodic drought suggesting further improvement may be required. This paper details the origins of cultivar and observations of its performance under a range of conditions in south-eastern Australia

N-Functionalised TsDPEN catalysts for asymmetric transfer hydrogenation; synthesis and applications

A series of Ru(II)/arene complexes containing N-alkylated derivatives of TsDPEN were prepared and tested in the asymmetric transfer hydrogenation (ATH) of ketones. The results demonstrated that a wide variety of functionality were tolerated on the basic amine of the TsDPEN ligand, without significantly disrupting the ability of the catalyst to catalyse hydrogen transfer reactions

Unification Picture in Minimal Supersymmetric SU(5) Model with String Remnants

The significant heavy threshold effect is found in the supersymmetric SU(5) model with two adjoint scalars, one of which is interpreted as a massive string mode decoupled from the lower-energy particle spectra. This threshold related with the generic mass splitting of the basic adjoint moduli is shown to alter properly the running of gauge couplings, thus giving a natural solution to the string-scale grand unification as prescribed at low energies by LEP precision measurements and minimal particle content. The further symmetry condition of the (top-bottom) Yukawa and gauge coupling superunification at a string scale results in the perfectly working predictions for the top and bottom quark masses in the absence of any large supersymmetric threshold corrections.Comment: published versio

Structure and magnetism of the skyrmion hosting family GaV4S8−ySey with low levels of substitutions between 0≤y≤0.5 and 7.5≤y≤8

Polycrystalline members of the GaV4S8−ySey family of materials with small levels of substitution between 0 ≤ y ≤ 0.5 and 7.5 ≤ y ≤ 8 have been synthesized in order to investigate their magnetic and structural properties. Substitutions to the skyrmion hosting parent compounds GaV4S8 and GaV4Se8 are found to suppress the temperature of the cubic-to-rhombohedral structural phase transition that occurs in both end compounds and to create a temperature region around the transition where there is a coexistence of these two phases. Similarly, the magnitude of the magnetization and temperature of the magnetic transition are both suppressed in all substituted compounds until a glassy-like magnetic state is realized. There is evidence from the ac susceptibility data that skyrmion lattices with similar dynamics to those in GaV4S8 and GaV4Se8 are present in compounds with very low levels of substitution, 0 < y < 0.2 and 7.8 < y < 8, however, these states vanish at higher levels of substitution. The magnetic properties of these substituted materials are affected by the substitution altering exchange pathways and resulting in the creation of increasingly disordered magnetic states

Measurement of gut permeability using fluorescent tracer agent technology

Abstract The healthy gut restricts macromolecular and bacterial movement across tight junctions, while increased intestinal permeability accompanies many intestinal disorders. Dual sugar absorption tests, which measure intestinal permeability in humans, present challenges. Therefore, we asked if enterally administered fluorescent tracers could ascertain mucosal integrity, because transcutaneous measurement of differentially absorbed molecules could enable specimen-free evaluation of permeability. We induced small bowel injury in rats using high- (15 mg/kg), intermediate- (10 mg/kg), and low- (5 mg/kg) dose indomethacin. Then, we compared urinary ratios of enterally administered fluorescent tracers MB-402 and MB-301 to urinary ratios of sugar tracers lactulose and rhamnose. We also tested the ability of transcutaneous sensors to measure the ratios of absorbed fluorophores. Urinary fluorophore and sugar ratios reflect gut injury in an indomethacin dose dependent manner. The fluorophores generated smooth curvilinear ratio trajectories with wide dynamic ranges. The more chaotic sugar ratios had narrower dynamic ranges. Fluorophore ratios measured through the skin distinguished indomethacin-challenged from same day control rats. Enterally administered fluorophores can identify intestinal injury in a rat model. Fluorophore ratios are measureable through the skin, obviating drawbacks of dual sugar absorption tests. Pending validation, this technology should be considered for human use

Yukawa Unification and the Superpartner Mass Scale

Naturalness in supersymmetry (SUSY) is under siege by increasingly stringent LHC constraints, but natural electroweak symmetry breaking still remains the most powerful motivation for superpartner masses within experimental reach. If naturalness is the wrong criterion then what determines the mass scale of the superpartners? We motivate supersymmetry by (1) gauge coupling unification, (2) dark matter, and (3) precision b-tau Yukawa unification. We show that for an LSP that is a bino-Higgsino admixture, these three requirements lead to an upper-bound on the stop and sbottom masses in the several TeV regime because the threshold correction to the bottom mass at the superpartner scale is required to have a particular size. For tan beta about 50, which is needed for t-b-tau unification, the stops must be lighter than 2.8 TeV when A_t has the opposite sign of the gluino mass, as is favored by renormalization group scaling. For lower values of tan beta, the top and bottom squarks must be even lighter. Yukawa unification plus dark matter implies that superpartners are likely in reach of the LHC, after the upgrade to 14 (or 13) TeV, independent of any considerations of naturalness. We present a model-independent, bottom-up analysis of the SUSY parameter space that is simultaneously consistent with Yukawa unification and the hint for m_h = 125 GeV. We study the flavor and dark matter phenomenology that accompanies this Yukawa unification. A large portion of the parameter space predicts that the branching fraction for B_s to mu^+ mu^- will be observed to be significantly lower than the SM value.Comment: 34 pages plus appendices, 20 figure