Characterisation and isolation of gut bacterial communities from Queensland fruit fly (Bactrocera tryoni) across different environments to improve the sterile insect technique

The digestive tracts of pest fruit flies (Tephritidae: Diptera) contain a diverse range of bacteria. Since the 1980’s there has been increasing interest in the role of microbial symbionts in tephritid fruit fly performance, rising sharply in the past decade. The sterile insect technique (SIT) is an environmentally safe insect pest management method that has been implemented against several tephritids and other pest insects of economic significance. The efficacy of SIT relies upon sterile males outcompeting field males to copulate with field females, which then fail to reproduce, resulting in suppression of pest populations. Mass production and sterilisation by irradiation can adversely affect several male fly traits. SIT has also been developed and deployed for the control of Queensland fruit fly, Bactrocera tryoni (Froggatt), Australia’s most significant horticultural pest species. Research has shown that bacteria play an important role in tephritid biology, and some bacterial isolates can improve performance traits, including mating competitiveness. However, little is known about the application of symbiotic bacteria in enhancing tephritid performance in SIT operational programs, and this is particularly the case for B. tryoni. Symbiotic bacteria supplied to mass-reared fruit flies may help overcome some of these issues. However, the effects of tephritid ontogeny, sex, diet and irradiation on their microbiota are not well known. The aim of this PhD was to establish the diversity and abundance of bacterial symbionts in the gut of B. tryoni collected from different laboratory and field environments. Overall my research contributes to the wider research effort on the microbiota of tephritid pest fruit flies. Recent advances in sequencing technology have enabled more insights into the diversity and dynamics gut bacterial communities of insects and the roles they play in insect development. Gut bacteria have been demonstrated to improve the performance of tephritid fruit flies and thus are a promising target in improving the sterile insect technique used in tephritid fruit fly management

Extraterrestrial life science

This is the author accepted manuscript. The final version is available from the Royal Society of Biology via the link in this recor

Spectral evidence for a powerful compact jet from XTE J1118+480

We present observations of the X-ray transient XTE J1118+480 during its Low/Hard X-ray state outburst in 2000, at radio and sub-millimetre wavelengths with the VLA, Ryle Telescope, MERLIN and JCMT. The high-resolution MERLIN observations reveal all the radio emission (at 5 GHz) to come from a compact core with physical dimensions smaller than 65*d(kpc) AU. The combined radio data reveal a persistent and inverted radio spectrum, with spectral index \~+0.5. The source is also detected at 350 GHz, on an extrapolation of the radio spectrum. Flat or inverted radio spectra are now known to be typical of the Low/Hard X-ray state, and are believed to arise in synchrotron emission from a partially self-absorbed jet. Comparison of the radio and sub-millimetre data with reported near-infrared observations suggest that the synchrotron emission from the jet extends to the near-infrared, or possibly even optical regimes. In this case the ratio of jet power to total X-ray luminosity is likely to be P_J/L_X >> 0.01, depending on the radiative efficiency and relativistic Doppler factor of the jet. Based on these arguments we conclude that during the period of our observations XTE J1118+480 was producing a powerful outflow which extracted a large fraction of the total accretion power.Comment: Accepted for publication as a Letter in MNRA

MeerKAT HI line observations of the nearby interacting galaxy pair NGC 1512/1510

We present MeerKAT HI line observations of the nearby interacting galaxy pair NGC 1512/1510. The MeerKAT data yield high-fidelity image sets characterised by an excellent combination of high angular resolution (~20") and and sensitivity (~0.08 Msun/pc^2), thereby offering the most detailed view of this well-studied system's neutral atomic hydrogen content, especially the HI co-located with the optical components of the galaxies. The stellar bulge and bar of NGC 1512 are located within a central HI depression where surface densities fall below 1 Msun/pc^2, while the galaxy's starburst ring coincides with a well-defined HI annulus delimited by a surface density of 3 Msun/pc^2. In stark contrast, the star-bursting companion, NGC 1510, has its young stellar population precisely matched to the highest HI over-densities we measure (~12.5 Msun/pc^2). The improved quality of the MeerKAT data warrants the first detailed measurements of the lengths and masses of the system's tidally-induced HI arms. We measure the longest of the two prominent HI arms to extend over ~27 kpc and to contain more than 30% of the system's total HI mass. We quantitatively explore the spatial correlation between HI and far-ultraviolet flux over a large range of HI mass surface densities spanning the outer disk. The results indicate the system's HI content to play an important role in setting the pre-conditions required for wide-spread, high-mass star formation. This work serves as a demonstration of the remarkable efficiency and accuracy with which MeerKAT can image nearby systems in HI line emission.Comment: 12 pages, 11 figures. Submitted only to arXi

Autonomous systems thermographic NDT of composite structures

Transient thermography is a method used successfully in the evaluation of composite materials and aerospace structures. It has the capacity to deliver both qualitative and quantitative results about hidden defects or features in a composite structure. Aircraft must undergo routine maintenance – inspection to check for any critical damage and thus to ensure its safety. This work aims to address the challenge of NDT automated inspection and improve the defects’ detection by suggesting an autonomous thermographic imaging approach using a UAV (Unmanned Aerial Vehicle) active thermographic system. The concept of active thermography is discussed and presented in the inspection of aircraft CFRP panels along with the mission planning for aerial inspection using the UAV for real time inspection. Results indicate that the suggested approach could significantly reduce the inspection time, cost, and workload, whilst potentially increase the probability of detection of defects on aircraft composites

Application of NDT thermographic imaging of aerospace structures

This work aims to address the effectiveness and challenges of Non-Destructive Testing (NDT) inspection and improve the detection of defects without causing damage to the material or operator. It focuses on two types of NDT methods; pulsed thermography and vibrothermography. The paper also explores the possibility of performing automated aerial inspection using an unmanned aerial vehicle (UAV) provided with a thermographic imaging system. The concept of active thermography is discussed for inspecting aircraft CFRP panels along with the proposal for performing aerial inspection using the UAV for real time inspection. Static NDT results and the further UAV research indicate that the UAV inspection approach could significantly reduce the inspection time, cost, and workload, whilst potentially increasing the probability of detection

Caudal Vertebral Body Articular Surface Morphology Correlates with Functional Tail Use in Anthropoid Primates

Prehensile tails, capable of suspending the entire body weight of an animal, have evolved in parallel in New World monkeys (Platyrrhini): once in the Atelinae (Alouatta, Ateles, Brachyteles, Lagothrix), and once in the Cebinae (Cebus, Sapajus). Structurally, the prehensile tails of atelines and cebines share morphological features that distinguish them from non-prehensile tails, including longer proximal tail regions, well-developed hemal processes, robust caudal vertebrae resistant to higher torsional and bending stresses, and caudal musculature capable of producing higher contractile forces. The functional significance of shape variation in the articular surfaces of caudal vertebral bodies, however, is relatively less well understood. Given that tail use differs considerably among prehensile and non-prehensile anthropoids, it is reasonable to predict that caudal vertebral body articular surface area and shape will respond to use-specific patterns of mechanical loading. We examine the potential for intervertebral articular surface contour curvature and relative surface area to discriminate between prehensile- and nonprehensile-tailed platyrrhines and cercopithecoids. The proximal and distal intervertebral articular surfaces of the first (Ca1), transitional (TV) and longest (LV) caudal vertebrae were examined for individuals representing 10 anthropoid taxa with differential patterns of tail-use. Study results reveal significant morphological differences consistent with the functional demands of unique patterns of tail use for all vertebral elements sampled. Prehensile-tailed platyrrhines that more frequently use their tails in suspension (atelines) had significantly larger and more convex intervertebral articular surfaces than all nonprehensile-tailed anthropoids examined here, although the intervertebral articular surface contour curvatures of large, terrestrial cercopithecoids (i.e. Papio) converge on the ateline condition. Prehensile-tailed platyrrhines that more often use their tails in tripodal bracing postures (cebines) are morphologically intermediate between atelines and nonprehensile tailed anthropoids.The authors would like to thank Bill Stanley, the Field Museum and the University of Texas at Austin for access to specimens and curatorial assistance as well as the Louisville Zoo and Dr. Roy Burns for their generous donation of Lagothrix lagotricha cadavers. Thanks also to Matthew Tocheri for access to curve fitting software and technical guidance, John Kappelman for the use of his desktop laser scanner and Brett Nachman for technical assistance

How to Cross-Examine Opposing Experts

Accomplished Georgia Law alumni Kay Deming (J.D.\u2778) and Rick Deane (J.D.\u2777) addressed how one should cross-examine opposing experts