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Mating weight and condition score are both good predictors of lambing potential for young Merino and Border Leicester Merino ewes across different environments and years in Australia
Get PDFContext: Increasing mating weight or condition score increases the lambing potential of ewes (fetuses scanned per 100 ewes joined).
Aim: We hypothesised that in some years, condition score would contribute an additional effect to mating weight on lambing potential.
Methods: Border Leicester Merino and Merino ewes were mated naturally to Merino or Terminal rams between 2008 and 2013 at eight linked sites across Australia. Border Leicester Merino ewes were mated in their first year while Merino ewes were not mated until their second year. All ewes were mated for a second time as 2 year olds (Border Leicester Merinos) or 3 year olds (Merino). A total of 4270 Border Leicester Merino and 5788 Merino ewes were weighed and condition scored at mating and scanned for pregnancy.
Key results: Lambing potential increased by 3.1% per 1 kg increase in mating weight, compared to 1.3% for 1 and 2 year old Border Leicester Merinos respectively, and by 2.1% compared to 1.4% for 2 and 3 year old Merinos respectively (P < 0.05). Lambing potential increased by 27% compared to 13% per increase in condition score for 1 and 2 year old Border Leicester Merinos respectively, and by 29% compared to 25% for for 2 and 3 year old Merinos respectively (P < 0.05). All relationships were linear. When both mating weight and condition score were fitted together, mating condition score explained additional variation to weight in one instance of all the 160 possible breed (n = 2) × age (n = 2) × site (n = 8) × mating year (n = 5) combinations.
Conclusions: Mating weight and condition score increased the lambing potential of ewes linearly with differences due to ewe age, year and possibly ewe breed. Mating condition score rarely explained additional variation in lambing potential to weight in young Merino or Border Leicester Merino ewes.
Implications: If ewes are weighed at mating then condition scoring is of minimal extra benefit to predict lambing potential. Achieving the heaviest possible mating weights or highest condition score maximises the lambing potential of ewes in their first two mating years
‘Never be yourself, yet always: Writing a first-person moving beyond self’
No full textIn this thesis I critically and creatively explore the potential for first-person writing that, rather than being limited to its subject position, is capable of expansiveness, or a movement beyond its apparent position. Beginning as a study of Virginia Woolf’s The Waves (1931), the thesis brings Woolf’s work into conversation with Roland Barthes’ lectures on haiku in The Preparation of the Novel (2011) and Brian Dillon’s Essayism (2017). I will show how The Waves might be read as essayistic, broadly, in that it is speculative, contains partial accounts, highlights contingent experience, and privileges uncertainty. More specifically, The Waves can be read as essayistic in that Woolf’s use of ‘I’ is – like the ‘I’ of her essays – a mixture of personal and impersonal, capable of a situatedness, and a movement beyond. The thesis combines theoretical discussion with close readings of fragments from The Waves. Through the thesis I relate the notion of a first-person moving beyond self to my interest in the role of impersonality in artistic creation. I argue that in the artistic process, one must inhabit that paradoxical position Woolf calls for in an essay-writer, ‘never to be yourself and yet always’. The journey towards the art of creation begins from the personal, but necessarily involves an openness to uncertainty. Following the critical component of this thesis is a novel in which I write in the first-person with a capacity for expansiveness, or movement towards the impersonal
Predators in a mining landscape: Threats to a behaviourally unique, endangered lizard
Get PDFPatchy resource distribution can cluster predator activity around areas of the highest productivity in ecosystems. For the endangered Western Spiny-tailed Skink (Egernia stokesii badia) in Western Australia, the log piles that they permanently inhabit in an otherwise patchy, arid landscape, represent a potentially reliable, high abundance food source for predators. Not only are encounter rates by potential predators of E. s. badia likely to be influenced by vegetation structure at the microhabitat scale but also E. s. badia occurs in a region where mine sites and associated infrastructure, such as landfill sites, likely concentrate generalist predators (e.g. Feral Cats and corvids). We assessed the influence of the presence of coarse woody debris (CWD) and distance to the landfill on predator behaviour towards E. s. badia through plasticine model experiments, unbounded point count bird surveys and camera trapping. We found that CWD inhabited by E. s. badia attracted a greater relative activity of corvids compared with uninhabited CWD, or control sites without CWD. The relative activity of corvids and predatory birds combined increased with decreasing distance from the landfill. Preferential hunting by corvids at CWD inhabited by E. s. badia compared to both uninhabited CWD and open sites suggests that inhabited CWD may be targeted by generalist predators in the region, and that adaptive management may be required for species conservation around active mining areas
Dopant interaction in binary metal oxide system: Towards the development of an improved supercapacitor material
Get PDFTechnological advancement has raised the expectation on the role of energy storage systems. With the transition towards renewable technologies like solar and wind, demand for efficient energy storage systems capable of harvesting energy from various sources and delivering stable electricity output to meet customers' demand is in priority. Supercapacitors (SCs) are complementary to battery technology. However, SCs can provide high power density, longer life cycle, and superior round-trip efficiency compared to battery systems. Hence, it holds an important space in energy storage technology. This thesis presents a series of modified materials of binary metal oxides (BMOs) family and biomass-derived activated carbon detailing material synthesis and the strategies to improve its performance, optimization, and performance testing for supercapacitor applications.
A new insight into existing knowledge in BMOs having a structural formula ABOx to improve energy storage capacity by introducing dopants is presented in this thesis. Doping introduces impurities in a pristine material that alters its physical and chemical properties. Detailed experimental findings along with vital theoretical validations on ABOx crystal structure (where A and B represents a wide range of cation and anion metal ion site such as Ni, Co, Mg, Bi, Mo, etc., O represents oxygen and x = 1, 2, 3, etc. in a BMO family) for both anode and cathode material is presented. A detailed electrochemical characterization is presented by cyclic voltammetry and charge/discharge to quantify its capacitance value, energy and power densities, and cyclic stability in an aqueous alkaline medium. The investigated materials are physically characterized using various techniques. The change in morphology of BMOs resulting from the synthesis procedure or dopant additive is visualized by field-emission scanning electron microscopy (FE-SEM). The ABOx crystal structure has been validated via X-ray diffraction (XRD), which has also been used as a primary component for theoretical validation. A surface-sensitive technique, X-ray photoelectron spectroscopy (XPS), has been used to identify the elemental composition (Ni, Co, Mg, Bi, Mo, O, etc. and its chemical state. Change in the functional group is studied by infra-red spectroscopy (IR) along with synchrotron sourced radiation.
In a cathode material, nickel molybdate (NiMoO4), 0.2 wt% of zinc (Zn) dopant improved the electrochemical performance by 15% compared to the pristine material. Computational study (density functional theory, DFT) showed that the optimal Zn doped NiMoO4 (ZNM) resulted in a thermodynamically stable structure with an excess of oxygen vacancy, hence enhancing the charge transport between the electrode surface and OH− ion of the NaOH electrolyte, which agrees with the experimental finding. In the subsequent chapter, Bismuth-based BMO, bismuth molybdate (Bi2MoO6), a highly redox-active system, is chemically tuned using Gadolinium (Gd) as a dopant for anode material. Gd dopant (0.05 wt.%) stabilized the structure as it is energetically favourable while enhancing energy storage. Increase in areal capacitance value from 0.417 F cm−2 to 2.152 F cm−2 corresponding to Bi2MoO6 and Gd0.05Bi1.95MoO6 respectively was observed.
Further down towards my Ph.D. thesis, to tune the nanoparticle interfacial properties and its stability, a core@shell structure is studied. A synergistic effect of dopant along with a hierarchical core@shell structure exhibited enhanced and stable charge storage behaviour. ZNM as a core and cobalt tungstate (CoWO4, termed as CW) as a shell, i.e., ZNM@CW led to an improved faradic reaction contributing to efficient charge transfer. An alteration of the interfacial region explains this enhanced performance in core@shell nanocomposites, and the surface reconstruction is due to the core@shell combination. ZNM alone delivered an areal capacitance value of 2.40 F cm−2, whereas ZNM@CW showed superior performance with 7.12 F cm−2 energy storage capacity. When ZNM@CW is paired with commercial activated carbon (AC) as an asymmetric SC device, it retained 96% of its initial capacitance even after 1000 continuous charge-discharge cycles.
To understand the difference in electrochemical behaviour as a result of anion (B site) substitution in the ABOx system, molybdenum (Mo) has been replaced by tungsten (W) and reported in one of the chapters. Both Mo and W are electrochemically active materials and are widely used in energy storage, catalyst, and sensor technologies. Nickel molybdate (NiMoO4), compared to nickel tungstate (NiWO4), delivered enhanced electrochemical performance as a contribution from the faradic reaction between Ni2+ and Ni3+. Although a similar faradic reaction occurs in NiWO4, the formation of tungsten oxide (WO3) passivation layer occurs on the electrode surface due to the reaction of tungstate with the electrolyte, resulting in a decreased energy storage capacity. NiMoO4 vs. AC device exhibited discharge capacitance of 124 F g−1, whereas NiWO4 vs. AC device showed discharge capacitance of 77 F g−1. Regardless of the storage value, both the materials were fairly stable, capable of retaining 87.14% (NiMoO4) and 82.22% (NiWO4) even after a 1000 continuous charge-discharge cycle.
This thesis is concluded by exploring biomass-derived activated carbon as an efficient anode material. It is paired with an excellent Zn-doped NiMoO4 cathode material, both are synthesized in the laboratory. Wheat straw, an agricultural waste, is converted into a value-added product after chemical and physical treatments. Acid (H2SO4) activated wheat-straw (WS-acid) delivered a specific capacitance of 162 F g−1 in a one-electrode configuration. An asymmetric device, i.e., ZNM vs.WS-acid derived AC, delivered a specific capacitance of 118 F g−1. This device presents a similar energy storing ability to commercial activated carbon as described in the Zn-doped NiMoO4 chapter delivering specific capacitance of 122 F g−1. This opens a path for exploring a sustainable carbon source without any mining hazard. Coal, if used as a source of carbon, would require energy to dig out from the pit, which would also involve greenhouse gas emissions. Recommendations for further work are put forward in the conclusion chapter
Plants can access limited amounts of nitrogen- and sulphur-containing amino acids in soil owing to rapid microbial decomposition
No full textPurpose
Nitrogen (N) and sulphur (S) are essential for plant growth and development. Cysteine (Cys) and methionine (Met) are N- and S-containing amino acids in soils. However, it is unclear whether plants possess a strong ability to utilise N- and S-containing amino acids from the plant physiology perspective, and whether they can access amino acids when facing rapid microbial decomposition in the soil.
Methods
Wheat and oilseed rape were cultivated using a sterilised hydroponic solution in the laboratory and field conditions with 13C-, 14C-, 15N-, and 35S-labelled Cys and Met.
Results
With sterilised hydroponic cultivation, wheat and oilseed rape possessed a greater ability for Cys and Met uptake than for SO42− uptake, but these compounds did not support plant growth at high concentrations. The uptake rate of Cys and Met in oilseed rape was almost 20-fold higher than that in wheat, while the transportation ratio was even higher, indicating that oilseed rape not only possesses a great ability for S-containing amino acid uptake but also metabolises and transports them to the shoot quickly. A short-term labelling uptake test (6 h) in the field showed that 0.6–2.2% of total added Cys and Met were utilised by wheat and oilseed rape in the intact form owing to fierce competition from soil microorganisms.
Conclusions
Wheat and oilseed rape possess a great ability for Cys and Met uptake but can access limited amounts owing to rapid microbial decomposition in soil
Characteristics and outcomes of dog attacks to dogs and cats in Melbourne, Australia: A retrospective study of 459 cases (2018)
No full textDog-dog and dog-cat attacks can result in severe medical, financial, and emotional injury to pets and owners. The characteristics of dog-dog and dog-cat attack victims, the circumstances surrounding these attacks and the financial burden from veterinary visits is not reported in Australia. Medical records from 459 animals that were presented to the emergency service of four specialty hospitals in Melbourne, Australia in 2018 following a dog attack were assessed via univariate and multivariate methodologies with a retrospective case-control study design. Animals who had been attacked by a dog comprised 2.4% of the overall caseload at these four hospitals. Risk factors identified in dog-dog attack victims for presenting to a veterinary emergency hospital after being attacked were being cross-bred (OR = 1.4, p = 0.014, 95% CI = 1.07–1.84) and neutered (OR = 1.4, p = 0.035, 95% CI = 1.03–2.00). Being aged > 2–7years was protective (OR = 0.70, p = 0.010, CI = 0.48–0.88). Dogs from houses with a lower Socio-economic Indices for Areas score (SIEFA) were more likely to be attacked at home by a known attacker, compared to those from houses with a higher SIEFA score who were more likely to be attacked in public by a dog unknown to them (p = <0.001). Cats who presented following a dog attack had a 46.3% survival to discharge, compared to 91.8% in dogs (p < 0.001). Final cost of treatment for dogs and cats was similar (median AU 360, respectively). Further research is needed to evaluate the population of dogs and cats attacked by dogs, to inform and direct public education campaigns aimed at reducing their incidence and overall burdens
First evidence of Entamoeba parasites in Australian Wild Deer and assessment of transmission to cattle
Get PDFAustralian wild deer populations have significantly expanded in size and distribution in recent decades. Due to their role in pathogen transmission, these deer populations pose a biosecurity risk to the livestock industry. However, little is known about the infection status of wild deer in Australia. The intestinal parasite Entamoeba bovis has been previously detected in farm and wild ruminants worldwide, but its epidemiology and distribution in wild ruminants remain largely unexplored. To investigate this knowledge gap, faecal samples of wild deer and domestic cattle from south-eastern Australia were collected and analysed for the presence of Entamoeba spp. using PCR and phylogenetic analysis of the conserved 18S rRNA gene. E. bovis parasites were detected at high prevalence in cattle and wild deer hosts, and two distinct Entamoeba ribosomal lineages (RLs), RL1 and RL8, were identified in wild deer. Phylogenetic analysis further revealed the existance of a novel Entamoeba species in sambar deer and a novel Entamoeba RL in fallow deer. While we anticipated cross-species transmission of E. bovis between wild deer and cattle, the data generated in this study demonstrated transmission is yet to occur in Australia. Overall, this study has identified novel variants of Entamoeba and constitutes the first report of Entamoeba in fallow deer and sambar deer, expanding the host range of this parasite. Epidemiological investigations and continued surveillance of Entamoeba parasites in farm ruminants and wild animals will be required to evaluate pathogen emergence and transmission to livestock
Mobile phones are hazardous microbial platforms warranting robust public health and biosecurity protocols
Get PDFAdvancements in technology and communication have revolutionised the twenty-first century with the introduction of mobile phones and smartphones. These phones are known to be platforms harbouring microbes with recent research shedding light on the abundance and broad spectrum of organisms they harbour. Mobile phone use in the community and in professional sectors including health care settings is a potential source of microbial dissemination. To identify the diversity of microbial genetic signature present on mobile phones owned by hospital medical staff. Twenty-six mobile phones of health care staff were swabbed. DNA extraction for downstream next generation sequencing shotgun metagenomic microbial profiling was performed. Survey questionnaires were handed to the staff to collect information on mobile phone usage and users’ behaviours. Each of the 26 mobile phones of this study was contaminated with microbes with the detection of antibiotic resistance and virulent factors. Taken together the sum of microbes and genes added together across all 26 mobile phones totalised 11,163 organisms (5714 bacteria, 675 fungi, 93 protists, 228 viruses, 4453 bacteriophages) and 2096 genes coding for antibiotic resistance and virulent factors. The survey of medical staff showed that 46% (12/26) of the participants used their mobile phones in the bathroom. Mobile phones are vectors of microbes and can contribute to microbial dissemination and nosocomial diseases worldwide. As fomites, mobile phones that are not decontaminated may pose serious risks for public health and biosecurity
Repeated-sprint training in heat and hypoxia: Effect of exercise-to-rest ratio
No full textThe aim of this study was to investigate acute performance and physiological responses to the manipulation of exercise-to-rest ratio (E:R) during repeated-sprint hypoxic training (RSH) in hot conditions. Twelve male team-sport players completed two experimental sessions at a simulated altitude of ∼3000 m (FIO2 0.144), air temperature of 40°C and relative humidity of 50%. Exercise involved either 3×5×10-s (E:R1:2) or 3×10×5-s (E:R1:4) maximal cycling sprints interspersed with active recoveries at 120W (20-s between sprints, 2.5 and 5-min between sets for E:R1:2 and E:R1:4 respectively). Sessions were matched for overall sprint and total session duration (47.5-min). Peak and mean power output, and total work were greater in E:R1:4 than E:R1:2 (p 0.05).These results indicate E:R1:4 increased mechanical power output and core temperature compared to E:R1:2. Both protocols had different effects on measures of muscle oxygenation, with E:R1:2 generating greater muscle oxygen extraction and E:R1:4 producing more muscle oxygenation flux, which are both important signals for peripheral adaptation. We conclude that the E:R manipulation during RSH in the heat might be used to target different physiological and performance outcomes, with these findings forming a strong base for future mechanistic investigation
Celebrity activism
No full textIdentifying as an ‘activist’ is akin to saying ‘I am an artist’, in that it is a foundational identity..