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Objectives: Synthetic adrenocorticotropic hormone or tetracosactide is routinely used in the diagnosis of hypoadrenocorticism and frequently in the diagnosis and treatment of hyperadrenocorticism. There have been repeated shortages of tetracosactide in recent years in Australia. This study investigated the agreement of serum cortisol after a compounded tetracosactide (Bova Aus), compared to commercial tetracosactide (Synacthen®) in healthy dogs. Methods: Prospective crossover study using 20 dogs. Ten dogs received 5 μg/kg Synacthen® on day 1 and 5 μg/kg compounded tetracosactide on Day 2. The other 10 dogs received the reverse order. Cortisol concentrations in each dog 1 h after injection were compared for agreement, which was defined as the limits of agreement of the Bland–Altman ratio to be within a range of 0.8–1.25. Passing‐Bablok regression analysis examined for constant and proportional biases. Results: Three dogs were excluded with post‐stimulation serum cortisol concentrations markedly outside reference interval. For the remaining 17 dogs, Bland–Altman ratio analysis of cortisol concentration (tetracosactide/Synacthen®) at 1 h found virtually no constant bias (mean of ratios 1.01;95% CI 0.97–1.05) and 95% limits of agreement were 0.88 (95% CI 0.78–0.90) and 1.17 (95% CI 1.13–1.25). This met our criteria for agreement between cortisol concentrations. Bias of the Bland–Altman difference was 2.8 nmol/L (95% CI −7.2 to 12.8); 95% limits of agreement −35.2 nmol/L (95% CI −57.0 to −26.1) and 40.8 nmol/L (95% CI 31.7–62.6). Passing‐Bablok regression analysis did not identify bias. Conclusion: In healthy dogs, cortisol concentrations were in agreement after compounded tetracosactide compared to commercial tetracosactide, Synacthen®. [ABSTRACT FROM AUTHOR]

This paper describes the mathematical formulation and modelling issues of a computational fluid dynamics (CFD) model of a 375 MW utility furnace. This tangentially-fired furnace is fuelled by high moisture content brown coal from coal mines at Latrobe Valley in Victoria, Australia. The influences of different turbulence models, particle dispersion, and radiation models on the CFD prediction are investigated. Two turbulence models, standard k-ε model and Shear-Stress Transport (SST) model, provide similar predictions that are in good agreement with the plant data. The effect of particle dispersion on the prediction is found to be insignificant for this high-volatile brown coal. The predicted wall incident radiation flux based on two radiation models, namely, discrete transfer (DT) model and P-1 model are compared against power plant measurements. The comparison reveals that the DT model provides good prediction of the radiation profiles, while the P-1 model considerably underpredicts the wall incident radiation flux. [ABSTRACT FROM AUTHOR]

Abstract: In a typical coal-fired power station boiler the ignition and the combustion of the fuel is largely controlled by burner aerodynamics. An experimental and numerical study of the rectangular slot-burners widely used on power stations in Victoria, Australia has been conducted to improve understanding of jet development within the boiler. The 1:15 scale model burner consisted of a central (primary) rectangular fuel nozzle with two (secondary) rectangular air jets positioned above and below it. The burner jets entered the measurement vessel at an angle of 60° to the wall. A cross-flow jet was attached to the wall of the vessel to simulate the recirculation prevalent in power station boilers. Experiments were conducted using a primary to cross-flow jet velocity ratio (φ) of 1.0 and secondary to primary jet velocity ratios (ϕ) of 1.0 and 3.0. Laser Doppler Anemometry (LDA) was used to measure mean and turbulent velocity components in the near field and downstream regions of the jets. Cross-flow significantly influenced the near field flow development from the slot-burner by deviating both primary and secondary jets from their geometric axes towards the wall. The degree of deviation was greater for ϕ =1.0 since the higher velocity secondary jets increased the overall momentum of the primary jet for ϕ =3.0. A numerical investigation of the rectangular slot-burner was also performed. First, the numerical results were validated against the experimental results and then visualization of the developing flow field was used to reveal the finer details of the cross-flow/burner jet interaction. Agreement between numerical and experimental jet features was good, although the numerical results predicted a primary jet that was marginally too narrow. Also the predicted downstream behaviour for ϕ =3.0 deviated more significantly from experimental observation. Using the SST turbulence model, the numerical results suggested that a twin vortex was generated behind the initial region of the primary jet and this would aid in mixing of gas and fuel between primary and secondary jets. [Copyright &y& Elsevier]