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Spontaneous heating in the active goaf area during normal mining processes poses increased threats to mine productivity and safety, as evidenced in events induced by spontaneous combustion of coal. To control and mitigate this engineering problem, there is a need to gain critical knowledge of spontaneous combustion in the longwall goaf area, which can be achieved through a combination of field tests and numerical modeling. This paper introduces the spontaneous combustion management system widely used in Australia and presents Computational Fluid Dynamics (CFD) models for the simulation of gas flow dynamics in the goaf area, based on the site conditions of an underground coal mine where coal seam gas is predominantly comprised of carbon dioxide. The models were validated with gas monitoring data and used to conduct parametric studies for proactive goaf inertisation optimization. Qualitative and quantitative analysis of simulation results indicated that better goaf inertisation could be achieved when nitrogen was injected via cut-through at 250 m on the maingate (MG) side and surface boreholes at 100 m and 700 m on the tailgate (TG) side, with a total injection rate greater than 1750 1/s. The oxygen concentration on the MG and TG side dropped below 5% at distances of 120 m and 75 m behind the longwall face, with an oxidation zone area of 35375 m2, which was approximately one-third of the oxidation zone area of the scenario without inert gas injection. Simulation results help shed light on improving current goaf inertisation practices to effectively reduce the risk of heating in goaf areas and improve mining process safety based on Australian conditions and practices. [ABSTRACT FROM AUTHOR]

Background: We assessed replication and excretion of the live attenuated tetravalent dengue vaccine (CYD-TDV) into biological fluids following vaccination in dengue-naive adults in Australia.Methods: Vaccinal viremia/shedding was assessed in a subset of participants enrolled in a lot-to-lot consistency study; 95 participants received 3 subcutaneous doses of CYD-TDV from phase 2/3 lots of the vaccine, and 8 received placebo; doses were administered 6 months apart. Quantitative reverse-transcription polymerase chain reaction (qR-PCR) analysis was used to initially detect the yellow fever virus (YFV) core protein gene in the backbone of CYD-TDV in serum, saliva and urine, followed by serotype-specific qRT-PCR analysis of samples positive for YFV by qRT-PCR (lower limit of detection, 5.16 GEq/mL).Results: YFV viremia was detected by qRT-PCR in 69.5% of participants (66 of 95) who received CYD-TDV, mainly 6-14 days after injection 1. The serotypes detected were serotype 4 (in 68.2% of participants [45 of 95]), serotype 3 (in 19.7% [13 of 95]), and serotype 1 (in 12.1% [8 of 95]); serotype 2 was not detected. None of the placebo recipients had vaccinal viremia/shedding. No participants had detectable viral shedding into saliva at levels above the lower limit of quantitation. Two participants had low-level viral shedding (serotype 3) in urine (5.47 and 5.77 GEq/mL). None of the participants with viremia or shedding experienced concomitant fever.Conclusions: Low-level vaccinal viremia may occur following vaccination with CYD-TDV, but this is not associated with any symptom or adverse event.Clinical Trials Registration: NCT01134263. [ABSTRACT FROM AUTHOR]