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Focused cardiac ultrasound (FCU) training in critical care is restricted by availability of instructors. Supervised training may be substituted by self-directed learning with an ultrasound simulator guided by automated electronic learning, enabling scalability.We prospectively compared learning outcomes in novice critical care physicians after completion of a supervised one-and-a-half-day workshop model with a self-guided course utilizing a simulator over four weeks. Both groups had identical pre-workshop on-line learning (20h). Image quality scores were compared using FCU performed on humans without pathology. Interpretive knowledge was compared using 20MCQ tests.Of 161 eligible, 145 participants consented. Total Image quality scores were higher in the Simulator group (95.2% vs. 66.0%, P .001) and also higher for each view (all P .001). Interpretive knowledge was not different before (78.6% vs. 79.0%) and after practical training (74.7% vs. 76.1%) and at 3 months (81.0% vs. 77.0%, all P .1). Including purchase of the simulator and ultrasound equipment, the simulator course required lower direct costs (AUD$796 vs. $1724 per participant) and instructor time (0.5 vs.1.5 days) but similar participant time (2.8 vs. 3.0 days).Self-directed learning with ultrasound simulators may be a scalable alternative to conventional supervised teaching with human models.

With a trend towards a zero-carbon dioxide (CO2) tailpipe future, driven by legislation and societal factors, engine manufacturers globally are investigating the use of alternative fuels that can minimize or eliminate tailpipe CO2. Hydrogen (H2) has re-emerged as a viable alternative fuel for combustion engines, aided by its relative flexibility to operating condition resulting from a wide flammability range, and the diversity of H2 production sources. An increasing share of H2 production is accomplished through the use of renewable energy, providing improved well-to-tank / cradle to grave and total life-cycle CO2 budgets. H2 as a combustion fuel is exceptionally prone to abnormal combustion, e.g.

In an effort to reduce fuel consumption and lower emissions output, there is a growing need for high efficiency engines in power generation. Ultra-lean (λ > ∼1.6) combustion via air dilution is an enabling technology for achieving high efficiencies while simultaneously reducing emissions of nitrogen oxides (NOx). Jet ignition is a pre-chamber-based combustion system that enables ultra-lean operation beyond what is achievable with traditional spark ignition engines. In this paper, results and analyses related to the downspeeding of a 390cc, high efficiency low-output single cylinder jet ignition engine operating ultra-lean are presented. The engine was developed as part of the US Department of Energy’s Advanced Research Projects Agency–Energy (DOE ARPA-E) GENSETS program1. The purpose of the program is to develop technologies for use in high efficiency combined heat and power generator sets. Due to the intended application of power generation, optimization of the engine for a specific operating condition is critical. An efficiency loss breakdown based on the Thermodynamic First Law is used to analyze the interdependent trends of engine speed, brake power, and normalized air-fuel ratio, lambda, with the aim of optimizing these parameters for brake thermal efficiency. The general trends of efficiency loss pathways with enleanment are found to be relatively insensitive to speed and load although the magnitude of the loss pathways changes. As the relative importance of the efficiency loss pathways changes with operating condition, so too does the lambda at which peak brake thermal efficiency occurs. The “peak efficiency lambda” was found to be at its leanest at low speed and high power where the influence of heat transfer is greatest and mechanical losses are minimized.