Data-driven resuscitation training using pose estimation

BACKGROUND

Cardiopulmonary resuscitation (CPR) training improves CPR skills while heavily relying on feedback. The quality of feedback can vary between experts, indicating a need for data-driven feedback to support experts. The goal of this study was to investigate pose estimation, a motion detection technology, to assess individual and team CPR quality with the arm angle and chest-to-chest distance metrics.

METHODS

After mandatory basic life support training, 91 healthcare providers performed a simulated CPR scenario in teams. Their behaviour was simultaneously rated based on pose estimation and by experts. It was assessed if the arm was straight at the elbow, by calculating the mean arm angle, and how close the distance between the team members was during chest compressions, by calculating the chest-to-chest distance. Both pose estimation metrics were compared with the expert ratings.

RESULTS

The data-driven and expert-based ratings for the arm angle differed by 77.3%, and based on pose estimation, 13.2% of participants kept the arm straight. The chest-to-chest distance ratings by expert and by pose estimation differed by 20.7% and based on pose estimation 63.2% of participants were closer than 1 m to the team member performing compressions.

CONCLUSIONS

Pose estimation-based metrics assessed learners' arm angles in more detail and their chest-to-chest distance comparably to expert ratings. Pose estimation metrics can complement educators with additional objective detail and allow them to focus on other aspects of the simulated CPR training, increasing the training's success and the participants' CPR quality.

TRIAL REGISTRATION

Not applicable.

Characterization of the oxygenated intermediate of the thermophilic cytochrome P450 CYP119

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Crystallization and preliminary X-ray diffraction analysis of a cytochrome P450 (CYP119) from Sulfolobus solfataricus

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Characterization of a cytochrome P450 from the acidothermophilic archaea Sulfolobus solfataricus

We report the cloning, expression, purification, and molecular characterization of a cytochrome P450 (CYP119) from the thermophilic archaea Sulfolobus solfataricus. This protein displays an absorption spectra in the reduced, oxidized, and carbonyl adduct analogous to those of other P450 enzymes. We demonstrate that P450 (CYP119) exhibits remarkable thermo- and pressure stability, with a melting temperature 40 degrees higher than that of the extensively studied cytochrome P450cam (CYP101) and an optical spectra completely resistant to the formation of the inactive P420 by hydrostatic pressure up to 2 kbar. CO flash photolysis experiments, as well as construction of a CYP119 homology model, suggest an open active site with greater solvent access than P450 (CYP101) and similar to that of P450 (CYP102). This communication represents the first molecular characterization of an extremophilic cytochrome P450.

Tachistoscopic and questionnaire methods for the measurement of psychological defences

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The transmission of bluetongue virus by embryo transfer in sheep

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Interferon production in lymphocyte cultures after rubella infection in humans

When stimulated with rubella virus irradiated with ultraviolet light, cultures of lymphocytes from individuals immune to rubella responded with production of 12-14 times more interferon than did cultures of lymphocytes from individuals susceptible to rubella. This property may be retained throughout life, since it was seen in individuals who had had rubella in their recent and remote pasts. Peak levels of interferon were detected six days after stimulation of lymphocytes with rubella virus antigen. In contrast, phytohemagglutinin induced production of interferon equally well in cultures of lymphocytes from persons immune and persons susceptible to rubella, with levels peaking three days after stimulation. Since there was a positive correlation among titers of hemagglutination-inhibiting antibody to rubella virus, incorporation of [14C]thymidine, and production of interferon after stimulation of lymphocyte cultures by rubella virus, interferon synthesis may be considered to be another measurable parameter of cell-mediated immunity in rubella.