Experimental observations indicate that positive feedback plays an important role for maintaining human balance in the upright position. This observation is used to motivate an investigation of a simple switch-like controller for postural sway in which corrective movements are made only when the vertical displacement angle exceeds a certain threshold. This mechanism is shown to be consistent with the experimentally observed variations in the two-point correlation for human postural sway. Analysis of first-passage times for this model suggests that this control strategy may slow escape by taking advantage of two intrinsic properties of a stochastic unstable first-order delay differential equation: (i) time delay and (ii) the possibility that the dynamics can be 'temporarily confined' near the origin.

Background: Nurses played a critical role in providing care for patients throughout the COVID-19 pandemic. Aim: This study aimed to explore perspectives of Australian palliative care nurses regarding the impact of COVID-19 on the provision of care for patients with advanced illness, or at the end of life. Methods: The authors conducted a survey of palliative care nurses in ward- and consultation-based roles at a metropolitan health service in Victoria, Australia. Findings: A total of 24 out of 39 nurses completed the survey. Responses included strong themes of fear of COVID-19 and sadness about separating dying patients from their families. Conclusion: Delivery of palliative care changed at an individual and service level. Importantly, there were strong themes of adapting to change and ‘soldiering on’ with the core business of palliative care.