Potential for ecological nonlinearities and thresholds to inform Pacific salmon management

AbstractEcology is often governed by nonlinear dynamics. Nonlinear ecological relationships can include thresholds—incremental changes in drivers that provoke disproportionately large ecological responses. Among the species that experience nonlinear and threshold dynamics are Pacific salmon (Oncorhynchus spp.). These culturally, ecologically, and economically significant fishes are in many places declining and management focal points. Often, managers can influence or react to ecological conditions that salmon experience, suggesting that nonlinearities, especially thresholds, may provide opportunities to inform decisions. However, nonlinear dynamics are not always invoked in management decisions involving salmon. Here, we review reported nonlinearities and thresholds in salmon ecology, describe potential applications that scientists and managers could develop to leverage nonlinear dynamics, and offer a path toward decisions that account for ecological nonlinearities and thresholds to improve salmon outcomes. It appears that nonlinear dynamics are not uncommon in salmon ecology and that many management arenas may potentially leverage them to enable more effective or efficient decisions. Indeed, decisions guided by nonlinearities and thresholds may be particularly desirable considering salmon management arenas are often characterized by limited resources and mounting ecological stressors, practical constraints, and conservation challenges. More broadly, many salmon systems are data‐rich and there are an extensive range of ecological contexts in which salmon are sensitive to anthropogenic decisions. Approaches developed to leverage nonlinearities in salmon ecology may serve as examples that may inform analogous approaches in other systems and taxa

Nelson, Pauline Munsch

Interview on 27 March 1997, Mesa, Arizona. Conducted by Betty & Chris Maier. Interview continued on 2 April 1997

The role of extended reality technology in healthcare education: Towards a learner-centred approach.

The use of extended reality (XR) technologies is growing rapidly in a range of industries from gaming to aviation. However, how this technology should be implemented in healthcare education is not well-documented in the literature. Learner-driven implementation of educational technology has previously been shown to be more effective than a technology-driven approach. In this paper we conduct a narrative literature review of relevant papers to explore the role of XR technologies in learner-driven approaches to healthcare educatio. This paper aims to evaluate the position of XR technologies in learner-centred pedagogical models, determine what functions of XR technologies can improve learner-centred approaches in healthcare education, and explore whether XR technologies can improve learning outcomes in healthcare education. We conclude that XR technologies have unique attributes that can improve learning outcomes when compared to traditional learning methods, but there is currently a shortfall in learner-centred implementation of XR technologies in healthcare education, where these technologies have the capacity to cause a paradigm shift

Improving mortality of coronary surgery over first four years of independent practice: retrospective examination of prospectively collected data from 15 surgeons

Objective To study the “learning curve” associated with independent practice in coronary artery surgery. Design Retrospective analysis of prospectively collected data. Setting All NHS centres in north west England that carry out cardiac surgery in adults. Participants 18 913 patients undergoing coronary artery surgery for the first time between April 1997 and March 2003, 5678 of whom were operated on by 15 surgeons in the first four years after their consultant appointment. Main outcome measures Observed and predicted mortality (EuroSCORE) for surgeons in their first, second, third, and fourth years after appointment as a consultant compared with figures for established surgeons. Results Overall mortality decreased over the six years of study (P = 0.01). Of the patients operated on by established surgeons or newly appointed consultants, 265/13 235 (2.0%) and 109/5678 (1.9%), respectively, died (P = 0.71). There was a progressive decrease in observed mortality with time after appointment as a consultant from 2.2% in the first year to 1.2% in the fourth year (P = 0.049). This result remained significant after adjustment for time and case mix (P = 0.019). Conclusions Mortality in patients operated on by newly appointed consultant surgeons is similar to mortality in patients operated on by established surgeons. There are significant decreases in crude and risk adjusted mortality in the four years after appointment. These findings should influence the nature of practice in newly appointed surgeons