Critical Review of Visual Models for Police Use of Force Decision-Making.

Recent calls for widespread police reform include re-examination of existing training and practice surrounding the use of force (UOF, e.g., verbal and non-verbal communication, physical tactics, firearms). Visual models representing police UOF decision-making are used for both police training and public communication. However, most models have not been empirically developed or assessed in either the applied police or vision science literatures, representing significant gaps in knowledge. The purpose of the current review is to provide a novel, relevant, and practical analysis of the visual components of three common police UOF decision-making model types (circular, cyclical, staircase). We begin with a critical evaluation of the visual features specific to each model type (i.e., shape), followed by critical reviews of common visual features, including colour, implied motion, text, and clarity. The insights provided by the current work afford scientists from visual disciplines a unique opportunity to contribute meaningfully to the improvement of existing police UOF practices, with the goal of promoting public and occupational safety. To this end, we conclude with evidence-based recommendations for designing visual models that effectively promote training of police and communication of police UOF decision-making to the public.

Cold tolerance of the montane Sierra leaf beetle, Chrysomela aeneicollis.

Small ectothermic animals living at high altitude in temperate latitudes are vulnerable to lethal cold throughout the year. Here we investigated the cold tolerance of the leaf beetle Chrysomela aeneicollis living at high elevation in California's Sierra Nevada mountains. These insects spend over half their life cycle overwintering, and may therefore be vulnerable to winter cold, and prior studies have demonstrated that survival is reduced by exposure to summertime cold. We identify overwintering microhabitat of this insect, describe cold tolerance strategies in all life stages, and use microclimate data to determine the importance of snow cover and microhabitat buffering for overwinter survival. Cold tolerance varies among life history stages and is typically correlated with microhabitat temperature: cold hardiness is lowest in chill-susceptible larvae, and highest in freeze-tolerant adults. Hemolymph osmolality is higher in quiescent (overwintering) than summer adults, primarily, but not exclusively, due to elevated hemolymph glycerol. In nature, adult beetles overwinter primarily in leaf litter and suffer high mortality if early, unseasonable cold prevents them from entering this refuge. These data suggest that cold tolerance is tightly linked to life stage. Thus, population persistence of montane insects may become problematic as climate becomes more unpredictable and climate change uncouples the phenology of cold tolerance and development from the timing of extreme cold events.

Rotational behaviour of encapsulated pond snail embryos in diverse natural environments.

Encapsulated freshwater pond snail embryos display a cilia-driven rotation behaviour that is stimulated by artificially induced hypoxia. Previous studies have suggested that the mixing effect of this behaviour causes enhanced oxygen delivery to embryos within their egg capsules. Despite extensive laboratory-based studies describing this behaviour, it is unclear how this behaviour is used to cope with changes in oxygen concentration and other environmental factors in natural water bodies. We made field measurements of embryo rotation rates in laboratory-reared Helisoma trivolvis embryos placed in ponds of different trophic levels that ranged geographically from the southern Alberta prairie to the Rocky Mountains. Abiotic factors including temperature, pH, conductivity and water oxygen concentration were measured to understand how embryonic rotation is influenced by environmental conditions. Results showed that H. trivolvis embryos exhibit differences in rotational behaviour depending on the environmental conditions. Temperature and oxygen concentration were the primary factors significantly affecting rotation rates. The effect of oxygen concentration on rotation rates was not as widespread as observed under laboratory conditions, probably because the measured oxygen concentrations were above the range that influences embryonic rotation in the laboratory. The rotational behaviour of laboratory-reared Lymnaea stagnalis provided confirmation that embryos of other encapsulated pulmonates exhibit a similar rotational response in natural environments. These results suggest that embryo rotation is influenced by a complex interplay of environmental factors.