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Users struggle to select strong passwords. System-assigned passwords address this problem, but they can be difficult for users to memorize. While password managers can help store system-assigned passwords, there will always be passwords that a user needs to memorize, such as their password manager’s master password. As such, there is a critical need for research into helping users memorize system-assigned passwords. In this work, we compare three different designs for password memorization aids inspired by the method of loci or memory palace. Design One displays a two-dimensional scene with objects placed inside it in arbitrary (and randomized) positions, with Design Two fixing the objects’ position within the scene, and Design Three displays the scene using a navigable, three-dimensional representation. In an A-B study of these designs, we find that, surprisingly, there is no statistically significant difference between the memorability of these three designs, nor that of assigning users a passphrase to memorize, which we used as the control in this study. However, we find that when perfect recall failed, our designs helped users remember a greater portion of the encoded system-assigned password than did a passphrase, a property we refer to as durability. Our results indicate that there could be room for memorization aids that incorporate fuzzy or error-correcting authentication. Similarly, our results suggest that simple (i.e., cheap to develop) designs of this nature may be just as effective as more complicated, high-fidelity (i.e., expensive to develop) designs. 

Agriculture’s global environmental impacts are widely expected to continue expanding, driven by population and economic growth and dietary changes. This Review highlights climate change as an additional amplifier of agriculture’s environmental impacts, by reducing agricultural productivity, reducing the efficacy of agrochemicals, increasing soil erosion, accelerating the growth and expanding the range of crop diseases and pests, and increasing land clearing. We identify multiple pathways through which climate change intensifies agricultural greenhouse gas emissions, creating a potentially powerful climate change–reinforcing feedback loop. The challenges raised by climate change underscore the urgent need to transition to sustainable, climate-resilient agricultural systems. This requires investments that both accelerate adoption of proven solutions that provide multiple benefits, and that discover and scale new beneficial processes and food products. 

Quasi-periodic plasmoid formation at the tip of magnetic streamer structures is observed to occur in experiments on the Big Red Ball as well as in simulations of these experiments performed with the extended magnetohydrodynamics code, NIMROD. This plasmoid formation is found to occur on a characteristic time scale dependent on pressure gradients and magnetic curvature in both experiment and simulation. Single mode, or laminar, plasmoids exist when the pressure gradient is modest, but give way to turbulent plasmoid ejection when the system drive is higher, which produces plasmoids of many sizes. However, a critical pressure gradient is also observed, below which plasmoids are never formed. A simple heuristic model of this plasmoid formation process is presented and suggested to be a consequence of a dynamic loss of equilibrium in the high- $$\beta$$ region of the helmet streamer. This model is capable of explaining the periodicity of plasmoids observed in the experiment and simulations, and produces plasmoid periods of 90 minutes when applied to two-dimensional models of solar streamers with a height of $$3R_\odot$$ . This is consistent with the location and frequency at which periodic plasma blobs have been observed to form by Large Angle and Spectrometric Coronograph and Sun Earth Connection Coronal and Heliospheric Investigation instruments. 

Abstract Anthropogenic changes have altered the historical distributions of many North American taxa. As environments shift, ecological and evolutionary processes can combine in complex ways to either stimulate or inhibit range expansion. Here, we examined the role of evolution in a rapid range expansion whose ecological context has been well‐documented, Anna's Hummingbird (Calypte anna). Previous studies have suggested that theC. annarange expansion is the result of an ecological release facilitated by human‐mediated environmental changes, where access to new food sources have allowed further filling of the abiotic niche. We examined the role of gene flow and adaptation during range expansion from their native California breeding range, north into Canada and east into New Mexico and Texas, USA. Using low coverage whole genome sequencing we found high genetic diversity, low divergence, and little evidence of selection on the northern and eastern expansion fronts. Additionally, there are no clear barriers to gene flow across the native and expanded range. The lack of selective signals between core and expanded ranges could reflect (i) an absence of novel selection pressure in the expanded range (supporting the ecological release hypothesis), (ii) swamping of adaptive variation due to high gene flow, or (iii) limitations of genome scans for detecting small shifts in allele frequencies across many loci. Nevertheless, our results provide an example where strong selection is not apparent during a rapid, contemporary range shift.