The natural resting orientations of several species of nocturnal moth on tree trunks were recorded over a three-month period in eastern Ontario, Canada. Moths from certain genera exhibited resting orientation distributions that differed significantly from random, whereas others did not. In particular, Catocala spp. collectively tended to orient vertically, whereas subfamily Larentiinae representatives showed a variety of orientations that did not differ significantly from random. To understand why different moth species adopted different orientations, we presented human subjects with a computer-based detection task of finding and 'attacking' Catocala cerogama and Euphyia intermediata target images at different orientations when superimposed on images of sugar maple (Acer saccharum) trees. For both C. cerogama and E. intermediata, orientation had a significant effect on survivorship, although the effect was more pronounced in C. cerogama. When the tree background images were flipped horizontally the optimal orientation changed accordingly, indicating that the detection rates were dependent on the interaction between certain directional appearance features of the moth and its background. Collectively, our results suggest that the contrasting wing patterns of the moths are involved in background matching, and that the moths are able to improve their crypsis through appropriate behavioural orientation.

Whether hiding from predators, or avoiding battlefield casualties, camouflage is widely employed to prevent detection. Disruptive coloration is a seemingly well-known camouflage mechanism proposed to function by breaking up an object's salient features (for example their characteristic outline), rendering objects more difficult to recognize. However, while a wide range of animals are thought to evade detection using disruptive patterns, there is no direct experimental evidence that disruptive coloration impairs recognition. Using humans searching for computer-generated moth targets, we demonstrate that the number of edge-intersecting patches on a target reduces the likelihood of it being detected, even at the expense of reduced background matching. Crucially, eye-tracking data show that targets with more edge-intersecting patches were looked at for longer periods prior to attack, and passed-over more frequently during search tasks. We therefore show directly that edge patches enhance survivorship by impairing recognition, confirming that disruptive coloration is a distinct camouflage strategy, not simply an artefact of background matching.

Seawater Mg:Ca and Sr:Ca ratios are biogeochemical parameters reflecting the Earth–ocean–atmosphere dynamic exchange of elements. The ratios’ dependence on the environment and organisms' biology facilitates their application in marine sciences. Here, we present a measured single-laboratory dataset, combined with previous data, to test the assumption of limited seawater Mg:Ca and Sr:Ca variability across marine environments globally. High variability was found in open-ocean upwelling and polar regions, shelves/neritic and river-influenced areas, where seawater Mg:Ca and Sr:Ca ratios range from ∼4.40 to 6.40 mmol:mol and ∼6.95 to 9.80 mmol:mol, respectively. Open-ocean seawater Mg:Ca is semiconservative (∼4.90 to 5.30 mol:mol), while Sr:Ca is more variable and nonconservative (∼7.70 to 8.80 mmol:mol); both ratios are nonconservative in coastal seas. Further, the Ca, Mg, and Sr elemental fluxes are connected to large total alkalinity deviations from International Association for the Physical Sciences of the Oceans (IAPSO) standard values. Because there is significant modern seawater Mg:Ca and Sr:Ca ratios variability across marine environments we cannot absolutely assume that fossil archives using taxa-specific proxies reflect true global seawater chemistry but rather taxa- and process-specific ecosystem variations, reflecting regional conditions. This variability could reconcile secular seawater Mg:Ca and Sr:Ca ratio reconstructions using different taxa and techniques by assuming an error of 1 to 1.50 mol:mol, and 1 to 1.90 mmol:mol, respectively. The modern ratios’ variability is similar to the reconstructed rise over 20 Ma (Neogene Period), nurturing the question of seminonconservative behavior of Ca, Mg, and Sr over modern Earth geological history with an overlooked environmental effect.

Summary Inadequate supply of filtering facepiece respirators (FFRs) for healthcare workers during a pandemic such as the novel coronavirus outbreak (SARS-CoV-2) is a serious public health issue. The aim of this study was to synthesize existing data on the effectiveness of ultraviolet germicidal irradiation (UVGI) for N95 FFR decontamination. A systematic review (PROSPERO CRD42020176156) was conducted on UVGI in N95 FFRs using Embase, Medline, Global Health, Google Scholar, WHO feed, and MedRxiv. Two reviewers independently determined eligibility and extracted predefined variables. Original research reporting on function, decontamination, or mask fit following UVGI were included. Thirteen studies were identified, comprising 54 UVGI intervention arms and 58 N95 models. FFRs consistently maintained certification standards following UVGI. Aerosol penetration averaged 1.19% (0.70–2.48%) and 1.14% (0.57–2.63%) for control and UVGI arms, respectively. Airflow resistance for the control arms averaged 9.79 mm H 2 O (7.97–11.70 mm H 2 O) vs 9.85 mm H 2 O (8.33–11.44 mm H 2 O) for UVGI arms. UVGI protocols employing a cumulative dose >20,000 J/m 2 resulted in a 2-log reduction in viral load. A >3-log reduction was observed in seven UVGI arms using >40,000 J/m 2 . Impact of UVGI on fit was evaluated in two studies (16,200; 32,400 J/m 2 ) and no evidence of compromise was found. Our findings suggest that further work in this area (or translation to a clinical setting) should use a cumulative UV-C dose of 40,000 J/m 2 or greater, and confirm appropriate mask fit following decontamination.

IMPORTANCE Over the last 2 decades, bronchiolitis guidelines and improvement efforts focused on supportive care and reducing unnecessary tests, treatments, and hospitalization. There have been limited population-based studies examining hospitalization outcomes over time. OBJECTIVE To describe rates and trends in bronchiolitis hospitalization, intensive care unit (ICU) use, mortality, and costs. DESIGN, SETTING, AND PARTICIPANTS This cohort study used population-based health administrative data from April 1, 2004, to March 31, 2018, to identify bronchiolitis encounters using hospital discharge diagnosis codes in Ontario, Canada. Children younger than 2 years with and without bronchiolitis hospitalization were included. Data were analyzed from January 2020 to July 2021. MAIN OUTCOMES AND MEASURES Bronchiolitis hospitalization per 1000 person-years, ICU use per 1000 hospitalizations, mortality per 100 000 person-years, and costs per 1000 person-years adjusted to 2018 Canadian dollars and reported in 2018 US dollars.RESULTS Among 2 336 446 included children, 1 199 173 (51.3%) were male. During the study period, 43 993 children (1.9%) younger than 2 years had 48 058 bronchiolitis hospitalizations at 141 hospitals. Bronchiolitis accounted for 48 058 of 360 920 all-cause hospitalizations (13.3%) and 215 654 of 2 566 348 all-cause hospital days (8.4%) in children younger than 2 years. Bronchiolitis hospitalization was stable over time, at 14.0 (95% CI, 13.6-14.4) hospitalizations per 1000 person-years in 2004-2005 and 12.7 (95% CI, 12.2-13.1) hospitalizations per 1000 person-years in 2017-2018 (annual percent change [APC], 0%;