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In order to improve the understanding of how the high northern latitudes responded to the escalating warming which led to the middle Cretaceous super greenhouse climate, more temperature proxy records from the High Arctic are needed. One of the current obstacles in obtaining such records is poor age control on the Lower Cretaceous strata in the Boreal region. Here, we provide a biostratigraphic framework for the Rurikfjellet and Helvetiafjellet formations representing the lower part of the Lower Cretaceous succession on Spitsbergen. We also attempt to date the boundary between the Agardhfjellet and the Rurikfjellet formations. This study is based on dinoflagellate cysts (dinocysts) from three onshore cores (DH1, DH2 and DH5R) and three outcrop sections (Bohemanflya, Myklegardfjellet and Ullaberget). Relatively abundant and well-preserved dinocyst assemblages from the Rurikfjellet Formation date this unit as early Valanginian – early Barremian. The dinocyst assemblages from the Helvetiafjellet Formation are significantly impoverished and are characterized by reworking, but collectively indicate a Barremian–Aptian age for this formation.
Six experiments were conducted in 2018 on field sites located in Arkansas, Indiana, Michigan, Nebraska, Ontario, and Wisconsin to evaluate the off-target movement (OTM) of dicamba under field-scale conditions. The highest estimated dicamba injury in non-dicamba-resistant (DR) soybean was 50, 44, 39, 67, 15, and 44% injury for non-covered areas and 59, 5, 13, 42, 0, and 41% injury for covered areas during dicamba application in Arkansas, Indiana, Michigan, Nebraska, Ontario, and Wisconsin, respectively. The level of injury generally decreased exponentially as the downwind distance increased under covered and non-covered areas at all sites. There was an estimated 10% injury in non-DR soybean at 113, 8, 11, 8, and 8 m; and estimated 1% injury at 293, 28, 71, 15, and 19 m from the edge of treated field downwind when plants were not covered during dicamba application in Arkansas, Indiana, Michigan, Ontario and Wisconsin, respectively. Filter paper collectors placed from 4 up to 137 m downwind from the edge of the sprayed area suggested that the dicamba deposition reduced exponentially with distance. The greatest injury to non-DR soybean from dicamba OTM occurred at Nebraska and Arkansas (as far as 250 m). Non-DR soybean injury was greatest adjacent to the dicamba sprayed area but, injury decreased with no injury beyond 20 m downwind or any other direction from the dicamba sprayed area in Indiana, Michigan, Ontario, and Wisconsin. The presence of soybean injury under covered and non-covered areas during the spray period for primary drift suggests that secondary movement of dicamba was evident at five sites. Further research is needed to determine the exact forms of secondary movement of dicamba under different environmental conditions.
Women are more likely to be admitted to nursing home after stroke than men. Differences in patient characteristics and outcomes by sex after institutionalization are less understood. We examined sex differences in the characteristics and care needs of patients admitted to nursing home following stroke and their subsequent survival.
We identified patients with stroke newly admitted to nursing home between April 2011 and March 2016 in Ontario, Canada, with follow-up until March 2018 using linked administrative data. We calculated prevalence ratios and 95% confidence intervals (CIs) for the primary outcomes of dependence for activities of daily living, cognitive impairment, frailty, health instability, and symptoms of depression or pain, comparing women to men. The secondary outcome was all-cause mortality.
Among 4831 patients, 60.9% were women. Compared to men, women were older (median age [interquartile range, IQR]: 84 [78, 89] vs. 80 [71, 86]), more likely to be frail (prevalence ratio 1.14, 95% CI [1.08, 1.19]), have unstable health (1.45 [1.28, 1.66]), and experience symptoms of depression (1.25 [1.11, 1.40]) or pain (1.21 [1.13, 1.30]), and less likely to have aggressive behaviors (0.87 [0.80, 0.94]). Overall median survival was 2.9 years. In a propensity-score-matched cohort, women had lower mortality than men (hazard ratio 0.85, 95% CI [0.77, 0.94]), but in the age-stratified survival analysis, the survival advantage in women was limited to those aged 75 years and older.
Despite lower subsequent mortality, women admitted to nursing home after stroke required more care than men. Pain and depression are two treatable symptoms that disproportionately affect women.
Nutritional therapy is a cornerstone of burns management. The optimal macronutrient intake for wound healing after burn injury has not been identified, although high-energy, high-protein diets are favoured. This study aimed to identify the optimal macronutrient intake for burn wound healing. The Geometric Framework (GF) was used to analyse wound healing after a 10% TBSA contact burn in mice ad libitum fed one of 11 high-energy diets, varying in macronutrient composition with protein (P5%-60%), carbohydrate (C20%-75%) and fat (F20%-75%). In the GF study, the optimal ratio for wound healing was identified as a moderate-protein, high-carbohydrate diet with a protein:carbohydrate:fat (P:C:F) ratio of 1:4:2. High-carbohydrate intake was associated with lower mortality, improved body weight and a beneficial pattern of body fat reserves. Protein intake was essential to prevent weight loss and mortality, but a protein intake target of ~7 kJ/day (~15% of energy intake) was identified, above which no further benefit was gained. High-protein intake was associated with delayed wound healing and increased liver and spleen weight. As the GF study demonstrated that an initial very high-protein intake prevented mortality, a very high-protein, moderate-carbohydrate diet (P40:C42:F18) was specifically designed. The dynamic diet study was also designed to combine and validate the benefits of an initial very high-protein intake for mortality, and subsequent moderate-protein, high-carbohydrate intake for optimal wound healing. The dynamic feeding experiment showed switching from an initial very high-protein diet to the optimal moderate-protein, high-carbohydrate diet accelerated wound healing whilst preventing mortality and liver enlargement.
Many nanoparticles in fields such as heterogeneous catalysis undergo surface structural fluctuations during chemical reactions, which may control functionality. These dynamic structural changes may be ideally investigated with time-resolved in situ electron microscopy. We have explored approaches for extracting quantitative information from large time-resolved image data sets with a low signal to noise recorded with a direct electron detector on an aberration-corrected transmission electron microscope. We focus on quantitatively characterizing beam-induced dynamic structural rearrangements taking place on the surface of CeO2 (ceria). A 2D Gaussian fitting procedure is employed to determine the position and occupancy of each atomic column in the nanoparticle with a temporal resolution of 2.5 ms and a spatial precision of 0.25 Å. Local rapid lattice expansions/contractions and atomic migration were revealed to occur on the (100) surface, whereas (111) surfaces were relatively stable throughout the experiment. The application of this methodology to other materials will provide new insights into the behavior of nanoparticle surface reconstructions that were previously inaccessible using other methods, which will have important consequences for the understanding of dynamic structure–property relationships.
A central component of primates’ social ontogeny is play with conspecifics. Play is constrained by ecological factors, especially food abundance, and social play is most likely limited by partner availability, which in turn can be related to ecology. However, how much social and ecological factors collectively influence social play rates has not yet been investigated. We used a multivariate approach to test to what degree fruit and partner availability affected social play rates of wild immature chimpanzees in Taï National Park. As fruit abundance and partner availability increased, infant and juvenile play rates rose, with juvenile play being affected more by fruit abundance than infant play. Partner availability predicted infant play rates better during the low than the high fruit availability season, which was not the case for juvenile play. Our results indicate that young chimpanzees face a trade-off in allocating time or energy to foraging and social play, with foraging becoming increasingly dominant with age. This joint analysis of social and ecological factors suggests that food abundance modulates the effect of partner availability on social play rates in young chimpanzees.
Some of the greatest successes in infectious disease control rest on empirically grounded models of human and livestock infections. In contrast, disease control in wildlife has not always been as successful. Timely translation of knowledge into proposed management actions remains a challenge in several wildlife disease systems, one of which is pneumonia management in bighorn sheep throughout the North American West. Although pneumonia was recognised as a major impediment to bighorn sheep conservation >80 years ago, a series of challenges stymied the management decision-making process. Despite past obstacles, recent advances from long-term, intensive studies of marked individual sheep have motivated new interest in research-driven strategies for disease management in this system. The system provides an unusual opportunity to study an emerging pathogen disproportionately impacting immature animals through infections that originate from asymptomatically infected adult hosts. We tell the story of bighorn sheep pneumonia, emphasising the obstacles that historically hindered decision-making, the biological or logistical constraints underlying each decision point, and the particular empirical insights that clarified each constraint.
Conventional alloy design based on a single primary element has reached its limits in terms of performance optimization. An alloy design strategy with multi-principal elements has recently been uncovered to overcome this bottleneck. Multicomponent alloys, generally referred to as high-entropy alloys (HEAs), exhibit many promising properties, especially outstanding mechanical performance at cryogenic, ambient, and elevated temperatures. In this article, we focus on precipitation-hardened HEAs, which are potential candidates for next-generation structural materials, especially at high temperatures. The key issues involved include precipitation behaviors, phase stability, and phase control, all of which provide useful guidelines for further development of high-temperature materials with superior performance. In particular, we address the formation of cellular γ′ precipitates at grain boundaries, which is closely related to the embrittlement of HEAs at intermediate temperatures. Critical issues and design strategies in developing HEAs for high-temperature applications are also discussed.
Understanding changes in chemistry, microstructure, and physical properties during synthesis, processing, testing, and even service is vital for materials design and performance. Compared to traditional postmortem material characterization tools, in situ crystallographic characterization can provide considerable data and information on evolution of chemistry, dislocations, twinning, texture, and strains when a material is under external stimuli. Neutrons especially are able to probe material bulk properties and behaviors in extreme environments, thanks to their deep penetrating power and unique sensitivity to differentiate elements from lightweight to transition-metal atoms. In this article, we introduce and describe a diffractometer named VULCAN, which is located at Oak Ridge National Laboratory. This represents a powerful tool to understand materials properties and behaviors under complex environments, in particular, at high temperatures.