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Examine how changes in sleep duration, objectively measured by activity trackers, impact weight gain in incoming college freshman.Supplemental data for this article can be accessed online at https://doi.org/10.1080/07448481.2022.2032720.

The mechanism responsible for the damping of the large-scale, azimuthally directed jets observed at Jupiter's surface is not well known, but electromagnetic forces are suspected to play a role as the planet's electrical conductivity increases radially with depth. To isolate the jet damping process, we carry out a suite of direct numerical simulations of quasi-two-dimensional, horizontally periodic Rayleigh-Bénard convection with stress-free boundary conditions in the presence of an external, vertical magnetic field. Jets, punctuated by intermittent convective bursts, develop at Rayleigh numbers (Ra, ratio of buoyancy to diffusion) beyond 10^{5} when the magnetic field is relatively weak. Five primary flow regimes are found by varying 10^{3}≤Ra≤10^{10} and the Chandrasekhar number (Ch, ratio of Lorentz to viscosity) 0≤Ch≤10^{6}: (i) steady convection rolls, (ii) steady magneto-columns, (iii) unsteady to turbulent magneto-plumes, (iv) horizontally drifting magneto-plumes, and (v) jets with intermittent turbulent convective bursts. We parse the parameter space using transitions derived from the interaction parameter (N, ratio of Lorentz to inertia). The transition to the regime dominated by jets has the most immediate applications to the magnetic damping of Jovian jet flows, where the separation between jets and a magnetically constrained system occurs at a jet-based interaction parameter value of N_{J}≈1. We approximate the value of the Jovian interaction parameter as a function of depth, and find that the jets may brake at ≈6000km below the surface, which is deeper than recent estimates from NASA's Juno mission. This suggests that mechanisms in addition to electromagnetic forces are likely required to fully truncate the jets.

The interplay between convective, rotational and magnetic forces defines the dynamics within the electrically conducting regions of planets and stars. Yet their triadic effects are separated from one another in most studies, arguably due to the richness of each subset. In a single laboratory experiment, we apply a fixed heat flux, two different magnetic field strengths and one rotation rate, allowing us to chart a continuous path through Rayleigh–Bénard convection (RBC), two regimes of magnetoconvection, rotating convection and two regimes of rotating magnetoconvection, before finishing back at RBC. Dynamically rapid transitions are determined to exist between jump rope vortex states, thermoelectrically driven magnetoprecessional modes, mixed wall- and oscillatory-mode rotating convection and a novel magnetostrophic wall mode. Thus, our laboratory ‘pub crawl’ provides a coherent intercomparison of the broadly varying responses arising as a function of the magnetorotational forces imposed on a liquid-metal convection system.

The electric grid plays a crucial role in the functioning of American households, schools, businesses, and health facilities, as well as national security. Action is needed to address the vulnerability of the grid to natural disasters, which are increasing in frequency and intensity due to climate change. States that are particularly under threat include those in the Southeast, such as Louisiana, Mississippi, and Florida, where hurricanes and severe storms can be especially destructive. States in this region also typically rely on natural gas as a primary source of energy, which upholds a centralized grid structure that is more susceptible to widespread power outages than a distributed structure. Power outages, which disproportionately impact low-income communities, can be detrimental to health and safety during a natural disaster by severing access to communication and necessary medical equipment. Using Louisiana as a case study, we recommend one policy through which the state can transition to a more distributed structure; the Louisiana Public Service Commission should revise the 2019 legislation that financially disincentivizes customers to install solar panels, and instead expand the benefits for these customers. This change will increase the proliferation of solar energy, which can serve as power sources in a distributed grid. Solar panels, coupled with battery storage, can reduce the likelihood of power outages during extreme weather events. Expanding the use of renewable energy in Louisiana could encourage other states in the region to also make this shift, serving as a model for stronger climate adaptation across the country.

To assess the efficacy of ramelteon in preventing delirium, an acute neuropsychiatric condition associated with increased morbidity and mortality, in the perioperative, ICU setting.Parallel-arm, randomized, double-blinded, placebo-controlled trial.Academic medical center in La Jolla, California.Patients greater than or equal to 18 years undergoing elective pulmonary thromboendarterectomy.Ramelteon 8 mg or matching placebo starting the night prior to surgery and for a maximum of six nights while in the ICU.Incident delirium was measured twice daily using the Confusion Assessment Method-ICU. The safety outcome was coma-free days assessed by the Richmond Agitation-Sedation Scale. One-hundred twenty participants were enrolled and analysis completed in 117. Delirium occurred in 22 of 58 patients allocated to placebo versus 19 of 59 allocated to ramelteon (relative risk, 0.8; 95% CI, 0.5-1.4; p = 0.516). Delirium duration, as assessed by the number of delirium-free days was also similar in both groups (placebo median 2 d [interquartile range, 2-3 d] vs ramelteon 3 d [2-5 d]; p = 0.181). Coma-free days was also similar between groups (placebo median 2 d [interquartile range, 1-3 d] vs ramelteon 3 d [2-4 d]; p = 0.210). We found no difference in ICU length of stay (median 4 d [interquartile range, 3-5 d] vs 4 d [3-6 d]; p = 0.349), or in-hospital mortality (four vs three deaths; relative risk ratio, 0.7; 95% CI, 0.2-3.2; p = 0.717), all placebo versus ramelteon, respectively.Ramelteon 8 mg did not prevent postoperative delirium in patients admitted for elective cardiac surgery.

We compare the results of using a Random Forest Classifier with the results of using Nonparametric Discriminant Analysis to classify whether a filament channel (in the case of a filament eruption) or an active region (in the case of a flare) is about to produce an event. A large number of descriptors are considered in each case, but it is found that only a small number are needed in order to get most of the improvement in performance over always predicting the majority class. There is little difference in performance between the two classifiers, and neither results in substantial improvements over simply predicting the majority class.