21 research outputs found

    Neptune Odyssey: A Flagship Concept for the Exploration of the Neptune–Triton System

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    The Neptune Odyssey mission concept is a Flagship-class orbiter and atmospheric probe to the Neptune-Triton system. This bold mission of exploration would orbit an ice-giant planet to study the planet, its rings, small satellites, space environment, and the planet-sized moon Triton. Triton is a captured dwarf planet from the Kuiper Belt, twin of Pluto, and likely ocean world. Odyssey addresses Neptune system-level science, with equal priorities placed on Neptune, its rings, moons, space environment, and Triton. Between Uranus and Neptune, the latter is unique in providing simultaneous access to both an ice giant and a Kuiper Belt dwarf planet. The spacecraft - in a class equivalent to the NASA/ESA/ASI Cassini spacecraft - would launch by 2031 on a Space Launch System or equivalent launch vehicle and utilize a Jupiter gravity assist for a 12 yr cruise to Neptune and a 4 yr prime orbital mission; alternatively a launch after 2031 would have a 16 yr direct-to-Neptune cruise phase. Our solution provides annual launch opportunities and allows for an easy upgrade to the shorter (12 yr) cruise. Odyssey would orbit Neptune retrograde (prograde with respect to Triton), using the moon's gravity to shape the orbital tour and allow coverage of Triton, Neptune, and the space environment. The atmospheric entry probe would descend in ~37 minutes to the 10 bar pressure level in Neptune's atmosphere just before Odyssey's orbit-insertion engine burn. Odyssey's mission would end by conducting a Cassini-like "Grand Finale,"passing inside the rings and ultimately taking a final great plunge into Neptune's atmosphere

    100 kasus kedokteran klinis

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    xiii, 262 hlm. ; ilus. ; tab. ; 25 cm

    Does the Effectiveness of a Medicine Copay Voucher Vary by Baseline Medication Out‐Of‐Pocket Expenses? Insights From ARTEMIS

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    Background Persistence to P2Y12 inhibitors after myocardial infarction (MI) remains low. Out‐of‐pocket cost is cited as a factor affecting medication compliance. We examined whether a copayment intervention affected 1‐year persistence to P2Y12 inhibitors and clinical outcomes. Methods and Results In an analysis of ARTEMIS (Affordability and Real‐World Antiplatelet Treatment Effectiveness After Myocardial Infarction Study), patients with MI discharged on a P2Y12 inhibitor were stratified by baseline out‐of‐pocket medication burden: low (00–49 per month), intermediate (5050–149 per month), and high (≥$150 per month). The impact of the voucher intervention on 1‐year P2Y12 inhibitor persistence was examined using a logistic regression model with generalized estimating equations. We assessed the rates of major adverse cardiovascular events among the groups using a Kaplan–Meier estimator. Among 7351 MI‐treated patients at 282 hospitals, 54.2% patients were in the low copay group, 32.0% in the middle copay group, and 13.8% in the high copay group. Patients in higher copay groups were more likely to have a history of prior MI, heart failure, and diabetes compared with the low copay group (all P<0.0001). Voucher use was associated with a significantly higher likelihood of 1‐year P2Y12 inhibitor persistence regardless of copayment tier (low copay with versus without voucher: adjusted odds ratio [OR], 1.44 [95% CI, 1.25–1.66]; middle copay: adjusted OR, 1.63 [95% CI, 1.37–1.95]; high copay group: adjusted OR, 1.41 [95% CI, 1.05–1.87]; P interaction=0.42). Patients in the high copay group without a voucher had similar risk of 1‐year major adverse cardiovascular events compared with patients in the high copay group with a voucher (adjusted hazard ratio, 0.89 [95% CI, 0.66–1.21]). Conclusions Medication copayment vouchers were associated with higher medication persistence at 1 year following an MI, regardless of out‐of‐pocket medication burden. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02406677

    Energetic Particles and Acceleration Regions Over Jupiter's Polar Cap and Main Aurora: A Broad Overview

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    Previous Juno mission event studies revealed powerful electron and ion acceleration, to 100s of kiloelectron volts and higher, at low altitudes over Jupiter's main aurora and polar cap (PC; poleward of the main aurora). Here we examine 30–1200 keV JEDI-instrument particle data from the first 16 Juno orbits to determine how common, persistent, repeatable, and ordered these processes are. For the PC regions, we find (1) upward electron angle beams, sometimes extending to megaelectron volt energies, are persistently present in essentially all portions of the polar cap but are generated by two distinct and spatially separable processes. (2) Particle evidence for megavolt downward electrostatic potentials are observable for 80 of the polar cap crossings and over substantial fractions of the PC area. For the main aurora, with the orbit favoring the duskside, we find that (1) three distinct zones are observed that are generally arranged from lower to higher latitudes but sometimes mixed. They are designated here as the diffuse aurora (DifA), Zone-I (ZI(D)) showing primarily downward electron acceleration, and Zone-II (ZII(B)) showing bidirectional acceleration with the upward intensities often greater than downward intensities. (2) ZI(D) and ZII(B) sometimes (but not always) contain, respectively, downward electron inverted Vs and downward proton inverted Vs, (potentials up to 400 kV) but, otherwise, have broadband distributions. (3) Surprisingly, both ZI(D) and ZII(B) can generate equally powerful auroral emissions. It is suggested but demonstrated for intense portions of only one auroral crossing, that ZI(D) and ZII(B) are associated, respectively, with upward and downward electric currents

    Implications of Juno energetic particle observations over Jupiter’s polar regions for understanding magnetosphere-ionosphere coupling at strongly magnetized planets

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    Juno obtained low altitude space environment measurements over Jupiter’s poles on 27 August 2016 and then again on 11 December 2016. Particle distributions were observed over the poles within the downward loss cones sufficient to power nominally observed auroral emissions and with the characteristic energies anticipated from remote spectroscopic ultra-violet auroral imaging. However, the character of the particle distributions apparently causing the most intense auroral emissions were very different from those that cause the most intense aurora at Earth and from those anticipated from prevailing models of magnetosphere-ionosphere coupling at Jupiter. The observations are highly suggestive of a predominance of a magnetic field-aligned stochastic acceleration of energetic auroral electrons rather than the more coherent acceleration processes anticipated. The Juno observations have similarities to observations observed at higher altitudes at Saturn by the Cassini mission suggesting that there may be some commonality between the magnetosphere-ionosphere couplings at these two giant planets. Here we present the Juno energetic particle observations, discuss their similarities and differences with published observations from Earth and Saturn, and deliberate on the implications of these finding for general understanding of magnetosphere-ionosphere coupling processes

    Can we integrate ecological approaches to improve plant selection for green infrastructure?

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    Modern cities are dominated by impervious surfaces that absorb, store and release heat in summer, create large volumes of runoff and provide limited biodiversity habitat and poor air quality can also be a health issue. Future climate change, including more frequent and extreme weather events will likely exacerbate these issues. Green infrastructure such as parks, gardens, street trees and engineered technologies such as green roofs and walls, facades and raingardens can help mitigate these problems. This relies on selecting plants that can persist in urban environments and improve stormwater retention, cooling, biodiversity and air pollution. However, plant selection for green infrastructure is challenging where there is limited information on species tolerance to heat and water variability or how these species can deliver multiple benefits. Therefore, we draw on research to illustrate how plant performance for green infrastructure can be inferred from plant attributes (i.e., traits) or from analysis of their natural distribution. We present a new framework for plant selection for green infrastructure and use a case study to demonstrate how this approach has been used to select trees and shrubs for Australian cities. We have shown through the case study and examples, how plant traits and species’ natural distribution can be used to overcome the lack of information on tolerance to both individual and multiple stressors; and how species contribute to the provision of benefits such as stormwater retention, cooling, biodiversity and air pollution mitigation. We also discuss how planting design and species diversity can contribute to achieving multiple benefits to make the most of contested space in dense cities, and to also reduce the risk of failure in urban greening
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