NASA's OSIRIS-REx spacecraft collected samples from carbonaceous near-Earth asteroid (101955) Bennu on October 20, 2020, and will deliver them to the Earth on September 24, 2023. The samples will be ...processed at the NASA Johnson Space Center (JSC), where most of the sample collection will be subsequently curated in a new cleanroom suite. The spacecraft collected loose regolith two ways: in a bulk sample chamber capable of holding up to 2 kg, and on industrial Velcro “contact pads” intended to collect small particles at the surface. Included in the JSC collection will be the bulk sample, the contact pads, contamination-monitoring witness plates, and supporting hardware. Planning for the curation of the samples and hardware started at the earliest phase of proposal development and continued in parallel with project development and execution. Because a major mission goal is characterization of organic compounds in the Bennu samples, extra effort was spent in the design stage to ensure a clean curation environment. Here, we describe the preparations to receive the sample, including the design, construction, outfitting, and monitoring of the cleanrooms at JSC; the planned recovery of the sample-containing capsule when it lands on Earth; and the approach to characterizing and cataloging the samples. These curation efforts will result in the distribution of pristine Bennu samples from JSC to the OSIRIS-REx science team, international partners, and the global scientific community for years to come.
We use an infrared data set captured between 1984 and 2017 using several instruments and observatories to report five rare equatorial disturbances that completely altered the appearance of Jupiter's ...equatorial zone (EZ): the clearance of tropospheric clouds revealed a new 5‐μm‐bright band encircling the planet at the equator, accompanied by large 5‐μm‐bright filaments. Three events were observed in ground‐based images in 1973, 1979, and 1992. We report and characterize for the first time the entire evolution of two new episodes of this unusual EZ state that presented their maximum 5‐μm‐brightness in December 1999 and February 2007, coinciding with a brown coloration south of the equator and with large bluish filaments and white plumes in the northern EZ at visible wavelengths. We characterize their typical infrared‐bright lifetimes of 12–18 months, with possible periodicities of 6–8 or 13–14 years. We predict that a full‐scale equatorial disturbance could occur in 2019–2021.
Plain Language Summary
Jupiter's banded structure, white zones (cloud‐covered regions) and brown belts (cloud‐free regions), exhibits dramatic planetary‐scale changes. In this paper, we report five rare events at Jupiter's equatorial zone that changed the appearance of this zone completely at the cloud forming region (1–4 bar), leaving a bright band at the equator, accompanied by narrow and bright filaments (festoons) at the northern equatorial zone. We use ground‐based 5‐μm data, which reveal the thermal emission from 1 to 4 bar region (bellow the ammonia cloud), captured between June 1984 and August 2017 (almost three Jovian years) to report and characterize for the first time two new disturbances at Jupiter's equatorial zone that took place in 1999–2000 and 2006–2007. We found that changes in the cloud morphology at the equatorial zone during these disturbances occurred first at the cloud tops (~700 mbar), months before they were observed at the cloud forming region at 1–4 bar. We also found that these disturbances are confined at the cloud deck (~150 mbar to 4 bar), lasting 12–18 months. After analyzing five documented equatorial zone disturbances, we conclude that these events are periodic/stochastic with typical intervals of 6–8 or 13–14 years. We predict a new disturbance in 2019–2021, during Juno's exploration epoch.
Key Points
We report a pattern of cloud clearance events that completely change the appearance of Jupiter's equatorial zone in the infrared
The equatorial disturbance forms in less than 1 month and dissipates over 4 months, with a typical lifetime of 12–18 months at 5 μm
A 6‐ to 8‐ or 13‐ to 14‐year periodicity is found. We predict a new equatorial zone disturbance at 5 μm to occur in 2019–2021
Abstract
Background:Many coronary heart disease (CHD) events occur in individuals classified as intermediate risk by commonly used assessment tools. Over half the individuals presenting with a severe ...cardiac event, such as myocardial infarction (MI), have at most one risk factor as included in the widely used Framingham risk assessment. Individuals classified as intermediate risk, who are actually at high risk, may not receive guideline recommended treatments. A clinically useful method for accurately predicting 5-year CHD risk among intermediate risk patients remains an unmet medical need.
Objective:This study sought to develop a CHD Risk Assessment (CHDRA) model that improves 5-year risk stratification among intermediate risk individuals.
Methods:Assay panels for biomarkers associated with atherosclerosis biology (inflammation, angiogenesis, apoptosis, chemotaxis, etc.) were optimized for measuring baseline serum samples from 1084 initially CHD-free Marshfield Clinic Personalized Medicine Research Project (PMRP) individuals. A multivariable Cox regression model was fit using the most powerful risk predictors within the clinical and protein variables identified by repeated cross-validation. The resulting CHDRA algorithm was validated in a Multiple-Ethnic Study of Atherosclerosis (MESA) case-cohort sample.
Results:A CHDRA algorithm of age, sex, diabetes, and family history of MI, combined with serum levels of seven biomarkers (CTACK, Eotaxin, Fas Ligand, HGF, IL-16, MCP-3, and sFas) yielded a clinical net reclassification index of 42.7% (p < 0.001) for MESA patients with a recalibrated Framingham 5-year intermediate risk level. Across all patients, the model predicted acute coronary events (hazard ratio = 2.17, p < 0.001), and remained an independent predictor after Framingham risk factor adjustments.
Limitations:These include the slightly different event definition with the MESA samples and inability to include PMRP fatal CHD events.
Conclusions:A novel risk score of serum protein levels plus clinical risk factors, developed and validated in independent cohorts, demonstrated clinical utility for assessing the true risk of CHD events in intermediate risk patients. Improved accuracy in cardiovascular risk classification could lead to improved preventive care and fewer deaths.
Accurate estimates of leaf area index (LAI) could provide useful information to forest managers, but due to difficulties in measurement, leaf area is rarely used in decision-making. A reliable ...approach to remotely estimating LAI would greatly facilitate its use in forest management. This study investigated the potential for using small-footprint LiDAR, a laser-based remote sensing tool capable of characterizing the vertical structure of forest vegetation, to generate estimates of individual tree leaf area based on LiDAR-derived estimates of tree height and crown dimensions. At a 16-year-old loblolly pine spacing trial in Mississippi, LiDAR-derived estimates of leaf area based on height and crown diameter were on average within 0.1
m
2 of ground-based estimates for trees on plots initially planted at a 1.5
m
×
1.5
m spacing. For trees on plots originally planted at square spacings of 2.4
m and 3.0
m, LiDAR-based leaf area estimates were below ground-based estimates by 5.8
m
2 and 14.5
m
2, respectively. At a study site in Texas, LiDAR-derived estimates of leaf area for 4-year-old loblolly pine were, on average, within 0.4
m
2 of ground-based estimates. Errors in leaf area estimates were largely due to the inability to generate accurate LiDAR-based estimates of crown dimensions. Tree heights were accurately estimated with LiDAR at both locations, but crown diameter and vertical crown dimensions at the Mississippi site were underestimated on average by 21% and 3%, respectively.
The effect of activation and reaction treatments on the resulting phase transformations in a commercial, precipitated, and spray-dried Fe2O3-CuO-K2O Fischer-Tropsch catalyst has been studied. The ...catalyst was activated in flowing H2, CO, and a H2/CO = 0.7/1.0 mixture. The pretreatment method caused these catalysts to exhibit significant differences in their catalytic activity for CO hydrogenation. The microstructure of these catalysts was studied by electron microscopy and other bulk and surface characterization techniques to understand the phenomena responsible for these differences. We observe that magnetite transforms into carbide as the catalyst is activated, causing the crystals of magnetite to break down into smaller crystallites of the carbide phase. Deposition of carbon on the carbide surface causes the carbide crystallites to further separate from each other. Our results suggest that magnetite has negligible catalytic activity for FT synthesis whereas carbide formation is necessary before the catalyst becomes active. The extent of transformation into carbide correlates well with catalyst activity during the activation step.
Summary
Multiple direct‐acting antiviral (DAA)‐based regimens are now available for all hepatitis C virus (HCV) genotypes (GTs). Because HCV GT 4, 5 and 6 are less common in the United States (US) ...and worldwide, relatively small numbers of participants with these GTs were evaluated in individual clinical trials. To provide a comprehensive description of subtype diversity and treatment outcomes in clinical trials for these less common GTs, we analysed data from 744 participants with HCV GT4 (n = 573), GT5 (n = 81), or GT6 (n = 90) across 18 clinical trials of DAA regimens. These data are from US New Drug Applications submitted between 2014 and 2017, and our analyses included only approved regimens. Excluding unresolved or mixed subtypes, the distribution of reported GT4 subtypes was 49% 4a, 31% 4d and 16% for one of 14 other subtypes. The distribution of GT6 subtypes was 39% 6a, 27% 6e, 8% 6 L and 23% for one of 11 other subtypes. Across approved regimens, sustained virologic response rates 12 weeks post‐treatment (SVR12) for GT 4, 5 and 6 ranged from 91% to 100%, 93% to 97% and 96% to 100%, respectively. SVR12 by GT4 subtype ranged from 96% to 100% for 4a and 81% to 100% for 4d. Virologic failures occurred in GT 4a, 4b, 4d and 4r. For GT6, SVR12 was 100% for all subtypes except 6 L, for which 1 of 7 participants experienced virologic failure. To our knowledge, this is the largest compilation of HCV GT 4, 5 or 6 clinical trial data. These analyses may be useful for clinicians treating HCV GT 4, 5 or 6.
Assessing the trophic ecology of fur seals is essential for defining their roles as a top predator in Antarctic marine ecosystems. To this end, we examined the diet of Antarctic fur seals,
...Arctocephalus gazella
, in the South Shetlands. While previous studies have considered the diet of this species at this location in summer, to the best of our knowledge, this is the first study to report on the diet of this population in winter, thus adding essential information on the extent of seasonal variation. A total of 224 scats were collected in the winter 2004 (
n
= 118) and summer 2004/2005 (
n
= 106) on the coasts of Stranger Point, Isla 25 de Mayo/King George. For the total study period krill (
Euphausia superba
) was the main prey taxon, followed by fish, cephalopods and penguins. During winter
Pleuragramma antarcticum
was dominant, while myctophids were almost absent. Conversely, in summer
Electrona antarctica
and
Gymnoscopelus nicholsi
, followed by
P. antarcticum
, dominated the fish diet. It is concluded that fur seals centred their foraging activity on a krill community and fish associated with krill aggregations.
With an equilibrium temperature of 1200 K, TrES-1 is one of the coolest hot Jupiters observed by Spitzer. It was also the first planet discovered by any transit survey and one of the first exoplanets ...from which thermal emission was directly observed. We analyzed all Spitzer eclipse and transit data for TrES-1 and obtained its eclipse depths and brightness temperatures in the 3.6 mu m (0.083% + or - 0.024%, 1270 + or - 110 K), 4.5 mu m (0.094% + or - 0.024%, 1126 + or - 90 K), 5.8 mu m (0.162% + or - 0.042%, 1205 + or - 130 K), 8.0 mu m (0.213% + or - 0.042%, 1190 + or - 130 K), and 16 mu m (0.33% + or - 0.12%, 1270 + or - 310 K) bands. The eclipse depths can be explained, within 1sigma errors, by a standard atmospheric model with solar abundance composition in chemical equilibrium, with or without a thermal inversion. The combined analysis of the transit, eclipse, and radial-velocity ephemerides gives an eccentricity of e = 0.033 super(+0.015) sub(-0.031) , consistent with a circular orbit. Since TrES-1's eclipses have low signal-to-noise ratios, we implemented optimal photometry and differential-evolutionMarkov ChainMonte Carlo (MCMC) algorithms in our Photometry for Orbits, Eclipses, and Transits pipeline. Benefits include higher photometric precision and~10 times faster MCMC convergence, with better exploration of the phase space and no manual parameter tuning.
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