Spacecraft sample collection and subsurface excavation of asteroid (101955) Bennu.

Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging and spectral data collected during and after retrieval of a sample from Bennu's surface. The sampling event mobilized rocks and dust into a debris plume, excavating a 9-meter-long elliptical crater. This exposed material is darker, spectrally redder, and more abundant in fine particulates than the original surface. The bulk density of the displaced subsurface material was 500 to 700 kilograms per cubic meter, which is about half that of the whole asteroid. Particulates that landed on instrument optics spectrally resemble aqueously altered carbonaceous meteorites. The spacecraft stored 250 ± 101 grams of material, which will be delivered to Earth in 2023.

The Patient Pathway for Men with Chronic Urinary Retention: Treatments, Complications, and Consequences.

OBJECTIVE: To explore the treatment options for chronic urinary retention (CUR) in men, including treatment-related complications and consequences. METHODS: This retrospective cohort study included male patients diagnosed with a non-neurogenic, symptomatic and/or high-risk, CUR >150 mL in a large Dutch non-academic teaching hospital. Data for treatments, complications, and consequences (eg, diagnostics, additional treatments, and hospital contact) were recorded and incidence rate ratios (IRRs) were calculated. RESULTS: We enrolled 177 patients (median age, 77 years; range, 44-94) with a median follow-up of 68 months (range, 1-319) during which they had a median of 8 events (range, 1-51). Most patients initially received a urethral catheter (74%) and some form of catheterization as their final treatment (87%). Compared with non-surgical cases, catheterization was more likely to be stopped after de-obstructive prostate surgery (IRR, 4.18; P < 0.001). Urinary tract infection (IRR, 3.68; P < 0.001) and macroscopic hematuria (IRR, 5.35; P < 0.001) were more common with catheterization, but post-renal problems were more likely in patients with no catheterization (IRR, 25.36; P < 0.001). The lowest chance of complication was with clean intermittent catheterization, and complications were usually managed in outpatient (77%) or emergency (6%) departments, rather than by admission (17%). CONCLUSION: Most patients require catheterization for CUR, with clean intermittent catheterization preferred due to its comparatively lower complication risk. De-obstructive prostate surgery increases the chance of stopping catheterization and may be considered in suitable cases.

Episodes of particle ejection from the surface of the active asteroid (101955) Bennu.

Active asteroids are those that show evidence of ongoing mass loss. We report repeated instances of particle ejection from the surface of (101955) Bennu, demonstrating that it is an active asteroid. The ejection events were imaged by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer) spacecraft. For the three largest observed events, we estimated the ejected particle velocities and sizes, event times, source regions, and energies. We also determined the trajectories and photometric properties of several gravitationally bound particles that orbited temporarily in the Bennu environment. We consider multiple hypotheses for the mechanisms that lead to particle ejection for the largest events, including rotational disruption, electrostatic lofting, ice sublimation, phyllosilicate dehydration, meteoroid impacts, thermal stress fracturing, and secondary impacts.