•Compare predictions of floor-fractured crater Bouguer anomaly with observations.•Band-filtered Bouguer anomalies show spatial correlation with volcanic features.•Variations in intrusion degassing ...could produce observed density heterogeneities.
Floor-fractured craters are a class of lunar crater hypothesized to form in response to the emplacement of a shallow magmatic intrusion beneath the crater floor. The emplacement of a shallow magmatic body should result in a positive Bouguer anomaly relative to unaltered complex craters, a signal which is observed for the average Bouguer anomaly interior to the crater walls. We observe the Bouguer anomaly of floor-fractured craters on an individual basis using the unfiltered Bouguer gravity solution from GRAIL and also a degree 100–600 band-filtered Bouguer gravity solution. The low-magnitude of anomalies arising from shallow magmatic intrusions makes identification using unfiltered Bouguer gravity solutions inconclusive. The observed anomalies in the degree 100–600 Bouguer gravity solution are spatially heterogeneous, although there is spatial correlation between volcanic surface morphologies and positive Bouguer anomalies. We interpret these observations to mean that the spatial heterogeneity observed in the Bouguer signal is the result of variable degrees of magmatic degassing within the intrusions.
Ice-giant-sized planets are the most common type of observed exoplanet, yet the two ice giants in our own solar system (Uranus and Neptune) are the least explored class of planet, having only been ...observed through ground-based observations and a single flyby each by Voyager 2 approximately 30 years ago. These single flybys were unable to characterize the spatial and temporal variability in ice giant magnetospheres, some of the most odd and intriguing magnetospheres in the solar system. They also offered only limited constraints on the internal structure of ice giants; understanding the internal structure of a planet is important for understanding its formation and evolution. The most recent planetary science Decadal Survey by the U.S. National Academy of Sciences, “Vision and Voyages for Planetary Science in the Decade 2013–2022,” identified the ice giant Uranus as the third highest priority for a Flagship mission in the decade 2013–2022. However, in the event that NASA or another space agency is unable to fly a Flagship-class mission to an ice giant in the next decade, this paper presents a mission concept for a focused, lower cost Uranus orbiter called OCEANUS (Origins and Composition of the Exoplanet Analog Uranus System). OCEANUS would increase our understanding of the interior structure of Uranus, its magnetosphere, and how its magnetic field is generated. These goals could be achieved with just a magnetometer and the spacecraft's radio system. This study shows that several of the objectives outlined by the Decadal Survey, including one of the two identified as highest priority, are within reach for a New-Frontiers-class mission.
•OCEANUS would be a New-Frontiers-class Uranus orbiter.•It would address 4 of the Decadal Survey objectives for a Uranus Flagship mission.•It would investigate Uranus' interior structure, magnetic field, and magnetosphere.
Abstract
The Aristarchus plateau represents one of the most complex volcanic provinces on the lunar surface and is host to the largest pyroclastic deposit on the Moon. Lunar pyroclastic deposits ...offer a window into the Moon’s interior and represent a valuable resource to support a sustained human presence. We present a new analysis of the Aristarchus pyroclastic deposit using Mini-RF bistatic radar data at wavelengths of 4.2 and 12.6 cm. Building on previous Earth-based Arecibo Observatory radar studies at 12.6 and 70 cm, we place further constraints on the spatial extent of the pyroclastic deposit and investigate the clast size distribution and provenance of foreign material distributed within the formation. Concentrations of blocky material >0.5 cm in diameter and suspended within the upper decimeters of the pyroclastic deposit are associated with potential buried mare flows along the rim of Vallis Schröteri and discrete pockets of primary material ejected by the Aristarchus impact. Unraveling the deposit from nonpyroclastic materials and the surrounding landscape creates new constraints with which to reconstruct the volcanic history of the region. From a future mission perspective, the identification of primary Aristarchus material distributed across the plateau offers an opportunity to sample diverse volcanic lithologies within an area that could be sampled by a single Commercial Lunar Payload Services mission. In terms of lunar resource in situ utilization, such ejected material also represents a contaminant; thus, radar data provide an invaluable tool to identify pristine pyroclastic material for mission planners.
The multicenter randomized controlled COBALT trial demonstrated that ultrasound-guided breast-conserving surgery (USS) results in a significant reduction of margin involvement (3.1% vs. 13%) and ...excision volumes compared to palpation-guided surgery (PGS). The aim of the present study was to determine long term oncological and patient-reported outcomes including quality of life (QoL), together with their progress over time.
134 patients with T1-T2 breast cancer were randomized to USS (N = 65) or PGS (N = 69). Cosmetic outcomes were assessed with the Breast Cancer Conservative Treatment cosmetic results (BCCT.core) software, panel-evaluation and patient self-evaluation on a 4-point Likert-scale. QoL was measured using the EORTC QLQ-C30/-BR23 questionnaire.
No locoregional recurrences were reported after mean follow-up of 41 months. Seven patients (5%) developed distant metastatic disease (USS 6.3%, PGS 4.4%, p = 0.466), of whom six died of disease (95.5% overall survival). USS achieved better cosmetic outcomes compared to PGS, with poor outcomes of 11% and 21% respectively, a result mainly attributable to mastectomies due to involved margins following PGS. There was no difference after 1 and 3 years in cosmetic outcome. Dissatisfied patients included those with larger excision volumes, additional local therapies and worse QoL. Patients with poor/fair cosmetic outcomes scored significantly lower on aspects of QoL, including breast-symptoms, body image and sexual enjoyment.
By significantly reducing positive margin status and lowering resection volumes, USS improves the rate of good cosmetic outcomes and increases patient-satisfaction. Considering the large impact of cosmetic outcome on QoL, USS has great potential to improve QoL following breast-conserving therapy.
Abstract
Quantifying the volumes and geologic nature of lunar volcanic eruptions is important for constraining the thermal and geologic evolution of the Moon. Cryptomaria are effusive, basaltic lava ...flows on the Moon that were subsequently buried, and therefore hidden, by higher-albedo basin and crater ejecta. Radar offers the ability to probe the subsurface for geologic units not otherwise apparent at the surface. We use Arecibo/Green Bank Observatory and Lunar Reconnaissance Orbiter Mini-RF radar data sets to characterize maria and cryptomaria within the Schiller–Schickard region. We find significant variability in the radar backscatter across the region that does not correspond to previously mapped boundaries of maria and cryptomaria in the literature. We use the characteristic low backscatter (due to the attenuating nature in radio waves of some basaltic minerals) to analyze the distribution of cryptomaria. We use the reduction in radar backscatter to estimate burial depths of cryptomaria across the area. We present a new map of Schiller–Schickard cryptomaria and the local variability in the thicknesses of the light plains that bury the basalts. We find burial depths ranging from >100 m in the deepest areas to just a few to tens of meters in areas with shallow cryptomaria (particularly prominent in the southeast). These areas are generally contiguous with maria, allowing us to track mare lava flow units into the subsurface at mare/highland margins. We propose that ∼67% of the region contains surface or buried basaltic volcanism, which represents over twice (2.7× increase) the areal extent of cryptomaria reported in previous studies.
Both Earth and the Moon share a common history regarding the epoch of large basin formation, though only the lunar geologic record preserves any appreciable record of this Late Heavy Bombardment. The ...emergence of Earth's first life is approximately contemporaneous with the Late Heavy Bombardment; understanding the latter informs the environmental conditions of the former, which are likely necessary to constrain the mechanisms of abiogenesis. While the relative formation time of most of the Moon's large basins is known, the absolute timing is not. The timing of Crisium Basin's formation is one of many important events that must be constrained and would require identifying and dating impact melt formed in the Crisium event. To inform a future lunar sample dating mission, we thus characterized possible outcrops of impact melt. We determined that several mare lava‐embayed kipukas could contain impact melt, though the rim and central peaks of the partially lava‐flooded Yerkes Crater likely contain the most pure and intact Crisium impact melt. It is here where future robotic and/or human missions could confidently add a key missing piece to the puzzle of the combined issues of early Earth‐Moon bombardment and the emergence of life.
Plain Language Summary
How could life get started on Earth nearly four billion years ago if our planet was constantly being impacted by asteroids and comets? While we do not yet know, we are starting to piece together parts of the answer. Earth's largest impact basins are long gone because of our planet's active geology, life, and flowing water. But the Moon's big craters are well preserved. The formation of those large basins melted lots of rocks, which then cooled; by collecting those rocks on future missions and figuring out how old they are, we can determine the timing of when large basins formed on the Moon and, by extension, on Earth. Crisium basin is one of those large basins that we need to get the age for. Most of the rock that was melted from this impact and then cooled is buried by much younger lava flows, but we believe that some of it was brought up when the crater Yerkes formed on top of Crisium. The central mountain of Yerkes Crater is where we believe future robots and/or astronauts should go to collect once‐molten rock and figure out how old it and the basin are.
Key Points
Relatively pure impact melt from Crisium Basin is exposed in the central peaks of Yerkes Crater
Diluted Crisium impact melt may be exposed in some previously identified kipukas in Crisium
Radiogenic dating of impact melt exposed in Yerkes' central peak during a future mission would yield the age of the Crisium impact event
Objective
To assess the costs of labour induction with oral misoprostol versus Foley catheter.
Design
Economic evaluation alongside a randomised controlled trial.
Setting
Obstetric departments of six ...tertiary and 23 secondary care hospitals in the Netherlands.
Population
Women with a viable term singleton pregnancy in cephalic presentation, intact membranes, an unfavourable cervix (Bishop score <6) without a previous caesarean section, were randomised for labour induction with oral misoprostol (n = 924) or Foley catheter (n = 921).
Methods
We performed economic analysis from a hospital perspective. We estimated direct medical costs associated with healthcare utilisation from randomisation until discharge. The robustness of our findings was evaluated in sensitivity analyses.
Main outcome measures
Mean costs and differences were calculated per women induced with oral misoprostol or Foley catheter.
Results
Mean costs per woman in the oral misoprostol group and Foley catheter group were €4470 versus €4158, respectively mean difference €312, 95% confidence interval (CI) –€508 to €1063. Multiple sensitivity analyses did not change these conclusions. However, if cervical ripening for low‐risk pregnancies in the Foley catheter group was carried out in an outpatient setting, with admittance to labour ward only at start of active labour, the difference would be €4470 versus €3489, respectively (mean difference €981, 95% CI €225–1817).
Conclusions
Oral misoprostol and Foley catheter generate comparable costs. Cervical ripening outside labour ward with a Foley catheter could potentially save almost €1000 per woman.
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Oral misoprostol or Foley catheter for induction of labour generates comparable costs.
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Oral misoprostol or Foley catheter for induction of labour generates comparable costs.
Abstract Background Tuberous sclerosis complex is an autosomal dominant disorder predisposing to the development of benign lesions in different body organs, mainly in the brain, kidney, liver, skin, ...heart, and lung. Subependymal giant cell astrocytomas are characteristic brain tumors that occur in 10% to 20% of tuberous sclerosis complex patients and are almost exclusively related to tuberous sclerosis complex. Subependymal giant cell astrocytomas usually grow slowly, but their progression ultimately leads to the occlusion of the foramen of Monro, with subsequent increased intracranial pressure and hydrocephalus, thus necessitating intervention. During recent years, secondary to improved understanding in the biological and genetic basis of tuberous sclerosis complex, mammalian target of rapamycin inhibitors have been shown to be effective in the treatment of subependymal giant cell astrocytomas, becoming an alternative therapeutic option to surgery. Methods In June 2012, an International Tuberous Sclerosis Complex Consensus Conference was convened, during which an expert panel revised the diagnostic criteria and considered treatment options for subependymal giant cell astrocytomas. This article summarizes the subpanel's recommendations regarding subependymal giant cell astrocytomas. Conclusions Mammalian target of rapamycin inhibitors have been shown to be an effective treatment of various aspects of tuberous sclerosis complex, including subependymal giant cell astrocytomas. Both mammalian target of rapamycin inhibitors and surgery have a role in the treatment of subependymal giant cell astrocytomas. Various subependymal giant cell astrocytoma–related conditions favor a certain treatment.
Trigonal tellurium, a small-gap semiconductor with pronounced magneto-electric and magneto-optical responses, is among the simplest realizations of a chiral crystal. We have studied by spin- and ...angle-resolved photoelectron spectroscopy its unconventional electronic structure and unique spin texture. We identify Kramers–Weyl, composite, and accordionlike Weyl fermions, so far only predicted by theory, and show that the spin polarization is parallel to the wave vector along the lines in k space connecting high-symmetry points. Our results clarify the symmetries that enforce such spin texture in a chiral crystal, thus bringing new insight in the formation of a spin vectorial field more complex than the previously proposed hedgehog configuration. Our findings thus pave the way to a classification scheme for these exotic spin textures and their search in chiral crystals.
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