OCAMS: The OSIRIS-REx Camera Suite Rizk, B.; Drouet d’Aubigny, C.; Golish, D. ...
Space science reviews,
02/2018, Letnik:
214, Številka:
1
Journal Article
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The OSIRIS-REx Camera Suite (OCAMS) will acquire images essential to collecting a sample from the surface of Bennu. During proximity operations, these images will document the presence of satellites ...and plumes, record spin state, enable an accurate model of the asteroid’s shape, and identify any surface hazards. They will confirm the presence of sampleable regolith on the surface, observe the sampling event itself, and image the sample head in order to verify its readiness to be stowed. They will document Bennu’s history as an example of early solar system material, as a microgravity body with a planetesimal size-scale, and as a carbonaceous object. OCAMS is fitted with three cameras. The MapCam will record color images of Bennu as a point source on approach to the asteroid in order to connect Bennu’s ground-based point-source observational record to later higher-resolution surface spectral imaging. The SamCam will document the sample site before, during, and after it is disturbed by the sample mechanism. The PolyCam, using its focus mechanism, will observe the sample site at sub-centimeter resolutions, revealing surface texture and morphology. While their imaging requirements divide naturally between the three cameras, they preserve a strong degree of functional overlap. OCAMS and the other spacecraft instruments will allow the OSIRIS-REx mission to collect a sample from a microgravity body on the same visit during which it was first optically acquired from long range, a useful capability as humanity reaches out to explore near-Earth, Main-Belt and Jupiter Trojan asteroids.
•Disparities in receipt of pharmacotherapy for alcohol use disorders exist across race.•Black patients are less likely than white to receive effective pharmacotherapies.•Efforts are needed to ...increase alcohol use disorder (AUD) pharmacotherapy across populations; targeted efforts may be needed.
Pharmacologic treatment is recommended for alcohol use disorders (AUD), but most patients do not receive it. Although racial/ethnic minorities have greater AUD consequences than whites, whether AUD medication receipt varies across race/ethnicity is unknown. We evaluate this in a national sample.
Electronic health records data were extracted for all black, Hispanic, and/or white patients who received care at the U.S. Veterans Health Administration (VA) during Fiscal Year 2012 and had a documented AUD diagnosis. Mixed effects regression models, with a random effect for facility, determined the likelihood of receiving AUD pharmacotherapy (acamprosate, disulfiram, topirimate or oral or injectable naltrexone ≤180days after AUD diagnosis) for black and Hispanic patients relative to white patients. Models were unadjusted and then adjusted for patient- and facility-level factors.
297,506 patients had AUD; 26.4% were black patients, 7.1% were Hispanic patients and 66.5% were white patients; 5.1% received AUD medications. Before adjustment, black patients were less likely than white Odds Ratio (OR) 0.77; 95% Confidence Interval (CI) 0.75 −0.82; (p<0.001), while Hispanic patients were more likely than white (OR 1.09; 95% CI 1.01–1.16) to receive AUD medications. After adjustment, black patients remained less likely than white to receive AUD medications (OR 0.68; 95% CI 0.65–0.71; p<0.0001); no difference between Hispanic and white patients was observed (OR 0.94; 95% CI 0.87–1.00; p=0.07).
In this national study of patients with AUD, blacks were less likely to receive AUD medications than whites. Future research is needed to identify why these disparities exist.
The Met Office Unified Model develops a systematic error consisting of a large high‐pressure bias over the North Pole. The error begins to develop early in numerical weather prediction forecasts and ...is the leading large‐scale circulation error in the model's climatological mean, with implications for principle circulation regimes and blocking. The cause of the error is investigated using a variety of diagnostic techniques, including analysis of a perturbed parameter ensemble for the model, evaluation of changes in both weather and climate simulations to minimise the risk of introducing compensating errors, and detailed comparisons with another model. A reduction in this systematic error is achieved through an overall reduction in the near‐surface drag; however, to accomplish this without affecting forecast predictability adversely, a redistribution of the drag is required between the roughness from vegetation in the land‐surface scheme, the near‐surface drag from the orographic gravity‐wave drag scheme, the turbulent orographic form drag, and the resolved drag (through changing the orographic filtering). A modest reduction in the climatological bias is achieved, along with a reduction in bias and improved predictability of near‐surface winds.
The Met Office Unified model develops a large high surface pressure bias and associated geopotential height error over the Arctic (figure shows the climatological bias against ERA‐Interim for a) PMSL, b) geopotential height (m)). The cause of the error is investigated and a redistribution of near‐surface drag between parametrization schemes is found to be required
Objective
To examine the management and long‐term outcomes of transverse vaginal septae.
Design
Observational study with cross‐sectional and retrospective arms.
Setting
Tertiary referral centre ...specialising in Müllerian anomalies.
Population
Forty‐six girls and women with a transverse vaginal septum.
Methods
Data from medical records of all cases (1998–2013) of transverse vaginal septae were collected and reviewed. Patients over 16 years of age also completed a questionnaire.
Main outcome measures
Presentation, examination findings, investigations, surgery, and long‐term reproductive outcomes.
Results
The septae in the study were described as follows: 61% (95% CI 0.46–0.74) were imperforate, and presented with obstructed menstruation; 39% (95% CI 0.26–0.54) were perforate, and presented with a variety of concerns; 72% (95% CI 0.57–0.83) were low, 22% (95% CI 0.12–0.36) were mid‐vaginal, and 6% (95% CI 0.02–0.18) were high; 33% were managed via an abdominoperineal approach, 59% were managed via a vaginal approach, and 6% had laparoscopic resection (one patient did not have surgery); 11% (95% CI 0.05–0.23) of patients presented with reobstruction, all following abdominoperineal vaginoplasty; 7% presented with vaginal stenosis, two following vaginal resection and one following the abdominoperineal approach; 61% of questionnaires were returned. These results showed that 22/23 patients were menstruating and one had a hysterectomy, 74% had been sexually active, 35% had dyspareunia, and 36% complained of dysmenorrhoea. There were seven pregnancies, with one termination and six live births, all following the vaginal excision of a transverse vaginal septum.
Conclusions
Transverse vaginal septae resected vaginally or laparoscopically have low complication rates and good long‐term outcomes. Complex septae require more extensive surgery, with an increased risk of complications.
Hypothalamic AgRP and POMC neurons are conventionally viewed as the yin and yang of the body's energy status, since they act in an opposite manner to modulate appetite and systemic energy metabolism. ...However, although AgRP neurons' functions are comparatively well understood, a unifying theory of how POMC neuronal cells operate has remained elusive, probably due to their high level of heterogeneity, which suggests that their physiological roles might be more complex than initially thought. In this Perspective, we propose a conceptual framework that integrates POMC neuronal heterogeneity with appetite regulation, whole-body metabolic physiology and the development of obesity. We highlight emerging evidence indicating that POMC neurons respond to distinct combinations of interoceptive signals and food-related cues to fine-tune divergent metabolic pathways and behaviours necessary for survival. The new framework we propose reflects the high degree of developmental plasticity of this neuronal population and may enable progress towards understanding of both the aetiology and treatment of metabolic disorders.
X-ray free-electron lasers enable the investigation of the structure and dynamics of diverse systems, including atoms, molecules, nanocrystals and single bioparticles, under extreme conditions. Many ...imaging applications that target biological systems and complex materials use hard X-ray pulses with extremely high peak intensities (exceeding 10
watts per square centimetre). However, fundamental investigations have focused mainly on the individual response of atoms and small molecules using soft X-rays with much lower intensities. Studies with intense X-ray pulses have shown that irradiated atoms reach a very high degree of ionization, owing to multiphoton absorption, which in a heteronuclear molecular system occurs predominantly locally on a heavy atom (provided that the absorption cross-section of the heavy atom is considerably larger than those of its neighbours) and is followed by efficient redistribution of the induced charge. In serial femtosecond crystallography of biological objects-an application of X-ray free-electron lasers that greatly enhances our ability to determine protein structure-the ionization of heavy atoms increases the local radiation damage that is seen in the diffraction patterns of these objects and has been suggested as a way of phasing the diffraction data. On the basis of experiments using either soft or less-intense hard X-rays, it is thought that the induced charge and associated radiation damage of atoms in polyatomic molecules can be inferred from the charge that is induced in an isolated atom under otherwise comparable irradiation conditions. Here we show that the femtosecond response of small polyatomic molecules that contain one heavy atom to ultra-intense (with intensities approaching 10
watts per square centimetre), hard (with photon energies of 8.3 kiloelectronvolts) X-ray pulses is qualitatively different: our experimental and modelling results establish that, under these conditions, the ionization of a molecule is considerably enhanced compared to that of an individual heavy atom with the same absorption cross-section. This enhancement is driven by ultrafast charge transfer within the molecule, which refills the core holes that are created in the heavy atom, providing further targets for inner-shell ionization and resulting in the emission of more than 50 electrons during the X-ray pulse. Our results demonstrate that efficient modelling of X-ray-driven processes in complex systems at ultrahigh intensities is feasible.
Perrault syndrome is a rare autosomal recessive disorder characterized by sensorineural hearing loss (SNHL) in both sexes and primary ovarian insufficiency in 46, XX karyotype females. Biallelic ...variants in five genes are reported to be causative: HSD17B4, HARS2, LARS2, CLPP and C10orf2. Here we present eight families affected by Perrault syndrome. In five families we identified novel or previously reported variants in HSD17B4, LARS2, CLPP and C10orf2. The proband from each family was whole exome sequenced and variants confirmed by Sanger sequencing. A female was compound heterozygous for a known, p.(Gly16Ser) and novel, p.(Val82Phe) variant in D‐bifunctional protein (HSD17B4). A family was homozygous for mitochondrial leucyl aminocyl tRNA synthetase (mtLeuRS) (LARS2) p.(Thr522Asn), previously associated with Perrault syndrome. A further family was compound heterozygous for mtLeuRS, p.(Thr522Asn) and a novel variant, p.(Met117Ile). Affected individuals with LARS2 variants had low frequency SNHL, a feature previously described in Perrault syndrome. A female with significant neurological disability was compound heterozygous for p.(Arg323Gln) and p.(Asn399Ser) variants in Twinkle (C10orf2). A male was homozygous for a novel variant in CLPP, p.(Cys144Arg). In three families there were no putative pathogenic variants in these genes confirming additional disease‐causing genes remain unidentified. We have expanded the spectrum of disease‐causing variants associated with Perrault syndrome.
We study atmospheric escape from Mars during solar wind pressure pulses. During the solar minimum of 2007–08 we have observed 41 high pressure events, which are predominantly identified as corotating ...interaction regions (CIR) while a few are coronal mass ejections (CME), in data from the Advanced Composition Explorer (ACE) upstream of the Earth. 36 of these events are also identified using Mars Express (MEX) data at Mars. We use MEX measurements at Mars to compare the antisunward fluxes of heavy planetary ions during the passage of these pulses to the fluxes during quiet solar wind conditions. The ion fluxes are observed to increase by a factor of ∼2.5, on average. Hence, a third of the total outflow from Mars takes place during ∼15% of the time, when a solar wind pressure pulse impacts on the planet. This can have important consequences for the total time‐integrated outflow of plasma from Mars.
Magnetostrictive materials transduce magnetic and mechanical energies and when combined with piezoelectric elements, evoke magnetoelectric transduction for high-sensitivity magnetic field sensors and ...energy-efficient beyond-CMOS technologies. The dearth of ductile, rare-earth-free materials with high magnetostrictive coefficients motivates the discovery of superior materials. Fe
Ga
alloys are amongst the highest performing rare-earth-free magnetostrictive materials; however, magnetostriction becomes sharply suppressed beyond x = 19% due to the formation of a parasitic ordered intermetallic phase. Here, we harness epitaxy to extend the stability of the BCC Fe
Ga
alloy to gallium compositions as high as x = 30% and in so doing dramatically boost the magnetostriction by as much as 10x relative to the bulk and 2x larger than canonical rare-earth based magnetostrictors. A Fe
Ga
- Pb(Mg
Nb
)O
-PbTiO
(PMN-PT) composite magnetoelectric shows robust 90° electrical switching of magnetic anisotropy and a converse magnetoelectric coefficient of 2.0 × 10
s m
. When optimally scaled, this high coefficient implies stable switching at ~80 aJ per bit.
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