Mass changes of the Greenland Ice Sheet resolved by drainage system regions were derived from a local mass concentration analysis of NASA-Deutsches Zentrum für Luftund Raumfahrt Gravity Recovery and ...Climate Experiment (GRACE mission) observations. From 2003 to 2005, the ice sheet lost 101 ± 16 gigaton/year, with a gain of 54 gigaton/year above 2000 meters and a loss of 155 gigaton/year at lower elevations. The lower elevations show a large seasonal cycle, with mass losses during summer melting followed by gains from fall through spring. The overall rate of loss reflects a considerable change in trend (-113 ± 17 gigaton/year) from a near balance during the 1990s but is smaller than some other recent estimates.
Metal dyshomeostasis is associated with neurodegenerative disorders, cancers and vascular disease. We report the effects of age (range: 3 to 18 months) on regional copper, iron and zinc levels in the ...brain of the C57BL/6 mouse, a widely used inbred strain with a permissive background allowing maximal expression of mutations in models that recapitulate these disorders. We present formulae that can be used to determine regional brain metal concentrations in the C57BL/6 mouse at any age in the range of three to eighteen months of life. Copper levels in the C57BL/6 mouse adult brain were highest in the striatum and cerebellum and increased with age, excepting the cortex and hippocampus. Regional iron levels increased linearly with age in all brain regions, while regional zinc concentrations became more homogeneous with age. Knockdown of the copper transporter Ctr1 reduced brain copper, but not iron or zinc, concentrations in a regionally-dependent manner. These findings demonstrate biometals in the brain change with age in a regionally-dependent manner. These data and associated formulae have implications for improving design and interpretation of a wide variety of studies in the C57BL/6 mouse.
•Brain biometals change with age and are linked to several neurological diseases.•Animal models of these disorders are commonly based on the C57BL/6 mouse.•Brain iron, copper and zinc levels are regionally altered with age in C57BL/6 mouse.•Formulae allow calculation of regional brain metal levels between 3-18 months of age.•Comparison with human brain allows for improved study design and interpretation.
Objective
To estimate the prevalence and incidence of endometriosis among Australian women.
Design
Population‐based cohort study linked to administrative health records.
Setting
Secondary analysis of ...seven surveys collected between 2000 and 2018 from a population‐based cohort study.
Population
A total of 13 508 Australian women, born 1973–78, from a prospective cohort study of 14 247 women conducted between 1996 and 2018.
Methods
During 2000 and 2018, self‐reported longitudinal survey data were linked to three administrative health databases to separately identify women with clinically confirmed or suspected endometriosis across the multiple data sources.
Main outcome measures
Prevalence and incidence of clinically confirmed endometriosis in the cohort were first estimated using national hospital data. Data were then combined with other administrative health databases and the survey data to capture all clinically confirmed and suspected diagnoses of endometriosis.
Results
The cumulative prevalence of clinically confirmed endometriosis was 6.0% (95% CI 5.8–6.2%) by age 40–44 years. The cumulative prevalence increased to 11.4% (95% CI 11.1–11.7%) when adding diagnoses of clinically suspected endometriosis. Age‐specific incidence estimates peaked to 6 per 1000 person‐years at age 30–34 years.
Conclusions
Among 13 508 Australian women followed for 20 years, one in nine women had clinically confirmed or suspected endometriosis by the age of 44, with most diagnosed during their early thirties. Endometriosis is a significant public health issue requiring increased surveillance, clinical awareness and management. Efforts to expand knowledge on the aetiology of the disease and optimal methods for disease management are crucial to women's health.
Tweetable
In a national study of 13 508 Australian women, one in nine women were diagnosed with endometriosis by age 44.
Tweetable
In a national study of 13 508 Australian women, one in nine women were diagnosed with endometriosis by age 44.
A spherical harmonic solution of the Mars gravity field to degree and order 80, Goddard Mars Model 2B (GMM‐2B), has been developed using X band tracking data of Mars Global Surveyor (MGS) from ...October 1997 to February 2000 and altimeter crossovers formed from the Mars Orbiter Laser Altimeter (MOLA) data between March and December 1999. During the mapping mission, MGS was located in a near‐polar (92.9° inclination) and near‐circular orbit at a mean altitude of 400 km. The tracking data from this orbit provide a detailed, global, and high resolution view of the gravity field of Mars. Mars gravity solutions are stable to 60×60 even without application of a Kaula power law constraint. The Valles Marineris is resolved distinctly with lows reaching −450 mGals. Olympus Mons and its aureole are both separately resolved, and the volcano has a peak anomaly of 2950 mGals. The global correlation of the GMM‐2B gravity coefficients with MOLA‐derived topography is 0.78 through degree 60, and the correlation remains above 0.6 through degree 62. The global gravity anomaly error predicted from the GMM‐2B error covariance through 60×60 is 11 mGal. The global geoid error from GMM‐2B through 60×60 is 1.8 m. MGS orbit quality using GMM‐2B, as measured by overlapping orbital arcs, is 1 m in the radial direction and 10 m in total position.
We investigate fast-pulse switching of in-plane-magnetized magnetic tunnel junctions (MTJs) within 3-terminal devices in which spin-transfer torque is applied to the MTJ by the giant spin Hall ...effect. We measure reliable switching, with write error rates down to 10–5, using current pulses as short as just 2 ns in duration. This represents the fastest reliable switching reported to date for any spin-torque-driven magnetic memory geometry and corresponds to a characteristic time scale that is significantly shorter than predicted possible within a macrospin model for in-plane MTJs subject to thermal fluctuations at room temperature. Using micromagnetic simulations, we show that in the three-terminal spin-Hall devices the Oersted magnetic field generated by the pulse current strongly modifies the magnetic dynamics excited by the spin-Hall torque, enabling this unanticipated performance improvement. Our results suggest that in-plane MTJs controlled by Oersted-field-assisted spin-Hall torque are a promising candidate for both cache memory applications requiring high speed and for cryogenic memories requiring low write energies.
The differences between mass concentration (mas con) parameters and standard Stokes coefficient parameters in the recovery of gravity infonnation from gravity recovery and climate experiment (GRACE) ...intersatellite K-band range rate data are investigated. First, mascons are decomposed into their Stokes coefficient representations to gauge the range of solutions available using each of the two types of parameters. Next, a direct comparison is made between two time series of unconstrained gravity solutions, one based on a set of global equal area mascon parameters (equivalent to 4deg x 4deg at the equator), and the other based on standard Stokes coefficients with each time series using the same fundamental processing of the GRACE tracking data. It is shown that in unconstrained solutions, the type of gravity parameter being estimated does not qualitatively affect the estimated gravity field. It is also shown that many of the differences in mass flux derivations from GRACE gravity solutions arise from the type of smoothing being used and that the type of smoothing that can be embedded in mas con solutions has distinct advantages over postsolution smoothing. Finally, a 1 year time series based on global 2deg equal area mascons estimated every 10 days is presented.
The GRACE mission is designed to monitor mass flux on the Earth's surface at one month and high spatial resolution through the estimation of monthly gravity fields. Although this approach has been ...largely successful, information at submonthly time scales can be lost or even aliased through the estimation of static monthly parameters. Through an analysis of the GRACE data residuals, we show that the fundamental temporal and spatial resolution of the GRACE data is 10 days and 400 km. We present an approach similar in concept to altimetric methods that recovers submonthly mass flux at a high spatial resolution. Using 4° × 4° blocks at 10‐day intervals, we estimate the mass of surplus or deficit water over a 52° × 60° grid centered on the Amazon basin for July 2003. We demonstrate that the recovered signals are coherent and correlate well with the expected hydrological signal.
We present the first direct and unbiased measurement of the evolution of the dust mass function of galaxies over the past 5 billion years of cosmic history using data from the Science Demonstration ...Phase of the Herschel-Astrophysical Terahertz Large Area Survey (Herschel-ATLAS). The sample consists of galaxies selected at 250
m which have reliable counterparts from the Sloan Digital Sky Survey (SDSS) at z < 0.5, and contains 1867 sources. Dust masses are calculated using both a single-temperature grey-body model for the spectral energy distribution and also a model with multiple temperature components. The dust temperature for either model shows no trend with redshift. Splitting the sample into bins of redshift reveals a strong evolution in the dust properties of the most massive galaxies. At z= 0.4-0.5, massive galaxies had dust masses about five times larger than in the local Universe. At the same time, the dust-to-stellar mass ratio was about three to four times larger, and the optical depth derived from fitting the UV-sub-mm data with an energy balance model was also higher. This increase in the dust content of massive galaxies at high redshift is difficult to explain using standard dust evolution models and requires a rapid gas consumption time-scale together with either a more top-heavy initial mass function (IMF), efficient mantle growth, less dust destruction or combinations of all three. This evolution in dust mass is likely to be associated with a change in overall interstellar medium mass, and points to an enhanced supply of fuel for star formation at earlier cosmic epochs.
Abstract
Understanding how galaxies quench their star formation is crucial for studies of galaxy evolution. Quenching is related to a decrease of cold gas. In the first paper we showed that the dust ...removal timescale in early-type galaxies (ETGs) is about 2.5 Gyr. Here we present carbon monoxide and 21 cm hydrogen line observations of these galaxies and measure the timescale of removal of the cold interstellar medium (ISM). We find that all the cold ISM components (dust and molecular and atomic gas) decline at similar rates. This allows us to rule out a wide range of potential ISM-removal mechanisms (including starburst-driven outflows, astration, or a decline in the number of asymptotic giant branch stars), and artificial effects like the stellar mass–age correlation, environmental influence, mergers, and selection bias, leaving ionization by evolved low-mass stars and ionization/outflows by Type Ia supernovae or active galactic nuclei as viable mechanisms. We also provide evidence for an internal origin of the detected ISMs. Moreover, we find that the quenching of star formation in these galaxies cannot be explained by a reduction in the gas amount alone, because the star formation rates (SFRs) decrease faster (on a timescale of about 1.8 Gyr) than the amount of cold gas. Furthermore, the star formation efficiency (SFE) of the ETGs (
SFE
≡
SFR
/
M
H
2
) is lower than that of star-forming galaxies, whereas their gas mass fractions (
f
H
2
≡
M
H
2
/
M
*
) are normal. This may be explained by the stabilization of gas against fragmentation, for example due to morphological quenching, turbulence, or magnetic fields.
We present the results on precision orbit determination from the radio science investigation of the Lunar Reconnaissance Orbiter (LRO) spacecraft. We describe the data, modeling and methods used to ...achieve position knowledge several times better than the required 50–100 m (in total position), over the period from 13 July 2009 to 31 January 2011. In addition to the near-continuous radiometric tracking data, we include altimetric data from the Lunar Orbiter Laser Altimeter (LOLA) in the form of crossover measurements, and show that they strongly improve the accuracy of the orbit reconstruction (total position overlap differences decrease from ~70 m to ~23 m). To refine the spacecraft trajectory further, we develop a lunar gravity field by combining the newly acquired LRO data with the historical data. The reprocessing of the spacecraft trajectory with that model shows significantly increased accuracy (~20 m with only the radiometric data, and ~14 m with the addition of the altimetric crossovers). LOLA topographic maps and calibration data from the Lunar Reconnaissance Orbiter Camera were used to supplement the results of the overlap analysis and demonstrate the trajectory accuracy.
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