Establishing a sustainable vegetation cover is one of the most important steps in progressive rehabilitation and final closure of ore-processing residues and tailings facilities. Sustainable ...rehabilitation partly depends on establishing and maintaining a supply of plant-available nutrients, but few long term field studies demonstrating the success or failure of rehabilitation of degraded land such as mineral processing tailings have been reported. Bauxite-processing residues are a highly sodic, highly alkaline, nutrient-poor by-product generated from alumina extraction, and pose many challenges for successful rehabilitation. This study investigated long term performance of rehabilitation established on bauxite-processing residue storage areas (RSAs) by comparing the nutrient content of the vegetation cover with nutrient concentrations in the underlying residue sand. Five plant species having diverse physiology were selected from rehabilitation varying in age from 1 to 10 years old; these being: Hardenbergia comptoniana – a vigorous growing legume ground cover/creeper), Acacia cochlearis and A. rostellifera - legume shrubs tolerant of sandy, alkaline conditions, Grevillea crithmifolia - a drought-tolerant proteaceous shrub tolerant of alkaline soil, and Spyridium globulosum - a robust, fast-growing shrub, commonly found on alkaline coastal soils. Gypsum incorporation reduced the pH and soluble aluminium levels in residue sand, but also acted as a long-term source of nutrients for the vegetation cover. Legume species contained more nitrogen than non-legumes (2.5% N and 1.5% N, respectively), and decomposition of surface litter increased organic carbon and total and mineral nitrogen contents of the residue sand over time. Nutrient cycling maintained a supply of macro- and micro- nutrients for the vegetation cover, and 10-year old rehabilitation exhibited characteristics similar to an analogue site. This study highlighted the importance of organic matter accumulation, developing a functional microbial community, and a diverse plant species mix on transforming the residue sand characteristics and encouraging nutrient cycling as key mechanisms for establishing a sustainable vegetation cover and functional ecosystem on residue sand embankments.
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•Bauxite residue rehabilitation is afflicted by high pH, sodicity and poor nutrient content.•Previous studies have been restricted by short monitoring timeframes.•Long term performance of vegetation on rehabilitated bauxite residue was assessed.•Organic carbon and total and mineral nitrogen contents of the rehabilitated residue increased over time.•10-year old rehabilitation exhibited characteristics similar to an analogue site.
BACKGROUND Polycystic ovary syndrome (PCOS) is considered to be the most common endocrine disorder in women of reproductive age, yet debate over appropriate diagnostic criteria and design limitations ...with sampling methodology have left some doubt as to the actual prevalence in the community. The objective of this study was to create a representative prevalence estimate of PCOS in the community under the National Institutes of Health (NIH) criteria and the more recent Rotterdam consensus criteria and Androgen Excess Society (AES) criteria. METHODS A retrospective birth cohort study was carried out in which 728 women born during 1973–1975 in a single maternity hospital were traced and interviewed in adulthood (age = 27–34 year; n = 728). Symptoms of PCOS (hyperandrogenism, menstrual dysfunction and polycystic ovaries) were identified by examination and the presence of polycystic ovaries in those that did not consent to the ultrasound were imputed. RESULTS The estimated prevalence of PCOS in this birth cohort using the NIH criteria was 8.7 ± 2.0% (with no need for imputation). Under the Rotterdam criteria, the prevalence was 11.9 ± 2.4% which increased to 17.8 ± 2.8% when imputed data were included. Under the AES recommendations, PCOS prevalence was 10.2 ± 2.2%, and 12.0 ± 2.4% with the imputed data. Of the women with PCOS, 68–69% did not have a pre-existing diagnosis. CONCLUSIONS The Rotterdam and AES prevalence estimates were up to twice that obtained with the NIH criteria in this, as well other prevalence studies. In addition, this study also draws attention to the issue of many women with PCOS in the community remaining undiagnosed.
The Solar Orbiter mission seeks to make connections between the physical processes occurring at the Sun or in the solar corona and the nature of the solar wind created by those processes which is ...subsequently observed at the spacecraft. The mission also targets physical processes occurring in the solar wind itself during its journey from its source to the spacecraft. To meet the specific mission science goals, Solar Orbiter will be equipped with both remote-sensing and in-situ instruments which will make unprecedented measurements of the solar atmosphere and the inner heliosphere. A crucial set of measurements will be provided by the Solar Wind Analyser (SWA) suite of instruments. This suite consists of an Electron Analyser System (SWA-EAS), a Proton and Alpha particle Sensor (SWA-PAS), and a Heavy Ion Sensor (SWA-HIS) which are jointly served by a central control and data processing unit (SWA-DPU). Together these sensors will measure and categorise the vast majority of thermal and suprathermal ions and electrons in the solar wind and determine the abundances and charge states of the heavy ion populations. The three sensors in the SWA suite are each based on the top hat electrostatic analyser concept, which has been deployed on numerous space plasma missions. The SWA-EAS uses two such heads, each of which have 360° azimuth acceptance angles and ±45° aperture deflection plates. Together these two sensors, which are mounted on the end of the boom, will cover a full sky field-of-view (FoV) (except for blockages by the spacecraft and its appendages) and measure the full 3D velocity distribution function (VDF) of solar wind electrons in the energy range of a few eV to ∼5 keV. The SWA-PAS instrument also uses an electrostatic analyser with a more confined FoV (−24° to +42° × ±22.5° around the expected solar wind arrival direction), which nevertheless is capable of measuring the full 3D VDF of the protons and alpha particles arriving at the instrument in the energy range from 200 eV/q to 20 keV/e. Finally, SWA-HIS measures the composition and 3D VDFs of heavy ions in the bulk solar wind as well as those of the major constituents in the suprathermal energy range and those of pick-up ions. The sensor resolves the full 3D VDFs of the prominent heavy ions at a resolution of 5 min in normal mode and 30 s in burst mode. Additionally, SWA-HIS measures 3D VDFs of alpha particles at a 4 s resolution in burst mode. Measurements are over a FoV of −33° to +66° × ±20° around the expected solar wind arrival direction and at energies up to 80 keV/e. The mass resolution (
m
/Δ
m
) is > 5. This paper describes how the three SWA scientific sensors, as delivered to the spacecraft, meet or exceed the performance requirements originally set out to achieve the mission’s science goals. We describe the motivation and specific requirements for each of the three sensors within the SWA suite, their expected science results, their main characteristics, and their operation through the central SWA-DPU. We describe the combined data products that we expect to return from the suite and provide to the Solar Orbiter Archive for use in scientific analyses by members of the wider solar and heliospheric communities. These unique data products will help reveal the nature of the solar wind as a function of both heliocentric distance and solar latitude. Indeed, SWA-HIS measurements of solar wind composition will be the first such measurements made in the inner heliosphere. The SWA data are crucial to efforts to link the in situ measurements of the solar wind made at the spacecraft with remote observations of candidate source regions. This is a novel aspect of the mission which will lead to significant advances in our understanding of the mechanisms accelerating and heating the solar wind, driving eruptions and other transient phenomena on the Sun, and controlling the injection, acceleration, and transport of the energetic particles in the heliosphere.
We study dwarf satellite galaxy quenching using observations from the Geha et al. NASA-Sloan Atlas/SDSS catalogue together with Λ cold dark matter cosmological simulations to facilitate selection and ...interpretation. We show that fewer than 30 per cent of dwarfs (M
⋆ ≃ 108.5 − 9.5 M⊙) identified as satellites within massive host haloes (M
host ≃ 1012.5 − 14 M⊙) are quenched, in spite of the expectation from simulations that half of them should have been accreted more than 6 Gyr ago. We conclude that whatever the action triggering environmental quenching of dwarf satellites, the process must be highly inefficient. We investigate a series of simple, one-parameter quenching models in order to understand what is required to explain the low quenched fraction and conclude that either the quenching time-scale is very long ( > 9.5 Gyr, a ‘slow starvation’ scenario) or that the environmental trigger is not well matched to accretion within the virial volume. We discuss these results in light of the fact that most
of the low-mass dwarf satellites in the Local Group are quenched, a seeming contradiction that could point to a characteristic mass scale for satellite quenching.
Context: The prevalence of obesity among women of childbearing age is increasing. Emerging evidence suggests that this has long-term adverse influences on offspring health.
Objective: The aim was to ...examine whether maternal body composition and gestational weight gain have persisting effects on offspring adiposity in early adulthood.
Design and Setting: The Motherwell birth cohort study was conducted in a general community in Scotland, United Kingdom.
Participants: We studied 276 men and women whose mothers’ nutritional status had been characterized in pregnancy. Four-site skinfold thicknesses, waist circumference, and body mass index (BMI), were measured at age 30 yr; sex-adjusted percentage body fat and fat mass index were calculated.
Main Outcome Measure: Indices of offspring adiposity at age 30 yr were measured.
Results: Percentage body fat was greater in offspring of mothers with a higher BMI at the first antenatal visit (rising by 0.35%/kg/m2; P < 0.001) and in offspring whose mothers were primiparous (difference, 1.5% in primiparous vs. multiparous; P = 0.03). Higher offspring percentage body fat was also independently associated with higher pregnancy weight gain (7.4%/kg/wk; P = 0.002). There were similar significant associations of increased maternal BMI, greater pregnancy weight gain, and parity with greater offspring waist circumference, BMI, and fat mass index.
Conclusions: Adiposity in early adulthood is influenced by prenatal influences independently of current lifestyle factors. Maternal adiposity, greater gestational weight, and parity all impact on offspring adiposity. Strategies to reduce the impact of maternal obesity and greater pregnancy weight gain on offspring future health are required.
Adiposity in early adulthood is influenced by prenatal influences including greater maternal pregnancy body mass index, gestational weight gain, and primiparity, independent of current lifestyle factors.
Background and Aims The objective of this study was to test the suitability of greenwaste biochar to aid nitrogen (N) retention in rehabilitated bauxite-processing residue sand (BRS). Methods Bauxite ...residue sand was collected from the Alcoa of Australia Pinjarra refinery. The pH of BRS was adjusted to values of 5, 7, 8 and 9 and subsequently amended with different rates (1,5,10 and 20 %, w/w) of greenwaste biochar. The loss of N via NH₃ volatilization following addition of di-ammonium phosphate (DAP) was determined using an acid trapping method. Results At low pH (5), increasing pH rather than adsorption capacity, resulting from biochar addition, caused greater losses of N through volatilization from BRS. In BRS with medium pH (7, 8), increasing adsorption capacity, induced by biochar addition, played the more dominant role in enhancing adsorption of NH₄⁺-N /NH₃-N and lowering NH₃ volatilization. In the BRS with high pH (9), the majority of NH₄⁺-N /NH₃-N pools was lost via NH₃ volatilization due to the strong acid-base reaction at this pH. Conclusions It is concluded that the interaction of changes in pH and adsorption capacity induced by greenwaste biochar addition affects the availability and dynamics of NH₄⁺-N /NH₃-N in BRS amended with DAP.
The effects of addition of a range of organic amendments (biosolids, spent mushroom compost, green waste compost and green waste-derived biochar), at two rates, on some key chemical, physical and ...microbial properties of bauxite-processing residue sand were studied in a laboratory incubation study. Levels of exchangeable cations were not greatly affected by additions of amendments but extractable P was increased significantly by mushroom and green waste composts and massively (i.e. from 11.8 to 966 mg P kg
−1) by biosolids applications. Levels of extractable NO
3
−–N were also greatly elevated by biosolids additions and there was a concomitant decrease in pH. Addition of all amendments decreased bulk density and increased mesoporosity, available water holding capacity and water retention at field capacity (−10 kPa), with the higher rate having a greater effect. Addition of biosolids, mushroom compost and green waste compost all increased soluble organic C, microbial biomass C, basal respiration and the activities of β-glucosidase, L-asparaginase and alkali phosphatase enzymes. The germination index of watercress grown in the materials was greatly reduced by biosolids application and this was attributed to the combined effects of a high EC and high concentrations of extractable P and NO
3
−. It was concluded that the increases in water storage and retention and microbial activity induced by additions of the composts is likely to improve the properties of bauxite-processing residue sand as a growth medium but that allowing time for soluble salts, originating from the organic amendments, to leach out may be an important consideration before sowing seeds.
Abstract The concept of fetal programming states that changes in the fetal environment during sensitive periods of organ development may cause long-lasting changes in the structure and functioning of ...these organs later in life and influence the risk for chronic diseases such as coronary heart disease and type 2 diabetes. Fetal growth is a summary marker of the fetal environment and is reflected by relatively easy-to-obtain measures of size at birth such as birth weight. In the last two decades, a body of evidence emerged linking fetal growth with behavioural and mental health outcomes later in life. Cognitive functioning and behavioural problems in childhood, in particular inattention/hyperactivity, have been shown to be inversely related to fetal growth. Although results are mixed, risk for personality disorders and schizophrenia seems to be linked with fetal growth and adversity, while the evidence for mood disorders is weak. Vulnerability for psychopathology may also be influenced by prenatal adversity. There is evidence for associations of fetal growth with temperament in childhood as well as stress reactivity and distress. The associations of fetal growth with mental health later in life are potentially caused by specific prenatal factors such as maternal smoking, alcohol, toxins/drugs, nutrition, psychosocial stress and infection during pregnancy. The mechanisms likely involve changes in neurodevelopment and in the set point of neuroendocrine systems, and there is evidence that prenatal adversity interacts with genetic and postnatal environmental factors. Future studies should examine the effects of specific prenatal factors and attempt to disentangle genetic and prenatal environmental effects.
Context.
The Extreme Ultraviolet Imager (EUI) is part of the remote sensing instrument package of the ESA/NASA Solar Orbiter mission that will explore the inner heliosphere and observe the Sun from ...vantage points close to the Sun and out of the ecliptic. Solar Orbiter will advance the “connection science” between solar activity and the heliosphere.
Aims.
With EUI we aim to improve our understanding of the structure and dynamics of the solar atmosphere, globally as well as at high resolution, and from high solar latitude perspectives.
Methods.
The EUI consists of three telescopes, the Full Sun Imager and two High Resolution Imagers, which are optimised to image in Lyman-
α
and EUV (17.4 nm, 30.4 nm) to provide a coverage from chromosphere up to corona. The EUI is designed to cope with the strong constraints imposed by the Solar Orbiter mission characteristics. Limited telemetry availability is compensated by state-of-the-art image compression, onboard image processing, and event selection. The imposed power limitations and potentially harsh radiation environment necessitate the use of novel CMOS sensors. As the unobstructed field of view of the telescopes needs to protrude through the spacecraft’s heat shield, the apertures have been kept as small as possible, without compromising optical performance. This led to a systematic effort to optimise the throughput of every optical element and the reduction of noise levels in the sensor.
Results.
In this paper we review the design of the two elements of the EUI instrument: the Optical Bench System and the Common Electronic Box. Particular attention is also given to the onboard software, the intended operations, the ground software, and the foreseen data products.
Conclusions.
The EUI will bring unique science opportunities thanks to its specific design, its viewpoint, and to the planned synergies with the other Solar Orbiter instruments. In particular, we highlight science opportunities brought by the out-of-ecliptic vantage point of the solar poles, the high-resolution imaging of the high chromosphere and corona, and the connection to the outer corona as observed by coronagraphs.
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