The work presented here focuses on the analysis of a turbulent boundary layer saturated with saltating particles. Experiments were carried out in a wind tunnel 15m long and 0.6m wide at the ...University of Aarhus in Denmark with sand grains 242 μm in size for wind speeds ranging from the threshold speed to twice its value. The saltating particles were analysed using particle image velocimetry (PIV) and particle-tracking velocimetry (PTV), and vertical profiles of particle concentration and velocity were extracted. The particle concentration was found to decrease exponentially with the height above the bed, and the characteristic decay height was independent of the wind speed. In contrast with the logarithmic profile of the wind speed, the grain velocity was found to vary linearly with the height. In addition, the measurements indicated that the grain velocity profile depended only slightly on the wind speed. These results are shown to be closely related to the features of the splash function that characterizes the impact of the saltating particles on a sandbed. A numerical simulation is developed that explicitly incorporates low-velocity moments of the splash function in a calculation of the boundary conditions that apply at the bed. The overall features of the experimental measurements are reproduced by simulation.
We describe a partial filament eruption on 11 December 2011 that demonstrates that the inclusion of mass is an important next step for understanding solar eruptions. Observations from the
Solar ...Terrestrial Relations Observatory-Behind
(STEREO-B) and the
Solar Dynamics Observatory
(SDO) spacecraft were used to remove line-of-sight projection effects in filament motion and correlate the effect of plasma dynamics with the evolution of the filament height. Flux cancellation and nearby flux emergence are shown to have played a role in increasing the height of the filament
prior
to eruption. The two viewpoints allow the quantitative estimation of a large mass-unloading, the subsequent radial expansion, and the eruption of the filament to be investigated. A 1.8 to 4.1 lower-limit ratio between gravitational and magnetic-tension forces was found. We therefore conclude that following the loss-of-equilibrium of the flux-rope, the radial expansion of the flux-rope was restrained by the filamentary material until 70% of the mass had evacuated the structure through mass-unloading.
Potable water in developing countries often contains levels of toxic metals that exceed the recommended international limits, with impacts on human health. The aim of the present study was to develop ...a low cost aerogel synthesised from graphene oxide (GO) cross-linked with alginate to remove Pb2+ from potable water. Aerogels were made by a sol-gel of the composite materials followed by a freeze drying method. The shape of the aerogels were 50 mm diameter disks, 5 mm deep and characterised by an open porous network of 50 to 150 micrometres which are mechanically robust upon hydration. Firstly, the study was conducted using a batch adsorption method from a starting concentration 0.48 mM (100 mg/l) of Pb2+ in ultrapure water over 240 min, n = 4 with controls. A second series of experiments compared the adsorption of different competing ions at different valencies (Na+, Ca2+, Cu2+, La3+) in an equivalent media. A third series of experiments explored Pb2+ desorption from the aerogel at low pH and in highly acidic conditions. This simple filter system, based on a batch adsorption methodology expresses a high affinity for Pb2+ resulting in an ultra-high mean maximum adsorption capacity of 504 mg/g of Pb2+ within 240 mins at pH 5. The aerogel can also adsorb other toxic metal salts such as La3+ and Cu2+ with a capacity of 146 and 193 mg/g respectively. Furthermore, the aerogel structure can be acid washed removing 98% of the Pb2+ from the structure within three minutes. Overall, the data shows that GO alginate aerogels are highly effective at removing Pb2+ from water and the primary mechanism involved is ion exchange, although other phenomenon such as proton tunnelling may be a contributing factor to the ultra-high efficiency of the aerogel for Pb2+ remediation.
•Graphene oxide aerogels with nano-enhanced novel sorption mechanism for lead.•Graphene oxide and alginate aerogels, mechanically robust and pH resistant.•Aerogels with ultrahigh lead adsorption capacity, greater than 500 mg/g.•Toxic metal removal possibly due to the quantum effect of proton tunnelling.•98% of lead adsorbed can be reclaimed within 3 min.
GABAergic circuits are critical for the synchronization and higher order function of brain networks. Defects in this circuitry are linked to neuropsychiatric diseases, including bipolar disorder, ...schizophrenia, and autism. Work in cultured neurons has shown that ankyrin-G plays a key role in the regulation of GABAergic synapses on the axon initial segment and somatodendritic domain of pyramidal neurons, where it interacts directly with the GABA
receptor-associated protein (GABARAP) to stabilize cell surface GABA
receptors. Here, we generated a knock-in mouse model expressing a mutation that abolishes the ankyrin-G/GABARAP interaction (Ank3 W1989R) to understand how ankyrin-G and GABARAP regulate GABAergic circuitry in vivo. We found that Ank3 W1989R mice exhibit a striking reduction in forebrain GABAergic synapses resulting in pyramidal cell hyperexcitability and disruptions in network synchronization. In addition, we identified changes in pyramidal cell dendritic spines and axon initial segments consistent with compensation for hyperexcitability. Finally, we identified the ANK3 W1989R variant in a family with bipolar disorder, suggesting a potential role of this variant in disease. Our results highlight the importance of ankyrin-G in regulating forebrain circuitry and provide novel insights into how ANK3 loss-of-function variants may contribute to human disease.
•Biological amendments include biostimulants, organic amendments and inoculants.•Some biological amendments may have potential cumulative effects.•Modes of action of biological amendments in the ...field are not always understood.•Scientific evidence of field-scale benefits of biological amendments is limited.•On-farm participatory research has potential to provide valuable knowledge.
There is increasing interest in use of ‘alternative’ soil amendments in agriculture, but the wide range of resources and products available differ greatly in their potential to overcome soil constraints and improve nutrient use efficiency. The three main types of biological amendments can be categorised as biostimulants, organic amendments and microbial inoculants. Many have potential to influence biological, chemical and physical conditions of soil, but most are not well researched or easily used in agriculture. The main exception is legume inoculants, which are very well researched and contribute enormously to agricultural productivity when legumes are incorporated into farming systems. Biostimulants include amino acids, chitosan, seaweed extracts and humic substances. Organic amendments include manures, composts, compost derivatives and biochars. Microbial inoculants include specific bacterial inoculants for legumes, and less specialised rhizosphere bacteria, arbuscular mycorrhizal fungi, ectomycorrhizal fungi and a range of disease suppressing microorganisms. Some biological amendments applied to soil may be more effective when used in combinations rather than singly. Furthermore, those used over longer periods may have potential for cumulative effects not captured when used over shorter timeframes. Such differences in effectiveness would occur primarily where benefits involve microbial interactions with chemical and physical soil processes leading to slow transformations within the soil matrix that influence soil fertility and soil health. Similarly, addition of manures and composts may require several years for any quantifiable increase in soil organic C. Although considerable knowledge of the modes of action of many biological amendments is available, their performance under field conditions is usually less well understood. The wide variety of natural and manufactured products available in most cases precludes adequate peer-reviewed research to support claims about their effectiveness. This can lead to proliferation of unsubstantiated assertions of efficacy. This review highlights the lack of field-scale evidence of benefits for many biological amendments with potential to be used in agriculture. We propose complementary approaches of (i) laboratory- or glasshouse-scale research to understand modes of action, and (ii) targeted field-scale participatory research involving groups of farmers using on-farm trials as a forward pathway. Use of biological amendments to overcome soil constraints is expected to expand with intensification of agriculture and as a result of climate change. Therefore, information that enables farmers to discriminate among products that have different levels of effectiveness is necessary, and on-farm participatory research should contribute to addressing this need.
Abstract
We present the first analysis of Cepheid stars observed by the TESS space mission in Sectors 1–5. Our sample consists of 25 pulsators: ten fundamental mode, three overtone and two ...double-mode classical Cepheids, plus three type II and seven anomalous Cepheids. The targets were chosen from fields with different stellar densities, both from the Galactic field and from the Magellanic System. Three targets have 2 minutes cadence light curves available by the TESS Science Processing Operations Center: for the rest, we prepared custom light curves from the full-frame images with our own differential photometric FITSH pipeline. Our main goal was to explore the potential and the limitations of TESS concerning the various subtypes of Cepheids. We detected many low-amplitude features: weak modulation, period jitter, and timing variations due to light-time effect. We also report signs of nonradial modes and the first discovery of such a mode in an anomalous Cepheid, the overtone star XZ Cet, which we then confirmed with ground-based multicolor photometric measurements. We prepared a custom photometric solution to minimize saturation effects in the bright fundamental-mode classical Cepheid,
β
Dor with the
lightkurve
software, and we revealed strong evidence of cycle-to-cycle variations in the star. In several cases, however, fluctuations in the pulsation could not be distinguished from instrumental effects, such as contamination from nearby sources, which also varies between sectors. Finally, we discuss how precise light-curve shapes will be crucial not only for classification purposes but also to determine physical properties of these stars.
Summary
Background
In asthma, the airway inflammatory phenotype influences clinical characteristics and treatment response. Although induced sputum is the gold standard test for phenotyping asthma, a ...more accessible method is needed for clinical practice.
Objective
To investigate whether white blood cell counts and/or their derived ratios can predict sputum eosinophils or neutrophils in uncontrolled asthma.
Methods
This cross‐sectional study evaluated 164 treated but uncontrolled asthmatic patients with sputum induction and blood collection. Receiver‐operating characteristic (ROC) curves were used to assess the relationship between blood and sputum parameters.
Results
There was a significant positive relationship between blood eosinophil parameters and the percentage of sputum eosinophil count. A weak but significant correlation was found between sputum neutrophil percentage and blood neutrophil percentage (r = 0.219, P = 0.005). ROC curve analysis identified that blood eosinophil percentage count was the best predictor for eosinophilic asthma, with an area under the curve (AUC) of 0.907 (P < 0.001). The optimum cut‐point for blood eosinophil percentage was 2.7%, and this yielded a sensitivity of 92.2% and a specificity of 75.8%. The absolute blood eosinophil count was also highly predictive with an AUC of 0.898 (P < 0.0001) at a blood eosinophil cut‐off of 0.26 × 109/L. The blood eosinophil/lymphocyte ratio (ELR) and eosinophil/neutrophil ratio (ENR) were increased in eosinophilic asthma, and the neutrophil/lymphocyte ratio (NLR) was increased in neutrophilic asthma. Neutrophilic asthma could also be detected by blood neutrophil percentages and NLR, but with less accuracy.
Conclusions and Clinical Relevance
Blood eosinophil counts and derived ratios (ELR and ENR) can accurately predict eosinophilic asthma in patients with persistent uncontrolled asthma despite treatment. Blood neutrophil parameters are poor surrogates for the proportion of sputum neutrophils. Blood counts may be a useful aid in the monitoring of uncontrolled asthma.
AU Microscopii (AU Mic) is the second closest pre-main-sequence star, at a distance of 9.79 parsecs and with an age of 22 million years
. AU Mic possesses a relatively rare
and spatially resolved
...edge-on debris disk extending from about 35 to 210 astronomical units from the star
, and with clumps exhibiting non-Keplerian motion
. Detection of newly formed planets around such a star is challenged by the presence of spots, plage, flares and other manifestations of magnetic 'activity' on the star
. Here we report observations of a planet transiting AU Mic. The transiting planet, AU Mic b, has an orbital period of 8.46 days, an orbital distance of 0.07 astronomical units, a radius of 0.4 Jupiter radii, and a mass of less than 0.18 Jupiter masses at 3σ confidence. Our observations of a planet co-existing with a debris disk offer the opportunity to test the predictions of current models of planet formation and evolution.
Summary
Numerous health consequences of tobacco smoke exposure have been characterized, and the effects of smoking on traditional measures of male fertility are well described. However, a growing ...body of data indicates that pre‐conception paternal smoking also confers increased risk for a number of morbidities on offspring. The mechanism for this increased risk has not been elucidated, but it is likely mediated, at least in part, through epigenetic modifications transmitted through spermatozoa. In this study, we investigated the impact of cigarette smoke exposure on sperm DNA methylation patterns in 78 men who smoke and 78 never‐smokers using the Infinium Human Methylation 450 beadchip. We investigated two models of DNA methylation alterations: (i) consistently altered methylation at specific CpGs or within specific genomic regions and (ii) stochastic DNA methylation alterations manifest as increased variability in genome‐wide methylation patterns in men who smoke. We identified 141 significantly differentially methylated CpGs associated with smoking. In addition, we identified a trend toward increased variance in methylation patterns genome‐wide in sperm DNA from men who smoke compared with never‐smokers. These findings of widespread DNA methylation alterations are consistent with the broad range of offspring heath disparities associated with pre‐conception paternal smoke exposure and warrant further investigation to identify the specific mechanism by which sperm DNA methylation perturbation confers risk to offspring health and whether these changes can be transmitted to offspring and transgenerationally.
ABSTRACT
Based on HARPS-N radial velocities (RVs) and TESS photometry, we present a full characterization of the planetary system orbiting the late G dwarf TOI-561. After the identification of three ...transiting candidates by TESS, we discovered two additional external planets from RV analysis. RVs cannot confirm the outer TESS transiting candidate, which would also make the system dynamically unstable. We demonstrate that the two transits initially associated with this candidate are instead due to single transits of the two planets discovered using RVs. The four planets orbiting TOI-561 include an ultra-short period (USP) super-Earth (TOI-561 b) with period Pb = 0.45 d, mass Mb = 1.59 ± 0.36 M⊕ and radius Rb = 1.42 ± 0.07 R⊕, and three mini-Neptunes: TOI-561 c, with Pc = 10.78 d, Mc = 5.40 ± 0.98 M⊕, Rc = 2.88 ± 0.09 R⊕; TOI-561 d, with Pd = 25.6 d, Md = 11.9 ± 1.3 M⊕, Rd = 2.53 ± 0.13 R⊕; and TOI-561 e, with Pe = 77.2 d, Me = 16.0 ± 2.3 M⊕, Re = 2.67 ± 0.11 R⊕. Having a density of 3.0 ± 0.8 g cm−3, TOI-561 b is the lowest density USP planet known to date. Our N-body simulations confirm the stability of the system and predict a strong, anti-correlated, long-term transit time variation signal between planets d and e. The unusual density of the inner super-Earth and the dynamical interactions between the outer planets make TOI-561 an interesting follow-up target.
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