We perform numerical evolutions of the fully nonlinear Einstein (complex, massive) Klein-Gordon and Einstein (complex) Proca systems, to assess the formation and stability of spinning bosonic stars. ...In the scalar (vector) case these are known as boson (Proca) stars. Firstly, we consider the formation scenario. Starting with constraint-obeying initial data, describing a dilute, axisymmetric cloud of spinning scalar or Proca field, gravitational collapse toward a spinning star occurs, via gravitational cooling. In the scalar case the formation is transient, even for a nonperturbed initial cloud; a nonaxisymmetric instability always develops ejecting all the angular momentum from the scalar star. In the Proca case, by contrast, no instability is observed and the evolutions are compatible with the formation of a spinning Proca star. Secondly, we address the stability of an existing star, a stationary solution of the field equations. In the scalar case, a nonaxisymmetric perturbation develops, collapsing the star to a spinning black hole. No such instability is found in the Proca case, where the star survives large amplitude perturbations; moreover, some excited Proca stars decay to, and remain as, fundamental states. Our analysis suggests bosonic stars have different stability properties in the scalar (vector) case, which we tentatively relate to its toroidal (spheroidal) morphology. A parallelism with instabilities of spinning fluid stars is briefly discussed.
Phytoplankton cells are now recognized as dynamic entities rather than as passive and isolated particles because they can actively modulate impacts of selection factors (nutrients, light, turbidity, ...and mixing) through a wide range of adaptations. Cell shape and/or chain length modulation is one of these processes but has predominantly been studied as an adaptation or an acclimatation to a specific growth limitation (light, nutrients, predation, etc.). In this study we have demonstrated that cell shape and size may have greater roles than previously known in phytoplankton ecology and species adaptation by permitting cell‐to‐cell signaling and more complex ecological processes that result from it. By exploring microscale biophysical interactions that lead to specific cell reorientation processes, we demonstrated that cell geometry not only modulates cell sinking rates but can also provide fast sensor responses to the cells' environment. Although gyrotaxis has been described in detail for motile phytoplankton cells, our findings illustrate that the reorientation process described here can occur even in non‐motile cells within their natural environment. An additional consistent behavior was also recently described for a diatom species (Pseudo‐nitzschia delicatessima), and with this study, we extend this observation to Pseudo‐nitzschia pungens and Pseudo‐nitzschia fraudulenta. Our observations emphasize the generality of this process, which adds a new level of complexity to our understanding of cellular interactions and their network of sensors.
Systemic lupus erythematosus (SLE) is a complex disease with variable presentations, course and prognosis. We sought to develop evidence-based recommendations addressing the major issues in the ...management of SLE.
The EULAR Task Force on SLE comprised 19 specialists and a clinical epidemiologist. Key questions for the management of SLE were compiled using the Delphi technique. A systematic search of PubMed and Cochrane Library Reports was performed using McMaster/Hedges clinical queries' strategies for questions related to the diagnosis, prognosis, monitoring and treatment of SLE. For neuropsychiatric, pregnancy and antiphospholipid syndrome questions, the search was conducted using an array of relevant terms. Evidence was categorised based on sample size and type of design, and the categories of available evidence were identified for each recommendation. The strength of recommendation was assessed based on the category of available evidence, and agreement on the statements was measured across the 19 specialists.
Twelve questions were generated regarding the prognosis, diagnosis, monitoring and treatment of SLE, including neuropsychiatric SLE, pregnancy, the antiphospholipid syndrome and lupus nephritis. The evidence to support each proposition was evaluated and scored. After discussion and votes, the final recommendations were presented using brief statements. The average agreement among experts was 8.8 out of 10.
Recommendations for the management of SLE were developed using an evidence-based approach followed by expert consensus with high level of agreement among the experts.
To update the follow-up of the Euro-Lupus Nephritis Trial (ELNT), a randomised prospective trial comparing low-dose (LD) and high-dose (HD) intravenous (IV) cyclophosphamide (CY) followed by ...azathioprine (AZA) as treatment for proliferative lupus nephritis.
Data for survival and kidney function were prospectively collected during a 10-year period for the 90 patients randomised in the ELNT, except in 6 lost to follow-up.
Death, sustained doubling of serum creatinine and end-stage renal disease rates did not differ between the LD and HD group (5/44 (11%) vs 2/46 (4%), 6/44 (14%) vs 5/46 (11%) and 2/44 (5%) vs 4/46 (9%), respectively) nor did mean serum creatinine, 24 h proteinuria and damage score at last follow-up. Most patients in both groups were still treated with glucocorticoids, other immunosuppressant agents and blood pressure lowering drugs. After 10 years of follow-up, the positive predictive value for a good outcome of an early drop in proteinuria in response to initial immunosuppressive therapy was confirmed.
The data confirm that a LD IVCY regimen followed by AZA-the "Euro-Lupus regimen"-achieves good clinical results in the very long term.
Seventeen years (1998–2014) of satellite-derived chlorophyll concentration (Chl) are used to analyse the seasonal and non-seasonal patterns of Chl variability and the long-term trends in ...phytoplankton phenology in the Mediterranean Sea. With marked regional variations, we observe that seasonality dominates variability representing up to 80% of total Chl variance in oceanic areas, whereas in shelf-sea regions high frequency variations may be dominant representing up to 49% of total Chl variance. Seasonal variations are typically characterized by a phytoplankton growing period occurring in spring and spanning on average 170 days in the western basin and 150 days in the eastern basin. The variations in peak Chl concentrations are higher in the western basin (0.88 ± 1.01 mg m−3) compared to the eastern basin (0.35 ± 1.36 mg m−3). Differences in the seasonal cycle of Chl are also observed between open ocean and coastal waters where more than one phytoplankton growing period are frequent (>0.8 probability). During the study period, on average in the western Mediterranean basin (based on significant trends observed over ~95% of the basin), we show a positive trend in Chl of +0.015 ± 0.016 mg m−3 decade−1, and an increase in the amplitude and duration of the phytoplankton growing period by +0.27 ± 0.29 mg m−3 decade−1 and +11 ± 7 days decade−1 respectively. Changes in Chl concentration in the eastern (and more oligotrophic) basin are generally low, with a trend of −0.004 ± 0.024 mg m−3 decade−1 on average (based on observed significant trends over ~70% of the basin). In this basin, the Chl peak has declined by −0.03 ± 0.08 mg m−3 decade−1 and the growing period duration has decreased by −12 ± 7 days decade−1. The trends in phytoplankton Chl and phenology, estimated in this study over the period 1998–2014, do not reveal significant overall decline/increase in Chl concentration or earlier/delayed timings of the seasonal peak on average over the entire Mediterranean Sea basin. However, we observed large regional variations, suggesting that the response of phytoplankton to environmental and climate forcing may be complex and regionally driven.
•Trends in phytoplankton phenology in the Mediterranean Sea during 1998–2014•Basin and regional scale differences exist throughout the Mediterranean Sea.•Bloom duration and intensity increased in the western but reduced in the east basin.•Non-seasonal variability is locally important at straits and channels.•Regional processes are important in the modulation of phytoplankton phenology.
We have used Spitzer images of a sample of 68 barred spiral galaxies in the local universe to make systematic measurements of bar length and bar strength. We combine these with precise determinations ...of the corotation radii associated with the bars, taken from our previous study, which used the phase change from radial inflow to radial outflow of gas at corotation, based on high-resolution two-dimensional velocity fields in H taken with a Fabry-Pérot spectrometer. After presenting the histograms of the derived bar parameters, we study their dependence on the galaxy morphological type and on the total stellar mass of the host galaxy, and then produce a set of parametric plots. These include the bar pattern speed versus bar length, the pattern speed normalized with the characteristic pattern speed of the outer disk versus the bar strength, and the normalized pattern speed versus , the ratio of corotation radius to bar length. To provide guidelines for our interpretation, we used recently published simulations, including disk and dark matter halo components. Our most striking conclusion is that bars with values of < 1.4, previously considered dynamically fast rotators, can be among the slowest rotators both in absolute terms and when their pattern speeds are normalized. The simulations confirm that this is because as the bars are braked, they can grow longer more quickly than the outward drift of the corotation radius. We conclude that dark matter halos have indeed slowed down the rotation of bars on Gyr timescales.
► The CuO/γ-Al2O3 catalyst gave complete phenol conversion and 85% TOC reduction. ► High peroxide efficiency achieved with concentrations close to stoichiometric. ► Catalyst used in consecutive runs ...yields similar performance.
The use of hydrogen peroxide as the oxidizing agent in the presence of a catalyst (Catalytic Wet Peroxide Oxidation, CWPO) has emerged as a clean and effective alternative among other catalytic oxidation processes. The objective of this study is to evaluate the CWPO of phenol solutions using a high-load CuO/Al2O3 catalyst, which allows maintaining a high activity and efficiency compared to homogeneous copper, also overcoming secondary effluent contamination.
The catalytic oxidation of aqueous phenol solutions using H2O2 as oxidizing agent and a home-made CuO/Al2O3 catalyst was studied in a batchwise slurry reactor. The applied H2O2:phenol molar ratio was only nearly 30% higher than the stoichiometric ratio. Experiments were performed at temperatures between 303 and 343K using different catalyst loads. Phenol disappearance and TOC reduction were monitored throughout the reaction time.
Both phenol and TOC conversions were larger as temperature and catalyst load increased, following the higher hydrogen peroxide decomposition rates achieved. At the highest catalyst load and temperature, complete phenol conversion and ca. 80% TOC removal was achieved. Catalyst performance in terms of phenol and TOC disappearance was maintained after 12h of usage. Although there is evidence of some copper leaching from the catalyst, the homogeneous contribution to the overall activity is marginal.
The freshwater microalgae species Chlorella kessleri and Chlorella vulgaris, and the marine microalgae species Nannochloropsis oculata were cultivated in urban wastewater. The freshwater species ...demonstrated the possibility of growing in urban wastewater reaching high biomass production and nutrient removal when cultured in batch mode using a flat-panel airlift photobioreactor. Both microalgae species reached high biomass dry weights, 2.70±0.08g/L and 2.91±0.02g/L respectively, accompanied by nitrogen concentration reduction around 96% and 95%, and a phosphorous concentration reduction around 99% and 98% respectively. N. oculata was able to uptake nutrients from wastewater to grow but with less efficiency, indicating the need of microalgae acclimation or process optimisation to achieve high nutrient removals. During C. kessleri and C. vulgaris cultivation, the nitrogen consumption led to a progressive N-starvation process which increased the microalgae potential for biofuels production; both species produced 346±3mLCH4/gVS and 415±2mLCH4/gVS during anaerobic digestion, and 7.4±0.2gBiodiesel/100gVS and 11.3±0.1gBiodiesel/100gVS respectively.
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•The wastewater provides nutrients for freshwater and marine microalgae cultivation.•High microalgae growth is observed in the freshwater species when centrate is used.•C. kessleri and C. vulgaris remove >95% TN and >98% TP when grown in wastewater.•C. kessleri and C. vulgaris produce more CH4 than substrates commonly digested.•The N-starvation derived from nutrient removal is beneficial for biofuels production.
Microwave radiometry at low frequencies (L-band: 1.4 GHz, 21 cm) is an established technique for estimating surface soil moisture and sea surface salinity with a suitable sensitivity. However, from ...space, large antennas (several meters) are required to achieve an adequate spatial resolution at L-band. So as to reduce the problem of putting into orbit a large filled antenna, the possibility of using antenna synthesis methods has been investigated. Such a system, relying on a deployable structure, has now proved to be feasible and has led to the Soil Moisture and Ocean Salinity (SMOS) mission, which is described. The main objective of the SMOS mission is to deliver key variables of the land surfaces (soil moisture fields), and of ocean surfaces (sea surface salinity fields). The SMOS mission is based on a dual polarized L-band radiometer using aperture synthesis (two-dimensional 2D interferometer) so as to achieve a ground resolution of 50 km at the swath edges coupled with multiangular acquisitions. The radiometer will enable frequent and global coverage of the globe and deliver surface soil moisture fields over land and sea surface salinity over the oceans. The SMOS mission was proposed to the European Space Agency (ESA) in the framework of the Earth Explorer Opportunity Missions. It was selected for a tentative launch in 2005. The goal of this paper is to present the main aspects of the baseline mission and describe how soil moisture will be retrieved from SMOS data.
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