Increasing the volume of untreated and inadequately treated municipal wastewater undermines the circular economy potential of wastewater resources, particularly in low-income regions. This present ...study focused on and evaluated the performance of native microalgae-activated sludge (MAS) growth for tertiary treatment of anaerobically digested wastewater from an up-flow anaerobic sludge blanket (UASB) in an outdoor lab-scale photobioreactor (2.2 L). Three conditions with distinct MAS inoculum concentrations alongside three controls were operated in batch mode for 5 days hydraulic retention time (HRT) at 11.5:12.5 photo-hours. The MAS inoculum concentration influenced the treatment outcome. The best performance was observed when the MAS concentration was 0.10/0.20 g L−1, and the cell density was 1.60 × 107 cells mL−1, total biomass productivity of 0.10 g TSS L−1 d−1, total phosphorus uptake of 85.1%, and total nitrogen uptake of 66.1%. Logarithmic removal (Log-Re) of bacterial pathogens (water quality indicators) showed Log-Re 3.4 for total coliforms (1.37 × 102 CFU 100 mL−1) and 4.7 for Escherichia coli (0.00 × 100 CFU 100 mL−1). The results revealed optimum remediation performance and nutrient recovery potential with appropriate inoculum concentration, in admiration to advancing the science of circular economy.
Context. The bright southern Cepheid RS Pup is surrounded by a circumstellar nebula reflecting the light from the central star. The propagation of the light variations from the Cepheid inside the ...dusty nebula creates spectacular light echoes that can be observed up to large distances from the star itself. This phenomenon is currently unique in this class of stars. Aims. For this relatively distant star, the trigonometric parallax available from Hipparcos has a low accuracy. A careful observation of the light echoes has the potential to provide a very accurate, geometric distance to RS Pup. Methods. We obtained a series of CCD images of RS Pup with the NTT/EMMI instrument covering the variation period of the star (P = 41.4 d), allowing us to track the progression of the light wavefronts over the nebular features surrounding the star. We measured precisely the phase lag of the photometric variation in several regions of the circumstellar nebula. Results. From our phase lag measurements, we derive a geometric distance of 1992 pm 28 pc to RS Pup. This distance is affected by a total uncertainty of 1.4%, and corresponds to a parallax of pi = 0.502 pm 0.007 mas and a distance modulus of mu = 11.50 pm 0.03. Conclusions. The geometric distance we derive is by far the most accurate to a Cepheid, and among the most accurate to any star. RS Pup appears both as somewhat neglected and particularly promising to investigate the mass-loss history of Cepheids. Thanks to its highly accurate distance, it is also bound to become an important luminosity fiducial for the long period part of the period- luminosity diagram.
► Critical loads of acidity and eutrophication determined for UNECE ICP IM sites. ► European Integrated Monitoring sites still affected by acidification in 2020. ► Half of sites studied susceptible ...to eutrophication in 2020. ► Exceedance of CL acidity correlated with key acidification indicators in runoff. ► Evidence of link between exceedance of CL nitrogen and nitrogen leached.
Critical loads for acidification and eutrophication and their exceedances were determined for a selection of ecosystem effects monitoring sites in the Integrated Monitoring programme (UNECE ICP IM). The level of protection of these sites with respect to acidifying and eutrophying deposition was estimated for 2000 and 2020. In 2020 more sites were protected from acidification (67%) than in 2000 (61%). However, due to the sensitivity of the sites, even the maximum technically feasible emission reductions scenario would not protect all sites from acidification. In 2000, around 20% of the IM sites were protected from eutrophication. In 2020, under reductions in accordance with current legislation, about one third of the sites would be protected, and at best, with the maximum technically feasible reductions, half of the sites would be protected from eutrophication. Data from intensively monitored sites, such as those in ICP IM, provide a connection between modelled critical thresholds and empirical observations, and thus an indication of the applicability of critical load estimates for natural ecosystems. Across the sites, there was good correlation between the exceedance of critical loads for acidification and key acidification parameters in runoff water, both with annual mean fluxes and concentrations. There was also evidence of a link between exceedances of critical loads of nutrient nitrogen and nitrogen leaching. The collected empirical data of the ICP IM thus allow testing and validation of key concepts used in the critical load calculations. This increases confidence in the European-scale critical loads mapping used in integrated assessment modelling to support emission reduction agreements.
Context. Multi-wavelength observations of Hicksons Compact Groups (HCGs) have shown that many of these groups are physical bound structures and are in different stage of evolution, from ...spiral-dominated systems to almost merged objects. Very few studies have analysed the Southern Compact Groups (SCGs) sample, which is thought to be younger that HCGs, due to an on average higher number of spiral galaxies. We present here the first results from optical and radio observations on a pilot sample of SCGs. Aims. Previous HI studies of HCGs seems to corroborate an evolutionary sequence from low velocity dispersion, spiral dominated, young and star-forming groups to higher velocity dispersion, mostly early-type, X-ray bright groups. In this scheme, the dominant parameter is most likely the ratio between the galaxy mass vs. the available gas mass. A second parameter, namely the merging history of the group, however might have an important role in the evolution of the intra-group medium. Powerful merging events and/or interactions can contribute significantly to the heating of the intra-group medium by means of supernova explosions or by triggering an AGN. We propose to investigate whether the evolutionary scheme of the intragroup medium found for HCGs also holds in a different compact group sample. In addition to this, we start in this paper to investigate which is the influence of the merging history of groups on their evolution. Methods. Optical observations of SCGs obtained with ESO telescopes and radio data from the ATCA allow us to probe the distribution of the warm intra-group medium and the evolutionary stage of each group, by means of morphological studies and via measurements of star formation and other types of nuclear activity. Results. We present here results from a pilot sample of SCGs: we find an evolutionary trend, based on the properties of the warm intra-group medium, similar to what has been found for HCGs. Both galaxies with Sy2 nuclei in our sample are members of groups in the late stages of their dynamical evolution. However while one group is strongly HI deficient and shows, at the same time a strong ongoing merging, the other does not show any HI deficiency and the galaxies are only interacting with each other.
The frequency of skin tumors of all types and specifically of squamous cell carcinoma (SCC) is increased in heart transplantation (HT), but the predisposing risk factors are controversial.
We studied ...300 patients (age 49+/-15 years, 258 men, mean follow-up 4.6 years, follow-up range 1 month to 12 years) who were receiving standard double (cyclosporin plus azathioprine) or triple (cyclosporin plus azathioprine plus prednisone) therapy. The first-year rejection score was calculated for endomyocardial biopsy samples (International Society for Heart and Lung Transplantation grade 0=0, 1A=1, 1B=2, 2=3, 3A=4, 3B=5, and 4=6) and used as an indirect marker of the level of immunosuppression. Multivariate analysis (Cox regression) included age at HT, sex, skin type, first-year rejection score, presence of warts and solar keratosis, lifetime sunlight exposure, and first-year cumulative dose of steroids. The incidence of skin tumors of all types increased from 15% after 5 years to 35% after 10 years after HT according to life-table analysis. Age at HT of >50 years (P:=0.03, RR=5.3), skin type II (P:=0.05, RR=2.6), rejection score of 19 (P:=0.003, RR=5.7), solar keratosis (P:=0.001, RR=6.9), and lifetime sunlight exposure of >30 000 hours (P:=0.0003, RR=7.6) were risk factors for SCC.
Older age at HT, light skin type, solar keratosis, greater sunlight exposure, and high rejection score in the first year were independently associated with an increased risk of SCC. The progressive increase in cancer frequency during follow-up and the association with high rejection scores suggest that both the length and level of immunosuppression may be relevant. Because cumulative immunosuppressive load is cumbersome to calculate, a high rejection score in the first year may provide a useful predictor for patients at risk.
Removal of pharmaceuticals and personal care products (PPCPs) from drinking water is usually enhanced by advanced oxidation which is not affordable in low income countries. Slow sand filtration has ...been found to be capable of removing anti-inflammatory compounds, and its low maintenance costs and easy operation make it an attractive technology for treating drinking water in many parts of the world. In addition, slow sand filters can be used at both large and household scales. The biofilm (i.e. schmutzdecke) developed on the top of the sand and within the upper layers of the sand is acknowledged to be responsible for the water purification. However, it is possible that the PPCPs may affect the schmutzdecke development and microbial community within the filters, and consequently the performance of the filter. This study investigated two household slow sand filters (for water purification) operated intermittently with and without contamination by six PPCPs. Eleven parameters were monitored in the affluent and effluent water, including bacterial species present and schmutzdecke biomass development. Results demonstrated that the household slow sand filter performance was not affected by the 2μgL−1 of PPCPs in the water. There was no significant difference between filters for total coliforms and E. coli removal, but there was considerable difference between sampling times. Biomass considerably increased with the number of filtrations in both filters and there was no significant difference between filter biomass. However, it was found that more bacterial species were present in the period with no contamination than during the contamination period. Bacillus anthracis and Exiguobacterium sp. showed to be resistant to the effects of the PPCPs. These suggest there are effects of PPCPs on bacterial species within the filter. However, the effect of the PPCPs on biomass was not conclusive in this study and needs to be further investigated.
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•Intermittently operated slow sand filter for household water purification•Filters' performance were not affected by PPCPs in affluent water.•Raw water was contaminated with benzophenone-3 and paracetamol.•Diclofenac, naproxen, ibuprofen and methylparaben were completely removed by slow sand filter.•Bacillus anthracis and Exiguobacterium sp. were found resistant to 2μgL−1 of PPCPs.
Aims. Compact groups of galaxies are excellent laboratories for studying galaxy interactions and their effects on the evolution of galaxies. In particular, dynamically young systems, with a large ...fraction of interacting, late type galaxies, have so far escaped proper studies in the X-ray band and their hot intergalactic medium properties are virtually unknown. Motivated by this lack of knowledge, we present a detailed investigation here of the X-ray properties of such a dynamically young system. Methods. We obtained XMM-Newton observations of one spiral-only system in the new southern compact group catalogue: SCG0018-4854. We present here the results of the data analysis and discuss them in comparison with the few other similar systems also studied in the X-ray band. Results. The 4 members of SCG0018-4854 emit at a level comparable to what is expected based on their optical properties. We detect the low level diffuse emission between galaxies, which is most likely due to the presence of the intergalactic medium. Compared to other spiral–only groups, SCG0018-4854 could be the coolest system detected so far, although the measurements have large uncertainties. These results indicate that high quality deep X-ray observations are needed to allow a proper study of the properties of the potential well of dynamically young systems, before more general conclusions can be drawn on their average characteristics.
We present charge-coupled device UBVI photometry and high-resolution spectroscopy of the intermediate-age open cluster NGC 3960. The colour-magnitude diagrams (CMDs) derived from the photometric data ...and interpreted with the synthetic CMD method allow us to estimate the cluster parameters. We derive the following: age τ = 0.9 or 0.6 Gyr (depending on whether or not overshooting from convective regions is included in the adopted stellar models); distance (m-M)0 = 11.6 ± 0.1; reddening E(B-V) = 0.29 ± 0.02; differential reddening ΔE(B-V) = 0.05; and approximate metallicity between solar and half-solar. We obtained high-resolution spectra of three clump stars, and derived an average Fe/H=−0.12 (rms 0.04 dex), in very good agreement with the photometric determination. We also obtained the abundances of α-elements, of Fe-peak elements and of Ba. The reddenings towards individual stars derived from the spectroscopic temperatures and the calibrations of Alonso et al. give further support to the existence of significant variations across the cluster.
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