Bioaugmentation of UASB reactors with immobilized Sulfurospirillum barnesii for simultaneous selenate and nitrate removal

Whole-cell immobilization of selenate-respiring Sulfurospirillum barnesii in polyacrylamide gels was investigated to allow the treatment of selenate contaminated (790¿µg Se¿×¿L-1) synthetic wastewater with a high molar excess of nitrate (1,500 times) and sulfate (200 times). Gel-immobilized S. barnesii cells were used to inoculate a mesophilic (30°C) bioreactor fed with lactate as electron donor at an organic loading rate of 5 g chemical oxygen demand (COD)¿×¿L-1 day-1. Selenate was reduced efficiently (>97%) in the nitrate and sulfate fed bioreactor, and a minimal effluent concentration of 39¿µg Se¿×¿L-1 was obtained. Scanning electron microscopy with energy dispersive X-ray (SEM–EDX) analysis revealed spherical bioprecipitates of =2¿µm diameter mostly on the gel surface, consisting of selenium with a minor contribution of sulfur. To validate the bioaugmentation success under microbial competition, gel cubes with immobilized S. barnesii cells were added to an Upflow Anaerobic Sludge Bed (UASB) reactor, resulting in earlier selenate (24 hydraulic retention times (HRTs)) and sulfate (44 HRTs) removal and higher nitrate/nitrite removal efficiencies compared to a non-bioaugmented control reactor. S. barnesii was efficiently immobilized inside the UASB bioreactors as the selenate-reducing activity was maintained during long-term operation (58 days), and molecular analysis showed that S. barnesii was present in both the sludge bed and the effluent. This demonstrates that gel immobilization of specialized bacterial strains can supersede wash-out and out-competition of newly introduced strains in continuous bioaugmented systems. Eventually, proliferation of a selenium-respiring specialist occurred in the non-bioaugmented control reactor, resulting in simultaneous nitrate and selenate removal during a later phase of operatio

A stochastic movement simulator improves estimates of landscape connectivity

Acknowledgments This publication issued from the project TenLamas funded by the French Ministère de l'Energie, de l'Ecologie, du Développement Durable et de la Mer through the EU FP6 BiodivERsA Eranet; by the Agence Nationale de la Recherche (ANR) through the open call INDHET and 6th extinction MOBIGEN to V. M. Stevens, M. Baguette, and A. Coulon, and young researcher GEMS (ANR-13-JSV7-0010-01) to V. M. Stevens and M. Baguette; and by a VLIR-VLADOC scholarship awarded to J. Aben. L. Lens, J. Aben, D. Strubbe, and E. Matthysen are grateful to the Research Foundation Flanders (FWO) for financial support of fieldwork and genetic analysis (grant G.0308.13). V. M. Stevens and M. Baguette are members of the “Laboratoire d'Excellence” (LABEX) entitled TULIP (ANR-10-LABX-41). J. M. J. Travis and S. C. F. Palmer also acknowledge the support of NERC. A. Coulon and J. Aben contributed equally to the work.Peer reviewedPublisher PD

Sensitivities of Low Energy Reactor Neutrino Experiments

The low energy part of the reactor neutrino spectra has not been experimentally measured. Its uncertainties limit the sensitivities in certain reactor neutrino experiments. The origin of these uncertainties are discussed, and the effects on measurements of neutrino interactions with electrons and nuclei are studied. Comparisons are made with existing results. In particular, the discrepancies between previous measurements with Standard Model expectations can be explained by an under-estimation of the low energy reactor neutrino spectra. To optimize the experimental sensitivities, measurements for \nuebar-e cross-sections should focus on events with large ($>$1.5 MeV) recoil energy while those for neutrino magnetic moment searches should be based on events $<$100 keV. The merits and attainable accuracies for neutrino-electron scattering experiments using artificial neutrino sources are discussed.Comment: 25 pages, 9 figure

Late presentation of chronic HBV and HCV patients seeking first time specialist care in Spain: a 2-year registry review

Chronic viral hepatitis infection affects an estimated 325 million people globally. People who initiate treatment after significant disease progression face increased risk of severe liver complications and death. Data are scarce on the characteristics and risk factors of people who present late to care in Spain and globally. Data were collected from January 2018 to December 2019 to report late presentation (LP) to specialist care at 11 large university hospitals in Spain to assess related risk factors using a multivariable logistic regression model. 2290 (CHB = 505, CHC = 1785) patients were analysed, with 581 (25.2%) presenting late. Hepatitis C patients more frequently reported LP compared to hepatitis B patients (28.1% vs 15.0%; p < 0.001). Older age (p < 0.001), being male (p < 0.001), being Spanish‑born (p < 0.001), and having an unknown origin of referral (p = 0.08) were associated with a higher likelihood of LP. Advanced liver disease was identified in 533 (23%) patients and late‑stage liver disease in 124 (5.4%). LP, including with irreversible liver damage, to viral hepatitis specialist care is frequent in Spain, despite being a country with unrestricted treatment access. Initiatives to reduce LP should specifically target men, older individuals, foreign‑born populations for CHB, and Spanish nationals for CHC

Primary aortic thrombosis: role of enhanced multislice CT demonstrated in three exceptional cases.

Primary aortic thrombosis remains a rare entity that can be defined as clotting of the vessel without any obvious atheromatous lesion. Cancer chemotherapy, cocaine intake, essential thrombocythemia, some hypercoagulable states, heparin-induced thrombocytopenia, inflammatory disease of the digestive tract and acute pancreatitis are, beside some cases of rather unknown etiology, the causes of primary aortic thrombosis. Intravenous contrast-enhanced multislice CT, which is widely available, noninvasive and affordable in terms of cost, is the imaging modality of choice for the investigation of primary aortic thrombosis and the assessment of potential complications. Three cases due to chemotherapy, antiphospholipid syndrome and acute pancreatitis are reported

Interspecific Introgression in Cetaceans: DNA Markers Reveal Post-F1 Status of a Pilot Whale

Visual species identification of cetacean strandings is difficult, especially when dead specimens are degraded and/or species are morphologically similar. The two recognised pilot whale species (Globicephala melas and Globicephala macrorhynchus) are sympatric in the North Atlantic Ocean. These species are very similar in external appearance and their morphometric characteristics partially overlap; thus visual identification is not always reliable. Genetic species identification ensures correct identification of specimens. Here we have employed one mitochondrial (D-Loop region) and eight nuclear loci (microsatellites) as genetic markers to identify six stranded pilot whales found in Galicia (Northwest Spain), one of them of ambiguous phenotype. DNA analyses yielded positive amplification of all loci and enabled species identification. Nuclear microsatellite DNA genotypes revealed mixed ancestry for one individual, identified as a post-F1 interspecific hybrid employing two different Bayesian methods. From the mitochondrial sequence the maternal species was Globicephala melas. This is the first hybrid documented between Globicephala melas and G. macrorhynchus, and the first post-F1 hybrid genetically identified between cetaceans, revealing interspecific genetic introgression in marine mammals. We propose to add nuclear loci to genetic databases for cetacean species identification in order to detect hybrid individuals.