728 research outputs found

    Kinetic modeling and microbial assessment by fluorescent in situ hybridization in anaerobic sequencing batch biofilm reactors treating sulfate-rich wastewater

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    This paper reports the results of applying anaerobic sequencing batch biofilm reactors (AnSBBR) for treating sulfate-rich wastewater. The reactor was filled with polyurethane foam matrices or with eucalyptus charcoal, used as the support for biomass attachment. Synthetic wastewater was prepared with two ratios between chemical oxygen demand (COD) and sulfate concentration (COD/SO4(2-)) of 0.4 and 3.2. For a COD/SO4(2-) ratio of 3.2, the AnSBBR performance was influenced by the support material used; the average levels of organic matter removal were 67% and 81% in the reactors filled with polyurethane foam and charcoal, respectively, and both support materials were associated with similar levels of sulfate reduction (above 90%). In both reactors, sulfate-reducing bacteria (SRB) represented more than 65% of the bacterial community. The kinetic model indicated equilibrium between complete- and incomplete-oxidizing SRB in the reactor filled with polyurethane foam and predominantly incomplete-oxidizing SRB in the reactor filled with charcoal. Methanogenic activity seems to have been the determining factor to explain the better performance of the reactor filled with charcoal to remove organic matter at a COD/SO4(2-) ratio of 3.2. For a COD/SO4(2-) ratio of 0.4, low values of sulfate reduction (around 32%) and low reaction rates were observed as a result of the small SRB population (about 20% of the bacterial community). Although the support material did not affect overall performance for this condition, different degradation pathways were observed; incomplete oxidation of organic matter by SRB was the main kinetic pathway and methanogenesis was negligible in both reactors.This work was funded by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and the Financiadora de Estudos e Projetos (FINEP), Brazil. The authors acknowledge the grants received from FAPESP and the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Brazi

    Search for neutrino oscillations on a long base-line at the CHOOZ nuclear power station

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    This final article about the CHOOZ experiment presents a complete description of the electron antineutrino source and detector, the calibration methods and stability checks, the event reconstruction procedures and the Monte Carlo simulation. The data analysis, systematic effects and the methods used to reach our conclusions are fully discussed. Some new remarks are presented on the deduction of the confidence limits and on the correct treatment of systematic errors.Comment: 41 pages, 59 figures, Latex file, accepted for publication by Eur.Phys.J.

    High-resolution in situ holographic recording and analysis of marine organisms and particles (HOLOMAR)

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    We report on the development of a fully- unctioning, prototype, underwater holographic camera (holo-camera) for holographic recording of large-volumes of sea water containing marine plankton and seston within the upper water column The overriding benefit of holographic imaging over other measurement techniques is that it allows non-intrusive and non-destructive, in-situ, recording of living organisms and inanimate particles in their natural environment. Because of the inherently high resolution of holography, its threedimensional imaging properties and the ability to perform "optical sectioning" on the image, it allows identification of particular organisms together with the extraction of sue and relative positional information This information, in turn, affords the ability to gain knowledge of the behaviour of marine biological communities, their relationship with each other and with the particles with which they interact

    Bilirubin decreases NOS2 expression via inhibition of NAD(P)H oxidase: implications for protection against endotoxic shock in rats.

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    We investigated a possible beneficial role for bilirubin, one of the products of heme degradation by the cytoprotective enzyme heme oxygenase-1 in counteracting Escherichia coli endotoxin-mediated toxicity. Homozygous jaundice Gunn rats, which display high plasma bilirubin levels due to deficiency of glucuronyl transferase activity, and Sprague-Dawley rats subjected to sustained exogenous bilirubin administration were more resistant to endotoxin (LPS)-induced hypotension and death compared with nonhyperbilirubinemic rats. LPS-stimulated production of nitric oxide (NO) was significantly decreased in hyperbilirubinemic rats compared with normal animals; this effect was associated with reduction of inducible NO synthase (NOS2) expression in renal, myocardial, and aortic tissues. Furthermore, NOS2 protein expression and activity were reduced in murine macrophages stimulated with LPS and preincubated with bilirubin at concentrations similar to that found in the serum of hyperbilirubinemic animals. This effect was secondary to inhibition of NAD(P)H oxidase since 1) inhibition of NAD(P)H oxidase attenuated NOS2 induction by LPS, 2) bilirubin decreased NAD(P)H oxidase activity in vivo and in vitro, and 3) down-regulation of NOS2 by bilirubin was reversed by addition of NAD(P)H. These findings indicate that bilirubin can act as an effective agent to reduce mortality and counteract hypotension elicited by endotoxin through mechanisms involving a decreased NOS2 induction secondary to inhibition of NAD(P)H oxidase

    Forward pi^0 Production and Associated Transverse Energy Flow in Deep-Inelastic Scattering at HERA

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    Deep-inelastic positron-proton interactions at low values of Bjorken-x down to x \approx 4.10^-5 which give rise to high transverse momentum pi^0 mesons are studied with the H1 experiment at HERA. The inclusive cross section for pi^0 mesons produced at small angles with respect to the proton remnant (the forward region) is presented as a function of the transverse momentum and energy of the pi^0 and of the four-momentum transfer Q^2 and Bjorken-x. Measurements are also presented of the transverse energy flow in events containing a forward pi^0 meson. Hadronic final state calculations based on QCD models implementing different parton evolution schemes are confronted with the data.Comment: 27 pages, 8 figures and 3 table

    Antimalarial drug artemether inhibits neuroinflammation in BV2 microglia through Nrf2-dependent mechanisms

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    Artemether, a lipid-soluble derivative of artemisinin has been reported to possess anti-inflammatory properties. In this study, we have investigated the molecular mechanisms involved in the inhibition of neuroinflammation by the drug. The effects of artemether on neuroinflammation-mediated HT22 neuronal toxicity were also investigated in a BV2 microglia/HT22 neuron co-culture. To investigate effects on neuroinflammation, we used LPS-stimulated BV2 microglia treated with artemether (5-40µM) for 24 hours. ELISAs and western blotting were used to detect pro inflammatory cytokines, nitric oxide, PGE2, iNOS, COX-2 and mPGES-1. BACE-1 activity and Aβ levels were measured with ELISA kits. Protein levels of targets in NF-kappaB and p38 MAPK signalling, as well as HO-1, NQO1 and Nrf2 were also measured with western blot. NF-kappaB binding to the DNA was investigated using EMSA. MTT, DNA fragmentation and ROS assays in BV2-HT22 neuronal co-culture were used to evaluate the effects of artemether on neuroinflammation-induced neuronal death. The role of Nrf2 in the anti-inflammatory activity of artemether was investigated in BV2 cells transfected with Nrf2 siRNA. Artemether significantly suppressed pro-inflammatory mediators (NO/iNOS, PGE2/COX-2/mPGES-1, TNFα, and IL-6), Aβ and BACE-1 in BV2 cells following LPS stimulation. These effects of artemether were shown to be mediated through inhibition of NF-kappaB and p38MAPK signalling. Artemether produced increased levels of HO-1, NQO1 and GSH in BV2 microglia. The drug activated Nrf2 activity by increasing nuclear translocation of Nrf2 and its binding to antioxidant response elements in BV2 cells. Transfection of BV2 microglia with Nrf2 siRNA resulted in the loss of both anti-inflammatory and neuroprotective activities of artemether. We conclude that artemether induces Nrf2 expression and suggest that Nrf2 mediates the anti-inflammatory effect of artemether in BV2 microglia. Our results suggest that this drug has a therapeutic potential in neurodegenerative disorders

    Long-term outcomes of chimney endovascular aneurysm repair procedure for complex abdominal aortic pathologies

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    Objective: The aim of this study was to update our earlier experience and to evaluate long-term outcomes of chimney endovascular aortic repair performed for selected cases with complex abdominal aortic aneurysm. Methods: A single-center retrospective cohort study was conducted on 51 consecutive patients who underwent chimney endovascular aortic repair procedure, deemed unfit for open surgical repair and fenestrated endovascular aneurysm repair, from October 2009 to November 2019. Kaplan-Meier analyses were used to assess the estimated overall survival, freedom from aneurysm related mortality, freedom from reintervention, freedom from target vessel instability, and freedom from type Ia endoleaks. Results: Fifty-one patients (mean age, 77.1 ± 7.5 years) with a mean preoperative maximum aneurysm diameter of 74.2 ± 20.1 mm were included. Mean follow-up duration was 48.6 months (range, 0-136 months). Estimated overall survival at 5 and 7 years was 36.3% ± 7.1% and 18.3% ± 6.0%, respectively. Freedom from aneurysm-related mortality was 88.6% ± 4.9% at 7 years. Estimated freedom from type Ia endoleaks at 7 years was 91.8% ± 3.9%. A total of 21 late reinterventions were performed in 17 patients (33%). Most of them were performed to treat type II endoleaks with sac growth (47.6%; n = 10) and type Ib endoleak (23.8%; n = 5). Estimated freedom from reintervention at 7 years was 56.3% ± 7.9%. Estimated freedom from target vessel instability at 7 years was 91.5% ± 4.1%. Conclusions: The 7-year results of chimney endovascular aortic repair procedures performed in our center confirm the long-term safety and effectiveness of this technique in a series of high-risk patients with large aneurysms. The present study has, to the best of our knowledge, the longest follow-up for patients treated with chimney endovascular aortic repair, and it provides data to the scarce literature on the long-term outcomes of this procedure, showing acceptable to good long-term results

    Spatio-Temporal Image-Based Encoded Atlases for EEG Emotion Recognition

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    Emotion recognition plays an essential role in human-human interaction since it is a key to understanding the emotional states and reactions of human beings when they are subject to events and engagements in everyday life. Moving towards human-computer interaction, the study of emotions becomes fundamental because it is at the basis of the design of advanced systems to support a broad spectrum of application areas, including forensic, rehabilitative, educational, and many others. An effective method for discriminating emotions is based on ElectroEncephaloGraphy (EEG) data analysis, which is used as input for classification systems. Collecting brain signals on several channels and for a wide range of emotions produces cumbersome datasets that are hard to manage, transmit, and use in varied applications. In this context, the paper introduces the Empátheia system, which explores a different EEG representation by encoding EEG signals into images prior to their classification. In particular, the proposed system extracts spatio-temporal image encodings, or atlases, from EEG data through the Processing and transfeR of Interaction States and Mappings through Image-based eNcoding (PRISMIN) framework, thus obtaining a compact representation of the input signals. The atlases are then classified through the Empátheia architecture, which comprises branches based on convolutional, recurrent, and transformer models designed and tuned to capture the spatial and temporal aspects of emotions. Extensive experiments were conducted on the Shanghai Jiao Tong University (SJTU) Emotion EEG Dataset (SEED) public dataset, where the proposed system significantly reduced its size while retaining high performance. The results obtained highlight the effectiveness of the proposed approach and suggest new avenues for data representation in emotion recognition from EEG signals
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