68 research outputs found

    An innovative respirometric method to assess the autotrophic active fraction: Application to an alternate oxic-anoxic MBR pilot plant

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    An innovative respirometric method was applied to evaluate the autotrophic active fraction in an alternate anoxic/oxic membrane bioreactor (MBR) pilot plant. The alternate cycle (AC) produces a complex microbiological environment that allows the development of both autotrophic and heterotrophic species in one reactor. The present study aimed to evaluate autotrophic and heterotrophic active fractions and highlight the effect of different aeration/non aeration ratios in a AC-MBR pilot plant using respirometry. The results outlined that the autotrophic active fraction values were consistent with the nitrification efficiency and FISH analyses, which suggests its usefulness for estimating the nitrifying population. Intermittent aeration did not significantly affect the heterotrophic metabolic activity but significantly affected the autotrophic biomass development. Finally, the heterotrophic active biomass was strongly affected by the wastewater characteristics, whereas the resultant autotrophic biomass was considerably affected by the duration of the aerated phase

    The Open Universe survey of Swift-XRT GRB fields: a complete sample of HBL blazars

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    We have analysed all the X-ray images centred on Gamma Ray Bursts generated by Swift over the last 15 years using automatic tools that do not require any expertise in X-ray astronomy, producing results in excellent agreement with previous findings. This work, besides presenting the largest medium-deep survey of the X-ray sky and a complete sample of blazars, wishes to be a step in the direction of achieving the ultimate goal of the Open Universe Initiative, that is to enable non expert people to fully benefit of space science data, possibly extending the potential for scientific discovery, currently confined within a small number of highly specialised teams, to a much larger population. We have used the Swift_deepsky Docker container encapsulated pipeline to build the largest existing flux-limited and unbiased sample of serendipitous X-ray sources. Swift_deepsky runs on any laptop or desktop computer with a modern operating system. The tool automatically downloads the data and the calibration files from the archives, runs the official Swift analysis software and produces a number of results including images, the list of detected sources, X-ray fluxes, SED data, and spectral slope estimations. We used our source list to build the LogN-LogS of extra-galactic sources, which perfectly matches that estimated by other satellites. Combining our survey with multi-frequency data we selected a complete radio flux-density limited sample of High Energy Peaked (HBL) blazars.Comment: Accepted for publication in A&A. 8 pages, 7 figure

    Open Universe for Blazars: A new generation of astronomical products based on 14 years of Swift -XRT data

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    Aims. Open Universe for Blazars is a set of high-transparency multi-frequency data products for blazar science, and the tools designed to generate them. Blazars are drawing growing interest following the consolidation of their position as the most abundant type of source in the extragalactic very high-energy γ-ray sky, and because of their status as prime candidate sources in the nascent field of multi-messenger astrophysics. As such, blazar astrophysics is becoming increasingly data driven, depending on the integration and combined analysis of large quantities of data from the entire span of observational astrophysics techniques. The project was therefore chosen as one of the pilot activities within the United Nations Open Universe Initiative, whose objective is to stimulate a large increase in the accessibility and ease of utilisation of space science data for the worldwide benefit of scientific research, education, capacity building, and citizen science. Methods. Our aim is to deliver innovative data science tools for multi-messenger astrophysics. In this work we report on a data analysis pipeline called Swift-DeepSky based on the Swift XRTDAS software and the XIMAGE package, encapsulated into a Docker container. Swift-DeepSky downloads and reads low-level data, generates higher level products, detects X-ray sources, and estimates several intensity and spectral parameters for each detection, thus facilitating the generation of complete and up-to-date science-ready catalogues from an entire space-mission data set. Results. As a first application of our innovative approach, we present the results of a detailed X-ray image analysis based on Swift-DeepSky that was run on all Swift-XRT observations including a known blazar, carried out during the first 14 years of operations of the Neil Gehrels Swift Observatory. Short exposures executed within one week of each other have been added to increase sensitivity, which ranges between ∼1 × 10-12 and ∼1 × 10-14 erg cm-2 s-1 (0.3-10.0 keV). After cleaning for problematic fields, the resulting database includes over 27 000 images integrated in different X-ray bands, and a catalogue, called 1OUSXB, that provides intensity and spectral information for 33 396 X-ray sources, 8896 of which are single or multiple detections of 2308 distinct blazars. All the results can be accessed online in a variety of ways, from the Open Universe portal through Virtual Observatory services, via the VOU-Blazar tool and the SSDC SED builder. One of the most innovative aspects of this work is that the results can be easily reproduced and extended by anyone using the Docker version of the Swift-DeepSky pipeline, which runs on Linux, Mac, and Windows machines, and does not require any specific experience in X-ray data analysis.Fil: Giommi, Paolo. Università di Roma; Italia. International Center For Relativistic Astrophysics; Italia. Universitat Technical Zu Munich; AlemaniaFil: Brandt, C. H.. International Center For Relativistic Astrophysics; Italia. Jacobs University; AlemaniaFil: Barres de Almeida, U.. International Center For Relativistic Astrophysics; Italia. Centro Brasileiro de Pesquisas Físicas; BrasilFil: Pollock, A. M. T.. University of Sheffield; Reino UnidoFil: Arneodo, F.. New York University Abu Dhabi; Arabia SauditaFil: Chang, Y. L.. International Center For Relativistic Astrophysics; ItaliaFil: Civitarese, Enrique Osvaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: de Angelis, Maria Cruz. Università di Roma; ItaliaFil: D'Elia, V.. Space Science Data Center; Italia. Osservatorio Astronomico di Roma; ItaliaFil: Del Rio Vera, J.. United Nations Office for Outer Space Affairs; AustraliaFil: Di Pippo, S.. United Nations Office for Outer Space Affairs; AustraliaFil: Middei, Riccardo. Università di Roma; ItaliaFil: Penacchioni, Ana Virginia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Física La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Física La Plata; ArgentinaFil: Perri, M.. Osservatorio Astronomico di Roma; Italia. Space Science Data Center; ItaliaFil: Ruffini, Remo. International Center For Relativistic Astrophysics; ItaliaFil: Sahakyan, Narek. International Centre For Relativistic Astrophysics Network; ArmeniaFil: Turriziani, Sara. Computational Astrophysics Laboratory; Japó

    Anti‑algal activity of the 12‑5‑12 gemini surfactant results from its impact on the photosynthetic apparatus

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    A rapid amplification of algal population has a negative impact on the environment and the global economy. Thus, control of algal proliferation is an important issue and effective procedures which reduce algal blooms and control algal fouling are highly desired. Gemini surfactants are considered to have a low environmental impact, therefore they seem to be a promising group of detergents which could reduce algal blooms in water systems. Furthermore, due to their emulsifying properties they could replace algaecides added to antifouling paints and decrease algae adhesion to various surfaces. In this study the toxic effect of the 12-5-12 gemini surfactant was investigated on Chlorella cells and close attention was paid to a potential mechanism of its action. At the high cell density (10.05 × 107 cells/mL) a dose-dependent cell death was found and the IC50 value was reached at the concentration of 19.6 µmol/L after 72-h exposure to the surfactant. The decrease in chlorophyll autofluorescence shows that the photosynthetic apparatus seems to be the target of the tested compound. The presented studies indicate that gemini surfactants could effectively reduce algal blooms in water systems, and if added to paints, they could decrease algal growth on external building walls or other water immersed surfaces

    An iconic case of pigmentary glaucoma: brief review of the literature

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    Pigment dispersion syndrome and pigmentary glaucoma are two conditions characterized by pigment dispersion originating from the posterior part of the iris and its accumulation on the trabecular meshwork, corneal endothelium, and anterior surface of the lens. The pigment on the trabecular meshwork can cause chronic inflammation with a secondary reduction of its function and an increase in intraocular pressure. The case presented represents a typical example of pigmentary glaucoma in a myopic patient in which all the signs, symptoms, and complications typical of these pathologies were present. We report and describe an 8-year-long follow-up period with clinical and instrumental examinations

    Human amniotic membrane patch and platelet-rich plasma to promote retinal hole repair in a recurrent retinal detachment

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    Purpose: To present a modified surgical technique, based on a combination of human amniotic membrane (hAM) patch and autologous Platelet-rich plasma (PRP) in a case of recurrent retinal detachment (RRD) due to a perivascular retinal hole over an area of staphyloma in an eye with pathologic myopia. Methods: Presenting the surgical technique with the disposal of surgical video. After performing 23-gauge pars plana vitrectomy (PPV) the hAM patch was inserted under the neuroretina through the perivascular hole and PRP was injected on top to speed up the closure of the hole. To complete the surgical procedure High Viscosity Silicon oil (5000cst) was used as tamponade. The patient was prescribed to maintain a face-down position for the first 3 days after the operation. Follow-up was evaluated through Optical coherence tomography (OCT) scans. Results: The 3 days postoperative OCT showed a flat retina with the filling of the myopic staphyloma. The hAM patch was well positioned and the retinal hole could not be identified. At 6 weeks from intervention, the site of the retinal hole at OCT scan was covered by new tissue. Silicone oil was removed 3 months later with no recurrence. Conclusion: hAM transplantation is a novel technique in case of retinal detachment recurrences to seal retinal holes over high myopic chorioretinal atrophy. The adjunctive use of PRP and high viscosity silicon oil allows to reducing the standard face-down positioning timing, representing a valid solution for elderly patients who have difficulties maintaining the position for long periods

    Nab-Paclitaxel related cystoid macular edema

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    Nab-paclitaxel is a chemotherapeutic drug used to treat various solid malignant tumors. It was conceived with a solvent free formulation to overcome toxicity events and hypersensitivity reactions associated with paclitaxel. However, it still carries ocular adverse effects. The present review examines nab-paclitaxel related cystoid macular edema (CME) and the available therapeutic options
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