Enhanced pilot bioremediation of oily sludge from petroleum refinery disposal under hot-summer Mediterranean climate

Large pilot scale bioremediation approaches were implemented for the treatments of oily sludge (OS) characterised by alkaline pH (pH > 9), high concentration of metals (3% dry weight) and high total petroleum hydrocarbons content (TPH) rangingbetween 22,000 and 67,300 mg kg −1 from a Tunisian petroleum refinery. The treatments included bioaugmentation and biostimulation approaches with autochthonous isolated bacterial strains and consortia. Chemical, microbial, and ecotoxicological analyses were performed over a period of 180 days incubation. The bioremediation treatments favoured the development of Proteobacteria, Firmicutes and Bacteroidetes following an ecological succession of specialist bacterial groups, first associated to hydrocarbon degradation (e.g. Marinobacter and Alcanivorax) that resulted in a greater extent of TPH-degradation (up to 80%), and the selection of metal resistant bacteria including Hyphomonas, Phaeobacter, and Desulfuromusa. The best performances were obtained when bioaugmentation and biostimulation were combined. Over 90% of the TPH initial concentration was degraded over 180 days, which was accompanied with a 3-fold reduction of ecotoxicity. Our study demonstrates the efficacy of large pilot scale bioremediation of highly contaminated oily sludge, providing the evidence that the management of autochthonous microbial communities is of paramount importance for the success of the bioremediation process

Étude expérimentale de l’évolution en microcosme du chrome (VI) dans l’eau de mer et de ses effets sur la macrofaune et les bactéries indigènes de la Lagune de Bizerte (Tunisie)

La présente étude vise à comparer au laboratoire l’impact biologique du chrome hexavalent (Cr (VI)) présent dans le ciment non déchromé, et celui du chrome présent dans le ciment déchromé en considérant deux échelons trophiques de la lagune de Bizerte : les bactéries indigènes et la macrofaune représentée par la palourde Ruditapes decussatus.Dans deux types de microcosmes, l’un contenant de l’eau de mer seulement et l’autre contenant de l’eau de mer et du sédiment, la palourde européenne Ruditapes decussatus a été introduite à raison de 20 individus par aquarium. Quatre types d’aquarium ont été mis en place : un témoin (T), un aquarium contaminé par du ciment non déchromé (0,16 mg•L-1 de Cr (VI)), un contaminé par du ciment déchromé (0,05 mg•L-1 de Cr (VI)) et un contaminé par le dichromate de potassium (0,16 mg•L-1 de Cr (VI)). Deux replicats ont été réalisés pour chaque type de microcosme.La concentration du Cr (VI) dans l’eau a été mesurée par un dosage colorimétrique au début et après 96 heures d’expérimentation. La quantification des bactéries hétérotrophes a été évaluée par la méthode du Nombre le Plus Probable.Environ 80 % de la quantité du Cr (VI) présente dans le milieu ont été piégés dans les sédiments. Les ciments déchromés et non déchromés ont provoqué 100 % de mortalité chez les palourdes au bout de trois jours. Cependant, il n’a été observé que 40 % de mortalité dans le microcosme contaminé par le K2Cr2O7. Une diminution de la charge bactérienne totale a été observée au niveau des sédiments pour tous les traitements.On peut dire que la présence du sédiment a entraîné la diminution de la teneur du Cr (VI) dans l’eau et que malgré le déchromage du ciment, les deux types de ciment présentent un effet négatif sur les palourdes et les bactéries indigènes qui est plus marqué pour le ciment non déchromé.This laboratory study aimed to compare the biological impact of hexavalent chromium (Cr (VI)) present in chromium-containing treated cement and in chromium-free treated cement, by considering two trophic levels: the indigenous bacteria and macrofauna represented by the clam Ruditapes decussatus.In both types of microcosms, one containing only seawater and the other containing seawater and sediment, European clams Ruditapes decussatus were introduced at a density of 20 individuals per aquarium. Four types of aquariums were used: control (T), contaminated with non-dechromated cement (0.16 mg•L-1 of Cr (VI)), contaminated with dechromated cement (0.05 mg•L-1 of Cr (VI)), and one contaminated with potassium dichromate (0.16 mg•L-1 of Cr (VI)). Two replicates were performed for each type of microcosm. The Cr (VI) content of the water was determined with a colorimetric assay at the beginning of the experiment and after 96 h. The quantification of heterotrophic bacteria was performed by the Most Probable Number method.About 80% of the Cr (VI) present in the sediment-water aquarium was trapped in the sediment. Cement, non-dechromated and dechromated, caused 100% clam mortality after three days. However, only 40% clam mortality was observed in aquariums contaminated with K2Cr2O7. A decrease in total bacterial load was observed in the sediment for all treatments.We conclude that the presence of sediment in the aquariums led to a reduction of the Cr (VI) concentration in the overlying water, and that despite the chromium removal treatment effected on one of the cements, both types of cement had a negative impact on clams and indigenous bacteria, the impact being stronger for chromium-containing treated cement

First Report of the Winter Moth Operophtera brumata on Quercus canariensis and Q. afares in North West of Tunisia

Operophtera brumata is a newly detected moth in Tunisia. It is considered the most important leaffeeding pest infesting fruit trees and deciduous forests in northern Europe. A recent outbreak of the winter moths was observed between 2009 and 2014 in oak forest in the North West of Tunisia with a peak density in 2010-2011. O. brumata was observed on totally defoliated Quercus canariensis and Q. afares. In this paper, we present a first report of this pest

Influence of Bizerte city wastewater treatment plant (WWTP) on abundance and antibioresistance of culturable heterotrophic and fecal indicator bacteria of Bizerte Lagoon (Tunisia)

International audienc

First Report of Anacampsis scintillella on Halimium halimifolium in Sejnane (Bizerte, Tunisia)

At the beginning of April 2010, larvae of Orgyia trigotephras and Anacampsis scintillella caused severe plant defoliation in the region of Sejnane situated in the north of Tunisia. A. scintillella was observed on totally defoliated Halimium halimifolium plants. Larvae and pupae of A. scintillela were protected between two or three leaves of the host plant. Life history of A. scintillella is poorly studied, so far. In this paper, we presented a first report of this pest in Tunisia

Using Sarcocornia fruticosa and Saccharomyces cerevisiae to remediate metal contaminated sediments of the Ria Formosa lagoon (SE Portugal)

Ria Formosa lagoon is a coastal system in the south of Portugal, characterized by sediments contaminated from urban and industrial pollution emissions. In this study, sediments from two contrasted metal contamination level sites, colonized by Sarcocornia fruticosa were used in an on-site experimentation. The heavy metal removal efficiencies of S. fruticosa with and without bioaugmentation using autochthonous metal resistant isolated yeast (Saccharomyces cerevisiae) were compared. After 15 days of incubation, the total amount of metal concentration (Cd, Pb, Ni, Cr, and Cu) in sediments and plant matter were compared. We found a striking difference between heavily contaminated site and less contaminated site. Metal reductions in heavily contaminated site were generated more by S. fruticosa which was inoculated with S. cerevisiae. In the less contaminated sediments, the higher percentage reductions were achieved with S. fruticosa alone. Our results indicate that despite the phytoremediation potential of S. fruticosa, the addition of S. cerevisiae, increases the plant phytoremediation capacity. (C) 2018 European Regional Centre for Ecohydrology of the Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.info:eu-repo/semantics/publishedVersio

Tophaceous hip gouty arthritis revealing asymptomatic axial gout

Background: Hip and axial involvement is uncommon during gout and may raise diagnostic challenges. We describe a rare case of tophaceous hip gout which lead to the diagnosis of asymptomatic axial tophaceous gout at a single rheumatology center. Case presentation: A 35-year-old man, diagnosed with tophaceous polyarticular gout 14 years before presentation, consulted for a gout attack with reduced hip range‐of‐motion on physical examination and an increased serum uric acid level (655 µmol/L). He had been regularly taking colchicine, allopurinol (300 mg/j), and occasionally non-steroidal antiinflammatory drugs. Plain Radiography of the hips revealed bilateral circumferential joint space narrowing, subchondral erosions of the right acetabular, a calcified soft tissue tophus of the left hip and bilateral sacroiliitis grade IV. Computed tomography (CT) showed total ankylosis of the upper segments of both sacroiliac joints and bilateral hip joint space narrowing, subchondral geode eroding the right acetabulum. Moreover, CT revealed soft-tissue tophi involving the major trochanter of the left acetabulum, the right coxofemoral joint and lowest two levels of lumbar facet joints (L4-L5; L5-S1). A spinal and plevis magnetic resonance imaging (MRI) concluded on a gouty tophi, locolized bilaterally intraarticularly in the coxofemoral joints, gluteus medius bursae, lumbar facet joints (L4-L5; L5-S1), and cofirmed bilateral sacroiliitis. Conclusion: The axial and hip gouty arthritis are exceptionnel localisation. Radiographic imaging tools, mainly CT and MRI, may show the monosodium urate crystals and tophi that can contribute to bone and joint lesions of gout. They also allow the exclusion of other possible etiologies such as spondylodiscitis, infection, and neoplasia. Keywords: Gout, Tophi, Hip, Sacroiliitis, Lumbar spin

Portée pédagogique de Facebook à travers un programme de formation à base de caricatures

Contexte : Les technologies de l’information et de la communication (TIC) offrent des nouvelles avenues pédagogiques dont la portée demeure peu connue. Leur combinaison avec les caricatures, dotées d’une grande attractivité humoristique, pourrait favoriser la mémorisation et l’apprentissage. But : Évaluer la portée pédagogique de Facebook à travers un programme de formation basé sur les caricatures. Méthodes : Il s’agit d’une étude interventionnelle pré-expérimentale réalisée sur une période de 3 mois et incluant tous les internes et les résidents exerçant dans les services chirurgicaux et de réanimation. Après une évaluation initiale sur la transfusion sanguine, un groupe a été créé sur « Facebook » incluant tous les participants et via lequel 25 messages clés sous forme de caricatures ont été diffusés à raison de 3 messages par jour durant une période d’un mois. Finalement, l’évaluation initiale a été refaite. Le critère de jugement principal était le taux de bonne réponse (TBR) par participant. Résultats : Le taux de participation était de 84,6 % lors de la première évaluation et de 80,2 % lors de la deuxième. Au terme de notre intervention, le TBR par participant a augmenté de façon significative (de 52,3 à 66,5 % ; p < 0,001. Concernant les questions considérées comme dangereuses, le TBR a également significativement augmenté passant de 49,5 à 65,9 % avec p < 0,001. Conclusion : L’utilisation d’un moyen de communication tel que Facebook associé à un support d’information tel que les caricatures permettraient d’améliorer significativement les connaissances et constitueraient des outils pédagogiques intéressants et efficaces