Bioremediation of Crude Oil Contaminated Desert Soil: Effect of Biostimulation, Bioaugmentation and Bioavailability in Biopile Treatment Systems

This work was aimed at evaluating the relative merits of bioaugmentation, biostimulation and surfactant-enhanced bioavailability of a desert soil contaminated by crude oil through biopile treatment. The results show that the desert soil required bioaugmentation and biostimulation for bioremediation of crude oil. The bioaugmented biopile system led to a total petroleum hydrocarbon (TPH) reduction of 77% over 156 days while the system with polyoxyethylene (20) sorbitan monooleate (Tween 80) gave a 56% decrease in TPH. The biostimulated system with indigenous micro-organisms gave 23% reduction in TPH. The control system gave 4% TPH reduction. The addition of Tween 80 led to a respiration rate that peaked in 48 days compared to 88 days for the bioaugmented system and respiration declined rapidly due to nitrogen depletion. The residual hydrocarbon in the biopile systems studied contained polyaromatics (PAH) in quantities that may be considered as hazardous. Nitrogen was found to be a limiting nutrient in desert soil bioremediation.United Arab Emirates University Research Sector (grant 03-7-12/02)

Alternatives to amine-based capture & new technologies

Large improvements in separations technology will require novel materials with enhanced properties and performance. The fundamental interlinks for success in merging synthesis and process incorporation are the structure, relevant physical/chemical properties, and performance of new materials. Specific materials with these interlinks are room-temperature ionic liquids (RTILs) and their polymers and composites. As a chemical platform, RTILs have an enormous range of structural variation that can provide the ability to "tune" their properties and morphology for a given application. Introduction of chemical specificity into the structure of RTIL-based materials is an additional key component. Membrane separation is the focus as a process for implementation. There have not been new materials successfully developed for this process in thirty years. For CO 2 capture, the target improvement in productivity is two orders of magnitude or more compared to commercial materials currently available.qscienc

Natural Gas Hydrates

Sir Humphry Davy witnessed the first chlorine hydrate crystallizing in 1811. Couple of century later his discovery, natural gas hydrates has begun to play an important role in energy business. From being a mere chemical curiosity, they have proven to be a nuisance for the natural gas industry. The problem of hydrate induced blockage in âwet gasâ flow systems has been widely reported and became a major flow assurance issue in the energy sector[1]. The importance of pipeline blockage increased in the 70âs when plugging of even the largest diameter pipelines from offshore, arctic fields or the wells from high-pressure underground storage facilities were reported. Studies over the past two decades showed that large gas hydrate plugs form most often after shut-in pipelines or wells begin to flow[2]. When a pipeline is shut-in, the fluid separates into the gas water and hydrocarbons as the temperature decreases[3]

Caractérisation morpho-pomologique de 23 accessions de citronnier de la collection El Menzeh de l’INRA Maroc

INRA Morocco has an important citrus collection located in several sites in the Kingdom. Citrus germplasm offers a large resource for selecting within local lemon accessions of genes related to disease resistance, stress, production, fruit quality. Which are essential for genetic improvement. Some potential varieties may be of interest to producers. In the present study, twenty-three accessions of a lemon tree (Citrus limon [L.] Burm. F.) planted at El Menzeh collection, are characterized according to the IPGRI and UPOV citrus descriptors. Morpho-pomological variables showed a significant difference between lemon accessions. Only the morphological parameters of leaves, fruits and fruit peel color showed a high variability. Chemical analysis of the juices revealed significant differences among accessions. The data showed that acidity ranged from 0.1% for Sweet and Butnal lemons to 6.6% for Kennedy. While, the Kerkachi, Butnal, Cascade and Allen lemon accessions had the highest levels of both sugar and juice. Likewise, the accessions Doux Acid, Dellys and Kennedy showed fruits with an important size. The fruits of Lisbon, Eureka, Corregia, Ba Ahmed and Valencia had fruits with a low number of seeds or seedless. Our study showed that there was an acceptable pomological variability among the accessions of lemons cultivated in Morocco. Butnal, Allen, Cascade, Sçweet Acid, Dellys, Kennedy, Lisbon, Eureka, Corregia, Ba Ahmed and Valencia lemons were promising in terms of quality. This makes them an important genetic resource for any future lemon program to expand varietal diversification for improved productivity and competitiveness of citrus. Finally, the use of molecular markers is necessary to complete this work and for better differentiation of closely related individuals.L’INRA Maroc dispose d’importantes collections d’agrumes localisées au niveau de plusieurs sites du royaume. Le germoplasme des agrumes offre une large gamme ressource de gènes liés à la résistance aux maladies, aux stress, à la production, à la qualité des fruits, etc., essentiels pour l’amélioration génétique. Certaines variétés potentielles pourraient intéresser les producteurs. Dans la présente étude, vingt-trois accessions de citronnier (Citrus limon [L.] Burm. F.) plantées au niveau de la collection d’El Menzeh, ont été caractérisés sur la base de la morphologie des feuilles, des fleurs et des fruits, à l’aide de descripteur prescrit pour les agrumes par (IPGRI) ‘International Plant Genetic Resources Institute’ et de l’Union de Protection des Obtentions végétales (UPOV). Les résultats de l’analyse de la variance des variables morpho-pomologiques ont montré une différence significative entre les accessions. Seulement les paramètres morphologiques des feuilles, des fruits ainsi que la couleur de l’écorce du fruit ont montré une variabilité élevée. De même, l’analyse chimique des jus a révélé des différences significatives entre les accessions. Les données ont démontré que l’acidité variait de 0,1 % pour les citrons Doux et Butnal à 6,6 % pour Kennedy. Tandis que les accessions de citrons Kerkachi, Butnal, Cascade et Allen présentaient les teneurs les plus élevées aussi bien en sucre qu’en jus. De même, les accessions Doux acide, Dellys et Kennedy montraient des fruits avec un calibre important. Enfin, les accessions Lisbon, Eureka, Corregia, Ba Ahmed et Valence possédaient des fruits avec un faible nombre de graines voir nul. Notre étude a démontré qu'il existait une variabilité pomologique acceptable parmi les accessions de citrons cultivés au Maroc. Les citrons Butnal, Allen, Cascade, Doux acide, Dellys, Kennedy, Lisbon, Eureka, Corregia, Ba Ahmed et Valence étaient prometteur en termes de qualité. Ce qui en fait une ressource génétique importante pour tout programme futur concernant les citrons pour élargir la diversification variétale pour amélioration de la productivité et la compétitivité des agrumes. Enfin, l’utilisation des marqueurs moléculaires est nécessaire pour compléter ce travail et pour une meilleure différenciation des individus étroitement apparentés

Isoprene-Degrading Bacteria from Soils Associated with Tropical Economic Crops and Framework Forest Trees

Isoprene, a volatile hydrocarbon emitted largely by plants, plays an important role in regulating the climate in diverse ways, such as reacting with free radicals in the atmosphere to produce greenhouse gases and pollutants. Isoprene is both deposited and formed in soil, where it can be consumed by some soil microbes, although much remains to be understood about isoprene consumption in tropical soils. In this study, isoprene-degrading bacteria from soils associated with tropical plants were investigated by cultivation and cultivation-independent approaches. Soil samples were taken from beneath selected framework forest trees and economic crops at different seasons, and isoprene degradation in soil microcosms was measured after 96 h of incubation. Isoprene losses were 4–31% and 15–52% in soils subjected to a lower (7.2 × 105 ppbv) and a higher (7.2 × 106 ppbv) concentration of isoprene, respectively. Sequencing of 16S rRNA genes revealed that bacterial communities in soil varied significantly across plant categories (framework trees versus economic crops) and the presence of isoprene, but not with isoprene concentration or season. Eight isoprene-degrading bacterial strains were isolated from the soils and, among these, four belong to the genera Ochrobactrum, Friedmanniella, Isoptericola and Cellulosimicrobium, which have not been previously shown to degrade isoprene

Estuarine sediment hydrocarbon-degrading microbial communities demonstrate resilience to nanosilver

Little is currently known about the potential impact of silver nanoparticles (AgNPs) on estuarine microbial communities. The Colne estuary, UK, is susceptible to oil pollution through boat traffic, and there is the potential for AgNP exposure via effluent discharged from a sewage treatment works located in close proximity. This study examined the effects of uncapped AgNPs (uAgNPs), capped AgNPs (cAgNPs) and dissolved Ag2SO4, on hydrocarbon-degrading microbial communities in estuarine sediments. The uAgNPs, cAgNPs and Ag2SO4 (up to 50 mg L−1) had no significant impact on hydrocarbon biodegradation (80–92% hydrocarbons were biodegraded by day 7 in all samples). Although total and active cell counts in oil-amended sediments were unaffected by silver exposure; total cell counts in non-oiled sediments decreased from 1.66 to 0.84 × 107 g−1 dry weight sediment (dws) with 50 mg L−1 cAgNPs and from 1.66 to 0.66 × 107 g−1 dws with 0.5 mg L−1 Ag2SO4 by day 14. All silver-exposed sediments also underwent significant shifts in bacterial community structure, and one DGGE band corresponding to a member of Bacteroidetes was more prominent in non-oiled microcosms exposed to 50 mg L−1 Ag2SO4 compared to non-silver controls. In conclusion, AgNPs do not appear to affect microbial hydrocarbon-degradation but do impact on bacterial community diversity, which may have potential implications for other important microbial-mediated processes in estuaries

Effects of a high-dose 24-h infusion of tranexamic acid on death and thromboembolic events in patients with acute gastrointestinal bleeding (HALT-IT): an international randomised, double-blind, placebo-controlled trial

Background: Tranexamic acid reduces surgical bleeding and reduces death due to bleeding in patients with trauma. Meta-analyses of small trials show that tranexamic acid might decrease deaths from gastrointestinal bleeding. We aimed to assess the effects of tranexamic acid in patients with gastrointestinal bleeding. Methods: We did an international, multicentre, randomised, placebo-controlled trial in 164 hospitals in 15 countries. Patients were enrolled if the responsible clinician was uncertain whether to use tranexamic acid, were aged above the minimum age considered an adult in their country (either aged 16 years and older or aged 18 years and older), and had significant (defined as at risk of bleeding to death) upper or lower gastrointestinal bleeding. Patients were randomly assigned by selection of a numbered treatment pack from a box containing eight packs that were identical apart from the pack number. Patients received either a loading dose of 1 g tranexamic acid, which was added to 100 mL infusion bag of 0·9% sodium chloride and infused by slow intravenous injection over 10 min, followed by a maintenance dose of 3 g tranexamic acid added to 1 L of any isotonic intravenous solution and infused at 125 mg/h for 24 h, or placebo (sodium chloride 0·9%). Patients, caregivers, and those assessing outcomes were masked to allocation. The primary outcome was death due to bleeding within 5 days of randomisation; analysis excluded patients who received neither dose of the allocated treatment and those for whom outcome data on death were unavailable. This trial was registered with Current Controlled Trials, ISRCTN11225767, and ClinicalTrials.gov, NCT01658124. Findings: Between July 4, 2013, and June 21, 2019, we randomly allocated 12 009 patients to receive tranexamic acid (5994, 49·9%) or matching placebo (6015, 50·1%), of whom 11 952 (99·5%) received the first dose of the allocated treatment. Death due to bleeding within 5 days of randomisation occurred in 222 (4%) of 5956 patients in the tranexamic acid group and in 226 (4%) of 5981 patients in the placebo group (risk ratio [RR] 0·99, 95% CI 0·82–1·18). Arterial thromboembolic events (myocardial infarction or stroke) were similar in the tranexamic acid group and placebo group (42 [0·7%] of 5952 vs 46 [0·8%] of 5977; 0·92; 0·60 to 1·39). Venous thromboembolic events (deep vein thrombosis or pulmonary embolism) were higher in tranexamic acid group than in the placebo group (48 [0·8%] of 5952 vs 26 [0·4%] of 5977; RR 1·85; 95% CI 1·15 to 2·98). Interpretation: We found that tranexamic acid did not reduce death from gastrointestinal bleeding. On the basis of our results, tranexamic acid should not be used for the treatment of gastrointestinal bleeding outside the context of a randomised trial