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This genus was speculated to have same energy pathway like ureaplasma, by absorbing excessive urea from environment and utilize urea hydrolysis to generate energy. So it was believed to be responsible for urea hydrolysis mechanism mentioned above. This SBR showed stable partial nitritation and high urea removal efficiency for treating urea wastewater, which was obviously feasible as the pretreatment process for subsequent ANAMMOX.The widespread use of pesticides has received increasing attention in regulatory agencies because their extensive overuse and various adverse effects on all living organisms. Organizations such as EPA and ECHA have published laws that pesticides should be fully evaluated before bring them to market. In the present study, we evaluated the pesticides toxicity using the Quantitative Structural-Activity Relationship (QSAR) method. The models for the single class pesticides (herbicides, insecticides and fungicides) as well as the general class pesticides (the combined dataset plus some microbicides, molluscicides, etc.) were developed using the Genetic Algorithm and Multiple Linear Regression method. The internal and external validation results suggested that all the obtained models were stable and predictive. According to the modeling descriptors, the lipophilic descriptors contributed positively while all the electrotopological state descriptors showed a negative contribution, their presences in every model verified the conspicuous influence of molecular lipophilicity and hydrophilicity on the pesticides toxicity. However, the influence of topological structure descriptors was different and varies with the physiochemical information they encode. Finally, the models presented in this paper would help assess the pesticides toxicity against Americamysis bahia, shorten test time, and reduce the cost of pesticides risk assessment.The degradation of fluopyram (FLP) was investigated under ozone-microbubble treatment (OMBT). Kinetic models were established to study the influence of three treatments ozonated water, microbubbles (MCB), and OMBT. FLP degraded completely in OMBT, and a clearance rate of 89.8-100% was achievable. Three direct transformation products [product 1 (F1), product 2 (F2), and product 3(F3)] were isolated and identified using a hybrid ion trap-orbitrap mass spectrometer. Moreover, a transformation theory of FLP degradation was developed according to targeted fragmentation, accurate mass measurements, and degradation profiles. These analyses showed that the products originated from a series of chemical reactions involving dechlorination, hydroxyl substitution, cleavage and oxidation, and were further confirmed based on molecular electrostatic potential and molecular orbital theory. In addition, the stability and toxicity of FLP and its transformation products were tested using the Toxicity Estimation Software Tool (T.E.S.T.) and the Ecological Structure Activity Relationships (ECOSAR) program. Products F1, F2 and F3 were found to be toxic substances, but their toxicity to aquatic organisms was lower than that of FLP. However, they were more toxic to rats than FLP, and their physicochemical properties were more stable. Overall, OMBT is a highly effective method for FLP removal during wastewater treatment.Benzo(a)pyrene (BaP) is a highly persistent biohazard polyaromatic hydrocarbon and often reported to be present in soils co-contaminated with heavy metals. The present study explains the rhizodegradation of BaP using bacterial consortium in the rhizosphere of Melia azedarach, along with a change in taxonomical and functional properties of the rhizosphere microbiome. The relative abundance of most dominant phylum Proteobacteria was 2% higher with BaP, while in the presence of both BaP and Cd, its abundance was 2.2% lower. Functional metagenome analysis also revealed the shifting of microbial community and functional gene abundance in the favor of xenobiotic compound degradation upon augmentation of bacterial consortium. Interestingly, upon the addition of BaP the range of functional abundance for genes of PAH degradation (0.165-0.19%), was found to be decreasing. However, augmentation of a bacterial consortium led to an increase in its abundance including genes for degradation of benzoate (0.55-0.64%), toluene (0.2-0.22%), naphthalene (0.25-0.295%) irrespective of the addition of BaP and Cd. Moreover, under greenhouse condition, the application of M. azedarach-bacterial consortium enhanced the degradation of BaP in the rhizosphere (88%) after 60 days, significantly higher than degradation in bulk soil (68.22%). The analysis also showed an increase in degradation of BaP by 15% with plant-native microbe association than in bulk soil. Therefore, the association of M. azedarach-bacterial consortium enhanced the degradation of BaP in soil along with the taxonomical and functional attributes of the rhizosphere microbiome.Tetrahydrofuran (THF) is a common highly toxic cyclic aliphatic ether that frequently exists in waste gases. Removal of gaseous THF is a serious issue with important environmental ramifications. [https://www.selleckchem.com/products/ziprasidone.html this website] A novel three-phase airlift bioreactor (TPAB) loaded with immobilized cells was developed for efficient THF removal from gas streams. An effective THF-degrading transformant, Pseudomonas oleovorans GDT4, which contains the pTn-Mod-OTc-gfp plasmid and was tagged with a green fluorescent protein (GFP), was constructed. Continuous treatment of THF-containing waste gases was succeeded by the GFP-labelled cells immobilized with calcium alginate and activated carbon fiber in the TPAB for 60 days with &gt;90% removal efficiency. The number of fluorescent cells in the beads reached 1.7 × 1011 cells·g-1 of bead on day 10, accounting for 83.3% of the total number of cells. The amount further increased to 3.0 × 1011 cells·g-1 of bead on day 40. However, it decreased to 2.5 × 1011 cells·g-1 of bead with a substantial increase in biomass in the liquid because of cell leakage and hydraulic shock. PCR-DGGE revealed that P. oleovorans was the dominant microorganism throughout the entire operation. The maximum elimination capacity was affected by empty bed residence time (EBRT). The capacity was only 25.9 g m-3·h-1 at EBRT of 80 s, whereas it reached 37.8 g m-3·h-1 at EBRT of 140 s. This work provides an alternative method for full-scale removal of gaseous THF and presents a useful tool for determining the biomass of a specific degrader in immobilized beads.