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A bacterial strain capable of degrading di(2-ethylhexyl) phthalate (DEHP) from the artificially contaminated water (with over 90% removal within 5 days of incubation) was isolated from the activated sludge obtained from a regional wastewater treatment plant in Macau Special Administrative Region, China. The isolate was identified as Acinetobacter sp. SN13 by the 16S rRNA gene sequence analysis. Two major experimental parameters, temperature (25, 30, 35 °C) and pH (3–9), were further optimized to enhance the biodegradation efficiency for DEHP. The optimal temperature was 30 °C while there were no significant differences for the pH range tested, 6–9 (p = 0.87). The growth kinetics of this indigenous isolate on DEHP followed the inhibition model, with the maximum degradation rate, the half saturation constant, and the inhibition constant of 124.8 mg l −1 day −1 , 272.3 mg l −1 , and 720.5 mg l −1 , respectively. The inhibition model for the specific growth rate was also simulated using Matlab software, and the respective maximum specific growth rate, half saturation constant, and inhibition constant were 0.1192 day −1 , 137.6 mg l −1 , and 850.3 mg l −1 . The highest degradation rate was achieved when the initial concentration of DEHP was 400 mg l −1 . Ferric ion (Fe 3+ at 100–1000 μg l −1 ) showed the stimulatory effect on the DEHP biodegradation, while Mn 2+ stimulated the biodegradation at lower concentrations (100 μg l −1 ) but inhibited at higher concentrations (500–1000 μg l −1 ). The respective DEHP degradation pathway for the isolate is also proposed by the identification of the following intermediates: mono-(2-ethylhexyl) phthalate (MEHP), phthalic acid (PA), protocatechuate, β-carboxy- cis , cis -muconic acid, and 3-katoadipate. [ABSTRACT FROM AUTHOR]

A rotating suspension cartridge reactor immobilized with white-rot fungus Phanerochaete chrysosporium was employed to treat synthetic wastewater containing 1000 μg l −1 of the recalcitrant pharmaceutically active compound carbamazepine. The reactor was continuously operated for 160 days under non-sterile conditions. After one month of fungal adaptation, the removal efficiency for carbamazepine exceeded 90% through such strategies as the immobilization of P. chrysosporium on the polyurethane foam cubes (1.0 × 1.0 × 1.0 cm 3 ), the pattern of liquid/air flow inside the cartridge created through the application of intermittent operational mode, and the gradual cut of external carbon source loading in the influent. Both nutrients and oxygen were effectively transferred to fungi, which contributed to the excellent bioreactor treatment performance for the long-term continuous operation. The bacterial contamination occurring in the bioreactor was effectively suppressed, providing a feasible alternative to treat recalcitrant compounds under non-sterile conditions. [ABSTRACT FROM AUTHOR]

Di (2-ethylhexyl) phthalate (DEHP) and dibutyl phthalate (DBP) are the most widely used plasticizers for agricultural mulching films and one of the most common organic pollutants in black soil. However, little is known about the effect of these two contaminants on nitrification in black soil. This study investigated the changes of 20 mg/kg DEHP and DBP on the diversity of nitrification microbial communities, the abundance of ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) related genes, and the activities of key enzymes involved in nitrification. During ammonia oxidation, DEHP and DBP had uncompetitive inhibition of urease, reducing the copy number of amoA gene, and microorganisms (Azoarcus , Streptomyces and Caulobacter) would use inorganic nitrogen as a nitrogen source for physiological growth. During nitrite oxidation, the copy number of nxrA gene also reduced, and the relative abundance of chemoautotrophic nitrifying bacteria (Nitrosomonas and Nitrobacter) decreased. Moreover, the path analysis results showed that DEHP and DBP mainly directly or indirectly affect AOB and NOB through three ways. These results help better understand the ecotoxicological effects of DEHP and DBP on AOB and NOB in black soil. [Display omitted] • DEHP and DBP have a negative competitive impact on the ammonia oxidation. • DEHP and DBP have a greater impact on inorganic nitrogen than enzymes. • Actinobacteria may be affected first and play a major role in microbial functions. [ABSTRACT FROM AUTHOR]

Abstract: A novel self-adaptive differential evolution (SADE) algorithm is proposed in this paper. SADE adjusts the mutation rate F and the crossover rate adaptively, taking account of the different distribution of population. In order to balance an individual’s exploration and exploitation capability for different evolving phases, and are equal to two different self-adjusted nonlinear functions. Attention is concentrated on varying  and  dynamically with each generation evolution. SADE maintains the diversity of population and improves the global convergence ability. It also improves the efficiency and success rate and avoids the premature convergence. Simulation and comparisons based on test-sets of CSPs demonstrate the effectiveness, efficiency and robustness of the proposed algorithm. [Copyright &y& Elsevier]

Increased model complexity and data quantities have raised the computing power requirement for efficient evapotranspiration (ET) estimation. A cloud-based service is presented to encapsulate and publish the ETWatch modeling algorithms as web application programming interfaces (APIs) in a consistent style to provide extensible model calculation service and data storage service in a cloud platform for water managers and stakeholders. The prototype system, named ETWatch Cloud allows users to rapidly and easily set up an ET generation project for any region of interest by invoking APIs directly to produce ET data using a web browser or local integrated development environment. The case study demonstrates that ETWatch Cloud can provide a highly scalable and interoperable ET generation tool for stakeholders from ET community, helping to facilitate the application of remote sensing-based ET algorithms for water management in hydrology sector. • A new high scalability, easy interoperability, cloud-based for ET generation at reginal scale. • Encapsule and publish ETWatch modeling algorithm to web API in a consistent style. • A general solution for the publishing, running and management of modules in the cloud. • Provides stakeholders in the ET community and hydrology sector with an innovative tool. • Generate ET data without additional computing, storage, or algorithm development. [ABSTRACT FROM AUTHOR]

In this work, Caenorhabditis elegans was employed as an in vivo model to determine the toxic effects of atrazine at different concentrations. After the exposure period from the larval stage L1 to adulthood day 1, atrazine (10 mg/L) significantly decreased the body length and lifespan of nematodes. In addition, exposure to ≥0.01 mg/L atrazine remarkably increased the intestinal reactive oxygen species (ROS) levels and reduced locomotion behavior of nematodes, while exposure to ≥ 1 mg/L atrazine decreased the brood size of nematodes. Moreover, atrazine (0.001–0.1 mg/L) upregulated the expression levels of hsp-6::GFP and hsp-6 / 60 in nematodes, indicating the activation of mitochondrial unfolded protein response (mtUPR). On the contrary, atrazine (1–10 mg/L) downregulated the expression levels of hsp-6::GFP and hsp-6 / 60 in nematodes. Furthermore, mtUPR induction governed by the RNAi knockdown of atfs-1 could increase the vulnerability of nematodes against atrazine toxicity. Overall, our findings highlighted the dynamic responses of nematodes toward different concentrations of atrazine, which could be monitored using different sublethal endpoints as bioindicators. [Display omitted] • Dynamic response to atrazine could be monitored by different sublethal endpoints. • mt UPR was very sensitive to atrazine exposure. • mt UPR could provide a protective response to atrazine. [ABSTRACT FROM AUTHOR]