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[Display omitted] • Fungal biodegradation of nicosulfuron was well studied using multi-omics approach. • A number of products and intermediates were newly identified by QTOF/MS. • Biodegradation occurred mainly by hydrolysis, hydroxylation, Smile rearrangement. • Biodegradation should be enzymatically regulated by GPI-T and P450s. • Physiological responses by metabolo-proteomics shall benefit biodegradation. The extensive use of sulfonylurea herbicides has raised major concerns regarding their long-term soil residues and agroecological risks despite their role in agricultural protection. Microbial degradation is an important approach to remove sulfonylureas, whereas understanding the associated biodegradation mechanisms, enzymes, and physiological responses remains incomplete. Based on the rapid biodegradation of nicosulfuron by typical fungal isolate Talaromyces flavus LZM1, the dependency on cellular accumulation and environmental conditions, e.g. pH and nutrient supplies, was shown in the study. The biodegradation of nicosulfuron occurred intracellularly and followed the cascade of reactions including hydrolysis, Smile contraction rearrangement, hydroxylation, and opening of the pyrimidine ring. Besides 2-amino-4,6-dimethoxypyrimidine (ADMP) and 2-aminosulfonyl-N,N-dimethylnicotinamide (ASDM), numerous products and intermediates were newly identified and the structural forms of methoxypyrimidine and sulfonylurea bridge contraction rearrangement are predicted to be more toxic than nicosulfuron. The biodegradation should be enzymatically regulated by glycosylphosphatidylinositol transaminase (GPI-T) and P450s, which were manifested with the significant upregulation in proteomics. It is the first time that the hydrolysis of nicosulfuron into ADMP and ASDM have been associated with GPI-T. The integrated pathways of biodegradation were further elucidated through the involvement of various active enzymes. Except for the enzymatic catalysis, the physiological responses verified by metabolo-proteomics were critical not only to regulate material synthesis, uptake, utilization, and energy transfer but also to maintain antioxidant homeostasis, biodegradability, and tolerance of nicosulfuron by the differentially expressed metabolites, such as acetolactate synthase and 3-isopropylmalate dehydratase. The obtained results would help understand the biodegradation mechanism of sulfonylurea from chemicobiology and enzymology and promote the use of fungal biodegradation in pollution rehabilitation. [ABSTRACT FROM AUTHOR]

Abstract Bi 0.3 Sb 1.7 Te 3 alloy particles were synthesized by casting and post-annealing techniques. HfO 2 nanoparticles were synthesized by hydrothermal method. HfO 2 nanoparticles with different volume percentage were dispersed into the Bi 0.3 Sb 1.7 Te 3 matrix by cryogenic ball milling. The distribution of HfO 2 nanoparticles in Bi 0.3 Sb 1.7 Te 3 matrix was confirmed by TEM. The crystallization was determined by XRD. The Bi 0.3 Sb 1.7 Te 3 /HfO 2 composite particles were hot pressed into pellets for thermoelectric property measurement by Physical Properties Measurement System (PPMS). The results showed that when the HfO 2 volume percentage was 0.4%, the composite showed the highest ZT value, which was 30% higher than pure Bi 0.3 Sb 1.7 Te 3. [ABSTRACT FROM AUTHOR]

Precise segmentation of total extraocular muscles (EOM) and optic nerve (ON) is essential to assess anatomical development and progression of thyroid-associated ophthalmopathy (TAO). To develop a semantic segmentation method to extract the total EOM and ON from orbital CT images in patients with suspected TAO. A total of 7879 images obtained from 97 subjects were enrolled in this study. 88 patients were randomly selected into the training/validation dataset, and the rest were put into the test dataset. Contours of the total EOM and ON in all patients were manually delineated by experienced radiologists as the ground truth. A three-dimensional(3D) end-to-end fully convolutional neural network called semantic V-net (SV-net) was developed for our segmentation task. Intersection over Union (IoU) was measured to evaluate the accuracy of the segmentation results, and Pearson correlation analysis was for evaluating the volumes measured from our segmentation results against those from the ground truth. It achieved an overall IoU of 0.8207 for the test dataset; the IoU was 0.7599 for the superior rectus muscle, 0.8183 for the lateral rectus muscle, 0.8481 for the medial rectus muscle, 0.8436 for the inferior rectus muscle and 0.8337 for the optic nerve. The volumes measured from our segmentation results agreed well with those from the ground truth(all R > 0.98, P < 0.0001). The qualitative and quantitative evaluations demonstrate excellent performance of our method in automatically extracting the total EOM and ON and measuring their volumes in orbital CT images. There is a great promise for clinical application to assess these anatomical structures for the diagnosis and prognosis of TAO. [ABSTRACT FROM AUTHOR]

A novel nanoblocks@nanoballs NiMnO 3 /Ni 6 MnO 8 electrode material was synthesized by one-step solvothermal–hydrothermal method, followed by thermal annealing. At the same time, electrode materials with different nanostructure were prepared by changing the volume ratio of deionied water and ethylene glycol. The results show that different structure has been gained including nanospheres, nanosheets and nanoblocks. When the deionied water: ethylene glycol = 1:1 (nanoblocks@nanoballs NiMnO 3 /Ni 6 MnO 8 composite structure), the electrode material has a maximum specific surface area of 55.3 m2 g−1. The electrode material exhibited outstanding electrochemical performance with specific capacitance reached 494.4 F g−1 at a current density of 1 A g−1 as well as superior cycling performance of 88.0% capacitance retention after 5000 cycles at 3 A g−1. Such excellent performance was due to the synergistic effective between the Ni 6 MnO 8 nanoballs and NiMnO 3 nanoblocks. Nanoballs structure will increase in specific surface area and redox reaction active sites, and the blocks structure acts as a holder to improved the cycle performance. The NiMnO 3 /Ni 6 MnO 8 become a promising candidate as next-generation electrode material for high-performance supercapacitors. • We had synthesis NiMnO 3 /Ni 6 MnO 8 material by one-step solvothermal method. • The electrode material has a novel nanoblocks@nanoballs structure. • The specific capacitance reached 494.4 F g−1 at current density with 1 A/g. • The capacitance retention is 88.0% after 5000 cycles at 3 A/g. [ABSTRACT FROM AUTHOR]

In the present investigation, microstructure, texture and mechanical properties of Mg-3Mn alloys fabricated by hot extrusion process with the extrusion temperatures of 250 °C and 300 °C were investigated. The results revealed that the samples exhibited the refined microstructure and weakened basal texture. Refined microstructure of the samples was attributed to the dynamic precipitates suppressing the recrystallization grain growth during extrusion process. Weakened basal texture of the samples was explained as a result of particle stimulated nucleation (PSN) promoted by coarsened Mn precipitates altering the texture of extruded profiles during recrystallization by orienting the c-axis of grains at an angle that favors basal slip activity. As a result, the samples exhibited the high tensile elongation and good yield strength at room temperature. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs) are a group of organic pollutants that have attracted much concerns of scientific community over the ubiquitous distribution, chemical persistence and toxicological risks in the environment. Though a great number of aerobic bacteria have been isolated for the rapid removal of PBDEs, the knowledge about biodegradation characteristics and mechanism is less provided yet. Herein, the congener-specificity of aerobic biodegradation of PBDEs by typical bacteria, i.e. B. xenovorans LB400 was identified with the different biodegradation kinetics, of which the changes were largely hinged on the bromination pattern. The more bromination isomerically at ortho -sites other than meta -sites or the single bromination at one of aromatic rings might always exert the positive effect. The biodegradation of PBDEs should be thermodynamically constrained to some extent because the calculated Gibbs free energy changes of initial dioxygenation by quantum chemical method increased with the increase of bromination. Within the transition state theory, the high correlativity between the apparent biodegradation rates and Gibbs free energy changes implied the predominance and rate-limiting character of initial dioxygenation, while the regioselectivity of dioxygenation at the ortho / meta -sites was also manifested for the more negative charge population. The molecular binding with the active domain of dioxygenase BphA1 in aerobe was firstly investigated using docking approach. As significantly illustrated with the positive relationship, the higher binding affinity with BphA1 should probably signify the more rapid biodegradation. Besides the edge-on π-π stacking of PBDEs with F227 or Y277 and π-cation formulation with histidines (H233, H239) in BphA1, the reticular hydrophobic contacts appeared as the major force to underpin the high binding affinity and rapid biodegradation of PBDEs. Overall, the experimental and theoretical results would not only help understand the aerobic biodegradation mechanism, but facilitate enhancing applicability or strategy development of engineering bacteria for bioremediation of PBDEs in the environment. [Display omitted] • Aerobic biodegradation of PBDEs by LB400 was shown with congener-specificity. • Thermodynamic changes of dioxygenation were correlated with biodegradation rates. • Dominance and regioselectivity at ortho / meta -sites was identified for dioxygenation. • Molecular binding with BphA1 in LB400 was firstly investigated by molecular docking. • Binding via hydrophobic contact, π-stacking or π-cation may underlie biodegradation. [ABSTRACT FROM AUTHOR]

• Fe(VI) could efficiently oxidize pyrene sorbed on montmorillonite, kaolinite and goethite. • Montmorillonite mediated the highest pyrene degradation efficiency. • Fe(V)/Fe(IV) species dominated the oxidation processes in pyrene degradation. • Two different phthalic acid producing pathways were identified. • Metal ions as Lewis acid on mineral surface assisted the Fe(VI) oxidation of pyrene. Ferrate (Fe(VI)) salts like K 2 FeO 4 are efficient green oxidants to remediate organic contaminants in water treatment. Minerals are efficient sorbents of contaminants and also excellent solid heterogeneous catalysts which might affect Fe(VI) remediation processes. By targeting the typical polycyclic aromatic hydrocarbon compound - pyrene, the application of Fe(VI) for oxidation of pyrene immobilized on three minerals, i.e., montmorillonite, kaolinite and goethite was studied for the first time. Pyrene immobilized on the three minerals was efficiently oxidized by Fe(VI), with 87%–99% of pyrene (10 μM) being degraded at pH 9.0 in the presence of a 50-fold molar excess Fe(VI). Different minerals favored different pH optima for pyrene degradation, with pH optima from neutral to alkaline following the order of montmorillonite (pH 7.0), kaolinite (pH 8.0), and goethite (pH 9.0). Although goethite revealed the highest catalytic activity on pyrene degradation by Fe(VI), the greater noneffective loss of the oxidative species by ready self-decay in the goethite system resulted in lower degradation efficiency compared to montmorillonite. Protonation and Lewis acid on montmorillonite and goethite assisted Fe(VI) oxidation of pyrene. The intermediate ferrate species (Fe(V)/Fe(IV)) were the dominant oxidative species accountable for pyrene oxidation, while the contribution of Fe(VI) species was negligible. Hydroxyl radical was involved in mineral-immobilized pyrene degradation and contributed to 11.5%–27.4% of the pyrene degradation in montmorillonite system, followed by kaolinite (10.8%–21.4%) and goethite (5.1%–12.2%) according to the hydroxyl radical quenching experiments. Cations abundant in the matrix and dissolved humic acid hampered pyrene degradation. Finally, two different degradation pathways both producing phthalic acid were identified. This study demonstrates efficient Fe(VI) oxidation of pyrene immobilized on minerals and contributes to the development of efficient environmentally friendly Fe(VI) based remediation techniques. [Display omitted] [ABSTRACT FROM AUTHOR]