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Harmful cyanobacterial blooms, which force us to develop economical and environmental friendly ways for eutrophication control, are recognized as a nuisance that cause negative impacts on natural resources and humans. In the current study, strain Bacillus amyloliquefaciens T1 with anti-cyanobacterial activity against bloom-forming cyanobacterium Microcystis aeruginosa 905 was isolated from an eutrophication pond in Wuhan, China, and was identified by 16S ribosomal DNA (rDNA) sequence analysis. B. amyloliquefaciens T1 cell-free filtrate at a concentration of 2 % ( v/ v) showed a strong anti-cyanobacterial effect against M. aeruginosa 905 (initial cell density was 1.0 × 10 cells mL), and a reduction of 99.4 % in cell number was observed after incubation for 6 days. The anti-cyanobacterial effect was in accordance with the spore number rather than the cell number of B. amyloliquefaciens T1, suggesting that M. aeruginosa 905 was indirectly affected by the secretion of anti-cyanobacterial active substances. In addition, the interactions of B. amyloliquefaciens T1 with other cyanobacteria and green algae indicated that M. aeruginosa 907, M. aeruginosa 908, M. aeruginosa 912, and M. aeruginosa 7806 were obviously suppressed, while Anabaena flosaquae 1092 and Chlorella pyrenoidosa 415 proved to be not susceptible. Effects of environmental factors showed that the best inhibition efficiency would be achieved at 30 °C and pH 9.0, and the solid B. amyloliquefaciens T1 agent of B. amyloliquefaciens T1 could selectively kill the wild cyanobacteria from a shallow eutrophic pond. Based on the results obtained from this study, the anti-cyanobacterial bacterium B. amyloliquefaciens T1 had a potential application for eutrophication control in the natural environment. [ABSTRACT FROM AUTHOR]

The utilization of metakaolin as concrete admixture is limited because of its higher water-consumption, which has an adverse effect on the workability and homogeneity of concrete. The work presented in this paper has been focused on the evaluation of the influence of the addition of surface treated metakaolin with coupling agent (MMK) on physical and mechanical properties of fresh and hardened concrete. Meanwhile, the effects of MMK are evaluated by drying shrinkage and electric flux test, and the properties of MMK paste are characterized by XRD and TG. It is shown that the concrete with MMK has excellent workability and compressive strength, compared to the mix with metakaolin. In addition, MMK modified concrete mixtures show better drying shrinkage and resistance to chloride penetrability. It is concluded that MMK can improve the rheological properties and reactivity of metakaolin effectively. In fresh concrete, the self-assembled membranes of coupling agent form on the surface of the particles through a condensation reaction. In hardened concrete, the introduction of silane provides the network of covalent coupling among the particles. Meanwhile, the hydrophilic nature of the silane improves the wettability of metakaolin, which increase the chance to react with Ca(OH). [ABSTRACT FROM AUTHOR]

A ribbon-cage-based triboelectric bearing (RTB) is proposed and applied to the fault diagnosis of rotating machinery. Teflon insulating coatings are sprayed on the surface of the ribbon cage, and interdigital electrodes are pasted on the inner side of the dust cover to form a triboelectric nanogenerator with a free-standing mode. Owing to the direct use of the existing structure of rolling bearings (the ribbon cage and dust cover), only an insulating film and electrodes are added, and the designed RTB has an ultra-compact structure. Based on the fabricated RTB prototype, the variations in output voltage and current with load resistance are tested, and the effects of design parameters (including dielectric layer material and thickness, number of electrode section pairs, and spraying of Teflon coatings) on output characteristics are discussed. Through varying-speed tests, charging of load capacitors, and effective driving of micro-powered electronic devices, the self-sensing and self-powering capabilities of the proposed RTB are confirmed. A gear transmission test bench is constructed to perform fault diagnosis of rotating machinery based on the RTB output current. Combined with the time–frequency transformation and a deep learning algorithm, typical faults of rotating machinery (including localized faults in gears and bearings) are classified and recognized. The results show that the RTB output current can be used to diagnose faults in rotating machinery, and the classification accuracy can exceed 90%, which is only slightly lower than that obtained from the analysis using vibration signals. The proposed RTB has good application prospects for the fault diagnosis of rotating machinery. [Display omitted] • A ribbon-cage-based triboelectric bearing (RTB) is proposed for fault diagnosis. • Only insulating film and electrodes are added, RTB has an ultra-compact structure. • Self-sensing and self-powering capabilities of RTB are confirmed by various tests. • The results show that the fault classification accuracy can exceed 90%. • The RTB has good application prospects for fault diagnosis of rotating machinery. [ABSTRACT FROM AUTHOR]

• Sparse learning based classification framework is proposed for health diagnostics. • SLBC can learn data-driven category-specific dictionaries from training samples. • SLBC achieves intelligent health diagnostics via a sparse classification strategy. • SLBC yields a recognition rate of 99.98% for planetary-bearing health diagnostics. • SLBC outperforms several advanced approaches with robust diagnostic performance. Planetary bearings are the most complex and challenging components for health diagnostics among wind turbine and helicopter planetary transmissions. Classical spectrum-based diagnosis strategy for planetary bearings faces great challenges because of complex structures and strong modulation effects. This work develops a novel sparse learning based classification (SLBC) framework with the overlapping segmentation strategy to address planetary bearing health diagnostics. Our SLBC framework learns the reconstructive dictionaries for sparse representations of vibration signals and achieves robust recognitions with the sparse approximation criterion. Firstly, the overlapping segmentation strategy is introduced to fully leverage periodic similarity features and augment training datasets for sparse dictionary learning. Then, the category-specific sub-dictionaries are learned from the augmented training datasets in a data-driven fashion via K-singular value decomposition. Finally, intelligent planetary-bearing fault recognition is achieved via the sparse approximation criterion. Our SLBC framework has been verified effective to classify three and four planetary-bearing health states with diagnostic accuracy of 100% and 99.98%, respectively. Comparisons with several advanced approaches have confirmed the superiority of SLBC in diagnostic accuracy, noise robustness, and computation time for planetary bearing health diagnostics. [ABSTRACT FROM AUTHOR]

• An enhanced dictionary learning-based sparse classification approach is proposed. • EDL-SC implements the data augmentation via overlapping segmentation strategy. • EDL-SC designs the data-driven whole dictionary via dictionary learning approach. • EDL-SC implements intelligent fault diagnosis via sparse classification approach. • EDL-SC outperforms several advanced methods for planetary bearing fault diagnosis. To date, planetary bearings remain challenging for machinery fault diagnosis because of their intricate kinematics, time-variant modulations, and strong interferences. To address this challenge, this study presents an enhanced dictionary learning based sparse classification (EDL-SC) approach to diagnose planetary bearings. Our main novelty lies in that the data augmentation and dictionary learning strategies are incorporated into our proposed EDL-SC approach, which can significantly enhance the representation ability and recognition ability for the sparse classification-based intelligent diagnosis criterion. Firstly, vibration data augmentation is implemented with an overlapping segmentation strategy to enhance the quality of training samples. Secondly, data-driven dictionary design is achieved by means of dictionary learning, which learns sub-dictionaries and adaptively designs the whole dictionary through considering both the inter-class and intra-class features. Thirdly, a sparse classification strategy is established for intelligent diagnostics by the aid of a discrimination criterion of minimal reconstruction errors. The feasibility and advantage of EDL-SC have been thoroughly evaluated with a challenging planetary bearing dataset. Experiment verification results of planetary bearing fault diagnosis indicate that EDL-SC obtains a superior diagnosis accuracy of 99.63%, strong robustness to noises, and competitive computation efficiency over advanced deep learning and sparse representation classification methods. This work can bring new insights for the application of sparse representation theory from the perspective of pattern recognition, and shows great potentials of EDL-SC for data-driven machinery fault diagnosis. [ABSTRACT FROM AUTHOR]

The retaining glycosyltransferase GalNAc-T2 is a member of a large family of human polypeptide GalNAc-transferases that is responsible for the post-translational modification of many cell-surface proteins. By the use of combined structural and computational approaches, we provide the first set of structural snapshots of the enzyme during the catalytic cycle and combine these with quantum-mechanics/ molecular-mechanics (QM/MM) metadynamics to unravel the catalytic mechanism of this retaining enzyme at the atomicelectronic level of detail. Our study provides a detailed structural rationale for an ordered bi-bi kinetic mechanism and reveals critical aspects of substrate recognition, which dictate the specificity for acceptor Thr versus Ser residues and enforce a front-face SNi-type reaction in which the substrate Nacetyl sugar substituent coordinates efficient glycosyl transfer. [ABSTRACT FROM AUTHOR]

Iron, as one of the essential mineral elements for algae growth, plays an extremely important role in the physiological processes such as plant photosynthesis, respiration, nitrogen fixation, protein and nucleic acid synthesis. In view of the fact that iron in different forms could be absorbed and utilized by algae, the existing forms and calculation approaches in the aquatic environment, the absorption mechanism by algea, and the effects on algae growth and microcystin synthesis were reviewed in this paper. The relevant microcystin synthesis genes and their expression under iron restricted conditions were summarized, and the research directions for harmful algal blooms regulation and control by ferritin genes were suggested. It was hoped to provide the reference for eutrophiction remediation technology. [ABSTRACT FROM AUTHOR]

Globotriose (Gal-α1, 4-Gal-β1, 4-Glc) is involved in binding with Shiga toxins (Stxs) produced by Shigella dysenteriae and certain pathogenic Escherichia coli strains which could cause severe gastroenteritis and hemolytic uremic syndrome (HUS). Thus, this trisaccharide group and its derivatives provide potentials in the development of carbohydrate-based diagnostic and therapeutic reagents against bacterial infection. Instead of the tedious chemical synthesis of globotriose or its glycoconjugates, we reported a multi-step (step-wise) enzymatic synthesis system containing glucosyltransferase (ApNGT, E.C. 4.3.3.5), β-1, 4-galactosyltransferase (LgtB, E.C. 2.4.1.22) and α-1, 4-galactosyltransferase (LgtC, E.C. 2.4.1.44) to produce globotriose-containing glycopeptides. In addition, based on the specific binding between Stxs and globotriose, a cost-efficient, convenient, ultra-sensitive and specific colorimetric biosensor was further constructed to detect Stxs using glycoconjugated Au@Fe-TFPA-COP (globotriose@Au@Fe-TFPA-COP) as a nanoenzyme catalyst. We estimate that this method conveniently applied in the detection of Stx-producing bacteria and associated infectious diseases. [Display omitted] • Globotriose-containing glycopeptides produced with a multi-enzyme system. • Globotriose conjugated onto the gold nanoparticle Au@FePor-TFPA-COP. • Shiga toxins were detected via Globotriose@Au@FePor-TFPA-COP conjugates. • Globotriose@Au@FePor-TFPA-COP showed good stability, and high sensitivity. [ABSTRACT FROM AUTHOR]

An isolated strain Streptomyces sp. HJC-D1 was applied to inhibit the growth of cyanobacterium Microcystis aeruginosa FACHB-905. The effect of Streptomyces sp. HJC-D1 culture broth on the cell integrity and physiological characteristics of M. aeruginosa FACHB-905 was investigated using the flow cytometry (FCM), enzyme activity and transmission electron microscopy (TEM) methods. Results showed that the growth of M. aeruginosa FACHB-905 was significantly inhibited, and the percentage of live cells depended on the culture broth concentration and exposure time. The activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) increased with exposure concentration and exposure time, and the significant increase of reactive oxygen species (ROS) led to the disruption of the subcellular structure of M. aeruginosa FACHB-905, and caused the increase of malondialdehyde (MDA). Furthermore, TEM observation suggested the presence of three stages (cell breakage, organelle release and cell death) for the cyanobactericidal process of Streptomyces sp. HJC-D1. Therefore, Streptomyces sp. HJC-D1 not only affected antioxidant enzyme activities and ROS level, but also destroyed the subcellular structure of M. aeruginosa FACHB-905, demonstrating excellent cyanobactericidal properties. [ABSTRACT FROM AUTHOR]

An isolated strain Streptomyces sp. HJC-D1 was applied to inhibit the growth of cyanobacterium Microcystis aeruginosa FACHB-905. The effect of Streptomyces sp. HJC-D1 culture broth on the cell integrity and physiological characteristics of M. aeruginosa FACHB-905 was investigated using the flow cytometry (FCM), enzyme activity and transmission electron microscopy (TEM) methods. Results showed that the growth of M. aeruginosa FACHB-905 was significantly inhibited, and the percentage of live cells depended on the culture broth concentration and exposure time. The activities of antioxidant enzymes including superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) increased with exposure concentration and exposure time, and the significant increase of reactive oxygen species (ROS) led to the disruption of the subcellular structure of M. aeruginosa FACHB-905, and caused the increase of malondialdehyde (MDA). Furthermore, TEM observation suggested the presence of three stages (cell breakage, organelle release and cell death) for the cyanobactericidal process of Streptomyces sp. HJC-D1. Therefore, Streptomyces sp. HJC-D1 not only affected antioxidant enzyme activities and ROS level, but also destroyed the subcellular structure of M. aeruginosa FACHB-905, demonstrating excellent cyanobactericidal properties. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the potential value of patient characteristics in predicting overall survival (OS) in patients with metastatic castration-resistant prostate cancer (mCRPC) treated with docetaxel-based thermotherapy. A total of 115 patients with mCRPC undergoing a docetaxel q3w regimen were enrolled in this study. A survival analysis was performed using the Kaplan-Meier method. Cox proportional hazards models were used to evaluate the prognostic value of all covariates for OS. OS was also analysed after stratifying patients according to the results of multivariate analysis. The median OS for the entire cohort was 17.0 months. The multivariate analysis showed that the prostate-specific antigen doubling time (PSADT), baseline haemoglobin (Hb) concentration, alkaline phosphatase (ALP) concentration, cycles of chemotherapy and time to castration resistance were independent prognostic factors of OS. According to the presence of PSADT <46.3 days and baseline ALP ≥110 IU l−1, all patients were divided into three risk groups: low-risk group (no risk factors), intermediate-risk group (one risk factor) and high-risk group (two risk factors). Median OSs for patients in low-, intermediate- and high-risk groups were 28.0 months (95% CI: 23.8-32.2), 21.0 months (95% CI: 18.9-23.1) and 11.0 months (95% CI: 7.6-14.4), respectively (P<0.001). In conclusion, PSADT, baseline Hb concentration, ALP concentration, cycles of chemotherapy and time to castration resistance were independent prognostic factors of OS in Chinese patients with mCRPC treated with docetaxel. PSADT combined with the baseline ALP concentration could be a useful risk stratification parameter for evaluating survival outcomes. [ABSTRACT FROM AUTHOR]

BACKGROUND: Increasing attention has been paid to enhancing biological control through habitat management in agricultural systems for enhanced pest management. Pest management benefits can be realised by intercropping, which can increase natural enemy abundance and, in turn, reduce pest abundance. In this study, the composition and temporal dynamics of arthropod communities in pear orchards when intercropped with aromatic plants were investigated, and the effectiveness and applicability of aromatic plants as intercrops for enhancing insect control were assessed. RESULTS: When compared with natural grasses or clean tillage, intercropping significantly reduced pest abundance and increased the ratio of natural enemies to pests. Intercropping also shortened the occurrence duration and depressed the incidence peak in annual dynamics curves of the pest subcommunity and the arthropod community, mainly because of the repellent effects of aromatic plants. Equally important, intercropping significantly reduced the numbers of major pests, such as Psylla chinensis, Aphis citricola and Pseudococcus comstocki, while their incidence period was delayed to varying degrees, and the numbers of their dominant natural enemies ( Coccinella septempunctata, Phytoseiulus persimilis and Chrysoperla sinica) increased. CONCLUSION: Intercropping with aromatic plants led to a considerable improvement in arthropod pest management by enhancing the activity of the beneficial arthropod community within the pear orchard ecosystem. Copyright © 2011 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Lake and reservoir's eutrophication and its produced microcystins (MCs) have enormous threats to ecological environment and human health. Because the conventional water pollution control techniques have definite limitations, it's quite urgent to develop new technique to remove the MCs from water environment. MCs can be effectively degraded by specific microbes, and its in- termediate and terminal products are non-toxic or low-toxic. This paper summarized the MCs-de- grading microbial strains, biodegradation processes, mechanisms, and affecting factors, degraded products and their structural characteristics, and the applications of MCs-degrading microbial strains in water environment restoration. The further research directions were also proposed. It was hoped that this review could provide technical ideas for restoring MCs-polluted lakes and reservoirs and en- suring drinking water safety in China. [ABSTRACT FROM AUTHOR]