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Development of functional fibers with efficient adsorption and catalytic properties is very important for their practical application in environmental remediation. In this study, carboxyl groups were firstly grafted onto the commercial poly(acrylonitrile) fiber (product designated as CPAN) and then used for in situ growth of manganese oxides (MnOx) nanospheres (product designated as MnOx@CPAN). Results showed that with the assistance of carboxyl groups, MnOx nanospheres (diameters 50–100 nm) could be distributed uniformly and stably on CPAN surface, and no obvious agglomeration was observed even when the amount of MnOx reached 23.4%. The resultant MnOx@CPAN showed efficient removal for organic pollutants including cationic dyes (e.g. methylene blue), phenol and antibiotic (e.g. ciprofloxacin). It was proposed that cationic dyes were removed through an adsorption-partial oxidation mechanism. The maximum adsorption capacity of methylene blue was 714 mg/g, substantially higher than the raw CPAN and most of previously reported adsorbents. Phenol was removed through a catalytic degradation process, with MnOx@CPAN as the catalyst and externally added peroxymonosulfate as the oxidant. Ciprofloxacin could be removed either through the adsorption process with CPAN as the adsorbent, or through the catalytic degradation process in the MnOx@CPAN/peroxymonosulfate system. We believe that the facile and green synthesis and excellent organic removal would make the as-synthesized MnOx@CPAN a promising candidate for organic pollutant removal. [ABSTRACT FROM AUTHOR]

Summary: Real‐time tracking of multiple particles is key for quantitative analysis of dynamic biophysical processes and materials science via time‐lapse microscopy image data, especially for single molecule biophysical techniques, such as magnetic tweezers and centrifugal force microscopy. However, real‐time multiple particle tracking with high resolution is limited by the current imaging processes or tracking algorithms. Here, we demonstrate 1 nm resolution in three dimensions in real‐time with a graphics‐processing unit (GPU) based on a compute unified device architecture (CUDA) parallel computing framework instead of only a central processing unit (CPU). We also explore the trade‐offs between processing speed and size of the utilized regions of interest and a maximum speedup of 137 is achieved with the GPU compared with the CPU. Moreover, we utilize this method with our recently self‐built centrifugal force microscope (CFM) in experiments that track multiple DNA‐tethered particles. Our approach paves the way for high‐throughput single molecule techniques with high resolution and efficiency. Lay Description: Particles are widely used as probes in life sciences through their motions. In single molecule techniques such as optical tweezers and magnetic tweezers, microbeads are used to study intermolecular or intramolecular interactions via beads tracking. Also tracking multiple beads' motions could study cell–cell or cell–ECM interactions in traction force microscopy. Therefore, particle tracking is of key important during these researches. However, parallel 3D multiple particle tracking in real‐time with high resolution is a challenge either due to the algorithm or the program. Here, we combine the performance of CPU and CUDA‐based GPU to make a hybrid implementation for particle tracking. In this way, a speedup of 137 is obtained compared the program before only with CPU without loss of accuracy. Moreover, we improve and build a new centrifugal force microscope for multiple single molecule force spectroscopy research in parallel. Then we employed our program into centrifugal force microscope for DNA stretching study. Our results not only demonstrate the application of this program in single molecule techniques, also indicate the capability of multiple single molecule study with centrifugal force microscopy. [ABSTRACT FROM AUTHOR]

Genetic engineering for heat stress tolerance can promote crop growth and improve yield. One wheat (Triticum aestivum L.) line Y16 (wild type) and two transgenic plants (Y16-3 and Y16-46) that express Hpa1, a functional fragment of harpin protein, were used in this study to investigate their possible abiotic stress tolerance under heat stress. Results showed that enhanced thermotolerance was observed in the Y16-3 and Y16-46 lines over the control wheat under stress conditions. However, this increased stress tolerance was significantly abolished by specific inhibitors such as fluridone or sodium tungstate (i.e., arrests abscisic acid (ABA) biosynthesis) and EGTA or La (i.e., arrests Ca signaling pathway) under heat exposure. By contrast, high activities of antioxidant enzymes such as superoxide dismutase, catalase, and ascorbate peroxidase (but not peroxidase) and low levels of oxidative damage (thiobarbituric acid reactive substance (TBARS) and chlorophyll) were detected in transgenic wheat lines compared with the control plant under stress exposure. However, this significant difference diminished after the addition of these specific inhibitors. Furthermore, a slight increase of HO was observed in the transgenic plant, instead of the control, without the addition of chemicals under heat stress. These results suggested that antioxidant enzymes, calcium, and ABA signaling pathways were involved in this Hpa1-mediated thermotolerance of transgenic wheat plants under stress exposure. Finally, a hypothetical model based on HO signaling was proposed to illustrate the possible mechanism of this enhanced heat stress tolerance. [ABSTRACT FROM AUTHOR]