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Electrochemically grafted 4-ABA not only leads to a favorable orientation of BOD as validated by fitting a kinetic model to the electrocatalytic data, but also acts to alleviate RGO aggregation as disclosed by scanning electron microscopy, most likely due to the electrostatic repulsion between 4-ABA-grafted graphene layers. With a half-lifetime of 55 h, the bioelectrode also shows the highest operational stability for DET-type MvBOD-based bioelectrodes reported to date. The bioelectrode was finally shown to work well as a biocathode of a membrane-less glucose/O2 enzymatic biofuel cell with a maximum power density of 22 μW cm-2 and an open circuit voltage of 0.51 V.Cardiac conduction is an important function of the heart. Selleckchem Vismodegib To date, accurate measurement of conduction velocity (CV) in vitro is hindered by the low spatial resolution and poor signal-to-noise ratio of microelectrode arrays (MEAs), or the cytotoxicity and end-point analysis of fluorescence optical imaging. Here, we have developed a new label-free method based on defocused brightfield imaging to quantify CV by analyzing centroid displacements and contraction trajectories of each cardiomyocyte in a monolayer of human stem cell-derived cardiomyocytes (iPSC-CMs). Our data revealed that the time delay between intracellular calcium release and the initiation of cell contraction is highly consistent across cardiomyocytes; however, the duration a cell takes to reach its maximum beating magnitude varies significantly, proving that the time delay in excitation-contraction coupling is largely constant in iPSC-CMs. Standard calcium imaging of the same iPSC-CM populations (~106 cells) was conducted for comparison with our label-free method. The results confirmed that our label-free method was capable of achieving highly accurate CV mapping (17.64 ± 0.89 cm/s vs. 17.95 ± 2.29 cm/s, p-value>0.1). Additionally, our method effectively revealed various shapes in cell beating pattern. We also performed label-free CV mapping on disease-specific iPSC-CM monolayers with plakophilin-2 (PKP2) knockdown, which effectively quantified their low CV values and further validated the arrhythmogenic role of PKP2 mutation in arrhythmogenic right ventricular cardiomyopathy (ARVC) through the disruption of cardiac conduction. The label-free method offers a cytotoxic-free technique for long-term measurement of dynamic beating trajectories, beating propagation and conduction velocities of cardiomyocyte monolayers.Phytoextraction using Celosia argentea Linn. can potentially decontaminate Cd-contaminated soils. However, most earlier studies have been conducted at laboratory scale and for a relatively short remediation period. To evaluate the phytoextraction efficiency of C. argentea combined with different soil amendments (ammonium chloride, Bacillus megaterium, and citric acid), an 18-month field experiment was carried out in a farmland soil contaminated with 3.68 mg kg-1 Cd by mine tailings in southern China. Soil Cd concentrations were decreased by 6.34 ± 0.73% after the three harvestings (with no amendments), which was 2.27 times that of the no-planting control (p less then 0.05). Application of ammonium chloride, B. megaterium, and citric acid increased the overall Cd reduction rate in soil by 40.5%, 46.1%, and 105%, respectively. The application of citric acid decreased total Cd in soil by up to 16.9% in the rhizosphere soil and 13.0% in the bulk soil. The highest annual shoot biomass yield and Cd extraction amount reached 8.79 t ha-1 and 273 g ha-1. Acid-soluble Cd fraction in the rhizosphere was significantly lower compared to that in the bulk soil (p less then 0.05), which indicates that mobile Cd in the rhizosphere was taken up by the roots vastly. C. argentea phytoextraction also improved soil metabolic functions by increasing the activities of soil enzymes (urease, invertase, phosphatase, and catalase). These findings demonstrate that Cd phytoextraction using C. argentea with the application of soil amendments can greatly improve the quality of Cd-contaminated soils.Contamination by polycyclic aromatic hydrocarbons (PAHs) has been observed at high elevation environments; however, the occurrence and spatial variation of PAHs in alpine lakes of China is not well understood. We measured 15 priority PAHs in the sediments of Lake Qinghai in the Qinghai-Tibet Plateau, and assessed their distribution, source, and ecological risks. The total PAH concentration ranged from 30.4 to 125.2 ng g-1. Low molecular weight PAHs were dominant in the sediments, suggesting a local source for the emissions. Sediment sites closer to local settlements and rivers had higher concentration of PAHs. The concentration of PAHs was significantly correlated with pH, probably as a result of the high salinity of the lake, while it was not significantly correlated with organic matter content. Molecular diagnostic ratio analysis indicated that PAHs were derived mainly from coal and biomass combustion. Specifically, the positive matrix factorization model showed that petrogenic sources, vehicular emissions, biomass combustion, and coal combustion contributed for 11.6, 16.3, 23.6, and 48.5% of the PAHs, respectively. The risk quotient method was used to assess ecological risk of PAHs individually. The results indicate that indeno[1,2,3-cd]pyrene, benzo[b]fluoranthene, benzo[a]pyrene, phenanthrene, and anthracene would produce moderate ecological risks in 5, 20, 65, 100, and 100% of the sediment sites, respectively, while the other 10 PAH homologues would scarcely produce any serious ecological risk. We used the hierarchical Archimedean copula integral assessment model to evaluate the integral risk of PAHs. The result showed that 10, 40, and 50% of the sediment sites belong to mid-high, low, and mid-low risk levels, respectively. The current concentration and risk levels of PAHs in this study might be used as a baseline to assess the influence of future anthropogenic activities.Glandless cotton can be grown to obtain cotton seeds free of toxic gossypol for use as both food and feed. However, they are not grown normally due to their lesser productivity and higher susceptibility to biotic stress. Great attention has been paid to biotic stresses rather than abiotic stresses on glandless cotton. Chromium (Cr) is a common pollutant of soil and considered a serious threat to plants due to its adverse effects on different functions. Although numerous studies are available on the toxicity of Cr6+ in various plants. However, its adverse effects and mechanism of toxicity in glandless cotton can seldom be found in the literature. This study examined the Cr6+ effect on glandless cotton in comparison to glanded cotton. Four pairs of glanded and glandless cotton near-isogenic lines (NILs) were exposed to different doses (0, 10, 50, and 100 μM/L) of Cr6+ for seven days, and biochemical, physiological, molecular, and ultrastructure changes were observed, which were significantly affected by Cr6+ at high concentrations in all NILs.