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The rapid development of electrochemical sensors holds great promise to serve as next generation point-of-care safety devices. However, the practical performances of electrochemical sensors are cruelly limited by stability, selectivity, and sensitivity. These issues have been well addressed by introducing rational designs into the modified electrode for achieving the required performances. Herein, we demonstrate the gadolinium oxide nanorods embedded on the graphene aerogel (GdO NRs/GA) for a highly selective electrochemical detection of carbendazim (CDM). The GdO NRs/GA nanocomposite was characterized using X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, field emission gun scanning electron microscopy, transmission electron microscopy with elemental mapping, and energy-dispersive spectrometry. The GdO NRs/GA-modified electrode shows a much improved electrochemical performance compared to other electrodes. Interestingly, the GdO NRs are strongly anchored in the GA matrix, which provides a more sufficient pathway for the rapid electron and ion transportation. On the basis of these findings, our proposed sensor achieves a wide detection range from 0.01 to 75 μM with a correlation coefficient of 0.996 and a low detection limit of 3.0 nM. Most markedly, the real-time monitoring of the proposed electrochemical sensor was proved by the successful determination of CDM in environmental samples. Our research work has opened a novel way to the rationale for the construction of highly efficient practical electrochemical sensors.Chemotherapy faces challenges, including poor aqueous solubility of the drugs, and cardiotoxicity. Micellar drug delivery systems (DDS) are used to encapsulate anticancer drugs for better therapeutic effects, however, with poor loading content. Herein, we synthesized a micellar DDS using γ-benzyloxy substituted poly(ε-caprolactone) as the hydrophobic block and coloaded anticancer doxorubicin (Dox) and antioxidant quercetin (Que). γ-Substituted oligo(ethylene) glycol (OEG) poly(ε-caprolactone)s were used as hydrophilic blocks to make the polymers thermoresponsive. Variation of the OEG chain allowed the tunability of the lower critical solution temperature. Moreover, drug loading and release were studied. Thermodynamic stability, size, and morphology were determined by fluorescence measurements, dynamic light scattering, and transmission electron microscopy. Combination loading demonstrated improved loading of Dox and Que. Biological studies were performed using HepG2 human liver cancer and H9c2 rat heart cells. learn more The use of biodegradable, biocompatible, and thermoresponsive polymers along with the coloading approach is a good strategy in developing DDSs.Shipboard measurements of offshore oil and gas facilities were conducted in the Gulf of Mexico in February 2018. Species measured at 1 s include methane, ethane, carbon-13 (13C) and deuterium (D) isotopes of methane, and several combustion tracers. Significant variability in the emission composition is observed between individual sites, with typical ethane/methane ratios around 5.3% and 13C and D methane isotopic compositions around -40 and -240‰, respectively. Offshore plumes were spatially narrower than expectations of the plume width based on terrestrial atmospheric stability classes; a modified Gaussian dispersion methodology using empirically measured horizontal plume widths was used to estimate the emission rates. A total of 103 sites were studied, including shallow and deepwater offshore platforms and drillships. Methane emission rates range from 0 to 190 kg/h with 95% confidence limits estimated at a factor of 10. The observed distribution is skewed with the top two emitters accounting for 20% of the total methane emissions of all sampled sites. Despite the greater throughput of the deepwater facilities, they had moderate emission rates compared to shallow-water sites. Analysis of background ethane enhancements also suggests a source region in shallow waters. A complete 1 s measurement database is published for use in future studies of offshore dispersion.The antiferromagnetic to ferromagnetic transition occurring above room temperature in FeRh is attracting interest for applications in spintronics, with perspectives for robust and untraceable data storage. Here, we show that FeRh films can be grown on a flexible metallic substrate (tape shaped), coated with a textured rock-salt MgO layer, suitable for large-scale applications. The FeRh tape displays a sharp antiferromagnetic to ferromagnetic transition at about 90 °C. Its magnetic properties are preserved by bending (radii of 300 mm), and their anisotropic magnetoresistance (up to 0.05%) is used to illustrate data writing/reading capability.Despite the great potential of combination therapy based on siRNA and chemotherapeutics, an efficient vehicle with abilities of well drug co-loading, synchronizing in vivo trafficking, and target-specific co-burst release remains elusive, which results in a suboptimal synergistic potency. Herein, a novel chitosan amphiphile (PEI-ss-HECS-ss-OA, HSPO) with glutathione (GSH)-reversible cationization and hydrophobicization by polyethylenimine (PEI) and octylamine (OA), respectively, was developed for this purpose. HSPO spontaneously assembled in aqueous solution to be a micellar system and effectively co-encapsulated the two drugs with an adjustable dosage ratio. With a surface charge inversion strategy by hyaluronic acid (HA) coating, the HA(HSPO) co-delivery micelles with a negative surface charge (-21.45 ± 1.44 mV) and suitable size (192.52 ± 7.41 nm) selectively accumulated into CD44 overexpressed A549 tumors through a combination of passive and active targeting mechanism. Then, tumor cytoplasm-selective co-burst release was obtained through GSH triggered collapse of the amphiphilic assembly alongside a decrease of positive charge condensation, finally leading to an enhanced synergistic antitumor effect with a superior inhibition ratio of 86.63%. Overall, this study validated the great promise of HSPO as an efficient site-specific rapid co-trafficking vehicle of siRNA and chemotherapeutics for a remarkable synergistic tumor inhibition.Heavy metal pollution is a severe problem worldwide. Great efforts have been devoted in developing effective and eco-friendly ways to remove heavy metal ions from contaminated water. However, challenges remain in terms of the high cost, the complex preparation processes required, low efficiency, and difficulties in scaling-up. Here, we report a sulfhydryl-functionalized wood (SH-wood) membrane featuring three-dimensional mesoporous and low-tortuosity lumens, which serve as multisite metal traps to achieve highly efficient heavy metal ion removal from wastewater. Benefiting from the unique microstructure of wood, the resulting membrane exhibits a high saturation uptake capacity of 169.5, 384.1, 593.9, and 710.0 mg·g-1 for Cu2+, Pb2+, Cd2+, and Hg2+ ions, respectively. Meanwhile, the SH-wood membrane can be easily regenerated at least eight times without apparent performance loss. Furthermore, stacking multilayers of the SH-wood filter is designed. Because of its high yet universal heavy metal ion absorbance capability, the multilayer SH-wood filter can effectively remove diverse heavy metal ions from real contaminated water, meeting the WHO standards while also displaying a high flux rate of 1.3 × 103 L·m-2·h-1. Our work presents a promising strategy for the scalable and highly efficient removal of heavy metal ions from sewage for environmental remediation.Tetrahydrobiopterin-dependent hydroxylation of aromatic amino acids is the first step in the biosynthesis of many neuroactive compounds in humans. A fundamental challenge in building these pathways in Escherichia coli is the provision of the non-native hydroxylase cofactor, tetrahydrobiopterin. To solve this, we designed a genetic selection that relies on the tyrosine synthesis activity of phenylalanine hydroxylase. Using adaptive laboratory evolution, we demonstrate the use of this selection to discover (1) a minimum set of heterologous enzymes and a host folE (T198I) mutation for achieving this type of hydroxylation chemistry in whole cells, (2) functional complementation of tetrahydrobiopterin by indigenous cofactors, and (3) a tryptophan hydroxylase mutation for improving protein abundance. Thus, the goal of having functional aromatic-amino-acid hydroxylation in E. coli was achieved through directed metabolic pathway evolution.Solid oxide fuel cells (SOFCs) can directly operate on hydrocarbon fuels such as natural gas; however, the widely used nickel-based anodes face grand challenges such as coking, sulfur poisoning, and redox instability. We report a novel double perovskite oxide Sr2Co0.4Fe1.2Mo0.4O6-δ (SCFM) that possesses excellent redox reversibility and can be used as both the cathode and the anode. When heat-treated at 900 °C in a reducing environment, double perovskite phase SCFM transforms into a composite of the Ruddlesden-Popper structured oxide Sr3Co0.1Fe1.3Mo0.6O7-δ (RP-SCFM) with the Co-Fe alloy nanoparticles homogeneously distributed on the surface of RP-SCFM. At 900 °C in an oxidizing atmosphere, the composite transforms back into the double perovskite phase SCFM. The excellent oxygen reduction reaction catalytic activity and mixed ionic-electronic conductivity make SCFM an excellent cathode material for SOFCs. When SCFM is used as the anode, excellent performance and stability are achieved upon either direct oxidation of methane as a fuel or operation with sulfur-containing fuels. The excellent redox reversibility coupled with outstanding electrical and catalytic properties manifested by SCFM will enable a broad application in energy conversion applications.Wearable and stretchable electronics including various conductors and sensors are featured with their lightweight, high flexibility, and easy integration into functional devices or textiles. However, most flexible electronic materials are still unsatisfactory due to their poor recoverability under large strain. Herein, we fabricated a carbon nanotubes (CNTs) and polyurethane (PU) nanofibers composite helical yarn with electrical conductivity, ultrastretchability, and high stretch sensitivity. The synergy of elastic PU molecules and spring-like microgeometry enable the helical yarn excellent stretchability, while CNTs are stably winding-locked into the yarn through a simple twisting strategy, making good conductivity. By virtue of the interlaced conductive network of CNTs in microlevel and the helical structure in macrolevel, the CNTs/PU helical yarn achieves good recoverability within 900% and maximum tensile elongation up to 1700%. With these features, it can be used as a superelastic and highly stable conductive wire. link2 Moreover, it also can monitor the human motion as a rapid-response strain sensor by adjusting the content of the CNTs simply. This general and low-cost strategy is of great promise for ultrastretchable wearable electronics and multifunctional devices.An Nb-doped TiO2 (Nb-TiO2) film comprising a double structure stacked with a bottom compact layer and top mesoporous layers was synthesized by treating a Ti precursor-coated substrate using a one-step low-temperature steam-annealing (SA) method. The SA-based Nb-TiO2 films possess high crystallinity and conductivity, and that allows better control over the conduction band (CB) of TiO2 for the electron transport layer (ETL) of the perovskite solar cells by the Nb doping level. Optimization of power conversion efficiency (PCE) for the Nb-TiO2-based ETL was combined with the CB level tuning of the mixed-halide perovskite by changing the Br/I ratio. link3 This band offset management enabled to establish the most suitable energy levels between the ETL and the perovskites. This method was applied to reduce the band gap of perovskites to enhance the photocurrent density while maintaining a high open-circuit voltage. As a result, the optimal combination of 5 mol % Nb-TiO2 ETL and 10 mol % Br in the mixed-halide perovskite exhibited high photovoltaic performance for low-temperature device fabrication, achieving a high-yield PCE of 21.