Davidsencapps2701

At higher temperatures and longer annealing times, the bending was dominated by intensive bulk diffusion of Fe into the Au nanowhisker, accompanied by a significant migration of the Au-Fe interphase boundary toward the Fe layers. The irreversible bending was caused by the concentration dependence of the lattice parameter of the Au(Fe) alloy and by the volume effect associated with the interphase boundary migration. The results of this study demonstrate a high potential of chemical interdiffusion in the controlled plastic forming of ultrastrong metal nanostructures. By design of the thickness, microstructure, and composition of the coating as well as the parameters of heat treatment, bimetallic nanowhiskers can be bent in a controlled manner.The electrocatalytic reduction of CO2 (CO2ER) to liquid fuels is important for solving fossil fuel depletion. However, insufficient insight into the reaction mechanisms renders a lack of effective regulation of liquid product selectivity. Here, in situ surface-enhanced Raman spectroscopy (SERS) empowered by 13C/12C isotope exchange is applied to probing the CO2ER process on nanoporous silver (np-Ag). Direct spectroscopic evidence of the preliminary intermediates, *COOH and *OCO-, indicates that CO2 is coordinated to the catalyst via diverse adsorption modes. Further, the relative Raman intensities of the above intermediates vary notably on np-Ag modified by Cu or Pd, and the liquid product selectivity also changes accordingly. Combined with density functional theory calculations, this study demonstrates that the CO2 adsorption configuration is a critical factor governing the reaction selectivity. Meanwhile, *COOH and *OCO- are key targets in the initial stage regulating liquid product selectivity, which could facilitate future selective catalyst design.Liver injury can result in different hepatic diseases such as fatty liver, liver fibrosis, hepatitis, and liver failure, which are mainly responsible for global mortality and morbidity. Early diagnosis is critical for the treatment of liver diseases. Herein we report luminescence imaging of neutrophil-mediated acute liver injury, including alcoholic liver injury (ALI) and acute liver failure (ALF). To this purpose, a biodegradable luminescent material was developed by chemical functionalization of a cyclic oligosaccharide, which can be produced into nanoprobes (defined as LaCD NPs). Luminescence of LaCD NPs was dependent on the level of reactive oxygen species and myeloperoxidase (MPO). Correspondingly, activated neutrophils could be specifically imaged by LaCD NPs, and the luminescent signal was positively associated with the neutrophil count. In mouse models of ALI and ALF, LaCD NPs enabled precise quantification and tracking of neutrophils in livers. In both cases, changes in the luminescence intensity are consistent with time-dependent profiles of neutrophils, MPO, and other parameters relevant to the pathogenesis of liver injury. Moreover, the luminescence imaging capacity of LaCD NPs can be additionally improved by surface functionalization with a neutrophil-targeting peptide. In addition, preliminary in vitro and in vivo studies demonstrated good safety of LaCD NPs. Consequently, LaCD NPs can be further developed as an effective and biocompatible luminescent nanoprobe for in vivo dynamic detection of the development of neutrophil-mediated acute liver injury. It is also promising for diagnosis of other neutrophil-associated liver diseases.Extracellular vesicles (EVs) derived from mesenchymal stem cells (MSC-EVs) have been recognized as a promising cell-free therapy for acute kidney injury (AKI), which avoids safety concerns associated with direct cell engraftment. However, low stability and retention of MSC-EVs have limited their therapeutic efficacy. RGD (Arg-Gly-Asp) peptide binds strongly to integrins, which have been identified on the surface of MSC-EV membranes; yet RGD has not been applied to EV scaffolds to enhance and prolong bioavailability. Here, we developed RGD hydrogels, which we hypothesized could augment MSC-EV efficacy in the treatment of AKI models. learn more In vivo tracking of the labeled EVs revealed that RGD hydrogels increased retention and stability of EVs. Integrin gene knockdown experiments confirmed that EV-hydrogel interaction was mediated by RGD-integrin binding. Upon intrarenal injection into mouse AKI models, EV-RGD hydrogels provided superior rescuing effects to renal function, attenuated histopathological damage, decreased tubular injury, and promoted cell proliferation in early phases of AKI. RGD hydrogels also augmented antifibrotic effects of MSC-EVs in chronic stages. Further analysis revealed that the presence of microRNA let-7a-5p in MSC-EVs served as the mechanism contributing to the reduced cell apoptosis and elevated cell autophagy in AKI. In conclusion, RGD hydrogels facilitated MSC-derived let-7a-5p-containing EVs, improving reparative potential against AKI. This study developed an RGD scaffold to increase the EV integrin-mediated loading and in turn improved therapeutic efficacy in renal repair; therefore this strategy shed light on MSC-EV application as a cell-free treatment for potentiated efficiency.Benefiting from near-infrared persistent luminescence, chromium-doped zinc gallate nanoparticles have become appealing for background-free biomedical imaging applications, where autofluorescence from adjacent tissues no longer poses a problem. Nevertheless, the synthesis of persistent luminescent nanoparticles with controllable and biologically appropriate size, high luminescence intensity, and long persistent duration remains very challenging. Herein, we report a solvothermal synthetic route for preparing differently sized ZnGa2O4Cr nanoparticles with a particle size tunable from 4 to 31 nm and afterglow duration longer than 20 h. The route involves lower reaction temperatures and involves no reworking of the particles postsynthesis, providing materials that have far fewer unwanted defects and much higher luminescence yields (up to 51%). It was found that methanol played a paramount role in obtaining the Cr3+-doped ZnGa2O4 nanoparticles. The effects of methanol were discussed in combination with NMR spectroscopy studies and theoretical calculations, and the underlying alcohol-mediated growth and doping mechanisms were elucidated, which will be beneficial for developing highly persistent luminescent nanoparticles.