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Platinum (Pt)-based-nanomaterials are currently the most successful catalysts for the oxygen reduction reaction (ORR) in electrochemical energy conversion devices such as fuel cells and metal-air batteries. Nonetheless, Pt catalysts have serious drawbacks, including low abundance in nature, sluggish kinetics, and very high costs, which limit their practical applications. Herein, we report the first rationally designed nonprecious Co-Cu bimetallic metal-organic framework (MOF) using a low-temperature hydrothermal method that outperforms the electrocatalytic activity of Pt/C for ORR in alkaline environments. The MOF catalyst surpassed the ORR performance of Pt/C, exhibiting an onset potential of 1.06 V vs RHE, a half-wave potential of 0.95 V vs RHE, and a higher electrochemical stability (ΔE1/2 = 30 mV) after 1000 ORR cycles in 0.1 M NaOH. Additionally, it outperformed Pt/C in terms of power density and cyclability in zinc-air batteries. This outstanding behavior was attributed to the unique electronic synergy of the Co-Cu bimetallic centers in the MOF network, which was revealed by XPS and PDOS.Previously, we have demonstrated native mass spectrometry imaging (native MSI) in which the spatial distribution of proteins maintained in their native-like, folded conformations was determined using liquid extraction surface analysis (LESA). While providing an excellent testbed for proof of principle, the spatial resolution of LESA is currently limited for imaging primarily by the physical size of the sampling pipette tip. TGF-beta inhibitor Here, we report the adoption of nanospray-desorption electrospray ionization (nano-DESI) for native MSI, delivering substantial improvements in resolution versus native LESA MSI. In addition, native nano-DESI may be used for location-targeted top-down proteomics analysis directly from tissue. Proteins, including a homodimeric complex not previously detected by native MSI, were identified through a combination of collisional activation, high-resolution MS and proton transfer charge reduction.Monitoring of kanamycin residue has attracted considerable attention owing to the potential harm caused by the abuse of kanamycin. However, the detection of kanamycin has been limited owing to its electrochemical and optical inertness. Herein, we report a facile and highly efficient electrochemiluminescence (ECL) strategy for the detection of kanamycin based on the valence state effect of gold nanocluster (AuNC) probes. It is proven that Au0 in chemically reduced AuNCs (CR-AuNCs) could be oxidized to AuI via the redox reaction between kanamycin and CR-AuNCs in the presence of H2O2, resulting in ECL quenching due to the valence state change of CR-AuNCs. Because the ECL of the AuNC probes is sensitively affected by the valence state, excellent sensitivity for kanamycin was achieved without any signal amplification operation and aptamers. A preferable linear-dependent curve was acquired in the detection range from 1.0 × 10-11 to 3.3 × 10-5 M with an extremely low detection limit of 1.5 × 10-12 M. The proposed kanamycin sensing platform is very simple and shows high selectivity and an extremely broad linear range detection of kanamycin. Furthermore, the proposed sensing platform can detect kanamycin in milk samples with excellent recoveries. Therefore, this sensing strategy provides an effective and facile way to detect kanamycin and can help promote the understanding of the constructed mechanism of the AuNC-based ECL system, thus greatly broadening its potential application in ECL fields.Fine particulate matter (PM2.5) has been reported to be associated with neurological disorders. However, the effects of PM2.5 on changes in metabolic and lipid profile of the brain are unclear. In this study, global metabolomics and lipidomics in mice cortex were investigated from the analyses by ultraperformance liquid chromatography-Orbitrap mass spectrometry. The partial least-squares discriminant analysis showed that the metabolite and lipid profiles were significantly altered by PM2.5 exposure. The changed metabolic pathways including alanine, aspartate, and glutamate metabolism, carnitine metabolism, and glycerophospholipid remodeling pathway were found to be associated with a neurodegenerative process according to their corresponding molecular mechanisms. Our results indicated that PM2.5 exposure could induce neurological damage.The emerging donor-acceptor-donor (A-D-A)-type nonfullerene acceptors (NFAs) featuring near-infrared (NIR) photoresponsivity have greatly boosted the development of organic photovoltaics (OPVs) and display great potential for sensitive NIR organic photodetectors (OPDs). However, NIR NFAs with absorption above 1000 nm, which is of great importance for application in NIR OPDs for bioimaging, remote communication, night surveillance, etc., are still rare due to the scarcity of strong electron-rich cores. We report herein a new dithiophene building block, namely PDT, which exhibits the strongest electron-donating ability among the widely used dithiophene building blocks. By applying PDT and PDTT as the electron-donating cores and DFIC as the electron-accepting terminals, we developed two new NIR electron acceptors, PDTIC-4F and PDTTIC-4F, with optical absorptions up to 1030 nm, surpassing that of the well-known O6T-4F acceptor. In comparison with the carbon-oxygen-bridged core COi8 in O6T-4F, the synthetic complexity of PDT and PDTT is significantly reduced. Conventional OPV devices based on PM6PDTTIC-4F display power conversion efficiencies (PCEs) of up to 10.70% with a broad external quantum efficiency (EQE) response from the ultraviolet-visible to the infrared, leading to a high short-circuit current density (Jsc) of 25.90 mA cm-2. Encouraged by these results, we investigated inverted PM6PDTTIC-4F-based OPD devices by suppressing the dark current via modulation of the film thickness. The optimal OPD device exhibits compelling performance metrics that can compete with those of commercial silicon photodiodes a record responsivity of 0.55 A W-1 (900 nm) among photodiode-type OPDs and excellent shot-noise-limited specific detectivity (Dsh*) of over 1013 jones.