Cobalt–nitrogen–carbon is hitherto considered as one of the most satisfactory alternatives to precious metal catalysts for oxygen electrocatalysts. However, precisely tuning the local coordination of ...Co sites and thus engineering d‐orbital electron configuration to optimize the binding energy of the intermediates remains a huge challenge. Herein, a robust electrostatic self‐assembly strategy is developed to engineer penta‐coordinated Co sites by introducing axial O ligands with atomic‐level precision to form CoN4O1 configurations on MXene nanosheets (CoN4‐O/MX). The optimized CoN4‐O/MX demonstrates outstanding bifunctional electrocatalytic performance with a small potential gap of 0.72 V, significantly outperforming the cobalt–nitrogen–carbon catalyst with plane‐symmetric CoN4 sites and precious metal counterparts. The Zn–air batteries integrated with CoN4‐O/MX provide an outstanding peak power density of 182.8 mW cm−2 and a long‐term cyclability for 250 h. Density functional theory calculations reveal that CoO coordination induces electronic delocalization to draw off partial electrons from the dz2 orbital, which forms unsaturated orbital filling and lifts the energy level, resulting in a stronger Lewis basicity to facilitate electron injection into the intermediate. The study presented here provides not only a novel methodology to achieve precise control of heteroatom coordination, but also a fundamental understanding about the structure–activity relationships of dz2 orbitals.
A robust electrostatic self‐assembly strategy is developed to engineer penta‐coordinated Co sites by introducing axial O ligands with atomic‐level precision to form CoN4O1 configurations. CoO coordination induces electronic delocalization to regulate Co 3d orbitals energy level and dz2 orbital occupancy, resulting in improved OH* intermediate activation abilities and outstanding ORR performance compared to cobalt–nitrogen–carbon with symmetric Co‐N4 sites.
Atomically dispersed metal‐nitrogen‐carbon (M‐N‐C) catalysts have exhibited encouraging oxygen reduction reaction (ORR) activity. Nevertheless, the insufficient long‐term stability remains a ...widespread concern owing to the inevitable 2‐electron byproducts, H2O2. Here, we construct Co‐N‐Cr cross‐interfacial electron bridges (CIEBs) via the interfacial electronic coupling between Cr2O3 and Co‐N‐C, breaking the activity‐stability trade‐off. The partially occupied Cr 3d‐orbitals of Co‐N‐Cr CIEBs induce the electron rearrangement of CoN4 sites, lowering the Co‐OOH* antibonding orbital occupancy and accelerating the adsorption of intermediates. Consequently, the Co‐N‐Cr CIEBs suppress the two‐electron ORR process and approach the apex of Sabatier volcano plot for four‐electron pathway simultaneously. As a proof‐of‐concept, the Co‐N‐Cr CIEBs is synthesized by the molten salt template method, exhibiting dominant 4‐electron selectively and extremely low H2O2 yield confirmed by Damjanovic kinetic analysis. The Co‐N‐Cr CIEBs demonstrates impressive bifunctional oxygen catalytic activity (▵E=0.70 V) and breakthrough durability including 100 % current retention after 10 h continuous operation and cycling performance over 1500 h for Zn‐air battery. The hybrid interfacial configuration and the understanding of the electronic coupling mechanism reported here could shed new light on the design of superdurable M‐N‐C catalysts.
A cross‐interfacial electronic bridges (CIEBs) is constructed via interfacial electronic coupling between Cr2O3 and Co‐N‐C, breaking the trade‐off between activity and stability. The partially occupied Cr 3d‐orbitals of Co‐N‐Cr CIEBs induce the electron rearrangement of CoN4 sites, lowering the Co‐OOH* antibonding orbital occupancy and accelerating the adsorption of intermediates. Consequently, the Co‐N‐Cr CIEBs suppress the two‐electron ORR process and approach the apex of Sabatier volcano plot for four‐electron pathway simultaneously.
•Profiling both protein and miRNA affords a better prognostic capacity.•Testing both proteins and miRNA expression in EVs can increase benefit.•Differential miRNA and protein expression have no ...correlation with age and sex.
Protein and miRNA enrichment within extracellular vesicles (EVs) isolated from patients with Alzheimer’s disease (AD) has been shown to have putative diagnostic value. However, whether a combination of both will be more advantageous is unknown. EVs were enriched from serum samples obtained from patients with sporadic AD (n = 13), mild cognitive impairment (MCI) (n = 10), vascular dementia (VaD) (n = 10), and healthy controls (HC) (n = 10). Expression of protein levels of beta-amyloid peptide (Aβ1–42), total tau, P-T181-tau, and P-S396-tau and 18 microRNAs (miRNAs) in the EVs was performed by ELISA and qRT-PCR, respectively. Results were validated in an independent cohort of 18 subjects each by qRT-PCR assays. EV protein expression of Aβ1–42, total-tau, P-T181-tau and P-S396-tau, were significantly different among AD, MCI and VaD. Hsa-miR-1306-5p, hsa-miR-342-3p, and hsa-15b-3p were all significantly downregulated in patients with AD compared to HC (P < 0.05), only hsa-miR-1306-5p expression was differentially expressed between AD, MCI, and VaD samples. Similarly, whereas all 14 miRNAs were significantly upregulated in patients with AD compared to HC, only hsa-miR-93-5p, hsa-miR-424-5p, and hsa-miR-3065-5p were differentially expressed when AD samples were compared to MCI and VaD samples. Even though the sample size was small, the results of the current pilot study indicates that hsa-miR-1306-5p, hsa-miR-93-5p, hsa-miR-424-5p, and hsa-miR-3065-5p, and expression of P-S396-tau in EVs might provide a combinatorial protein and miRNA signature to differentiate between HC, patients with MCI or VaD from patient with sporadic AD.
Hepatitis B virus (HBV) infection is a serious global health problem. After the viruses infect the human body, the host can respond to the virus infection by coordinating various cellular responses, ...in which mitochondria play an important role. Evidence has shown that mitochondrial proteins are involved in host antiviral responses. In this study, we found that the overexpression of TIM22 and TIM29, the members of the inner membrane translocase TIM22 complex, significantly reduced the level of intracellular HBV DNA and RNA and secreted HBV surface antigens and E antigen. The effects of TIM22 and TIM29 on HBV replication and transcription is attributed to the reduction of core promoter activity mediated by the increased expression of SRSF1 which acts as a suppressor of HBV replication. This study provides new evidence for the critical role of mitochondria in the resistance of HBV infection and new targets for the development of treatment against HBV infection.
The endometrium plays a critical role in embryo implantation and pregnancy, and a thin uterus is recognized as a key factor in embryo implantation failure. Umbilical cord mesenchymal stem cells ...(UC-MSCs) have attracted interest for the repair of intrauterine adhesions. The current study investigated the repair of thin endometrium in rats using the UC-MSCs and the mechanisms involved. Rats were injected with 95% ethanol to establish a model of thin endometrium. The rats were randomly divided into normal, sham, model, and UC-MSCs groups. Endometrial morphological alterations were observed by hematoxylin-eosin staining and Masson staining, and functional restoration was assessed by testing embryo implantation. The interaction between UC-MSCs and rat endometrial stromal cells (ESCs) was evaluated using a transwell 3D model and immunocytochemistry. Microarray mRNA and miRNA platforms were used for miRNA-mRNA expression profiling. Gene ontology (GO) and Kyoto encyclopedia of genes and genomes (KEGG) analyses were performed to identify the biological processes, molecular functions, cellular components, and pathways of endometrial injury and UC-MSCs transplantation repair and real-time quantitative reverse transcription PCR (qRT-PCR) was performed to further identify the expression changes of key molecules in the pathways. Endometrium thickness, number of glands, and the embryo implantation numbers were improved, and the degree of fibrosis was significantly alleviated by UC-MSCs treatment in the rat model of thin endometrium. In vitro cell experiments showed that UC-MSCs migrated to injured ESCs and enhanced their proliferation. miRNA microarray chip results showed that expression of 45 miRNAs was downregulated in the injured endometrium and upregulated after UC-MSCs transplantation. Likewise, expression of 39 miRNAs was upregulated in the injured endometrium and downregulated after UC-MSCs transplantation. The miRNA-mRNA interactions showed the changes in the miRNA and mRNA network during the processes of endometrial injury and repair. GO and KEGG analyses showed that the process of endometrial injury was mainly attributed to the decomposition of the extracellular matrix (ECM), protein degradation and absorption, and accompanying inflammation. The process of UC-MSCs transplantation and repair were accompanied by the reconstruction of the ECM, regulation of chemokines and inflammation, and cell proliferation and apoptosis. The key molecules involved in ECM-receptor interaction pathways were further verified by qRT-PCR. Itga1 and Thbs expression decreased in the model group and increased by UC-MSCs transplantation, while Laminin and Collagen expression increased in both the model group and MSCs group, with greater expression observed in the latter. This study showed that UC-MSCs transplantation could promote recovery of thin endometrial morphology and function. Furthermore, it revealed the expression changes of miRNA and mRNA after endometrial injury and UC-MSCs transplantation repair processed, and signaling pathways that may be involved in endometrial injury and repair.
Influenza vaccines for H7N9 subtype have shown low immunogenicity in human clinical trials. Using novel adjuvants might represent the optimal available option in vaccine development. In this study, ...we demonstrated that the using of the STING agonist cGAMP as a mucosal adjuvant is effective in enhancing humoral, cellular and mucosal immune responses of whole virus, inactivated H7N9 vaccine in mice. A single dose of immunization was able to completely protect mice against a high lethal doses of homologous virus challenge with an significant dose-sparing effect. We also found that intranasal co-administration of H7N9 vaccine with cGAMP could provide effective cross protection against H1N1, H3N2, and H9N2 influenza virus. Furthermore, cGAMP induced significantly higher nucleoprotein specific CD4
and CD8
T cells responses in immunized mice, as well as upregulated the IFN-γ and Granzyme B expression in the lung tissue of mice in the early stages post a heterosubtypic virus challenge. These results indicated that STING agonist cGAMP was expected to be an effective mucosal immune adjuvant for pre-pandemic vaccines such as H7N9 vaccines, and the cGAMP combined nasal inactivated influenza vaccine will also be a promising strategy for development of broad-spectrum influenza vaccines.
We present Interactive Gibson Benchmark, the first comprehensive benchmark for training and evaluating Interactive Navigation solutions. Interactive Navigation tasks are robot navigation problems ...where physical interaction with objects (e.g., pushing) is allowed and even encouraged to reach the goal. Our benchmark comprises two novel elements: 1) a new experimental simulated environment, the Interactive Gibson Environment, that generate photo-realistic images of indoor scenes and simulates realistic physical interactions of robots and common objects found in these scenes; 2) the Interactive Navigation Score, a novel metric to study the interplay between navigation and physical interaction of Interactive Navigation solutions. We present and evaluate multiple learning-based baselines in Interactive Gibson Benchmark, and provide insights into regimes of navigation with different trade-offs between navigation, path efficiency and disturbance of surrounding objects. We make our benchmark publicly available1 and encourage researchers from related robotics disciplines (e.g., planning, learning, control) to propose, evaluate, and compare their Interactive Navigation solutions in Interactive Gibson Benchmark.
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