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The rational construction of highly efficient electrocatalysts for the oxygen evolution reaction (OER) plays a critical role in energy conversion systems. Designing heterostructures is a common and effective strategy to improve the performance of electrocatalysts. In this paper, an MnS2/Co4S3/Ni3S2 heterostructure was synthesized on Ni foam using a one-step vulcanization method. It provides a modified electronic structure and plentiful three-phase heterogeneous interfaces that can effectively enrich the active sites and accelerate electron transfer, thereby improving the OER activity. Thanks to the heterostructure, the MnS2/Co4S3/Ni3S2 exhibits a low overpotential of 265 and 304 mV for the OER to reach current densities of 50 and 100 mA/cm2, respectively. Furthermore, the surface reconstruction of MnS2/Co4S3/Ni3S2 has been investigated, which revealed the formation of metal hydr(oxy)oxides evolved during the OER process. This work provides a facile strategy for constructing three-phase heterostructures, shedding light on the development of high-performance, nonprecious metal-based OER electrocatalysts.
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Rational design and controllable synthesis of metal-organic frameworks nanosheets is critical for electrochemical catalysis. Herein, a carnation-like ZIF-9 nanostructure made of nanosheets is grown on nickel foam (ZIF-9/NF) by a simple one-step solvothermal method, the morphology evolution and the electrocatalytic oxygen evolution properties have been investigated by controlling the solvothermal time. The binder-free ZIF-9-d/NF (60 h, solvothermal time is 60 h) electrode delivers efficient electrocatalytic oxygen evolution reaction activity with low overpotentials of 312 and 337 mV at 50 and 100 mA cm-2, respectively. Furthermore, ZIF-9-d/NF (60 h) exhibits excellent stability without obvious attenuation for at least 30 h at 200 mA cm-2. The excellent performances can be attributed to the combination of the highly exposed active sites in the ZIF-9-d nanosheets, as well as the effective electron conduction and mass transfer. This work provides much possibilities for ZIF-9 nanosheets as binder-free electrode for electrocatalyst.
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BACKGROUND: Classical swine fever (CSF) is a severe disease of pigs that results in huge economic losses worldwide and is caused by classical swine fever virus (CSFV). CSFV nonstructural protein 4 A (NS4A) plays a crucial role in infectious CSFV particle formation. However, the function of NS4A during CSFV infection is not well understood. RESULTS: In this study, we used RNA-seq to investigate the functional role of CSFV NS4A in PK-15 cells. A total of 3893 differentially expressed genes (DEGs) were identified in PK-15 cells expressing NS4A compared to cells expressing the empty vector (NC). Twelve DEGs were selected and further verified by RTâqPCR. GO and KEGG enrichment analyses revealed that these DEGs were associated with multiple biological functions, including cell adhesion, apoptosis, host defence response, the inflammatory response, the immune response, and autophagy. Interestingly, some genes associated with host immune defence and inflammatory response were downregulated, and some genes associated with host apoptosis and autophagy were upregulated. CONCLUSION: CSFV NS4A inhibits the innate immune response, and suppresses the expression of important genes associated with defence response to viruses and inflammatory response, and regulates cell adhesion, apoptosis and autophagy.
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Vírus da Febre Suína Clássica , Peste Suína Clássica , Doenças dos Suínos , Suínos , Animais , Vírus da Febre Suína Clássica/genética , Replicação Viral/fisiologia , Linhagem Celular , Perfilação da Expressão Gênica/veterináriaRESUMO
Self-assembly of site-selective protein-polymer conjugates into stimuli-responsive micelles is interesting owing to their potential biomedical applications, ranging from molecular imaging to drug delivery, but remains a significant challenge. Herein we report a method of site-selective in situ growth-induced self-assembly (SIGS) to synthesize site-specific human serum albumin-poly(2-(diisopropylamino)ethyl methacrylate) (HSA-PDPA) conjugates that can in situ self-assemble into pH-responsive micelles with tunable morphologies. Indocyanine green (ICG) was selectively loaded into the core of sphere-like HSA-PDPA micelles to form pH-responsive fluorescence nanoprobes. The nanoprobes rapidly dissociated into protonated individual unimers at a transition pH of around 6.5, that is the extracellular pH of tumors, which resulted in a sharp fluorescence increase and markedly enhanced cellular uptake. In a tumor-bearing mouse model, they exhibited greatly enhanced tumor fluorescence imaging as compared to ICG alone and pH-nonresponsive nanoprobes. These findings suggest that pH-responsive and site-selective protein-polymer conjugate micelles synthesized by SIGS are promising as a new class of tumor microenvironment-responsive nanocarriers for enhanced tumor imaging and therapy.
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Fluorescência , Melanoma/patologia , Metilmetacrilatos/química , Imagem Molecular/métodos , Polímeros/química , Albumina Sérica Humana/química , Microambiente Tumoral , Animais , Feminino , Humanos , Concentração de Íons de Hidrogênio , Processamento de Imagem Assistida por Computador , Verde de Indocianina , Melanoma/diagnóstico por imagem , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Micelas , Espectroscopia de Luz Próxima ao Infravermelho , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The 5G network is anticipated to meet the challenging requirements of mobile traffic in the 2020s, which are characterized by super high data rate, low latency, high mobility, high energy efficiency and high traffic density. This paper provides an overview of China Mobile's 5G vision and potential solutions. Three key characteristics of 5G are analysed, i.e. super fast, soft and green. The main 5G R&D themes are further elaborated, which include five fundamental rethinkings of the traditional design methodologies. The 5G network design considerations are also discussed, with cloud radio access network, ultra-dense network, software defined network and network function virtualization examined as key potential solutions towards a green and soft 5G network. The paradigm shift to user-centric network operation from the traditional cell-centric operation is also investigated, where the decoupled downlink and uplink, control and data, and adaptive multiple connections provide sufficient means to achieve a user-centric 5G network with 'no more cells'. The software defined air interface is investigated under a uniform framework and can adaptively adapt the parameters to well satisfy various requirements in different 5G scenarios.
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A single chain polypeptide containing the low density lipoprotein receptor (LDLR) ligand Seq-1 with blood-brain barrier (BBB) crossing activity has been successfully modified by conventional genetic engineering to self-assemble into stable protein-only nanoparticles of 30nm. The nanoparticulate presentation dramatically enhances in vitro, LDLR-dependent cell penetrability compared to the parental monomeric version, but the assembled protein does not show any enhanced brain targeting upon systemic administration. While the presentation of protein drugs in form of nanoparticles is in general advantageous regarding correct biodistribution, this principle might not apply to brain targeting that is hampered by particular bio-physical barriers. Irrespective of this fact, which is highly relevant to the nanomedicine of central nervous system, engineering the cationic character of defined protein stretches is revealed here as a promising and generic approach to promote the controlled oligomerization of biologically active protein species as still functional, regular nanoparticles.
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Barreira Hematoencefálica , Sistemas de Liberação de Medicamentos , Nanopartículas , Peptídeos , Humanos , Receptores de LDL , Distribuição TecidualRESUMO
This study investigates the correlation between dietary sialic acid intake which mainly come from eggs, red meat, and dairy products and serum HbA1c levels. A survey among Xiamen's general population, China, collected dietary data from 2,908 participants over the past year. A semi-quantitative food frequency questionnaire (FFQ) was employed. Sialic acid intake was calculated, along with measurements of biochemical indicators, including fasting blood glucose, HbA1c, blood lipids, and insulin. Sociodemographic and physical data were also collected. Logistic regression models evaluated the relationship between dietary sialic acid and HbA1c levels. The daily sialic acid intake in Xiamen's general population was 48.55 (21.68, 65.23) mg/1000Kcal, accompanied by a 1.96% rate of high HbA1c. A significant negative correlation between dietary sialic acid and HbA1c was observed. Individuals in the highest quartile of sialic acid intake (> 65.48 mg/1000 kcal) had a lower risk of high HbA1c compared to those in the lowest quartile (< 23.63 mg/1000 kcal) [OR: 0.123 (0.022, 0.689)]. A high dietary sialic acid intake within a specific range may reduce the risk of elevated HbA1c levels, suggesting a potential preventive effect. Note that this effect is limited to specific intake ranges.
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Dieta , Hemoglobinas Glicadas , Ácido N-Acetilneuramínico , Humanos , Ácido N-Acetilneuramínico/sangue , Hemoglobinas Glicadas/análise , Hemoglobinas Glicadas/metabolismo , China , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Glicemia/metabolismo , Glicemia/análise , IdosoRESUMO
Objective: The objective of this study was to utilize LASSO regression (Least Absolute Shrinkage and Selection Operator Regression) to identify key variables in septic patients and develop a predictive model for intensive care unit (ICU) mortality. Methods: We conducted a cohort consisting of septic patients admitted to the ICU between December 2016 and July 2019. The disease severity and laboratory index were analyzed using LASSO regression. The selected variables were then used to develop a model for predicting ICU mortality. AUCs of ROCs were applied to assess the prediction model, and the accuracy, sensitivity and specificity were calculated. Calibration were also used to assess the actual and predicted values of the predictive model. Results: A total of 1733 septic patients were included, among of whom 382 (22%) died during ICU stay. Ten variables, namely mechanical ventilation (MV) requirement, hemofiltration (HF) requirement, norepinephrine (NE) requirement, septicemia, multiple drug-resistance infection (MDR), thrombocytopenia, hematocrit, red-cell deviation width coefficient of variation (RDW-CV), C-reactive protein (CRP), and antithrombin (AT) III, showed the strongest association with sepsis-related mortality according to LASSO regression. When these variables were combined into a predictive model, the area under the curve (AUC) was found to be 0.801. The AUC of the validation group was 0.791. The specificity of the model was as high as 0.953. Within the probability range of 0.25 to 0.90, the predictive performance of the model surpassed that of individual predictors within the cohort. Conclusion: Our findings suggest that a predictive model incorporating the variables of MV requirement, HF requirement, NE requirement, septicemia, MDR, thrombocytopenia, HCT, RDW-CV, CRP, and AT III exhibiting an 80% likelihood of predicting ICU mortality in sepsis and demonstrates high accuracy.
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The efficiency of photocatalytic hydrogen evolution is currently limited by poor light adsorption, rapid recombination of photogenerated carriers, and ineffective surface reaction rate. Although heterojunctions with innovative morphologies and structures can strengthen built-in electric fields and maximize the separation of photogenerated charges. However, how to rational design of novel multidimensional structures to simultaneously improve the above three bottleneck problems is still a research imperative. Herein, a unique Cu2OâS@graphene oxide (GO)@Zn0.67Cd0.33S Three dimensional (3D) hollow heterostructure is designed and synthesized, which greatly extends the carrier lifetime and effectively promotes the separation of photogenerated charges. The H2 production rate reached 48.5 mmol g-1 h-1 under visible light after loading Ni2+ on the heterojunction surface, which is 97 times higher than that of pure Zn0.67Cd0.33S nanospheres. Furthermore, the H2 production rate can reach 77.3 mmol g-1 h-1 without cooling, verifying the effectiveness of the photothermal effect. Meanwhile, in situ characterization and density flooding theory calculations reveal the efficient charge transfer at the p-n 3D hollow heterojunction interface. This study not only reveals the detailed mechanism of photocatalytic hydrogen evolution in depth but also rationalizes the construction of superior 3D hollow heterojunctions, thus providing a universal strategy for the materials-by-design of high-performance heterojunctions.
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Transition bimetallic sulphides have emerged as important electrode materials for supercapacitors owing to their low toxicity, environmental friendliness, cost-effectiveness, multiple oxidation states, high natural abundance, flexible structure, and high theoretical specific capacitance. Herein, a porous nanosheet-nanosphere@nanosheet FeNi2-LDH@FeNi2S4 (FNLDH@FNS) core-shell heterostructure was directly prepared on nickel foam (NF) via a two-step hydrothermal method. The prepared electrode material exhibits an outstanding electrochemical performance. The specific capacity (Cs) values are 806 and 450 C g-1 at current density (Dc) values of 1 and 6 A g-1, respectively, revealing a satisfactory magnification performance. In addition, the FNLDH@FNS electrode exhibits a long cycle life with an supercapacitor (SC) retention rate of 92.3% after 5000 cycles at a Dc of 6 A g-1. The FNLDH@FNS//activated carbon (AC) asymmetric SC assembled with FNLDH@FNS (positive electrode) and activated carbon (AC, negative electrode) displays an energy density (Ed) of 36.67 Wh kg-1 and a power density (Pd) of 775.17 W kg-1.
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OBJECTIVE: Secoisolariciresinol diglucoside (SDG) is a phytoestrogen that has been reported to improve postmenopausal osteoporosis (PMOP) caused by estrogen deficiency. In our work, we aimed to investigate the mechanism of SDG in regulating the expressions of ERs on PMOP model rats. METHODS: Ovariectomization (OVX) was used to establish PMOP model in rats. The experiment was allocated to Sham, OVX, SDG and raloxifene (RLX) groups. After 12-week treatment, micro-CT was used to detect the transverse section of bone. Hematoxylin and Eosin staining and Safranine O-Fast Green staining were supplied to detect the femur pathological morphology of rats. Estradiol (E2), interleukin-6 (IL-6), bone formation and bone catabolism indexes in serum were detected using ELISA. Alkaline phosphatase (ALP) staining was used to detect the osteogenic ability of chondrocytes. Immunohistochemistry and Western blot were applied to detect the protein expressions of estrogen receptors (ERs) in the femur of rats. RESULTS: Compared with the OVX group, micro-CT results showed SDG could lessen the injury of bone and improve femoral parameters, including bone mineral content (BMC) and bone mineral density (BMD). Pathological results showed SDG could reduce pathological injury of femur in OVX rats. Meanwhile, SDG decreased the level of IL-6 and regulated bone formation and bone catabolism indexes. Besides, SDG increased the level of E2 and conversed OVX-induced decreased the expression of ERα and ERß. CONCLUSION: The treatment elicited by SDG in OVX rats was due to the reduction of injury and inflammation and improvement of bone formation index, via regulating the expression of E2 and ERs.
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Osteoporose Pós-Menopausa , Osteoporose , Feminino , Humanos , Ratos , Animais , Receptores de Estrogênio , Interleucina-6 , Osteoporose/tratamento farmacológico , Osteoporose/etiologia , Osteoporose/metabolismo , Estrogênios , Densidade Óssea , Osteoporose Pós-Menopausa/tratamento farmacológico , Osteoporose Pós-Menopausa/etiologia , Ovariectomia/efeitos adversosRESUMO
It is important to develop highly efficient and durable Earth-abundant oxygen evolution reaction (OER) electrocatalysts by an energy- and time-saving strategy. Herein, a facile strategy was used to synthesize S-doped nickel-iron oxyhydroxide (S-Ni/FeOOH) nanoparticles on nickel-iron foam (NFF) (S-Ni/FeOOH@NFF), which exhibits a striking enhancement of OER performance compared to Ni/FeOOH@NFF. The free-standing S-Ni/FeOOH@NFF electrode possesses a low overpotential of 229 mV at a current density of 10 mA cm-2, which is 180 mV lower than that of Ni/FeOOH@NFF. In addition, the electrode was also remarkably stable. The current density still remains at 95% after 150 h at a high current density of 100 mA cm-2.
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Nanopartículas , Níquel , Eletrodos , Ferro , OxigênioRESUMO
BACKGROUND: Accurately forecasting patients admitted to the intensive care units (ICUs) after surgery may improve clinical outcomes and guide the allocation of expensive and limited ICU resources. However, studies on predicting postoperative ICU admission in non-cardiac surgery have been limited. OBJECTIVE: To develop and validate a prediction model combining pre- and intraoperative variables to predict ICU admission after non-cardiac surgery. METHODS: This study is based on data from the Vital Signs DataBase (VitalDB) database. Predictors were selected using the least absolute shrinkage and selection operator regression method and logistic regression to develop a nomogram and an online web calculator. The model was internally verified by 1000-Bootstrap resampling. Performance of model was evaluated using area under the receiver operating characteristic curve (AUC), calibration curve and Brier score. The Youden's index was used to find the optimal nomogram's probability threshold. Clinical utility was assessed by decision curve analysis. RESULTS: This study included 5216 non-cardiac surgery patients; of these, 812 (15.6%) required postoperative ICU admission. Potential predictors included age, ASA classification, surgical department, emergency surgery, preoperative albumin level, preoperative urea nitrogen level, intraoperative crystalloid, intraoperative transfusion, intraoperative catheterization, and surgical time. A nomogram was constructed with an AUC of 0.917 (95% CI: 0.907-0.926) and a Brier score of 0.077. The Bootstrap-adjusted AUC was 0.914; the adjusted Brier score was 0.078. The calibration curve showed good agreement between predicted and actual probabilities; and the decision curve indicated clinical usefulness. Finally, we established an online web calculator for clinical application (https://xuzhikun.shinyapps.io/postopICUadmission1/). CONCLUSION: We developed and internally validated an easy-to-use nomogram for predicting ICU admission after non-cardiac surgery.
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Hospitalização , Unidades de Terapia Intensiva , Humanos , Bases de Dados Factuais , Período Pós-Operatório , Curva ROC , Estudos RetrospectivosRESUMO
[This corrects the article DOI: 10.3389/fmolb.2023.1172100.].
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Frequent injections at high concentrations are often required for many therapeutic proteins due to their short in vivo half-life, which usually leads to unsatisfactory therapeutic outcomes, adverse side effects, high cost, and poor patient compliance. Herein we report a supramolecular strategy, self-assembling and pH regulated fusion protein to extend the in vivo half-life and tumor targeting ability of a therapeutically important protein trichosanthin (TCS). TCS was genetically fused to the N-terminus of a self-assembling protein, Sup35p prion domain (Sup35), to form a fusion protein of TCS-Sup35 that self-assembled into uniform spherical TCS-Sup35 nanoparticles (TCS-Sup35 NP) rather than classic nanofibrils. Importantly, due to the pH response ability, TCS-Sup35 NP well retained the bioactivity of TCS and possessed a 21.5-fold longer in vivo half-life than native TCS in a mouse model. As a result, in a tumor-bearing mouse model, TCS-Sup35 NP exhibited significantly improved tumor accumulation and antitumor activity without detectable systemic toxicity as compared with native TCS. These findings suggest that self-assembling and pH responding protein fusion may provide a new, simple, general, and effective solution to remarkably improve the pharmacological performance of therapeutic proteins with short circulation half-lives.
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A new two-dimensional {Cu6}-added polyoxometalate cluster-organic framework (Cu-POMCOF) was prepared by a hydrothermal method from lacunary polyoxoanions and was applied as a solid support for immobilizing MP-11 and Cyt c. The biocomposite complex exhibits higher stability and catalytic activity than the original free enzyme.
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Enzimas Imobilizadas , Enzimas Imobilizadas/químicaRESUMO
The ubiquitinâproteasome system (UPS) plays a key role in maintaining protein homeostasis and bone remodelling. However, the role of deubiquitinating enzymes (DUBs) in bone resorption is still not well defined. Here, we identified the deubiquitinase ubiquitin C-terminal hydrolase 1 (UCHL1) as a negative regulator of osteoclastogenesis by using the GEO database, proteomic analysis, and RNAi. Osteoclast-specific UCHL1 conditional knockout mice exhibited a severe osteoporosis phenotype in an ovariectomized model. Mechanistically, UCHL1 deubiquitinated and stabilized the transcriptional coactivator with PDZ-binding motif (TAZ) at the K46 residue, thereby inhibiting osteoclastogenesis. The TAZ protein underwent K48-linked polyubiquitination, which was degraded by UCHL1. As a substrate of UCHL1, TAZ regulates NFATC1 through a nontranscriptional coactivator function by competing with calcineurin A (CNA) for binding to NFATC1, which inhibits NFATC1 dephosphorylation and nuclear transport to impede osteoclastogenesis. Moreover, overexpression of UCHL1 locally alleviated acute and chronic bone loss. These findings suggest that activating UCHL1 may serve as a novel therapeutic approach targeting bone loss in various bone pathological states.
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Doenças Ósseas Metabólicas , Reabsorção Óssea , Camundongos , Animais , Osteogênese/genética , Proteômica , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Fatores de Transcrição NFATC/genética , Fatores de Transcrição NFATC/metabolismo , Osteoclastos/metabolismo , Reabsorção Óssea/metabolismo , Doenças Ósseas Metabólicas/metabolismo , Camundongos Knockout , Ligante RANK/metabolismoRESUMO
The construction of heterojunction photocatalysts is an effective method to improve photocatalytic efficiency since the potential gradient and built-in electron field established at the junction could enhance the efficiency of charge separation and interfacial charge transfer. Nevertheless, heterojunction photocatalysts with strong built-in electron fields remain difficult to build since the two adjacent constitutes must be satisfied with an appropriate band alignment, redox potential, and carrier concentration gradient. Here, an efficient charge transfer-induced doping strategy is proposed to enhance the heterojunction built-in electron field for stable and efficient photocatalytic performance. Carrier transfer tests show that the rectification ratio of the n-TiO2-X/n-BiOI heterojunction is significantly enhanced after being coated with graphene oxide (GO). Consequently, both the hydrogen production and photodegradation performance of the GO composite heterojunction are considerably enhanced compared with pure TiO2-X, BiOI, and n-TiO2-X/n-BiOI. This work provides a facile method to prepare heterojunction photocatalysts with a high catalytic activity.
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2D bimetal metal organic frameworks (MOFs) are recognized as one of the most promising electrocatalysts for the oxygen evolution reaction (OER). Herein, a facile approach was proposed to construct NiFe-MOF nanosheets on Fe foam (FF). As a self-supporting electrode, the NiFe-MOF/FF electrode shows impressive electrocatalytic OER performance. Specifically, it exhibits an ultra-low overpotential of 216 mV to reach a current density of 50 mA cm-2, and outstanding stability (beyond 50 h at 200 mA cm-2). The excellent performances of NiFe-MOF/FF arise from the highly exposed active centers, the excellent conductivity, and the synergy effect between Ni and Fe. This research provides a promising strategy for the synthesis of multi-metal MOFs as high-efficiency electrocatalysts.
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Constructing a heterostructure is an efficient strategy to enhance the catalytic activity toward the oxygen evolution reaction (OER). Herein, Ce-modified Ni(OH)2 nanoparticles are anchored on Ni-MOF nanosheets by the electrodeposition strategy, forming a self-supporting electrode of Ce-m-Ni(OH)2@Ni-MOF. The Raman spectrum proves that both Ce(OH)3 and Ce doping exist in Ce-modified Ni(OH)2 nanoparticles. The heterostructure possesses an open nanosheet structure, with a good interaction between Ni-MOF and Ce-m-Ni(OH)2, which enables efficient mass/charge transfer and the synergetic effect between Ni and Ce, leading to a high-performance electrocatalyst. Specifically, Ce-m-Ni(OH)2@Ni-MOF achieves current densities of 50 and 100 mA cm-2 at low overpotentials of 219 and 272 mV, respectively, and retains high activity for at least 30 h.