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Advanced optimization strategies for Ir-based oxygen evolution catalysts include morphological regulation, heteroatomic doping, crystal phase control, and support introduction.

Electrochemical production of hydrogen peroxide (H2O2) via two-electron oxygen reduction reaction (ORR) process is emerging as a promising alternative method to the conventional anthraquinone process. To realize high-efficiency H2O2 electrosynthesis, robust and low cost electrocatalysts have been intensively pursued, among which Co-based catalysts attract particular research interests due to the earth-abundance and high selectivity. Here, we provide a comprehensive review on the advancement of Co-based electrocatalyst for H2O2 electroproduction. The fundamental chemistry of 2-electron ORR is discussed firstly for guiding the rational design of electrocatalysts. Subsequently, the development of Co-based electrocatalysts involving nanoparticles, compounds and single atom catalysts is summarized with the focus on active site identification, structure regulation and mechanism understanding. Moreover, the current challenges and future directions of the Co-based electrocatalysts are briefly summarized in this review.

Electrochemical conversion of carbon dioxide into fuel and chemicals with added value represents an appealing approach to reduce the greenhouse effect and realize a carbon-neutral cycle, which has great potential in mitigating global warming and effectively storing renewable energy. The electrochemical CO2 reduction reaction (CO2RR) usually involves multiproton coupling and multielectron transfer in aqueous electrolytes to form multicarbon products (C2+ products), but it competes with the hydrogen evolution reaction (HER), which results in intrinsically sluggish kinetics and a complex reaction mechanism and places higher requirements on the design of catalysts. In this review, the advantages of electrochemical CO2 reduction are briefly introduced, and then, different categories of Cu-based catalysts, including monometallic Cu catalysts, bimetallic catalysts, metal-organic frameworks (MOFs) along with MOF-derived catalysts and other catalysts, are summarized in terms of their synthesis method and conversion of CO2 to C2+ products in aqueous solution. The catalytic mechanisms of these catalysts are subsequently discussed for rational design of more efficient catalysts. In response to the mechanisms, several material strategies to enhance the catalytic behaviors are proposed, including surface facet engineering, interface engineering, utilization of strong metal-support interactions and surface modification. Based on the above strategies, challenges and prospects are proposed for the future development of CO2RR catalysts for industrial applications. Graphical Abstract

Objective: To develop a radiomics nomogram based on multiparametric MRI (mpMRI) to pre-operatively predict lymph-vascular space invasion (LVSI) in patients with early-stage cervical cancer. Methods: This retrospective study included 233 consecutive patients with Stage IB–IIB cervical cancer. According to the ratio of 2:1, 154 patients and 79 patients were randomly assigned to the primary and validation cohorts, respectively. Features with intraclass and interclass correlation coefficient (ICCs) greater than 0.75 were selected for radiomics features. The significant features for predicting LVSI were selected using the least absolute shrinkage and selection operator (LASSO) algorithm based on the primary cohort. The rad-score for each patient was constructed via a linear combination of selected features that were weighted by their respective coefficients. The radiomics nomogram was developed using multivariable logistic regression analysis by incorporating the rad-score and clinical risk factors. Results: A total of 19 radiomics features and 3 clinical risk factors were selected. The rad-score exhibited a good performance in discriminating LVSI with a C-index of 0.76 and 0.81 in the primary and validation cohorts, respectively. The radiomics nomogram also exhibited a good discriminating performance in two cohorts (C-index of 0.78 and 0.82). The calibration curve of the radiomics nomogram demonstrated no significant differences was found between prediction and observation outcomes for the probability of LVSI in two cohorts (p = 0.86 and 0.98, respectively). The decision curve analysis indicated that clinician and patients could benefit from the use of radiomics nomogram and rad-score. Conclusion: The nomogram and rad-score could be used conveniently and individually to predict LVSI in patients with early-stage cervical cancer and facilitate the treatment decision for clinician and patients. Advances in knowledge: The nomogram could pre-operatively predict LVSI in early-stage cervical cancer.

The emerging applications of electrochemical gas sensors (EGSs) in Internet of Things-enabled smart city and personal health electronics bring out a new challenge for common EGSs, such as alcohol fuel cell sensors (AFCSs) to reduce the dependence on a pricy Pt catalyst. Here, for the first time, we propose a low-cost novel N,S-codoped metal catalyst (FeNSC) to accelerate oxygen reduction reaction (ORR) and replace the Pt catalyst in the cathode of an AFCS. The optimal FeNSC shows high ORR activity, stability, and alcohol tolerance. Furthermore, the FeNSC-based AFCS not only demonstrates excellent linearity, low detection limit, high stability, and superior sensitivity to that of the commercial Pt/C-based AFCS but also outperforms commercial Pt/C-based AFCS in the exposed cell regarding great linearity, high sensitivity, and great stability. Such a promising sensor performance not just proves the concept of the FeNSC-based ACFS but enlightens the next-generation designs toward low-cost, highly sensitive, and durable EGSs.

Deploying the application of Au-based catalysts directly on CO2 reduction reactions (CO2 RR) relies on the simultaneous improvement of mass activity (usually lower than 10 mA mg-1Au at -0.6 V) and selectivity. To achieve this target, we herein manipulate the interface of small-size Au (3.5 nm) and CeO2 nanoparticles through adjusting the surface charge of Au and CeO2 . The well-regulated interfacial structure not only guarantees the utmost utilization of Au, but also enhances the CO2 adsorption. Consequently, the mass activity (CO) of the optimal AuCeO2 /C catalyst reaches 139 mA mg-1Au with 97 % CO faradaic efficiency (FECO ) at -0.6 V. Moreover, the strong interaction between Au and CeO2 endows the catalyst with excellent long-term stability. This work affords a charge-guided approach to construct the interfacial structure for CO2 RR and beyond.

Supported metals are widely used as industrial catalysts wherein the supports affect catalytic performances remarkably through either electronic and/or geometric interactions with the metals, and/or providing interfacial synergistic sites. Herein, we observed evidence for interfacial geometric interactions (IGIs) at Pt–C interfaces through a combination of atomic-scale structural analysis, in situ X-ray absorption fine structure, and electrochemical measurements for Pt/C model systems. The IGI has a long-range attribute and affects Pt surface atoms not only at interfacial perimeters but also adjacent to interfaces. The affected Pt surface atoms are proposed to contribute enhanced activity and stability for the oxygen reduction reaction through retarding the formation of strongly adsorbed oxygenated intermediates. Our work provides some necessary information for a better understanding of support effects and catalytically active surface sites.

The development of robust and cost-effective bifunctional oxygen electrocatalysts is of significant importance for the widespread implementation of Zn–air batteries yet remains an immense challenge, which calls for the molecular-level manipulation of active species as well as morphology engineering to accelerate the reversible oxygen reaction dynamics. Herein, a “trimurti” heterostructured cobalt-based hybrid is designed by a facile, one-step phosphorization of layered Co-hexamine metal–organic frameworks. The synergistic effect between cobalt phosphides (Co2P and CoP) and cobalt oxide significantly boosts the electrocatalytic activity of the oxygen redox reaction. Besides, the hierarchically porous structure promotes the accessibility of active species and smooth electron/reactant transportation. Due to these attributes, the as-developed electrocatalyst outperforms the state-of-art non-noble metal catalysts and even noble metal benchmarks with a half-wave potential of 0.86 V for the ORR and an overpotential of 0.37 V at 10 mA cm−2 for the OER. Furthermore, an appealing catalytic performance is also demonstrated in an assembled Zn–air battery, which displays a lower voltage gap of 0.86 V and improved cyclability of 202 h. This work not only affords a competitive bifunctional oxygen electrocatalyst for Zn–air batteries but also highlights the synergetic effect from heterointerfaces in electrocatalysis.

Microsatellite instability (MSI) status is an important indicator for screening patients with endometrial cancer (EC) who have potential Lynch syndrome (LS) and may benefit from immunotherapy. This study aimed to develop a magnetic resonance imaging (MRI)-based radiomics nomogram for the prediction of MSI status in EC.A total of 296 patients with histopathologically diagnosed EC were enrolled, and their MSI status was determined using immunohistochemical (IHC) analysis. Patients were randomly divided into the training cohort (n=236) and the validation cohort (n=60) at a ratio of 8:2. To predict the MSI status in EC, the tumor radiomics features were extracted from T2-weighted images and contrast-enhanced T1-weighted images, which in turn were selected using one-way analysis of variance (ANOVA) and the least absolute shrinkage and selection operator (LASSO) algorithm to build the radiomics signature (radiomics score; radscore) model. Five clinicopathologic characteristics were used to construct a clinicopathologic model. Finally, the nomogram model combining radscore and clinicopathologic characteristics was constructed. The performance of the three models was evaluated using receiver operating characteristic (ROC), calibration, and decision curve analyses (DCA).Totals of 21 radiomics features and five clinicopathologic characteristics were selected to develop the radscore and clinicopathological models. The radscore and clinicopathologic models achieved an area under the curve (AUC) of 0.752 and 0.600, respectively, in the training cohort; and of 0.723 and 0.615, respectively, in the validation cohort. The radiomics nomogram model showed improved discrimination efficiency compared with the radscore and clinicopathologic models, with an AUC of 0.773 and 0.740 in the training and validation cohorts, respectively. The calibration curve analysis and DCA showed favorable calibration and clinical utility of the nomogram model.The nomogram incorporating MRI-based radiomics features and clinicopathologic characteristics could be a potential tool for the prediction of MSI status in EC.

Understanding the dynamic process of interfacial charge transfer prior to chemisorption is crucial to the development of electrocatalysis. Recently, interfacial water has been highlighted in transferring protons through the electrode/electrolyte interface; however, the identification of the related structural configurations and their influences on the catalytic mechanism is largely complicated by the amorphous and mutable structure of the electrical double layer (EDL). To this end, sub-nanometric Pt electrocatalysts, potentially offering intriguing activity and featuring fully exposed atoms, are studied to uncover the elusive electrode/electrolyte interface via operando X-ray absorption spectroscopy during the hydrogen evolution reaction (HER). Our results show that the metallic Pt clusters derived from the reduction of sub-nanometric Pt clusters (SNM-Pt) exhibit excellent HER activity, with an only 18 mV overpotential at 10 mA/cm2 and one-magnitude-higher mass activity than commercial Pt/C. More importantly, a unique Pt-interfacial water configuration with a Pt (from Pt clusters)-O (from water) radial distance of approximately 2.5 A is experimentally identified as the structural foundation for the interfacial proton transfer. Toward high overpotentials, the interfacial water that structurally evolves from "O-close" to "O-far" accelerates the proton transfer and is responsible for the improved reaction rate by increasing the hydrogen coverage.

Background Differentiating adenosquamous carcinoma (ASC) and adenocarcinoma (AC) from squamous cell carcinoma (SCC) precisely is crucial for treatment strategy and prognosis prediction in patients with cervical cancer (CC). Purpose To differentiate ASC and AC from SCC in patients with CC using the apparent diffusion coefficient (ADC) histogram analysis. Material and Methods A total of 118 patients with histologically diagnosed ASC, AC, and SCC were included. The ADC histogram parameters were extracted from ADC maps. Receiver operating characteristic analysis was performed to evaluate the diagnostic performance of each ADC histogram parameter in differentiating the subtypes of CC. The predictors for histologic subtypes were further selected using univariate and multivariate logistic regression analyses. Results The ADCmean, ADCmax, ADCP10, ADCP25, ADCP75, ADCP90, ADCmedian, and ADCmode of the ASC were significantly lower than those of the AC; and ADCkurtosis and ADCskewness of the ASC were lower than those of the SCC. The ADCmean, ADCmax, ADCP10, ADCP25, ADCP75, ADCP90, ADCmedian, and ADCmode of AC were significantly higher than those of the SCC. The ADCP10 and ADCP10 + diameter yielded the AUCs of 0.753 and 0.778 in differentiating ASC from AC. The ADCmedian and ADCmedian + diameter yielded the AUCs of 0.807 and 0.838 in differentiating AC from SCC. The ADCskewness yielded the AUC of 0.713 in differentiating ASC from SCC. Conclusion The ADCP10 and ADCP10 + diameter, ADCmedian, and ADCmedian + diameter performed well in differentiating ASC from AC and AC from SCC, respectively. However, ADCskewness exhibited a limited ability in differentiating ASC from SCC.

Rational regulation on pore structure and active site density plays critical roles in enhancing the performance of Fe-N-C catalysts. As the microporous structure of the carbon substrate is generally regarded as the active site hosts, its hostility to electron/mass transfer could lead to the incomplete fulfillment of the catalytic activity. Besides, the formation of inactive metallic Fe particles during the conventional catalyst synthesis could also decrease the active site density and complicate the identification of real active site. Herein, we developed a facial hydrogen etching methodology to yield single site Fe-N-C catalysts featured with micro/mesoporous hierarchical structure. The hydrogen concentration in pyrolysis process was designated to effectively regulate the pore structure and active site density of the resulted catalysts. The optimized sample achieves excellent ORR catalytic performance with an ultralow H2O2 yield (1%) and superb stability over 10,000 cycles. Our finding provides new thoughts for the rational design of hierarchically porous carbon-based materials and highly promising non-precious metal ORR catalysts.

The electrochemical methanol oxidation reaction (MOR) is of paramount importance for direct methanol fuel cell (DMFC) application, where efficient catalysts are required to facilitate the complicated multiple charge transfer process. The catalyst support not only determines the dispersion status of the catalysts particles, but also exerts great influence on the electronic structure of the catalysts, thereby altering its intrinsic activity. Herein, we demonstrated that nitrogen atoms, assisted by the pre-treatment of carbon matrix with oxidants, can be easily doped into carbon nanotubes at low temperature. The obtained nitrogen-doped carbon nanotubes can effectively improve the dispersion of the supported platinum nanoparticles and facilitate the MOR by modifying the electronic structure of platinum atoms, through catalyst-support interaction.

To determine whether a community-based physical rehabilitation program could improve the prognosis of patients who had undergone percutaneous coronary intervention after acute myocardial infarction, we randomly divided 164 consecutive patients into 2 groups of 82 patients. Patients in the rehabilitation group underwent 3 months of supervised exercise training, then 9 months of community-based, self-managed exercise; patients in the control group received conventional treatment. The primary endpoint was major adverse cardiac events (MACE) during the follow-up period (25 ± 15.4 mo); secondary endpoints included left ventricular ejection fraction, 6-minute walk distance, and laboratory values at 12-month follow-up. During the study period, the incidence of MACE was significantly lower in the rehabilitation group (13.4% vs 24.4%; P These findings suggest that community-based physical rehabilitation significantly reduced MACE risk and improved cardiac function and physical stamina in patients who underwent percutaneous coronary intervention after acute myocardial infarction.

Engineering an electrocatalytic anode material to boost reaction kinetics is highly desirable for the anodic oxygen evolution reaction (OER), which is the major obstacle for high efficiency water electrolysis. Here, we present a novel kind of Zn-doped Co3O4 hollow dodecahedral electrocatalyst. Abundant oxygen vacancy defects are introduced due to the incorporation of Zn2+, which is beneficial for OH− adsorption and the charge transfer reaction during the OER process. Moreover, the increase in surface area caused by the advanced structure of the hollow porous dodecahedra facilitates mass transport by increasing the surface area. The novel strategy proposed in this study provides an efficient way to design high-performance electrocatalysts for water electrolysis. A cheap catalyst that aids water splitting and is made from readily available materials has been developed by researchers in China. Hydrogen releases energy when burned in air, and is therefore a promising source of clean power. Hydrogen can be sourced by splitting water into its constituent atoms, but the chemical reaction separating hydrogen and oxygen, known as the oxygen evolution reaction, is not particularly efficient. Yao Xiao and coworkers from the Changchun Institute of Applied Chemistry developed an oxygen evolution reaction electrocatalyst made from zinc-doped cobalt oxide, Zn-Co3O4. The catalyst has a unique dodecahedral structure, and the team believes it is its large surface area that is responsible for its excellent performance. Unlike many other water-splitting catalysts, the constituent materials of Zn-Co3O4 are cheap and readily available. Cobaltosic oxide hollow dodecahedra with abundant oxygen vacancy defects was synthesized and manifested extraordinary catalytic performance toward the oxygen evolution reaction.

Deploying the application of Au-based catalysts directly on CO

Single-atom FeN

Formic acid decomposition (FAD) is one of the most promising routes for rapid hydrogen (H2) production. Extensive efforts have been taken to develop efficient catalysts, which calls for the simultaneous regulation of the electronic structure and particle size of the catalyst. The former factor determines the intrinsic performance, while the latter corresponds to the active site utilization. Here, an effective preparation strategy, pre-nucleation coupled with in situ reduction, is developed to realize and well-tune both surface electronic states and particle size of the pallidum (Pd) catalyst. Benefiting from the structural merits, the as-prepared catalyst exhibits high mass-specific activity of 8.94 molH2/(gPd·h) with few carbon monoxide (CO) molecules, and the activation energy could reach a value as small as 33.1 kJ/mol. The work not only affords a highly competitive FAD catalyst but also paves a new avenue to the synthesis of ultra-fine metal nanoparticles with tailorable electronic structures.

Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the trachea is very rare and is easily misdiagnosed as a bronchogenic carcinoma or benign tracheal tumor. Here, we report a clinical case where a new clinical approach involving a water-jet hybrid knife was employed in the diagnosis and treatment of primary tracheal MALT lymphoma.

Pyrolyzed Fe-NX/C materials derived from Fe-doped ZIF-8 are recently emerged as promising alternatives to noble metal platinum-based catalysts towards oxygen reduction reaction (ORR) and elucidating the dependacne of Fe source on the active site structure and final ORR performance is highly desirbale for further development of these materials. Here, we designed and synthesized a series of Fe-N-C catalysts using ZIF-8 and various iron salts (Fe(acac)3, FeCl3, Fe(NO3)3) as precusors. We found that the iron precursors, mainly the molecular size, hydrolysis extent, do play a major role in determining the final morphology of Fe, namely forming the Fe-Nx coordination or Fe3C nanoparticles, as well as the site density, therefore, significantly affecting the ORR activity. Among the three iron sources, Fe(acac)3 is most advantageous to the preferential formation of single-atom Fe-Nx active sites and the derived catalyst demonstrated best ORR performance.

Metal-free electrocatalysts have eluded widespread adoption in polymer electrolyte membrane fuel cells due to their far inferior catalytic activity than most non-precious metal-N-C counterparts (M-Nx-C) for oxygen reduction reaction (ORR), despite their distinct advantages over the M-Nx-C catalysts, including lower cost and higher durability. Herein, we develop a rational bottom-up engineering strategy to improve the ORR performance of a metal-free catalyst by constructing a three-dimensional ultrathin N, P dual-doped carbon nanosheet. The resultant catalyst represents unprecedented ORR performance with an onset potential of 0.91 V, half-wave potential of 0.79 V. Impressively, a maximum power output at 579 mW cm−2 is generated in the fuel cell test, the best among reported metal-free catalysts and outperforms most of the M-Nx-C catalysts. The outstanding catalytic performance results from the highly active polarized carbon sites which are induced by selective graphitic nitrogen and phosphorous dual doping. Our findings provide new directions for the exploration of alternatives to Pt and bring a renew interests in the metal-free catalysts.

Lacking strategies to simultaneously address the intrinsic activity, site density, electrical transport, and stability problems of chalcogels is restricting their application in catalytic hydrogen production. Herein, we resolve these challenges concurrently through chemically activating the molybdenum disulfide (MoS2) surface basal plane by doping with a low content of atomic palladium using a spontaneous interfacial redox technique. Palladium substitution occurs at the molybdenum site, simultaneously introducing sulfur vacancy and converting the 2H into the stabilized 1T structure. Theoretical calculations demonstrate the sulfur atoms next to the palladium sites exhibit low hydrogen adsorption energy at –0.02 eV. The final MoS2 doped with only 1wt% of palladium demonstrates exchange current density of 805 μA cm−2 and 78 mV overpotential at 10 mA cm−2, accompanied by a good stability. The combined advantages of our surface activating technique open the possibility of manipulating the catalytic performance of MoS2 to rival platinum. While water reduction may provide a carbon-neutral means to produce hydrogen gas, there is a scarcity of efficient, earth-abundant electrocatalysts. Here, the authors add palladium into MoS2 materials to activate and stabilize the conductive basal plane to improve the electrocatalytic activity.

Herein, a novel binuclear active site structure, Co2NxCy, is intentionally designed and successfully fabricated to efficiently catalyze the oxygen reduction reaction (ORR), which is achieved by precisely controlling the atomic scale structure of bimetal-organic frameworks before pyrolysis. Through discovering a two-atom site with Co-Co distance at 2.1–2.2 A from aberration-corrected scanning transmission electron microscopy (STEM), as well as a novel shortened Co-Co path (2.12 A) from the X-ray absorption spectroscopy, we for the first time identified the binuclear Co2NX site in the pyrolyzed catalyst. Combined with density functional theory (DFT) calculation, the structure is further confirmed as Co2N5. Excitingly, the Co2N5 site performs approximately 12 times higher activity than the conventional CoN4 site and the corresponding catalyst shows unprecedented catalytic activity in acidic electrolyte with half-wave potential of 0.79 V, approaching the commercial Pt/C catalyst and presenting the best one among the Co-N-C catalysts. Theoretical density functional theory calculations reveal that the novel binuclear site exhibits considerably reduced thermodynamic barrier towards ORR, thus contributing to the much higher intrinsic activity. Our finding opens up a new path to design efficient M-Nx/C catalysts, thus pushing the fuel cell industry field one step ahead.

Developing highly efficient, low-cost oxygen reduction catalysts, especially in acidic medium, is of significance toward fuel cell commercialization. Although pyrolyzed Fe-N-C catalysts have been regarded as alternatives to platinum-based catalytic materials, further improvement requires precise control of the Fe-Nx structure at the molecular level and a comprehensive understanding of catalytic site structure and the ORR mechanism on these materials. In this report, we present a microporous metal–organic-framework-confined strategy toward the preferable formation of single-atom dispersed catalysts. The onset potential for Fe-N-C is 0.92 V, comparable to that of Pt/C and outperforming most noble-metal-free catalysts ever reported. A high-spin Fe3+-N4 configuration is revealed by the 57Fe Mossbauer spectrum and X-ray absorption spectroscopy for Fe L-edge, which will convert to Fe2+-N4 at low potential. The in situ reduced Fe2+-N4 moiety from high-spin Ox-Fe3+-N4 contributes to most of the ORR activity due t...

Spiro[2,2-dimethyl-benzofuran, bicyclo [4.2.0] octane]-7'-one with fused and spirocyclic oxygen-containing rigid skeleton structure is obtained via Wolff rearrangement and cycloaddition with good yields. Then Spiro[2,2-dimethyl-benzofuran,-hexahydro- isobenzofuran]-7'-one is synthesized by further Baeyer-Villiger oxidation. These two kinds of products have a special fused and spirocyclic oxygen-containing rigid skeleton structure and are reported by our group.

BACKGROUND Reintubation is associated with increased hospital mortality. It is necessary to identify risk factors associated with reintubation. METHODS A prospective observational study was performed in a respiratory intensive care unit. Medical patients who successfully completed a spontaneous breathing trial (SBT) were enrolled. Before extubation, age, gender, vital signs, acute physiology and chronic health evaluation II score, SBT attempts, cough peak flow, arterial blood gas tests and albumin were recorded. RESULTS We enrolled 139 patients. Of these, 22 (15.8%) patients experienced reintubation within 72 hours after extubation. SBT attempts (odds ratio [OR] = 1.446, 95% confidence interval [CI]: 1.095-1.910), cough peak flow (OR = 0.975, 95% CI: 0.956-0.994) and albumin (OR = 0.847, 95% CI: 0.752-0.954) were independent risk factors for reintubation. In patients with 1, 2 and ≥3 SBT attempts, reintubation rates were 7.3%, 21.1% and 45.8%, respectively (P