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Abstract Anion exchange membrane fuel cells (AEMFCs) have been hailed as a promising hydrogen energy technology due to high energy conversion efficiency, zero carbon emission and the potential independence on scare and expensive noble metal electrocatalysts. A variety of platinum group metal (PGM)‐free catalysts has been developed with superior catalytic performance to noble metal benchmarks toward cathodic oxygen reduction reactions (ORR). However, PGM electrocatalysts still dominate the anodic catalyst research because the kinetics of hydrogen oxidation reaction (HOR) are two or three orders of magnitude slower than in that acidic media. Therefore, it is urgently desirable to improve noble metal utilization efficiency and/or develop high‐performance PGM‐free electrocatalysts for HOR, thus promoting the real‐world implementation of AEMFCs. In this review, the current research progress of electrocatalysts for HOR in alkaline media is summarized. We start with the discussion on the current HOR reaction mechanisms and existing controversies. Then, methodologies to improve the HOR performance are reviewed. Following these principles, the recently developed HOR electrocatalysts including PGM and PGM‐free HOR electrocatalysts in alkaline media are systematically introduced. Finally, we put forward the challenges and prospects in the field of HOR catalysis.

Abstract The limited durability of metal-nitrogen-carbon electrocatalysts severely restricts their applicability for the oxygen reduction reaction in proton exchange membrane fuel cells. In this study, we employ the chemical vapor modification method to alter the configuration of active sites from FeN4 to the stable monosymmetric FeN2+N’2, along with enhancing the degree of graphitization in the carbon substrate. This improvement effectively addresses the challenges associated with Fe active center leaching caused by N-group protonation and free radicals attack due to the 2-electron oxygen reduction reaction. The electrocatalyst with neoteric active site exhibited excellent durability. During accelerated aging test, the electrocatalyst exhibited negligible decline in its half-wave potential even after undergoing 200,000 potential cycles. Furthermore, when subjected to operational conditions representative of fuel cell systems, the electrocatalyst displayed remarkable durability, sustaining stable performance for a duration exceeding 248 h. The significant improvement in durability provides highly valuable insights for the practical application of metal-nitrogen-carbon electrocatalysts.

The usage of cheap crude H2 in proton-exchange membrane fuel cells (PEMFCs) is still unrealistic to date, due to the suffering of the current Pt based nano-catalysts from impurities such as CO in anode. Recently, synergistic active sites between single atom (SA) and nanoparticle (NP) have been found to be promising for overcoming the poisoning problem. However, lengthening the nanoparticle-single atom (SA–NP) interface, i.e., constructing high density synergistic active sites, remains highly challenging. Herein, we present a new strategy based on molecular fusion strategy to create abundant SA–NP interfaces, with high density SA–NP interfaces created on a two dimensional nitrogen doped carbon nanosheets (Ir-SACs&NPs/NC). Owing to the abundance of SA–NP interface sites, the catalyst was empowered with a high tolerance towards up to 1000 ​ppm CO in H2 feed. These findings provide guidelines for the design and construction of active and anti-poisoning catalysts for PEMFC anode.

Abstract Background Deep learning (DL), a specialized form of machine learning (ML), is valuable for forecasting survival in various diseases. Its clinical applicability in real-world patients with gastric cancer (GC) has yet to be extensively validated. Methods A combined cohort of 11,414 GC patients from the Surveillance, Epidemiology and End Results (SEER) database and 2,846 patients from a Chinese dataset were utilized. The internal validation of different algorithms, including DL model, traditional ML models, and American Joint Committee on Cancer (AJCC) stage model, was conducted by training and testing sets on the SEER database, followed by external validation on the Chinese dataset. The performance of the algorithms was assessed using the area under the receiver operating characteristic curve, decision curve, and calibration curve. Results DL model demonstrated superior performance in terms of the area under the curve (AUC) at 1, 3, and, 5 years post-surgery across both datasets, surpassing other ML models and AJCC stage model, with AUCs of 0.77, 0.80, and 0.82 in the SEER dataset and 0.77, 0.76, and 0.75 in the Chinese dataset, respectively. Furthermore, decision curve analysis revealed that the DL model yielded greater net gains at 3 years than other ML models and AJCC stage model, and calibration plots at 3 years indicated a favorable level of consistency between the ML and actual observations during external validation. Conclusions DL-based model was established to accurately predict the survival rate of postoperative patients with GC.

The electrochemical carbon dioxide reduction (ECR) to profoundly diminished chemical entities offers a compelling avenue for transforming sporadic energy resources into enduring fuels while forging an enclosed anthropogenic carbon cycle. Metal-organic frameworks (MOFs) has been extensively investigated as a promising multifunctional material for ECR. Notably, two-dimensional (2D) MOFs attract particular research attention due to their specific chemical and structural properties, i.e., enhanced electrical conductivity, increased open sites, improved mass transport and tunable interfacial environments. In this review, the recent progress of 2D MOFs for ECR is summarized. We begin with the introduction of the synthetic strategies of 2D MOFs. Then, we mainly focus on the advanced 2D MOF electrocatalysts for ECR in recent years, which are clarified by the products. The mechanism underlying the conversion of carbon dioxide (CO2) into carbon products, the factors influencing product formation and a summary of selected 2D MOF catalysts and their synthetic methods are presented. By consolidating the potential factors contributing to the products, we anticipate that the review will offer fresh opportunities for further advancements in CO2 reduction with 2D MOF catalysts.

Abstract Exposure to fine particulate matter (PM2.5) is linked to lung cancer incidence and mortality. However, the impact of PM2.5 exposure on lung cancer patients after lobectomy, which remains the primary treatment for early-stage lung cancer, is unknown. Therefore, we investigated the correlation between PM2.5 exposure and the survival of lung cancer patients after lobectomy. This study included 3,327 patients with lung cancer who underwent lobectomy procedures. We converted residential addresses into coordinates and estimated individual patients' daily PM2.5 and O3 exposure levels. A Cox multivariate regression model was used to analyze the specific monthly association between PM2.5 exposure and lung cancer survival. Every 10 μg/m3 increase in monthly PM2.5 concentration in the first and second months after lobectomy increased the risk of death (hazard ratio [HR]: 1.043, 95% confidence interval [CI]: 1.019–1.067 and HR: 1.036, 95% CI: 1.013–1.060, respectively). Non-smokers, younger patients, and patients with longer hospitalization durations had worse survival rates when exposed to greater concentrations of PM2.5. High postoperative PM2.5 exposure immediately after lobectomy reduced the survival of patients with lung cancer. Patients living in areas with high PM2.5 should be offered the opportunity to transfer to areas with better air quality after undergoing lobectomies, to prolong their survival times.

The poor stability of ruthenium-based catalysts has greatly hampered their application in polymer electrolyte membrane water electrolysis. Here, the authors uncover the decisive role of reaction route on catalytic performance, which enables the screening of efficient ruthenium-based water oxidation catalysts.

Abstract Background Fusobacterium nucleatum (F. nucleatum) often colonizes cancerous gastric tissues and is characterized by the promotion of platelet aggregation and the development of visceral thrombosis. Venous thromboembolism (VTE) leads to a significant increase in the mortality of gastric cancer (GC) patients. However, the relationship between the colonization of F. nucleatum and the prognosis of GC patients is still unknown. Aim The aim of this study was to explore whether the colonization of F. nucleatum is related to the prognosis of GC patients complicated with VTE and to explore other potential risk factors. Methods From 2017–2021, the data of 304 patients with new VTEs during the treatment of GC at the Affiliated Cancer Hospital of Zhengzhou University were collected. Fluorescence in situ hybridization of F. nucleatum was performed on pathological sections of cancer tissues from the patients. Survival analysis methods, including the Kaplan‒Meier method and Cox proportional hazard model, were performed. Results F. nucleatum colonization was significantly associated with splanchnic vein thrombosis, higher platelet-lymphocyte ratio (PLR), and lower absolute lymphocyte count. In the multivariable Cox model, F. nucleatum colonization was found to be an independent risk factor for the prognosis of GC, with an adjusted HR of 1.77 (95% CI, 1.17 to 2.69 [P = 0.007]). In addition, patients with high PLR (HR: 2.65, P = 0.004) or VTE occurring during four cycles of chemotherapy (HR: 2.32, P = 0.012) exhibited shorter survival. Conversely, those experiencing VTE later (HR per month from diagnosis of GC: 0.95, P = 0.006) or using IVC filters (HR: 0.27, P = 0.011) had longer survival. Conclusion Colonization of F. nucleatum in GC tissues was associated with lower absolute lymphocyte count and higher PLR in GC patients with VTE. F. nucleatum colonization also appeared to be associated with the development of VTE in specific sites, in particular the splanchnic vein. Colonization of F. nucleatum may potentially represent an independent predictor of poor prognosis in GC patients. Additional research is necessary to validate these findings.

Abstract CO impurity‐induced catalyst deactivation has long been one of the biggest challenges in proton‐exchange membrane fuel cells, with the poisoning phenomenon mainly attributed to the overly strong adsorption on the catalytic site. Here, we present a mechanistic study that overturns this understanding by using Rh‐based single‐atom catalysis centers as model catalysts. We precisely modulated the chelation structure of the Rh catalyst by coordinating Rh with C or N atoms, and probed the reaction mechanism by surface‐enhanced Raman spectroscopy. Direct spectroscopic evidence for intermediates indicates that the reactivity of adsorbed OH*, rather than the adsorption strength of CO*, dictates the CO electrocatalytic oxidation behavior. The RhN4 sites, which adsorb the OH* intermediate more weakly than RhC4 sites, showed prominent CO oxidation activity that not only far exceeded the traditional Pt/C but also the RhC4 sites with similar CO adsorption strength. From this study, it is clear that a paradigm shift in future research should be considered to rationally design high‐performance CO electro‐oxidation reaction catalysts by sufficiently considering the water‐related reaction intermediate during catalysis.

Proton exchange membrane fuel cells (PEMFCs), which can directly convert chemical energy into electrical energy with high efficiency and zero carbon emission, have attracted extensive attention. Unfortunately, the sluggish kinetics of oxygen reduction reaction (ORR) on the cathode leads to considerable overpotential and thus severely lowering its operational energy conversion efficiency. Although Pt-based catalysts have been developed as the most efficient catalyst towards ORR, however, their stability is far from the application requirements, which hinders the large-scale application of PEMFCs to a certain extent. Thus, improving the stability of Pt-based catalysts is urgently desirable to advance the widespread commercialization of fuel cells. This review focuses on the stability of Pt-based ORR catalysts in PEMFCs, from the perspectives of catalyst degradation mechanism and stability improvement strategies. It is aimed at providing research directions for the development of stable Pt-based catalysts. Firstly, degradation of metal nanoparticles (dissolution, migration, agglomeration, Ostwald ripening, etc.) and corrosion of carbon supports are introduced. To conquer the two attenuation mechanisms, stability improvement strategies such as constructing intermetallic compounds, enhancing metal-support interaction and the modification of carbon support, are summarized in detail. In addition, some typical stability characterization techniques are outlined. Finally, we discuss the challenges and possible research directions in the future. We hope this review can help readers gain insights into the stability issues of Pt-based ORR nanocatalysts and encourage research that will enable the commercialization of PEMFCs.

A 13-valent pneumococcal conjugate vaccine against invasive pneumococcal disease (IPD) was introduced in China in April 2017. We describe 105 children

ObjectiveTo investigate the possible impact of lockdown policies on the diagnosis and treatment of cancer patients in Henan, China.Design, Setting, and ParticipantsWe collected data from the Henan Cancer Hospital, affiliated with Zhengzhou University. The monthly numbers of inpatient admissions from January 2014 to December 2019 were used to forecast the number of inpatient admissions in 2020, which was then compared to the actual number of patients admitted during the pandemic to evaluate how the actual number diverges from this forecast. We conducted an interrupted time series analysis using the autoregressive integrated moving average (ARIMA) model.Main Outcomes and MeasuresFor specific diagnoses, treatment modalities, and age groups, we compared the changes in monthly admissions after the pandemic with the forecasted changes from the model.ResultsThe observed overall monthly number of inpatient admissions decreased by 20.2% [95% confidence interval (CI), 11.7–27.2%], 78.9% (95% CI, 77.3–80.4%), and 40.9% (95% CI, 35.6–45.5%) in January, February, and March 2020, respectively, as compared with those predicted using the ARIMA model. After the lockdown, visits for all treatment modalities decreased sharply. However, apparent compensation and recovery of the backlog appeared in later surgeries. As a result, the number of patients who underwent surgery in 2020 (30,478) was close to the number forecasted by the ARIMA model (30,185). In the same period, patients who received other treatments or underwent examinations were 106,074 and 36,968, respectively; the respective numbers that were forecasted by ARIMA were 127,775 and 60,025, respectively. These findings depict a decrease of 16.9 and 38.4% in patients who received other treatments or underwent examinations only, respectively. Regarding diagnosis, the reported incidence of various cancers decreased dramatically in February, with varying extent and speed of recovery.Conclusion and RelevanceThe COVID-19 pandemic has significantly delayed the diagnosis and treatment of cancer in Henan, China. Long-term research should be conducted to assess the future effects of lockdown policies.

The local electronic configuration of active sites in molybdenum disulfide (MoS2) could significantly alter the intrinsic activity towards hydrogen evolution reaction (HER). Herein, we report that the HER performance of MoS2 electrocatalysts was boosted via bismuth and palladium co-doping. The introduction of heteroatom Bi successfully altered the local electronic configuration of S atoms in the MoS2 inert basal plane to form an electron-enriched environment, conducive to boost active site density and proton adsorption, as experimentally verified by X-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). Furthermore, after activating the MoS2 via Pd doping, a phase transition to stable 1 T phase occurred which was verified by Raman. In acidic media, the as-prepared Bi/Pd-MoS2 catalyst exhibited excellent electrochemical HER performance in terms of a low overpotential of -114 mV at a current density of 10 mA cm−2, a small Tafel slope of 65 mV dec−1, and outstanding long-term stability.

H2 energy as an alternative to fossil fuels requires cost-effective catalysts with fast kinetics for splitting water. Here, authors design MoS2 materials with di-anionic surfaces to improve the electrocatalytic H2 evolution activities.

For large-scale and sustainable water electrolysis, it is of great significance to develop cheap and efficient electrocatalysts that can replace platinum. Currently, it is difficult for most catalysts to combine high activity and stability. To solve this problem, we use cobalt to regulate the electronic structure of ruthenium to achieve high activity, and use carbon matrix to protect alloy nanoparticles to achieve high stability. Herein, based on the zeolitic imidazolate frameworks (ZIFs), a novel hybrid composed of RuCo alloy nano-particles and N-doped carbon was prepared via a facile pyrolysis-displacement-sintering strategy. Due to the unique porous structure and multi-component synergy, the optimal RuCo500@NC750 material in both acidic and alkaline media exhibited eminent HER catalytic activity. Notably, the 3-RuCo500@NC750 obtained a current density of 10 mA cm−2 at 22 mV and 31 mV in 0.5 M H2SO4 and 1.0 M KOH, respectively, comparable to that of the reference Pt/C catalyst. Furthermore, the Tafel slopes of the catalyst are 52 mV Dec−1 and 47 mV Dec−1, respectively, under acid and alkali conditions, and the catalyst has good stability, indicating that it has broad application prospects in practical electrolytic systems. This work contributes to understanding the role of carbon-supported polymetallic alloy in the electrocatalytic hydrogen evolution process, and provides some inspiration for the development of a high efficiency hydrogen evolution catalyst.

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.