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The electrochemical oxidation of small molecules to generate value‐added products has gained enormous interest in recent years because of the advantages of benign operation conditions, high conversion efficiency and selectivity, the absence of external oxidizing agents, and eco‐friendliness. Coupling the electrochemical oxidation of small molecules to replace oxygen evolution reaction (OER) at the anode and the hydrogen evolution reaction (HER) at the cathode in an electrolyzer would simultaneously realize the generation of high‐value chemicals or pollutant degradation and the highly efficient production of hydrogen. This Minireview presents an introduction on small‐molecule choice and design strategies of electrocatalysts as well as recent breakthroughs achieved in the highly efficient production of hydrogen. Finally, challenges and future orientations are highlighted. [ABSTRACT FROM AUTHOR]

The electrochemical oxidation of small molecules to generate value‐added products has gained enormous interest in recent years because of the advantages of benign operation conditions, high conversion efficiency and selectivity, the absence of external oxidizing agents, and eco‐friendliness. Coupling the electrochemical oxidation of small molecules to replace oxygen evolution reaction (OER) at the anode and the hydrogen evolution reaction (HER) at the cathode in an electrolyzer would simultaneously realize the generation of high‐value chemicals or pollutant degradation and the highly efficient production of hydrogen. This Minireview presents an introduction on small‐molecule choice and design strategies of electrocatalysts as well as recent breakthroughs achieved in the highly efficient production of hydrogen. Finally, challenges and future orientations are highlighted. [ABSTRACT FROM AUTHOR]

Main‐group (s‐ and p‐block) metals are generally regarded as catalytically inactive due to the delocalized s/p‐band. Herein, we successfully synthesized a p‐block antimony single‐atom catalyst (Sb SAC) with the Sb−N4 configuration for efficient catalysis of the oxygen reduction reaction (ORR). The obtained Sb SAC exhibits superior ORR activity with a half‐wave potential of 0.86 V and excellent stability, which outperforms most transition‐metal (TM, d‐block) based SACs and commercial Pt/C. In addition, it presents an excellent power density of 184.6 mW cm−2 and a high specific capacity (803.5 mAh g−1) in Zn–air battery. Both experiment and theoretical calculation manifest that the active catalytic sites are positively charged Sb−N4 single‐metal sites, which have closed d shells. Density of states (DOS) results unveil the p orbital of the atomically dispersed Sb cation in Sb SAC can easily interact with O2‐p orbital to form hybrid states, facilitating the charge transfer and generating appropriate adsorption strength for oxygen intermediates, lowering the energy barrier and modulating the rate‐determining step. This work sheds light on the atomic‐level preparing p‐block Sb metal catalyst for highly active ORR, and further provides valuable guidelines for the rational design of other main‐group‐metal SACs. [ABSTRACT FROM AUTHOR]

Main‐group (s‐ and p‐block) metals are generally regarded as catalytically inactive due to the delocalized s/p‐band. Herein, we successfully synthesized a p‐block antimony single‐atom catalyst (Sb SAC) with the Sb−N4 configuration for efficient catalysis of the oxygen reduction reaction (ORR). The obtained Sb SAC exhibits superior ORR activity with a half‐wave potential of 0.86 V and excellent stability, which outperforms most transition‐metal (TM, d‐block) based SACs and commercial Pt/C. In addition, it presents an excellent power density of 184.6 mW cm−2 and a high specific capacity (803.5 mAh g−1) in Zn–air battery. Both experiment and theoretical calculation manifest that the active catalytic sites are positively charged Sb−N4 single‐metal sites, which have closed d shells. Density of states (DOS) results unveil the p orbital of the atomically dispersed Sb cation in Sb SAC can easily interact with O2‐p orbital to form hybrid states, facilitating the charge transfer and generating appropriate adsorption strength for oxygen intermediates, lowering the energy barrier and modulating the rate‐determining step. This work sheds light on the atomic‐level preparing p‐block Sb metal catalyst for highly active ORR, and further provides valuable guidelines for the rational design of other main‐group‐metal SACs. [ABSTRACT FROM AUTHOR]

Many test coverage metrics have been proposed to measure the deep neural network (DNN) testing effectiveness, including structural coverage and nonstructural coverage. These test coverage metrics are proposed based on the fundamental assumption: They are correlated with test effectiveness. However, the fundamental assumption is still not validated sufficiently and reasonably, which brings question on the usefulness of DNN test coverage. This paper conducted a revisiting study on the existing DNN test coverage from the test effectiveness perspective, to effectively validate the fundamental assumption. Here, we carefully considered the diversity of subjects, three test effectiveness criteria, and both typical and state‐of‐the‐art test coverage metrics. Different from all the existing studies that deliver negative conclusions on the usefulness of existing DNN test coverage, we identified some positive conclusions on their usefulness from the test effectiveness perspective. In particular, we found the complementary relationship between structural and nonstructural coverage and identified the practical usage scenarios and promising research directions for these existing test coverage metrics. [ABSTRACT FROM AUTHOR]

Electrocatalytic water splitting driven by renewable electricity has attracted great interest in recent years for producing hydrogen with high-purity. However, the practical applications of this technology are limited by the development of electrocatalysts with high activity, low cost, and long durability. In the search for new electrocatalysts, computational chemistry has made outstanding contributions by providing fundamental laws that govern the electron behavior and enabling predictions of electrocatalyst performance. This review delves into theoretical studies on electrochemical water-splitting processes. Firstly, we introduce the fundamentals of electrochemical water electrolysis and subsequently discuss the current advancements in computational methods and models for electrocatalytic water splitting. Additionally, a comprehensive overview of benchmark descriptors is provided to aid in understanding intrinsic catalytic performance for water-splitting electrocatalysts. Finally, we critically evaluate the remaining challenges within this field. [ABSTRACT FROM AUTHOR]

The interfacial synergy effect caused by the space charge transfer of heterojunctions can effectively modify the catalytic activity. Herein, a composite heterojunction catalyst of CoTe 2 /CoP with moderate Gibbs free energy of hydrogen adsorption is designed based on interfacial effects driven by work function difference between CoTe 2 and CoP. As expected, CoTe 2 /CoP only needs overpotentials of 80 mV at 10 mA cm−2 and stability for continuous catalysis at the current density of 100 mA cm−2 for 20 h in hydrogen evolution reaction (HER). The experimental results and theory calculations identify that the built-in field drives the transfer of electrons from CoTe 2 to CoP at the interface, which realizes electronic redistribution with increased electron density on the Co atoms in CoP and optimizes the adsorption-free energy of the reaction intermediates, thereby, accelerating HER kinetics. Besides, the CoTe 2 /CoP heterostructure also behaves the excellent catalytic activity towards water splitting. [Display omitted] • CoTe 2 /CoP is prepared via one-step phosphotellurization method. • Built-in field drives the transfer of electrons from CoTe 2 to CoP at the interface. • Electronic redistribution optimizes the adsorption-free energy of the reaction intermediates. • CoTe 2 /CoP exhibits the boosted hydrogen evolution reaction (HER) performance. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high‐efficiency AWE. Herein, WC1‐x/Mo2C nanoparticle‐embedded carbon nanofiber (WC1‐x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1‐x, the electrocatalysts of WC1‐x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1‐x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm−2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d‐band center for WC1‐x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built‐in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields. [ABSTRACT FROM AUTHOR]

Alkaline water electrolysis (AWE) plays a crucial role in the realization of a hydrogen economy. The design and development of efficient and stable bifunctional catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are pivotal to achieving high‐efficiency AWE. Herein, WC1‐x/Mo2C nanoparticle‐embedded carbon nanofiber (WC1‐x/Mo2C@CNF) with abundant interfaces is successfully designed and synthesized. Benefiting from the electron transfer behavior from Mo2C to WC1‐x, the electrocatalysts of WC1‐x/Mo2C@CNF exhibit superior HER and OER performance. Furthermore, when employed as anode and cathode in membrane electrode assembly devices, the WC1‐x/Mo2C@CNF catalyst exhibits enhanced catalytic activity and remarkable stability for 100 hours at a high current density of 200 mA cm−2 towards overall water splitting. The experimental characterizations and theoretical simulation reveal that modulation of the d‐band center for WC1‐x/Mo2C@CNF, achieved through the asymmetric charge distribution resulting from the built‐in electric field induced by work function, enables optimization of adsorption strength for hydrogen/oxygen intermediates, thereby promoting the catalytic kinetics for overall water splitting. This work provides promising strategies for designing highly active catalysts in energy conversion fields. [ABSTRACT FROM AUTHOR]

Nickel hydroxide (Ni(OH)2) has been identified as one of the best promising electrocatalyst candidates for urea oxidation reaction (UOR) due to its flexible structures, wide compositions, and abundant 3d electrons under alkaline conditions. However, its layered structure with limited exposed edge sites severely hinders further improvement of the UOR activity. Herein, oxygen‐vacancy rich and vanadium doped Ni(OH)2 (Ovac‐V‐Ni(OH)2) catalysts are prepared and synergistically boost the urea electrooxidation. Vanadium doping contributes more exposed active sites, and simultaneously generates oxygen vacancies, switching the rate‐determining step of UOR from *COOH deprotonation to the N–H bond cleavage process and lowering the thermodynamic barrier by around 1.13 eV. The novel Ovac‐V‐Ni(OH)2 demonstrates good electrocatalytic performances with a working potential of 1.47 V at a high current density of 100 mA cm−2. Synergistic engineering of doping and oxygen vacancy is a promising strategy for designing efficient UOR electrocatalysts. [ABSTRACT FROM AUTHOR]

Background: The early clinical diagnosis of spinal infections in elderly patients with recessive or atypical symptoms is difficult. Klebsiella aerogenes is a common opportunistic bacterium that can infect the respiratory tract, urinary tract, and even the central nervous system. However, whether it can infect the lumbar spine has not been previously described.Case Presentation: In this paper, we report the case of a 69-year-old female patient with osteoporosis who was initially diagnosed with hemolytic anemia. Later, she was diagnosed with K. aerogenes infection of the lumbar spine based on imaging combined with blood culture and metagenome next-generation sequencing (mNGS) detection. After precise medication, the lumbar degeneration was improved.Conclusions: Bacterial infection should therefore be considered in cases of lumbar degenerative disease in middle-aged and elderly patients. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases are the leading cause of death worldwide. During the development of cardiovascular diseases, hypoxia plays a crucial role. Hypoxia-inducible factors (HIFs) are the key transcription factors for adaptive hypoxic responses, which orchestrate the transcription of numerous genes involved in angiogenesis, erythropoiesis, glycolytic metabolism, inflammation, and so on. Recent studies have dissected the precise role of cell-specific HIFs in the pathogenesis of hypertension, atherosclerosis, aortic aneurysms, pulmonary arterial hypertension, and heart failure using tissue-specific HIF-knockout or -overexpressing animal models. More importantly, several compounds developed as HIF inhibitors or activators have been in clinical trials for the treatment of renal cancer or anemia; however, little is known on the therapeutic potential of these inhibitors for cardiovascular diseases. The purpose of this review is to summarize the recent advances on HIFs in the pathogenesis and pathophysiology of cardiovascular diseases and to provide evidence of potential clinical therapeutic targets. [ABSTRACT FROM AUTHOR]