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Methanol‐electrooxidation‐reaction (MOR) to value‐added formate is a promising alternative to water oxidation for cost‐efficient hydrogen production. It is generally proposed that the MOR kinetics on Ni‐based catalysts are highly limited by the transition rate of Ni(OH)2/NiOOH. Yet, how to define the catalyst following the direct pathway without Ni2+/Ni3+ transition remains challenging. Herein, a core@shell heterostructured NiMoPx@Ni5P4 catalyst is developed to selectively promote the MOR at a large current density (> 500 mA cm−2). A series of operando spectroscopic studies reveal negligible formation of NiOOH with 1.0 m methanol in a wide potential range, where MOR is predominant. Theoretical calculations demonstrate that the Ni‐P site of NiMoPx@Ni5P4 favors the adsorption of *CH3OH over *OH while the heterostructure contributes to the significantly reduced energy barrier of *OCH3 →*OCH2, hence promoting the MOR along a direct pathway without the formation of NiOOH. Moreover, further study suggests that the catalyst also performs well toward cathodic hydrogen evolution reaction (HER). As a result, an electrode pair of NiMoPx@Ni5P4//NiMoPx@Ni5P4 is employed to enable concurrent MOR/HER electrolysis at 1.81 V to yield formate/H2 with FEs of ca. 90/100% and long‐term (100‐h) sustainability at 500 mA cm−2 under the industrial conditions (6.0 m KOH, 65 °C). [ABSTRACT FROM AUTHOR]

Atherosclerosis is a chronic lipid-driven inflammatory disease characterized by infiltration of large numbers of macrophages. The progression of the disease is closely related to the status of macrophages in atherosclerotic plaques. Recent advances in plaque analysis have revealed a subpopulation of macrophages that express high levels of triggering receptor expressed on myeloid cells 2 (TREM2). Although TREM2 is known to play a critical role in inflammation, lipid metabolism, and tissue repair, its role in atherosclerosis is still not fully understood. Recent studies have shown that TREM2 promotes macrophage cholesterol uptake and efflux, enhances efferocytosis function, regulates inflammation and metabolism, and promotes cell survival, all of which are significant functions in atherosclerosis. In early plaques TREM2 promotes lipid uptake and increases lesion size. In advanced plaques TREM2 promotes macrophage survival and increases plaque stability. The dualistic nature of TREM2 in atherosclerosis, where it can exert both protective effect and a side effect of increased lesion size, presents a complex but crucial area of study. Understanding these dual roles could help in the development of new therapeutic strategies to modulate TREM2 activity and utilize its atheroprotective function while mitigating its deleterious effects. In this review, we discuss the roles and mechanisms of TREM2 during different stages of atherosclerotic plaques, as well as the potential applications of TREM2 in the diagnosis and treatment of atherosclerosis. [ABSTRACT FROM AUTHOR]

Semi-covariance has attracted significant attention in recent years and is increasingly employed to elucidate statistical phenomena exhibiting fluctuations, such as the similarity or difference in charge patterns of spike proteins among coronaviruses. In this study, by examining values above and below the average/mean based on the positive and negative charge patterns of amino acid residues in the spike proteins of SARS-CoV-2 and its current circulating variants, the proposed methods offer profound insights into the nonlinear evolving trends in those viral spike proteins. Our study indicates that the charge span value can predict the infectivity of the virus and the charge density can estimate the virulence of the virus, and both predicated infectivity and virulence appear to be associated with the capability of viral immune escape. This semi-covariance coefficient analysis may be used not only to predict the infectivity, virulence and capability of immune escape for coronaviruses but also to analyze the functionality of other viral proteins. This study improves our understanding of the trend of viral evolution in terms of viral infectivity, virulence or the capability of immune escape, which remains further validated by more future studies and statistical data. [ABSTRACT FROM AUTHOR]

Coupling electrooxidation of 2,5-bis(hydroxymethyl)furan (BHMFOR) with electroreduction of 5-hydroxymethylfurfural (HMFRR) might be a feasible approach towards the sustainable synthesis of value-added chemicals. Rational design of efficient and durable catalysts is crucial to this novel strategy. Herein, we demonstrate that the NiCo phosphide (NiCoP) nanosheet could be anodically reconstructed into a hydroxide-modified metaphosphate nanosheet (i.e., NiCoPi/Oi). The NiCoPi/Oi exhibits excellent BHMFOR performance with a low onset potential of 1.23 VRHE to yield 2,5-furandicarboxylic acid (FDCA) with nearly quantitative faradaic efficiency (FE), high selectivity (99%) and robust stability (for 10 cycles). A series of in situ spectroscopic analyses reveal dynamic cycles of NiOOH/Ni(OH)2 on the catalyst surface under the BHMFOR conditions, verifying an indirect oxidation pathway. As demonstrated by density functional theory (DFT) calculations, benefiting from the synergistic effect of heterostructures, the NiCoPi/Ni(OH)2 can enhance the adsorption of BHMF, hence promoting the BHMFOR through the indirect pathway. Furthermore, an electrode pair of NiCoP//NiCoPi/Oi is employed for the electrolysis of HMFRR/BHMFOR with graded electrolytes, fulfilling the concurrent synthesis of BHMF and FDCA with a combined FE of 134%. Our work thus provides new insights into catalyst design for biomass upgrading as well as a sustainable strategy for an overall conversion from HMF to FDCA. [ABSTRACT FROM AUTHOR]

The fatigue test of wind turbine blade is an important means to verify the fatigue life of wind turbine blade. This paper analyses the problems existing in the fatigue test of wind turbine blade, focuses on the excitation mode, the relationship between excitation amplitude and vibration frequency and the vibration principle, and puts forward feasible solutions in practical operation.

Nickel-based non-noble materials have been widely used as catalysts for a variety of electrosynthesis reactions due to their low cost and tunable surface properties. However, few of them perform well for the 5-hydroxymethylfurfural (HMF) oxidation reaction (HMFOR) due to their weak adsorption capacity for low-concentration reactants. In this work, Ox-NiCuOz derived from mixed metal oxide (NiCuOz) via anodic reconstruction is employed for the HMFOR, which remarkably outperforms Ox-NiCu(OH)z derived from NiCu-hydroxide (NiCu(OH)z). A series of ex/in situ investigations and theoretical calculations reveal that the adsorptions of HMF and intermediates are enhanced on the low-coordinated surface sites of Ox-NiCuOz, which facilitates the dynamic NiII/NiIII transformation and hence boosts the HMFOR. In addition, Red-NiCuOz derived via cathodic reconstruction is employed for the HMF reduction reaction (HMFRR). As a result, a paired HMFOR/HMFRR electrolysis is conducted using Ox-NiCuOz//Red-NiCuOz as the electrode pair, simultaneously yielding value-added products of 2,5-furandicarboxylic acid (FDCA) and 2,5-bishydroxymethylfuran (BHMF) with a combined faradaic efficiency (FE) of nearly 150% at 2 V. This study provides not only a guideline for non-noble catalyst design towards organic electrosynthesis, but also a rational scenario of paired electrolysis for highly efficient biomass utilization. [ABSTRACT FROM AUTHOR]

Electro-reduction of nitrate to ammonia (e-NRA) has been considered as a facile and promising approach to eliminate nitrate pollution and produce ammonia (NH3) under ambient conditions. Nevertheless, in recent state-of-the-art studies, high faradaic efficiency towards NH3 (FENH3) was usually achieved with a very negative working potential (vs. RHE) or high overpotential, which causes not only low cost-efficiency but also structural degradation in electrocatalysts. In this work, we utilize the strategy of in situ electrochemical reconstruction to develop a highly efficient and durable electrocatalyst Ru&Cu/Cu2O (denoted as i-Cu5Ru1Ox) towards alkaline e-NRA. As a result, highly selective production of NH3 can be achieved with an optimal FENH3 of around 95% even at a positive working potential of 0.1 V (vs. RHE) or a small overpotential of 0.59 V. The catalyst shows no obvious degradation after consecutive e-NRA for 10 h. In addition, density functional theory (DFT) computations reveal that the excellent catalytic performance of Ru&Cu/Cu2O could be attributed to the synergy of the Cu/Ru dual-site, which results in significantly enhanced adsorption of NO3− ion and a more favorable proton supply for the hydrogenation during e-NRA. This work thus highlights the importance of dual-site synergy towards the electrochemical process with multiple elementary steps. [ABSTRACT FROM AUTHOR]

Green hydrogen (H2) is an import energy carrier due to the zero-carbon emission in the energy cycle. Nevertheless, green H2 production based on electrolyzer and photovoltaics (EZ/PV) remains limited due to the highly pH-dependant and energy exhausting overall water splitting. Herein, we report a series of Ru-nanocluster-modified mesoporous nanospheres (Rux@mONC) as pH-universal electrocatalysts towards both hydrogen evolution reaction (HER) and hydrazine oxidation reaction (HzOR). The optimal catalyst Ru20@mONC realizes remarkable catalytic activity and stability towards both HER and HzOR regardless of electrolytes. As a result, the electrode pair of Ru20@mONC//Ru20@mONC requires low cell-potentials of 39/429, 405/926, and 164/1,141 mV to achieve the current density of 10/100 mA·cm−2, as well as the long-term stability for HzOR assisted electrochemical water splitting in alkaline, acidic, and neutral media, respectively. Those performances are more promising compared to the state-of-the-art electrocatalysts so far reported. A proof-of-concept test demonstrates an efficient production of green H2 powered by a single-junction silicon solar cell, which may inspire the use of a cost-effective EZ/PV system. Furthermore, a combined spectroscopic and theoretical study verifies the formation of abundant Ru/NC heterointerfaces in Ru20@mONC, which not only contributes to the balancing of H* adsorption/desorption in HER but also facilitates the *N2H2 dehydrogenation in HzOR. [ABSTRACT FROM AUTHOR]

Graphite carbons have been widely used as catalyst support due to their low‐cost, tunable porous structure, high electrical conductivity, and good resistance to harsh conditions. To date, various defect engineerings have been adopted to enhance the cohesion between graphite carbons and metallic nanocatalysts. Nevertheless, the modification of carbon basal plane has been less explored. In this work, a dual modification strategy is developed to achieve novel carbon support (denoted as NCf) incorporating both C60 units and trace N‐defects. Benefiting from the dual anchoring modes (Ru–C and Ru–N–C), ultrafine ruthenium (Ru) nanoclusters (average size: 2.26 ± 0.38 nm) can be well‐dispersed and robustly anchored on the NCf support. The optimal Ru0.013@NCf catalyst exhibits decent catalytic activities and long‐term stabilities toward both alkaline hydrogen evolution reaction (HER) and aromatic nitroreduction (ANR), outperforming the individually modified counterparts. Computational studies suggest that introducing both C60 and N‐defects into carbon support leads to electron‐deficient Ru nanocluster, which is critical for not only HER but also ANR. This work thus provides a new guideline for rational design of advanced carbon supported nanocatalysts for multipurpose applications. [ABSTRACT FROM AUTHOR]

Unmanned aerial vehicles (UAVs) have emerged as a promising candidate solution for data collection of large-scale wireless sensor networks (WSNs). In this paper, we investigate a UAV-aided WSN, where cluster heads (CHs) receive data from their member nodes, and a UAV is dispatched to collect data from CHs. We aim to minimize the total energy consumption of the UAV-WSN system in a complete round of data collection. Toward this end, we formulate the energy consumption minimization problem as a constrained combinatorial optimization problem by jointly selecting CHs from clusters and planning the UAV's visiting order to the selected CHs. The formulated energy consumption minimization problem is NP-hard, and hence, hard to solve optimally. To tackle this challenge, we propose a novel deep reinforcement learning (DRL) technique, pointer network-A* (Ptr-A*), which can efficiently learn the UAV trajectory policy for minimizing the energy consumption. The UAV's start point and the WSN with a set of pre-determined clusters are fed into the Ptr-A*, and the Ptr-A* outputs a group of CHs and the visiting order of CHs, i.e., the UAV's trajectory. The parameters of the Ptr-A* are trained on small-scale clusters problem instances for faster training by using the actor-critic algorithm in an unsupervised manner. Simulation results show that the trained models based on 20-clusters and 40-clusters have a good generalization ability to solve the UAV's trajectory planning problem in WSNs with different numbers of clusters, without retraining the models. Furthermore, the results show that our proposed DRL algorithm outperforms two baseline techniques. [ABSTRACT FROM AUTHOR]

This paper investigates the entire process of 4D printing of shape memory alloys (SMAs), characterized by pre-programming of the future responsive shape of a deformable structure during its 3D forming. Taking an inchworm-inspired crawling robot as an application case, we propose a system prototype composed of two deformable SMA structures, i.e. a curved sheet and a spring coil. From the behavioral synergism of these two antagonistically configured structures, the initial and responsive shapes of each binary structure were collaboratively designed. The feature shapes of different structures were then pairwise combined to generate the robot's gait, which was realized through the alternating activations of the two components. We also investigated the processing strategy and methods of the presented structures with small feature sizes and unique configurations, based on the optimal 3D printing process of selective laser melting of nickel–titanium alloys. The experimental results verified the design expectations and demonstrated the performance stability of the SMA structures under multiple testing cycles. This research confirmed the possible use of hard materials to create customized smart structures with high levels of flexibility and deformation control, providing new ideas for further development of intelligent, flexible robots. [ABSTRACT FROM AUTHOR]

This article presents a soft crawling robot prototype with a simple architecture inspired by inchworms. The robot functionally integrates the torso (body) and feet in a monolithic curved structure that only needs a single shape memory alloy coil and differential friction to actuate it. A novel foot configuration is proposed, which makes the two feet, with an anti-symmetrical friction layout, can be alternately anchored, to match the contraction–recovery sequence of the body adaptively. Based on the antagonistic configuration between the shape memory alloy actuator and the elastic body, a vertically auxiliary spring was adopted to enhance the interaction mechanism. Force and kinematic analysis was undertaken, focusing on the parametric design of the special foot configuration. A miniature robot prototype was then 3D-printed (54 mm in length and 9.77 g in weight), using tailored thermoplastic polyurethane elastomer as the body material. A series of experimental tests and evaluations were carried out to assess its performance under different conditions. The results demonstrated that under appropriate actuation conditions, the compact robot prototype could accomplish a relative speed of 0.024 BL/s (with a stride length equivalent to 27% of its body length) and bear a load over five times to its own weight. [ABSTRACT FROM AUTHOR]

For water electrolysis and metal–air batteries, the rational design and preparation of highly efficient and environmentally friendly catalysts for the oxygen evolution reaction (OER) is urgently required. Here, abundant Co3O4/MnCO3 heterointerfaces supported on Ni foam are facilely fabricated via an energy-efficient hydrothermal annealing method. The heterostructure and cactus-like hierarchical structure enable the sample to have prominent OER activity and excellent stability. Specifically, the electrocatalyst requires only a low overpotential of 273 mV at a current density of 10 mA cm−2 and has a small Tafel slope of 62.06 mV dec−1 in 1 M KOH electrolyte; these results are superior to most non-noble metal based OER catalysts reported to date. Our work provides a novel perspective for the rational design and synthesis of low-cost electrocatalysts, especially in the selection of other low-budget compounds for interface engineering. [ABSTRACT FROM AUTHOR]

The mechanical properties of cells are closely related to their physiological functions and states. Analyzing and measuring these properties are beneficial to understanding cell mechanisms. However, most measurement methods only involve the unidirectional analysis of cellular mechanical properties and thus result in the incomplete measurement of these properties. In this study, a microfluidic platform was established, and an innovative microfluidic chip was designed to measure the multiangle cellular mechanical properties by using dielectrophoresis (DEP) force. Three unsymmetrical indium tin oxide (ITO) microelectrodes were designed and combined with the microfluidic chip, which were utilized to generate DEP force and stretch cell from different angles. A series of experiments was performed to measure and analyze the multiangle mechanical properties of red blood cells of mice. This work provided a new tool for the comprehensive and accurate measurement of multiangle cellular mechanical properties. The results may contribute to the exploration of the internal physiological structures of cells and the building of accurate cell models. [ABSTRACT FROM AUTHOR]

• Zr-doping Co 3 O 4 electrocatalysts were fabricated on nickel foam. • Zr-doping Co 3 O 4 weave-like nanoarray exhibits excellent alkaline OER activity. • The free energy of potential rate-determining step is reduced. • Morphology and electronic structure of Co 3 O 4 were optimized by Zr doping. • The design of the experiment can be guided and predicted via DFT calculations. Zr-doping Co 3 O 4 weave-like nanoarray as an efficient OER catalyst was designed under the guidance of DFT calculations. Zr doping in Co 3 O 4 can accelerate potential rate-determining step, regulate electronic structure and morphology, therefore, boost OER activity. [Display omitted] It is urgently crucial to design high-performance and low-cost electrocatalysis for oxygen evolution reaction (OER) toward associated renewable energy systems. Herein, we reported that a certain amount of Zirconium doping in Co 3 O 4 can regulate the electronic structure and morphology, therefore, boost the OER electrocatalytic performance. Zr doped Co 3 O 4 demonstrates more excellent OER activity than pure Co 3 O 4 , as confirmed by density functional theory (DFT) calculations and experimental results, where the acceleration of potential rate-determining step and the improvement of conductivity are attributed to the introduction of Zr-dopants. Specifically, the as-synthesized 3D Zr-Co 3 O 4 /NF exhibits prominent OER activity with low overpotential 307 mV to drive current density of 20 mA cm−2, modest Tafel slope of 99 mV dec−1 and robust stability in 1 M KOH electrolyte. Our work reveals a novel approach to disclose Zr as a feasible dopant to optimize electronic structure and OER catalytic performance of metal oxides, and also proves the guiding role of DFT calculations for reasonable preparation of high-efficiency OER catalysts. [ABSTRACT FROM AUTHOR]