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Addressing the sluggish kinetics in the alkaline hydrogen oxidation reaction (HOR) is a pivotal yet challenging step toward the commercialization of anion-exchange membrane fuel cells (AEMFCs). Here, we have successfully immobilized indium (In) atoms in an orderly fashion into platinum (Pt) nanoparticles supported by reduced graphene oxide (denoted as O-Pt3In/rGO), significantly enhancing alkaline HOR kinetics. We have revealed that the ordered atomic matrix enables uniform and optimized hydrogen binding energy (HBE), hydroxyl binding energy (OHBE), and carbon monoxide binding energy (COBE) across the catalyst. With a mass activity of 2.3066 A mg–1at an overpotential of 50 mV, over 10 times greater than that of Pt/C, the catalyst also demonstrates admirable CO resistance and stability. Importantly, the AEMFC implementing this catalyst as the anode catalyst has achieved an impressive power output compared to Pt/C. This work not only highlights the significance of constructing ordered oxophilic sites for alkaline HOR but also sheds light on the design of well-structured catalysts for energy conversion.

A strain engineering strategy is crucial for designing a high-performance catalyst. However, how to control the strain in metastable phase two-dimensional (2D) materials is technically challenging due to their nanoscale sizes. Here, we report that cerium dioxide (CeO2) is an ideal loading material for tuning the in-plane strain in 2D metastable 1T-phase IrO2(1T-IrO2) via an in situ growth method. Surprisingly, 5% CeO2loaded 1T-IrO2with 8% compressive strain achieves an overpotential of 194 mV at 10 mA cm–2in a three-electrode system. It also retained a high current density of 900 mA cm–2at a cell voltage of 1.8 V for a 400 h stability test in the proton-exchange membrane device. More importantly, the Fourier transform infrared measurements and density functional theory calculation reveal that the CeO2induced strained 1T-IrO2directly undergo the *O–*O radical coupling mechanism for O2generation, totally different from the traditional adsorbate evolution mechanism in pure 1T-IrO2. These findings illustrate the important role of strain engineering in paving up an optimal catalytic pathway in order to achieve robust electrochemical performance.

Low tumor immunogenicity, immunosuppressive tumor microenvironment, and bacterial infections have emerged as significant challenges in postsurgical immunotherapy and skin regeneration for preventing melanoma recurrence. Herein, an immunotherapeutic hydrogel booster (GelMA-CJCNPs) was developed to prevent postoperative tumor recurrence and promote wound healing by incorporating ternary carrier-free nanoparticles (CJCNPs) containing chlorine e6 (Ce6), a BRD4 inhibitor (JQ1), and a glutaminase inhibitor (C968) into methacrylic anhydride-modified gelatin (GelMA) dressings. GelMA-CJCNPs reduced glutathione production by inhibiting glutamine metabolism, thereby preventing the destruction of reactive oxygen species generated by photodynamic therapy, which could amplify oxidative stress to induce severe cell death and enhance immunogenic cell death. In addition, GelMA-CJCNPs reduced M2-type tumor-associated macrophage polarization by blocking glutamine metabolism to reverse the immunosuppressive tumor microenvironment, recruiting more tumor-infiltrating T lymphocytes. GelMA-CJCNPs also downregulated IFN-γ-induced expression of programmed cell death ligand 1 to mitigate acquired immune resistance. Benefiting from the amplified systemic antitumor immunity, GelMA-CJCNPs markedly inhibited the growth of both primary and distant tumors. Moreover, GelMA-CJCNPs demonstrated satisfactory photodynamic antibacterial effects against Staphylococcus aureusinfections, thereby promoting postsurgical wound healing. Hence, this immunotherapeutic hydrogel booster, as a facile and effective postoperative adjuvant, possesses a promising potential for inhibiting tumor recurrence and accelerating skin regeneration.

Clarifying the structure–reactivity relationship of non-noble-metal electrocatalysts is one of the decisive factors for the practical application of water electrolysis. In this field, the anodic oxygen evolution reaction (OER) with a sluggish kinetic process has become a huge challenge for large-scale production of high-purity hydrogen. Here we synthesize a layered quasi-nevskite metastable-phase cobalt oxide (LQNMP-Co2O3) nanosheet via a simple molten alkali synthesis strategy. The unit-cell parameters of LQNMP-Co2O3are determined to be a= b= 2.81 Å and c= 6.89 Å with a space group of P3̅m1 (No. 164). The electrochemical results show that the LQNMP-Co2O3electrocatalyst enables delivering an ultralow overpotential of 266 mV at a current density of 10 mA cmgeo–2with excellent durability. The operandoXANES and EXAFS analyses clearly reveal the origin of the OER activity and the electrochemical stability of the LQNMP-Co2O3electrocatalyst. Density functional theory (DFT) simulations show that the energy barrier of the rate-determining step (RDS) (from *O to *OOH) is significantly reduced on the LQNMP-Co2O3electrocatalyst by comparing with simulated monolayered CoO2(M-CoO2).

Hyperspectral remote sensing images exhibit fine spectral curves, but they are also susceptible to spectral variations caused by factors such as cloud and haze. It is evident that these issues become more pronounced when there is a limited number of labeled samples available. Thus, a full range feature extraction network (FRFENet) based on quality–quantity-balance sample enhancement is proposed for hyperspectral image classification (HSIC). First, the full-range feature extraction method combines local-range, short-range, and long-range spatial–spectral features to address spectral variability and ensure accurate feature extraction, particularly in scenarios with limited labeled samples. Furthermore, the approach of balancing quality and quantity for pseudolabeled samples allows for an increased number of pseudolabels while maintaining their quality, effectively leveraging unlabeled samples. In addition, the utilization of superpixel region homogeneity directly contributes to an expanded training sample set, resulting in improved classification performance of the algorithm. Experiments on three hyperspectral image (HSI) encompass datasets indicate that the FRFENet can obtain better classification performance when compared with the other ten state-of-the-art methods.

ABSTRACT A series of innovative connections with the different combinations of steel plates and screws was developed for timber-concrete composite (TCC) system in this paper. Several groups have introduced vulcanized [...]

Two-dimensional (2D) van der Waals single crystals with long-range magnetic order are the precondition and urgent task for developing a 2D spintronics device. In contrast to graphene and transition metal dichalcogenides, the study of 2D single-crystal metal oxides with intrinsic ferromagnetic properties remains a huge challenge. Here, we report a large-size trigonal single-crystal rhodium oxide (SC-Tri-RhO2), with crystal parameters of a= b= 3.074 Å, c= 6.116 Å, and a space group of P3̅m1 (164), exhibiting strong ferromagnetism (FM) at a rather high temperature. Furthermore, theoretical calculations suggest that the ferromagnetism in SC-Tri-RhO2originates from spin splitting near the Fermi level, and the total magnetic moment is contributed mainly by the Rh atom.

• A novel hydrogel with biological activity and photothermal effect was synthesized. • The hydrogel can exert anti-tumor and antibacterial effect through photothermal effect. • The hydrogel can effectively promote the repair of articular cartilage defects in vivo. Following operative treatment of chondrosarcoma, post-surgery tissue reconstruction may be confronted with daunting challenges, including the delayed self-repair of defective tissue, tumor recurrence, and bacterial infection. To overcome these challenges, a methacrylic anhydride (MA) modified sericin (SerMA) solution mixed with procyanidins (PC) loaded polydopamine (PDA) modified ZIF-8 (PC@ZIF-8@PDA) nanoparticles to form a multifunctional PC@ZIF-8@PDA/SerMA hydrogel after exposure under blue light. Hydrogel products with pre-designed shapes were printed out by using the SerMA solution carrying PC@ZIF-8@PDA nanoparticles and chondrocytes, indicating that PC@ZIF-8@PDA/SerMA hydrogels with personalized shapes can be fabricated via 3D printing. Photocrosslinked PC@ZIF-8@PDA/SerMA hydrogel is able to kill chondrosarcoma cells and bacteria, like Staphylococcus aureus (S. aureus) , and Escherichia coli (E. coli) , by its photothermal activity combined with near-infrared radiation (NIR). The PC@ZIF-8@PDA/SerMA hydrogel exhibited an antioxidative activity and a good biocompatibility and was easily monitored by its florescent and photoacoustic properties. Rabbit articular cartilage defects were efficiently repaired by PC@ZIF-8@PDA/SerMA hydrogels with encapsulated corresponding autologous chondrocytes, and mice skin burning wounds were swiftly regenerated by applying this hydrogel. Hence, the PC@ZIF-8@PDA/SerMA hydrogel can be potentially applied to the clinic treatment of chondrosarcoma and tissue defect repair after chondrosarcoma resection due to its multifunction in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

Idiopathic pulmonary fibrosis (IPF), a progressive lung disease characterized by irreversible lung dysfunction caused by fibroblast proliferation and excessive collagen deposition, is the result of persistent chronic inflammation of the lung parenchyma. Although the pathogenesis is not fully understood, the role of immune mechanisms such as innate immune response, adaptive immunity and immune regulation, and cytokines in the pathophysiological mechanism of pulmonary fibrosis have been gradually recognized. There are currently limited drugs available to treat IPF, and long-term use of these drugs may have many adverse effects. With the elucidation of the underlying immunological pathogenesis, the development of more valuable drugs targeting the immune system becomes possible. This review introduces the immunological pathogenesis of pulmonary fibrosis and the emerging drugs targeting the immune system in recent years, aiming to provide insights into the mechanism and treatment direction of pulmonary fibrosis.

Electrochemical water splitting provides a green pathway for hydrogen generation, while iridium oxide (IrO2) is almost the only stable anode catalyst for acidic media. Yet, it is still a huge challenge to develop an efficient IrO2catalyst. Here, we demonstrate a microwave-assisted mechano-thermal method that achieves a new 3R phase IrO2. This 3R-IrO2achieves an ultralow overpotential of 188 mV at the current density of 10 mA cmgeo−2and a notably high turnover frequency of 5.7 sUPD−1at 1.50 V versus reversible hydrogen electrode. It also endures limited decay under the current density of 10 mA cmgeo−2for 511 h prolong test in acidic electrolyte. The new active sites of the edge-sharing structure in 3R-IrO2and the fast proton transportation along interlayers and intralayers through iridium vacancies contribute to the extraordinary acidic oxygen evolution reaction (OER) activity and stability. This work highlights the great potential of new metastable materials toward advanced electrocatalysis.

To study the effects of social stress (CS) and social stress combined with high-fat diet on fat mobilization as a candidate mechanism for the induction or aggravation of non-alcoholic fatty liver disease (NAFLD).

In recent years, energy efficiency has become an important topic, especially in the field of ultra-dense networks (UDNs). In this area, cell-association bias adjustment and small cell on/off are proposed to enhance the performance of energy efficiency in UDNs. This is done by changing the cell association relationship and turning off the extra small cells that have no users. However, the variety of cell association relationships and the switching on/off of the small cells may deteriorate some users’ data rates, leading to nonconformance to the users’ data rate requirement. Considering the discreteness and non-convexity of the energy efficiency optimization problem and the coupled relationship between cell association and scheduling during the optimization process, it is difficult to achieve an optimal cell-association bias. In this study, we optimize the network energy efficiency by adjusting the cell-association bias of small cells while satisfying the users’ data rate requirement. We propose an energy-efficient centralized Gibbs sampling based cell-association bias adjustment (CGSCA) algorithm. In CGSCA, global information such as channel state information, cell association information, and network load information need to be collected. Then, considering the overhead of the messages that are exchanged and the implementation complexity of CGSCA to obtain the global information in UDNs, we propose an energy-efficient distributed Gibbs sampling based cell-association bias adjustment (DGSCA) algorithm with a lower message-exchange overhead and implementation complexity. Using DGSCA, we derive the updated formulas for calculating the number of users in a cell and the users’ SINR. We analyze the implementation complexities (e.g., computation complexity and communication com- plexity) of the proposed two algorithms and other existing algorithms. We perform simulations, and the results show that CGSCA and DGSCA have faster convergence speed, as well as a higher performance gain of the energy efficiency and throughput compared to other existing algorithms. In addition, we analyze the importance of the users’ data rate constraint in optimizing the energy efficiency, and we compare the energy efficiency performance of different algorithms with different number of small cells. Then, we present the number of sleeping small cells as the number of small cells increases.

Tuning the local spin configurations of single-atom electrocatalysts holds enormous promise in boosting the oxygen reduction reaction (ORR), but still fills with challenging of lacking efficient means. Herein, a binary-atom catalyst (PtCo-NC) consisting of atomically dispersed Pt and Co on nitrogen doped carbon is rationally designed and synthesized by a mechano-thermal milling method. Theoretical calculations reveal that the introduction of atomically dispersed Co results in spin polarization of adjacent Pt atoms, which optimizes the absorption energy and lowers the energy barrier of the rate-determining step, thus accelerating oxygen catalyzed reaction kinetics for PtCo-NC. As a consequence, the constructed PtCo-NC possesses an outstanding ORR performance with a positive half-wave potential (0.85 V), large kinetic current density (83.3 mA cm−2at 0.8 V), low Tafel slope (85 mV dec−1) and robust cyclic stability (more than 90% retention after 170 h in alkaline media). As the cathodic catalyst, the zinc-air battery driven by PtCo-NC delivers the maximum power density (204 mW cm−2), excellent rate capacity and remarkable durability. The present work may provide new insight into boosting oxygen reduction reaction activity, leading the exploration toward highly efficient catalysts for renewable energy storage and conversion systems.

Electrocatalytic water splitting is a desirable and sustainable strategy for hydrogen production yet still faces challenges due to the sluggish kinetics and rapid deactivation of catalysts in the oxygen evolution process. Herein, we utilized the metal-catalyzed growth technology and phosphating process to fabricate self-supported electrodes (CoxPy@CNT-CC) composed of carbon nanotube (CNT) arrays grown on carbon cloth (CC); thereinto, cobalt-based phosphide nanoparticles (CoxPy) are uniformly encapsulated in the cavity of the CNTs. After further optimization, when the nanoparticles are in the composite phase (CoP2/Co2P), CoP2/Co2P@CNT-CC served as catalytic electrodes with the highest activity and stability for electrocatalytic water splitting in an alkaline medium (1.0 M KOH). The as-prepared CoP2/Co2P@CNT-CC integrates the advantages of the abundant active sites and confinement effect of CNTs, imparting promising electrocatalytic activities and stability in catalyzing both hydrogen evolution reaction and oxygen evolution reaction. Remarkably, electrocatalytic water splitting cells assembled using CoP2/Co2P@CNT-CC electrodes as the cathode and anode, respectively, require a cell voltage of 1.55 V at 10 mA cm–2, which is lower than that of the commercially noble Pt/C/CC and RuO2/CC catalyst couple (1.68 V). Besides, a CoP2/Co2P@CNT-CC||CoP2/Co2P@CNT-CC system shows outstanding durability for a period of 100 h at 10 mA cm–2. This work may provide new ideas for designing bifunctional electrocatalysts for applications in electrocatalytic water splitting.

Carbon dioxide electrochemical reduction (CO2RR) has been recognized as an efficient way to mitigate CO2emissions and alleviate the pressure on global warming and associated environmental consequences. Gold (Au) is reported as stable and active electrocatalysts to convert CO2to CO at low overpotential due to its moderate adsorption strength of *COOH and *CO. The request for improved catalytic performance, however, is motivated by current unsatisfied catalytic selectivity because of the side hydrogen evolution reaction. In this context, the design of Au based binary catalysts that can boost CO selectivity is of great interest. In the present work, we report that Au nanoparticles can be feasibly dispersed and anchored on silicon nanowires to form Au-Si binary nanomaterials. The Au-Si may stably drive CO2RR with a CO Faraday efficiency of 95.6% at −0.6 V vs.RHE in 0.5 mol/L KHCO3solution. Such selectivity outperforms Au particles by up to 61%. Controlled experiments illustrate that such catalytic enhancement can chiefly be ascribed to electronic effects of binary catalysts. Theoretical calculations reveal that spontaneously produced silicon oxide may not only inhibit hydrogen evolution reaction, but also stabilize the key intermediate *COOH in CO formation.

We study in this paper the exponential time differencing (ETD) schemes and their modifications via complex contour integrations for the numerical solutions of parabolic type equations. We illustrate that the contour integration shares an added advantage of improving the stability of the time integration. In addition, we demonstrate the effectiveness of the ETD type schemes through the numerical solution of a typical problem in phase field modeling and through the comparisons with other existing methods.

A new p‐tert‐butyl­thia­calix­[4]­arene derivative, C72H68N4O4S4·2CH2Cl2, has been synthesized and is comprised of one tetra‐p‐tert‐butyltetrakis(2‐cyano­benzyl­oxy)­tetra­thia­calix­[4]arene and two di­chloro­methane mol­ecules. The calix­[4]­arene mol­ecule is centrosymmetric and adopts an unusual 1,2‐alternate conformation viaπ–π interactions between adjacent cyano­phenyl rings on the lower rim of the parent thia­calix­[4]­arene system.