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Metal foam material, which serves as an alternative replacement of the conventional flow distributor of proton exchange membrane (PEM) fuel cell, has been attracting much attention over last few decades. In this work, three-dimensional modeling work for PEM fuel cell containing metal foam as cathode flow distributor has been carried out. The fuel cell performance and operating characteristics of metal foam flow field and conventional parallel flow channel have been compared and discussed. The cell performance has been reasonably validated based on the corresponding experimental tests conducted in this study. The superior performance of PEM fuel cell with metal foam as cathode flow field benefits a lot from the uniform gas flow. The porous metal foam material provides more pathways for the water delivery at the interface of metal foam flow field and gas diffusion layer (GDL), accelerating water removal capability of cathode. Because of the significant oxygen transfer loss in diffusion limited parallel channel, the operation of PEM fuel cell with parallel channel is found to be more sensitive to cathode humidification and oxygen supply at inlet. Due to the more uniform and effective electron transport though the porous electrode, it is possible to use thinner GDL in metal foam PEM fuel cell. It is expected that this study could give a good baseline of operating behavior of PEM fuel cell with metal foam flow distributor.

With the rapid growth and development of proton-exchange membrane fuel cell (PEMFC) technology, there has been increasing demand for clean and sustainable global energy applications. Of the many device-level and infrastructure challenges that need to be overcome before wide commercialization can be realized, one of the most critical ones is increasing the PEMFC power density, and ambitious goals have been proposed globally. For example, the short- and long-term power density goals of Japan’s New Energy and Industrial Technology Development Organization are 6 kilowatts per litre by 2030 and 9 kilowatts per litre by 2040, respectively. To this end, here we propose technical development directions for next-generation high-power-density PEMFCs. We present the latest ideas for improvements in the membrane electrode assembly and its components with regard to water and thermal management and materials. These concepts are expected to be implemented in next-generation PEMFCs to achieve high power density. This Perspective reviews the recent technical developments in the components of the fuel cell stack in proton-exchange membrane fuel cell vehicles and outlines the road towards large-scale commercialization of such vehicles.

A study was conducted to analyze the deformation mechanism of strongly weathered quartz schist in the Daliangshan Tunnel, located in the western Transverse Mountain area. A large deformation problem was experienced during the tunnel construction. To mitigate this problem, a support system was designed incorporating negative Poisson ratio (NPR) anchor cables with negative Poisson ratio effect. Physical model experiments, field experiments, and numerical simulation experiments were conducted to investigate the compensation mechanical behavior of NPR anchor cables. The large deformations of soft rocks in the Daliangshan Tunnel are caused by a high ground stress, a high degree of joint fracture development, and a high degree of surrounding rock fragmentation. A compensation mechanics support system combining long and short NPR anchor cables was suggested to provide sufficient counter-support force (approximately 350 kN) for the surrounding rock inside the tunnel. Comparing the NPR anchor cable support system with the original support system used in the Daliangshan tunnel showed that an NPR anchor cable support system, combining cables of 6.3 m and 10.3 m in length, effectively prevented convergence of surrounding rock deformation, and the integrated settlement convergence value remained below 300 mm. This study provides an effective scientific basis for resolving large deformation problems in deeply buried soft rocks in western transverse mountain areas.

The campaign life of blast furnace （BF） hearths has become the limiting factor for safety and high efficiency production of modern BFs. However, the early warning mechanism of hearth security has not been clear. In this article, based on heat transfer calculations, heat flux and erosion monitoring, the features of heat flux and erosion were analyzed and compared among different types of hearths. The primary detecting elements, mathematical models, evaluating standards, and warning methods were discussed. A novel early warning mechanism with the three-level quantificational standards was proposed for BF hearth security.

Single-image dehazing suffers from severe information loss and the under-constraint problem. The lack of high-quality robust priors leads to limited generalization ability of existing dehazing methods in real-world scenarios. To tackle this challenge, we propose a simple but effective single-image dehazing network by fusing high-quality semantic priors extracted from Segment Anything Model 2 (SAM2) with different types of advanced convolutions, abbreviated SAM2-Dehaze, which follows the U-Net architecture and consists of five stages. Specifically, we first employ the superior semantic perception and cross-domain generalization capabilities of SAM2 to generate accurate structural semantic masks. Then, a dual-branch Semantic Prior Fusion Block is designed to enable deep collaboration between the structural semantic masks and hazy image features at each stage of the U-Net. Furthermore, to avoid the drawbacks of feature redundancy and neglect of high-frequency information in traditional convolution, we have designed a novel parallel detail-enhanced and compression convolution that combines the advantages of standard convolution, difference convolution, and reconstruction convolution to replace the traditional convolution at each stage of the U-Net. Finally, a Semantic Alignment Block is incorporated into the post-processing phase to ensure semantic consistency and visual naturalness in the final dehazed result. Extensive quantitative and qualitative experiments demonstrate that SAM2-Dehaze outperforms existing dehazing methods on several synthetic and real-world foggy-image benchmarks, and exhibits excellent generalization ability.

Blood-based protein biomarkers have recently shown as simpler diagnostic modalities for colorectal cancer, while their association with clinical pathological characteristics is largely unknown. In this study, we not only examined the sensitivity and reliability of single/multiple serum markers for diagnosis, but also assessed their connection with pathological parameters from a total of 279 colorectal cancer patients. Our study shown that glycoprotein carcinoembryonic antigen (CEA) owns the highest sensitivity among single marker in the order of CEA > cancer antigen 72-4 (CA72-4) > cancer antigen 19-9 9 (CA19-9) > ferritin > cancer antigen 125 (CA125), while the most sensitive combined-markers for two to five were: CEA + CA72-4; CEA + CA72-4 + CA125; CEA + CA19-9 + CA72-4 + CA125; and CEA + CA19-9 + CA72-4 + CA125 + ferritin, respectively. We also demonstrated that patients who had positive preoperative serum CEA, CA19-9, or CA72-4 were more likely with lymph node invasion, positive CA125 were prone to have vascular invasion, and positive CEA or CA125 were correlated with perineural invasion. In addition, positive CA19-9, CA72-4, or CA125 was associated with poorly differentiated tumor, while CEA, CA19-9, CA72-4, CA125 levels were positively correlated with pathological tumor-node-metastasis stages. We here conclude that combined serum markers can be used to not only diagnose colorectal cancer, but also appraise the tumor status for guiding treatment, evaluation of curative effect, and prognosis of patients.

Topological soft matter systems rely on controllable defect structures to encode functionality, yet robust, large-scale, and reconfigurable manipulation strategies remain elusive. Here we present a versatile acoustic platform for dynamic control of liquid crystal defect arrays via engineered topological wavefields. By coherently superimposing surface acoustic waves, we generate spatially structured potential landscapes and acoustic streaming vortices that interact with the molecular orientation field of liquid crystals, enabling dynamic reconfiguration of topological defects. Tuning the acoustic parameter space allows precise modulation of defect density, symmetry, morphology, and spatial positioning. A theoretical framework based on Ginzburg-Landau modeling and free energy minimization captures the formation of vortex-induced instabilities and associated topological textures. The platform operates across diverse liquid crystal compositions, demonstrating material generality. This acoustically driven approach offers a scalable strategy for programmable topological structure in soft matter, with potential applications in reconfigurable photonic devices and active material systems. Topological defects can be used to encode functionalities in soft matter systems. Here, authors dynamically reconfigure an acoustic lattice to create programmable topological defect arrays. The resulting velocity fields and steady acoustic streaming realign the director, enabling reversible control of defect properties and their translation.

Background Carbapenem-resistant and hypervirulent Klebsiella pneumoniae (CR-hvKP) caused infections of high mortality and brought a serious impact on public health. This study aims to evaluate the epidemiology, resistance and virulence characteristics of CR-hvKP and to identify potential drivers of cross-regional transmission in different regions of China, in order to provide a basis for developing targeted prevention measures. Methods Clinical K. pneumoniae strains were collected from Jiujiang and Nanchang in Jiangxi province between November 2021 to June 2022. Clinical data of patients (age, sex, source of infection, and diagnosis) were also gathered. We characterized these strains for their genetic relatedness using PFGE, antimicrobial and virulence plasmid structures using whole-genome sequencing, and toxicity using Galleria mellonella infection model. Results Among 609 strains, 45 (7.4%) CR-hvKP were identified, while the strains. isolated from Nanchang and Jiujiang accounted for 10.05% (36/358) and 3.59% (9/251). We observed that ST11-KL64 CR-hvKP had an overwhelming epidemic dominance in these two regions. Significant genetic diversity was identified among all ST11-KL64 CR-hvKP cross-regional transmission between Nanchang and Jiujiang and this diversity served as the primary driver of the dissemination of clonal groups. Virulence genes profile revealed that ST11-KL64 CR-hvKP might harbour incomplete pLVPK-like plasmids and primarily evolved from CRKP by acquiring the hypervirulence plasmid. We found the predominance of truncated-IncFIB/IncHI1B type virulence plasmids with a 25 kb fragment deletion that encoded iroBCDN clusters. Conclusion ST11-KL64 is the most cross-regional prevalent type CR-hvKPs in Jiangxi province, which mainly evolved from CRKPs by acquiring a truncated-IncHI1B/IncFIB virulence plasmid with the deletion of iroBCDN . Stricter surveillance and control measures are urgently needed to prevent the epidemic transmission of ST11-KL64 CR-hvKP.

Background Combination of chemotherapy and immune checkpoint inhibitor therapy has greatly improved the anticancer effect on multiple malignancies. However, the efficiency on triple-negative breast cancer (TNBC) is limited, since most patients bear “cold” tumors with low tumor immunogenicity. Doxorubicin (DOX), one of the most effective chemotherapy agents, can induce immunogenic cell death (ICD) and thus initiating immune response. Methods In this study, to maximize the ICD effect induced by DOX, chitosan and cell-penetrating peptide (R6F3)-modified nanoparticles (PNPs) loaded with ginsenoside Rg3 (Rg3) were fabricated using the self-assembly technique, followed by co-encapsulation with DOX based on thermo-sensitive hydrogel. Orthotopic tumor model and contralateral tumor model were established to observe the antitumor efficacy of the thermo-sensitive hydrogel combined with anti-PD-L1 immunotherapy, besides, the biocompatibility was also evaluated by histopathological. Results Rg3-PNPs strengthened the immunogenic cell death (ICD) effect induced by DOX. Moreover, the hydrogel co-loading Rg3-PNPs and DOX provoked stronger immune response in originally nonimmunogenic 4T1 tumors than DOX monotherapy. Following combination with PD-L1 blocking, substantial antitumor effect was achieved due to the recruitment of memory T cells and the decline of adaptive PD-L1 enrichment. Conclusion The hydrogel encapsulating DOX and highly permeable Rg3-PNPs provided an efficient strategy for remodeling immunosuppressive tumor microenvironment and converting immune “cold” 4T1 into “hot” tumors.

Mining-induced subsidence boundaries, i.e., the surface areas affected by underground mining, play an important role in surface damage assessment and illegal mining identification. Traditional boundary delineation methods rely on field surveys, which restrict their applicability in regions with limited ground observations. Interferometric Synthetic Aperture Radar (InSAR) technology provides a cost-effective and non-contact solution for delineating subsidence boundaries. However, existing InSAR-based methods for subsidence boundary delineation are susceptible to observation noise and other deformation sources, which reduce the accuracy of boundary identification. To this end, this study proposes a novel method for delineating mining-induced subsidence boundaries by integrating both the magnitude and direction of InSAR-derived deformation gradients, referred to as DMSB-DG. First, time-series line-of-sight (LOS) deformation is obtained based on InSAR technology over mining areas. Then, the Roberts operator is employed to compute the magnitude and direction of the deformation gradients, which serve as the basis for boundary delineation. Finally, the ISODATA clustering algorithm is used, incorporating both the magnitude and direction of the deformation gradients as dual constraints to achieve accurate delineation of mining-affected boundaries. The combination of the two features effectively enhances the completeness and accuracy of boundary delineation. The performance of the proposed DMSB-DG method has been verified by simulation and field data. Specifically, compared with the adaptive mining subsidence boundary delimitation (ASBD) method, the proposed method achieved Kappa coefficients of 91.96% and 87.28%, representing improvements of 21.23% and 27.14% in two field tests, respectively. Furthermore, the influence of ascending and descending SAR images, as well as observational noise, on the performance of the proposed algorithm is also evaluated. The results demonstrate that the proposed method effectively suppresses InSAR noise and other interfering deformations, enabling high-precision delineation of mining impact boundaries.