As a typical form of weathering, cyclic wetting-drying treatment on host rock is commonly encountered in many applications of geotechnical engineering. How cyclic wetting-drying weathering affects ...the strength and deformation behavior of host rock is a topic worthy of comprehensively investigating. In this study, the influence of cyclic wetting-drying weathering on mechanical behavior of a medium-grained sandstone is experimentally investigated. The sandstone specimens are first subjected to different wetting-drying weathering cycles, and uniaxial compression tests and direct shear tests are then conducted on these prepared specimens. The results show that the water absorption of the rock monotonically increases with the increase of the number of wetting-drying cycle in the treatment. The strength and deformation properties (i.e., uniaxial compressive strength, Young's modulus, cohesion, and friction angle) are found to decrease with the increase of wetting-drying cycle in the treatment and the decrease gradually diminishes as the number of wetting-drying cycle becomes large. Upon failure of the rock specimen under both uniaxial compression and direct shear, the integrity is progressively weakened and more fragments can be observed as the number of wetting-drying cycle in the treatment gradually increases. The deterioration of rock strength and deformation properties is found to be mainly associated with the micro-cracks generated inside the rock in response to cyclic wetting-drying weathering. The data in this study provide useful guidance for long-term stability evaluation of engineering structures constructed under cyclic wetting-drying weathering condition.
•Cyclic wetting-drying weathering effect on rock behavior is experimentally studied.•Water absorption increase with increasing wetting-drying cycle in the treatment.•Strength and deformation parameters decrease with the increase of wetting-drying cycle.•Rock deterioration is mainly associated with micro-cracks generated inside the rock.
The propagation process of blasting vibration has always been a difficult problem affecting the stability of high slopes in open-pit mines. Taking the Jianshan Phosphorus Mine as the research ...background, combined with engineering geological investigation, field blasting test, blasting vibration monitoring, numerical simulation technology, and theoretical analysis, the three-dimensional dynamic stability of the adjacent high slope after blasting vibration was systematically studied. In our study, a small-diameter buffer shock-absorbing blasting technology near the slope was proposed, which greatly improved the production efficiency. Through regression analysis of a large amount of vibration test data, the law of blasting vibration propagation in Jianshan stope and Haifeng stope was obtained. In addition, by establishing four three-dimensional geomechanical numerical models, the slope's own frequency, damping characteristics, and dynamic response acceleration distribution after detonation were studied, respectively. On the other hand, under the action of Ei Centro wave with 8-degree seismic intensity, the maximum total acceleration and maximum total displacement of the slope were calculated and analyzed. Both the explosion unloading of the 8-degree earthquake and the Ei Centro wave simulation results showed that the high slope near the Jianshan Phosphorus Mine was generally in a stable state. Thus, this study can provide technical support and theoretical guidance for mine blasting.
•Proposes a Ray slack-based model drawing on polar coordinates theory.•Evaluates China's provincial environmental efficiency using Ray slack-based model.•Environmental efficiency is the highest in ...the east and lowest in central regions.•Detects environmental efficiency–economic growth relationship with spatial effect.•Identifies ways to develop environmental efficiency and regional economies.
The Chinese economy has been experiencing rapid growth since the implementation of the reform and opening-up policy. However, at the same time, it faces issues regarding resource savings and environmental protection, which are important aspects of the new industrialization. Therefore, this study conducts data envelopment analysis (DEA) to evaluate the environmental efficiency of Chinese regions. Certain existing DEA models account for undesirable outputs and do not elucidate the weak disposable relationship between undesirable and desirable outputs. Thus, polar theory is introduced among the DEA modeling in this study. First, drawing on stochastic frontier analysis, Ray stochastic frontier analysis, and DEA, we propose a Ray slack-based model (RSBM) to evaluate provincial environmental efficiencies in China from 2004 to 2012. Subsequently, an RSBM-Malmquist–Luenberger (total factor productivity) index is structured. Finally, economic growth, environmental efficiency, and energy consumption are analyzed using spatial panel econometrics. As this study treats industrial waste as undesirable outputs, the RSBM results show that the environmental efficiencies in the east are the highest, while those in the central regions are the lowest. The spatial econometric analysis reveals that the ratios of direct to total elasticity and those of direct to total effect for capital, labor, and energy input variables are fixed. Furthermore, the study provides policy implications and suggestions for future research.
Microgrids incorporated with distributed generation (DG) units and energy storage (ES) devices are expected to play more and more important roles in the future power systems. Yet, achieving efficient ...distributed economic dispatch in microgrids is a challenging issue due to the randomness and nonlinear characteristics of DG units and loads. This paper proposes a cooperative reinforcement learning algorithm for distributed economic dispatch in microgrids. Utilizing the learning algorithm can avoid the difficulty of stochastic modeling and high computational complexity. In the cooperative reinforcement learning algorithm, the function approximation is leveraged to deal with the large and continuous state spaces. And a diffusion strategy is incorporated to coordinate the actions of DG units and ES devices. Based on the proposed algorithm, each node in microgrids only needs to communicate with its local neighbors, without relying on any centralized controllers. Algorithm convergence is analyzed, and simulations based on real-world meteorological and load data are conducted to validate the performance of the proposed algorithm.
The explosive growth of content requests from mobile users is stretching the capability of current mobile networking technologies to satisfy users' demands with acceptable quality of service. An ...effective approach to address this challenge, which has not yet been thoroughly studied, is to offload network traffic by caching popular content at the edges (e.g., mobile devices and base stations) of mobile networks, thus reducing the massive duplication of content downloads. In this paper, we address the system modeling, large-scale optimization, and framework design of hierarchical edge caching in device-to-device aided mobile networks. In particular, taking into account the analysis of social behavior and preference of mobile users, heterogeneous cache sizes, and the derived system topology, we investigate the maximum capacity of the network infrastructure in terms of offloading network traffic, reducing system costs, and supporting content requests from mobile users locally. Our proposed framework has a low complexity and can be applied in practical engineering implementation. Trace-based simulation results demonstrate the effectiveness of the proposed framework.
Activation of apoptosis signal‐regulating kinase 1 (ASK1) is a key driving force of the progression of nonalcoholic steatohepatitis (NASH) and represents an attractive therapeutic target for NASH ...treatment. However, the molecular and cellular mechanisms underlying ASK1 activation in the pathogenesis of NASH remain incompletely understood. In this study, our data unequivocally indicated that hyperactivated ASK1 in hepatocytes is a potent inducer of hepatic stellate cell (HSC) activation by promoting the production of hepatocyte‐derived factors. Our previous serial studies have shown that the ubiquitination system plays a key role in regulating ASK1 activity during NASH progression. Here, we further demonstrated that tumor necrosis factor receptor–associated factor 6 (TRAF6) promotes lysine 6 (Lys6)‐linked polyubiquitination and subsequent activation of ASK1 to trigger the release of robust proinflammatory and profibrotic factors in hepatocytes, which, in turn, drive HSC activation and hepatic fibrosis. Consistent with the in vitro findings, diet‐induced liver inflammation and fibrosis were substantially attenuated in Traf6+/– mice, whereas hepatic TRAF6 overexpression exacerbated these abnormalities. Mechanistically, Lys6‐linked ubiquitination of ASK1 by TRAF6 facilitates the dissociation of thioredoxin from ASK1 and N‐terminal dimerization of ASK1, resulting in the boosted activation of ASK1‐c‐Jun N‐terminal kinase 1/2 (JNK1/2)‐mitogen‐activated protein kinase 14(p38) signaling cascade in hepatocytes. Conclusion: These results suggest that Lys6‐linked polyubiquitination of ASK1 by TRAF6 represents a mechanism underlying ASK1 activation in hepatocytes and a key driving force of proinflammatory and profibrogenic responses in NASH. Thus, inhibiting Lys6‐linked polyubiquitination of ASK1 may serve as a potential therapeutic target for NASH treatment.
The faithful storage and coherent manipulation of quantum states with matter-systems would enable the realization of large-scale quantum networks based on quantum repeaters. To achieve useful ...communication rates, highly multimode quantum memories are required to construct a multiplexed quantum repeater. Here, we present a demonstration of on-demand storage of orbital-angular-momentum states with weak coherent pulses at the single-photon-level in a rare-earth-ion-doped crystal. Through the combination of this spatial degree-of-freedom (DOF) with temporal and spectral degrees of freedom, we create a multiple-DOF memory with high multimode capacity. This device can serve as a quantum mode converter with high fidelity, which is a fundamental requirement for the construction of a multiplexed quantum repeater. This device further enables essentially arbitrary spectral and temporal manipulations of spatial-qutrit-encoded photonic pulses in real time. Therefore, the developed quantum memory can serve as a building block for scalable photonic quantum information processing architectures.
Owing to the presence of a substantial concentration of chlorine in seawater, the anode still faces severe chlorine corrosion, especially the water splitting operated at high current densities. ...Herein, the cost‐effective and scalable NiFe layered double hydroxides with carbonate intercalation (named as NiFe LDH_CO32−) are synthesized utilizing the etching‐hydrolysis and ion exchange strategies under ambient conditions. Experimental findings demonstrate that NiFe LDH_CO32− shows excellent stability at 500 and 1000 mA cm−2 for 1000 h under alkaline simulated seawater. Additionally, a two‐electrode system offers great stability at current densities ranging from 100 to 1000 mA cm−2 over a duration of 400 h in alkaline seawater. This remarkably catalytic stability can be ascribed to the etching‐hydrolysis and carbonate intercalation strategies. The etching‐hydrolysis strategy leads to an integrated electrode for the catalyst‐carrier, enhancing the adhesion between them, and retarding hence the divorce of catalysts from the carrier. Theoretical calculations suggest that the carbonate intercalation weakens the adsorbability of chlorine on catalysts and hinders the coupling of metal atoms with chlorine, thereby impeding the anode corrosion caused by chlorine and improving catalytic stability. More importantly, this strategy has been extended to the preparation of other layered double hydroxides with carbonate intercalation.
In this work, carbonate intercalation and etching‐hydrolysis strategies at room temperature and atmospheric pressure are deployed to synthesize the large‐scale and ultra‐stable electrodes for seawater splitting. The as obtained material (NiFe LDH_CO32−) exhibits impressive OER activity under alkaline simulated seawater, showing stable operation for 1000 h at 500 and 1000 mA cm−2.
Potassium‐ion batteries (PIBs) are recognized as promising alternatives for lithium‐ion batteries as the next‐generation energy storage systems. However, the larger radius of K+ hinders the K+ ...insertion into the conventional carbon electrode and results in sluggish potassiation kinetics and poor cycling stability. Here, nitrogen and fluorine dual doping of soft carbon nanotubes (NFSC) anode are synthesized in one pot, achieving extraordinary electrochemical performance for PIBs. It is demonstrated that NFSC with a doping dose of 5.6 at% nitrogen and 1.3 at% fluorine together exhibits the highest reversible capacity of 238 mAh g−1 at 0.2 A g−1 and cycling stability of 186 mAh g−1 after 1000 cycles at 1 A g−1. The extraordinary electrochemical performance can be attributed to the hollow structure, expanded interlayer distance, nitrogen and fluorine dual doping, and the binding ability of abundant defect sites. Moreover, density functional theory shows that the extra fluorine modification can dramatically enhance the conventional nitrogen doping effect and reduces the formation energy which makes a great contribution to the improvement of electrical conduction and K‐ions insert. This work may promote the development of low‐cost and sustainable carbon‐based materials for PIBs and other advanced energy storage devices.
The nitrogen and fluorine dual‐doped soft carbon fiber serves as the advanced anode for potassium ion battery. The dual‐doping effect is realized by locking the fluorine and nitrogen sources in the polypyrrole fiber cage which boosts the high conductivity, outstanding rate performance, and cycling stability.
The heterogeneous nature of tumour microenvironment (TME) underlying diverse treatment responses remains unclear in nasopharyngeal carcinoma (NPC). Here, we profile 176,447 cells from 10 NPC ...tumour-blood pairs, using single-cell transcriptome coupled with T cell receptor sequencing. Our analyses reveal 53 cell subtypes, including tumour-infiltrating CD8
T, regulatory T (Treg), and dendritic cells (DCs), as well as malignant cells with different Epstein-Barr virus infection status. Trajectory analyses reveal exhausted CD8
T and immune-suppressive TNFRSF4
Treg cells in tumours might derive from peripheral CX3CR1
CD8
T and naïve Treg cells, respectively. Moreover, we identify immune-regulatory and tolerogenic LAMP3
DCs. Noteworthily, we observe intensive inter-cell interactions among LAMP3
DCs, Treg, exhausted CD8
T, and malignant cells, suggesting potential cross-talks to foster an immune-suppressive niche for the TME. Collectively, our study uncovers the heterogeneity and interacting molecules of the TME in NPC at single-cell resolution, which provide insights into the mechanisms underlying NPC progression and the development of precise therapies for NPC.
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