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High-performance concrete (HPC) experiences significant degradation in its mechanical properties after fire exposure. While various post-fire curing methods have been proposed to rehabilitate thermally damaged concrete (TDC), the physical and chemical changes occurring during these processes are not well-understood. This study examines the strength and microstructure restoration of HPC through water and water–CO2 cyclic recuring. HPC samples were initially heated to 600 °C and 900 °C, then subjected to water and cyclic recuring. Results indicate that the mechanical performance recovery of thermally damaged HPC is significantly better with cyclic recuring than with water recuring. The compressive strength of HPC samples exposed to 600 °C and 900 °C reached 131.6% and 70.3% of their original strength, respectively, after cyclic recuring. The optimal recuring duration for substantial recovery in thermally damaged HPC was determined to be 18 days. The strength recovery is primarily due to the healing of microcracks and the densification of decomposed cement paste. These findings clarify the physical and chemical processes involved in post-fire curing of HPC, highlighting the potential of water and water–CO2 cyclic recuring in the rehabilitation of TDC. [ABSTRACT FROM AUTHOR]

The timely injection of gangue slurry into the mining space formed after coal mining can scale up the disposal of gangue and control surface deformation. However, the waterproof effect of gangue slurry in the mining space remains unclear, necessitating urgent investigation into the permeability characteristics of compacted backfill bodies of gangue slurry under the action of overburden. In this study, a multi-field coupled seepage test system for backfill materials was developed based on Forchheimer's nonlinear seepage law, and a laboratory preparation method for compacted backfill body (CBB) of gangue slurry after grouting and backfilling in mining space under pseudo-triaxial conditions was proposed. Additionally, the pressure bleeding characteristics of gangue slurry under the action of overburden were studied, the variation law of permeability of the CBB with the axial pressure, a particle size range, and cement dosage was revealed, and the determination method for the permeability level of the CBB and its optimization method were put forward. The research results indicate that there are obvious staged characteristics in the pressure bleeding changes in gangue slurry. Axial pressure, particle size range, and cement dosage all have a significant impact on the permeability of the CBB. The permeability level of the CBB of gangue slurry is within the range of poor permeability and extremely poor permeability. After backfilling into the mining space, gangue slurry exhibits a significant water-blocking effect. [ABSTRACT FROM AUTHOR]

Multi-group data, which include the same set of variables on separate groups of samples, are commonly seen in practice. Such data structure consists of data from multiple groups and can be challenging to analyze due to data heterogeneity. We propose a novel Joint and Individual Component Regression (JICO) model to analyze multi-group data. Our proposed model decomposes the response into shared and group-specific components, which are driven by low-rank approximations of joint and individual structures from the predictors respectively. The joint structure has the same regression coefficients across multiple groups, whereas individual structures have group-specific regression coefficients. We formulate this framework under the representation of latent components and propose an iterative algorithm to solve for the joint and individual scores. We us the Continuum Regression (CR) to estimate the latent scores, which provides a unified framework that covers the Ordinary Least Squares (OLS), the Partial Least Squares (PLS), and the Principal Component Regression (PCR) as its special cases. We show that JICO attains a good balance between global and group-specific models and remains flexible due to the usage of CR. We conduct simulation studies and analysis of an Alzheimer's disease dataset to further demonstrate the effectiveness of JICO. R package of JICO is available online at . for this article are available online. [ABSTRACT FROM AUTHOR]

Extracting geoscientific dataset names from the literature is crucial for building a literature–data association network, which can help readers access the data quickly through the Internet. However, the existing named-entity extraction methods have low accuracy in extracting geoscientific dataset names from unstructured text because geoscientific dataset names are a complex combination of multiple elements, such as geospatial coverage, temporal coverage, scale or resolution, theme content, and version. This paper proposes a new method based on the hierarchical temporal memory (HTM) model, a brain-inspired neural network with superior performance in high-level cognitive tasks, to accurately extract geoscientific dataset names from unstructured text. First, a word-encoding method based on the Unicode values of characters for the HTM model was proposed. Then, over 12,000 dataset names were collected from geoscience data-sharing websites and encoded into binary vectors to train the HTM model. We conceived a new classifier scheme for the HTM model that decodes the predictive vector for the encoder of the next word so that the similarity of the encoders of the predictive next word and the real next word can be computed. If the similarity is greater than a specified threshold, the real next word can be regarded as part of the name, and a successive word set forms the full geoscientific dataset name. We used the trained HTM model to extract geoscientific dataset names from 100 papers. Our method achieved an F1-score of 0.727, outperforming the GPT-4- and Claude-3-based few-shot learning (FSL) method, with F1-scores of 0.698 and 0.72, respectively. [ABSTRACT FROM AUTHOR]

The rapid development of AI-related technologies and the upsurge of Metaverse are driving AI musicians into people's lives. To clarify the link between anthropomorphism, users' perceptions, and attitudes, and to explore the impact of listening type (listening to AI-generated music or not) on the relationship between anthropomorphism and users' perceptions, we conducted a 2 × 2 experiment based on the two basic dimensions of social cognition. A total of 211 valid samples were collected and the partial least squares (PLS) method was used for data analysis to test the research model and hypotheses. The results show that more human-like AI musicians elicit higher users' competence perceptions, which are crucial facilitators of users' attitudes towards AI musicians; higher warmth perceptions help users form better attitudes towards AI musicians; listening to AI-generated music or not moderates the impact of anthropomorphism degree on users' competence perceptions. This study promotes the understanding of the impact of AI musicians' anthropomorphism and guides the design of AI musicians' images to some extent. [ABSTRACT FROM AUTHOR]

A two-unit symmetrical composite structure with the WSMs defect layer was designed. The energy band and transmission properties are studied based on the transfer matrix theory. Due to the WSMs with the property of time-reversal breaking, the nonreciprocal Tamm states for forward and backward incidence are excited in the interface of the symmetrical composite structure. The numerical results show that the nonreciprocity of the Tamm states is enhanced with an increase in the WSMs thickness. By choosing the appropriate geometric parameters of dielectric layers, two pairs of nonreciprocal dispersive curves are obtained in the two-band gap. The present scenario can be applied in some areas, such as optical isolators and multi-channel nonreciprocal transmission devices. [ABSTRACT FROM AUTHOR]

All-solid-state fluoride-ion batteries (FIBs) with a high theoretical energy density have attracted considerable attention due to their enhanced safety features and superior capacity. The selection of solid electrolyte materials with enhanced fluoride-ion conductivity is crucial for the successful implementation of high fluoride-ion energy storage in realistic scenarios. In this study, heterogeneous solid fluoride-ion electrolytes with different ratios of (LaF3)1−x(PbF2)x are investigated. In contrast to other research efforts focusing on the development of single-phase, single-lattice-defect solid-state electrolytes, the (LaF3)1−x(PbF2)x material incorporates two phases with different defects, namely fluoride vacancies and mobile fluoride ions. This unique combination of defects results in a significant enhancement in conductivity while maintaining their coexistence. The crystal gaps are filled by the orthorhombic phase, which is conductive, resulting in a reduction of the contact resistance due to the uniform distribution of the three crystal phases and the heterointerface between the hexagonal phase and the cubic phase. The multi-component electrolyte (LaF3)0.4(PbF2)0.6 exhibits the best performance among the samples tested. The electrolyte exhibits a high fluoride-ion conductivity, with a value of 2.78 × 10−4 S cm−1 at 120 °C and 6.37 × 10−6 S cm−1 at room temperature. The electronic conductivity is negligible with a value of 5.48 × 10−8 S cm−1. Furthermore, the electrolyte has an electrochemical stability window of 1.85 V vs. Sn/Sn2+. Due to its favorable electrochemical properties, this material has considerable potential as a solid-state fluoride-ion electrolyte. [ABSTRACT FROM AUTHOR]

As a novel technology for slope protection, living stumps have demonstrated the ability to significantly enhance slope stability. This study aims to investigate the mechanical properties of living-stump root systems and their reinforcement mechanisms on slopes through three-dimensional modeling tests. Using ABS materials, a 3D model of a living elm stump was created via 3D printing; this was followed by slope model testing. The reinforcement mechanisms of living stumps were examined through a combination of model testing and numerical simulation. The results reveal that the presence of living stumps in the lower and middle sections of a slope causes the maximum-shear-stress zone of the soil to shift deeper. The stress distribution around the living stump is notably improved owing to the lateral root system. Living stumps positioned in the lower part of the slope intersect the potential sliding surface, gradually transferring soil shear stress to the root system through root–soil interactions. Furthermore, the tap roots and lateral roots of living stumps form a robust spatial network that can collectively withstand soil shear stress, thereby enhancing slope stability. [ABSTRACT FROM AUTHOR]

To address transmission failures in traditional Ad Hoc networks, which was caused by highly dynamic topologies, short-lived connections characteristics, a reliable forwarding strategy based on link stability and content accessibility forwarding (RF-LSCA) based on the named data networking (NDN) architecture was designed. A multi-attribute decision-making method was utilized as the foundation for this strategy, with consideration given to link duration, distances between nodes, and content accessibility. This enabled a more precise selection of the optimal forwarding node, thereby enhancing the content transmission performance. Furthermore, given the potential instability of a single optimal path, the decision model was combined with probabilistic forwarding to design a low-overhead yet highly reliable redundant forwarding mechanism. The full exploitation of NDN's multipath characteristics was achieved through this design, thereby ensuring content delivery efficiency in mobile scenarios. Through simulation experiments, the proposed RFLSCA is demonstrated to outperform existing strategies in key performance metrics, including average content retrieval delay, average hop counts, and content satisfaction rate. These results provide ample evidence of its superiority in enhancing transmission efficiency within NDN-Ad Hoc networks. [ABSTRACT FROM AUTHOR]

The deployment of Li–S batteries in the commercial sector faces obstacles due to their low electrical conductivity, slow redox reactions, quick fading of capacity, and reduced coulombic efficiency. These issues stem from the "shuttle effect" associated with lithium polysulfides (LiPSs). In this work, a haystack-like CeO2 derived from a cerium-based metal-organic framework (Ce-MOF) is obtained for the modification of a polypropylene separator. The carbon framework and CeO2 coexist in this haystack-like structure and contribute to a synergistic effect on the restriction of LiPSs shuttling. The carbon network enhances electron transfer in the conversion of LiPSs, improving the rate performance of the battery. Moreover, CeO2 enhances the redox kinetics of LiPSs, effectively reducing the "shuttle effect" in Li–S batteries. The Li–S battery with the optimized CeO2 modified separator shows an initial discharge capacity of 870.7 mAh/g at 2 C, maintaining excellent capacity over 500 cycles. This research offers insights into designing functional separators to mitigate the "shuttle effect" in Li–S batteries. [ABSTRACT FROM AUTHOR]

Mass transfer from liquid to gas phase is a crucial process in chemical engineering. Due to the heterogeneity and dynamic nature of the phase transition process, monitoring the structural changes of compounds during this process is challenging. In this work, a combining of the mass spectrometry‐based method and quantum chemistry calculations was used to study the structural changes during liquid‐to‐gas phase transitions. Electrospray is used to induce the transition of phenolic acid molecules from the liquid phase to the gas phase. The deprotonated structures were captured and separated using ion mobility mass spectrometry. Deprotonated structures helped to identify the most acidic functional group within the molecule. These deprotonated structures were confirmed by collision‐induced dissociation and molecular collision cross‐section measurements. Quantum chemistry calculations revealed the mechanisms about the variation of intramolecular acid site and "kinetic trapping." Three liquid‐to‐gas phase transformation models were proposed, demonstrating that the variation in free energy among different deprotonated structures governs the thermodynamic/kinetic process of the liquid‐to‐gas phase conversion. [ABSTRACT FROM AUTHOR]

The transiting mechanism of abnormal brain functional activities, such as the epileptic seizures, has not been fully elucidated. In this study, we employ a probabilistic neural network model to investigate the impact of negative regulation, including negative connections and negative inputs, on the dynamical transition behavior of network dynamics. It is observed that negative connections significantly influence the transition behavior of the network, intensifying the oscillation of discharge probability, corresponding to uneven discharge and epileptic states. Negative inputs, within a certain range, exhibited a similar impact on the dynamic state of the network as negative connections, enhancing network oscillations and resulting in higher fragility. However, larger negative inputs can led to the disappearance of oscillations in the discharge probability, indicating a maintenance of lower fragility. We speculate that negative regulation may be an indispensable factor in the occurrence of epileptic seizures, and future research should give it due consideration. [ABSTRACT FROM AUTHOR]

Existing product service system (PSS)-related reviews rarely probe into the evolution of PSS-related research topics, leaving it difficult for researchers to grasp the development process of PSS research. The current study, by constructing an evolutionary graph of PSS research topics, aims to elucidate the development process of PSS research. Bibliometric analysis and topic modelling have been combined to construct the evolutionary graph of PSS research topics for 2753 records from 2000 to 2023. The clustering and time-zone graphs of co-occurring keywords have been constructed using the Citespace tool to determine four PSS research fields. The research topics have been mined from the abstracts in each year's corpus via the Latent Dirichlet Allocation (LDA) algorithm. The labels of each research topic have been determined by analysing the distribution of topic words in combination with emerging keywords. Each topic label has been assigned to the corresponding research field, resulting in an evolutionary graph of PSS research topics. Then, each evolutionary route has been summarised and analysed in detail. The outcomes reveal that digital and smart technologies have a profound impact on PSS. On this basis, several PSS research agendas are proposed for future studies. [ABSTRACT FROM AUTHOR]

We have successfully synthesized ultrathin nanowires of pure Pt, Pt99Ni1, Pt9Ni1, and Pt7Ni3 using a modified room‐temperature soft‐template method. Analysis of both methanol oxidation reaction (MOR) and ethanol oxidation reaction (EOR) results found that the Pt7Ni3 samples yielded the best performance with specific activities of 0.36 and 0.34 mA/cm2 respectively. Additionally, formic acid oxidation reaction (FAOR) tests noted that both Pt and PtNi nanowires oxidize small organic molecules (SOMs) via an indirect pathway. CO oxidation data suggests little measurable performance without any pre‐reduction treatment; however, after annealing in H2, we detected significantly improved CO2 formation for both Pt9Ni1 and Pt7Ni3 motifs. These observations highlight the importance of pre‐treating these nanowires under a reducing atmosphere to enhance their performance for CO oxidation. To explain these findings, we collected extended x‐ray adsorption fine structure (EXAFS) spectroscopy data, consistent with the presence of partial alloying with a tendency for Pt and Ni to segregate, thereby implying the formation of a Pt‐rich shell coupled with a Ni‐rich core. We also observed that the degree of alloying within the nanowires increased after annealing in a reducing atmosphere, a finding deduced through analysis of the coordination numbers and calculations of Cowley's short range order parameters. [ABSTRACT FROM AUTHOR]