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A bstract We develop covariant chiral kinetic theory with Landau level basis. We use it to investigate a magnetized plasma with a transverse electric field and a steady vorticity as perturbations. After taking into account vacuum shift in the latter case, we find the resulting current and stress tensor in both cases can be matched consistently with constitutive equations of magnetohydrodynamics. We find the solution in the vorticity case contains both shifts in temperature and chemical potential as well as excitations of the lowest Landau level states. The solution gives rise to an vector charge density and axial current density. The vacuum parts coming from both shifts and excitations agree with previous studies and the medium parts coming entirely from excitations leads to a new contribution to vector charge and axial current density consistent with standard chiral vortical effect.

With the development of deep fusion intelligent control technology and the application of low-carbon energy, the number of renewable energy sources connected to the distribution grid has been increasing year by year, gradually replacing traditional distribution grids with active distribution grids. In addition, as an important component of the distribution grid, substations have a complex internal environment and numerous devices. The problems of untimely defect detection and slow response during intelligent inspections are particularly prominent, posing risks and challenges to the safe and stable operation of active distribution grids. To address these issues, this paper proposes a high-performance and lightweight substation defect detection model called YOLO-Substation-large (YOLO-SS-large) based on YOLOv5m. The model improves lightweight performance based upon the FasterNet network structure and obtains the F-YOLOv5m model. Furthermore, in order to enhance the detection performance of the model for small object defects in substations, the normalized Wasserstein distance (NWD) and complete intersection over union (CIoU) loss functions are weighted and fused to design a novel loss function called NWD-CIoU. Lastly, based on the improved model mentioned above, the dynamic head module is introduced to unify the scale-aware, spatial-aware, and task-aware attention of the object detection heads of the model. Compared to the YOLOv5m model, the YOLO-SS-Large model achieves an average precision improvement of 0.3%, FPS enhancement of 43.5%, and parameter reduction of 41.0%. This improved model demonstrates significantly enhanced comprehensive performance, better meeting the requirements of the speed and precision for substation defect detection, and plays an important role in promoting the informatization and intelligent construction of active distribution grids.

Power network is one of the critical infrastructures, aiming to supply a reliable power. In general, some accidental and/or deliberate attacks may lead to large losses of power supply with severe social consequences. This paper considers a coarse‐grained model of power networks using a swing equation depending on the synchronous machine. Furthermore, we investigate the dynamical cascades failure, which is induced by power flows exceeding the capacity threshold of the transmission line. Therefore, a simple and flexible condition for synchronization is derived, which provides a new perspective for preventing cascading failure in oscillatory power network. The developed control approach is applied to several power network models to demonstrate its capability for suppressing cascading failures. In addition, it is found that the control effect strongly depends on the choice of control law. The study might be useful for enhancing the robustness of the power network or providing a more robust power supply.

Recent research and instances have demonstrated that most real-world systems can be effectively schematized by multiplex networks. Moreover, the interactions within systems often emerge among triadic or tetradic interactions, or even interactions with more element combinations, in addition to pairwise interactions. Hypergraph coupling structures are particularly well-suited for capturing such arbitrary higher-order interactions among nodes, thereby playing a key role in accurately depicting system dynamics. Meanwhile, the functionality of numerous complex systems depends on synchronization mechanisms. Therefore, this paper focuses on investigating the synchronous stability of a multiplex hypergraph. Specifically, we examine a three-layer network where intralayer interactions are represented by hyperedges, while the interlayer interactions are modeled through pairwise couplings. By generalizing the master stability function approach to the hypergraph structure, the synchronization phenomenon of such multiplex hypergraphs is analyzed. To verify our theoretical conclusions, we apply the proposed framework to networks of FitzHugh–Nagumo neurons and Rikitake two-disk dynamos. Simulation results unveil that the presence of higher-order interactions enhances the synchronous ability within the multiplex framework.

China’s life insurance industry has just started in the 1990s after the reform and opening up, and its development experience is obviously insufficient, and it has not gone through a very complete life insurance development cycle. No matter from the actuarial technology, the professional level of the agent, the popularization time of the agent system, or the management experience, it is far from the developed areas of the world’s life insurance industry. In addition, many professional investors are worried about the future prospects of China’s life insurance industry because of the long-term existence of a low interest rate environment. However, after reading detailed materials (research papers, books, reviews, etc.), the final conclusion of this report is different from that of other too cautious investors . This report holds that: the current situation and prospect of China’s life insurance H shares meet the conditions of Davis double-click, and the main investors in the secondary market will encounter a unique opportunity to obtain excess returns by investing in domestic insurance H shares. On the level of objective factors, we analyze from the following four aspects: (I) the potential demand for life insurance in China will continue to increase significantly in the future; (II) most of the representative life insurance companies in China have low valuations; (III) the possible style switching in China’s secondary market is conducive to the rise of blue chips such as life insurance companies; (IV) from the long-term perspective of history, the insurance index has significantly outperformed the Shanghai Composite Index, which represents the market. In terms of subjective factors, we consider them from the following four perspectives: (I) the development and problems of life insurance industry in Japan and Taiwan; (II) on the liability side, China’s life insurance industry vigorously develops new products with high business value, so as to resist the impact of low interest rates; (III) the diversification of asset allocation at the investment end of China’s life insurance industry can make the profit of life insurance industry not limited by the interest rate; (IV) the change of service quality at the supply side is conducive to the life insurance companies to tap the potential market demand in China.

Schisandra chinensis (Turcz.) Baill. (S. chinensis) and Schisandra sphenanthera Rehd. et Wils (S. sphenanthera) are called “Wuweizi” in traditional Chinese medicine, and they have distinct clinical applications. To systematically compare the differential characteristics of S. chinensis and S. sphenanthera, this study employed ultra-performance liquid chromatography–quadrupole time-of-flight mass spectrometry (UPLC-QTOF-MS) and gas chromatography–mass spectrometry (GC-MS) to construct chemical profiles of these two species from different regions. In total, 31 non-volatiles and 37 volatiles were identified in S. chinensis, whereas 40 non-volatiles and 34 volatiles were detected in S. sphenanthera. A multivariate statistical analysis showed that the non-volatiles tigloygomisin P, schisandrol A, schisantherin C, and 6-O-benzoylgomisin O and the volatiles ylangene, γ-muurolene, and β-pinene distinguish these species. Additionally, the metabolism of oxygen free radicals can contribute to the development of various diseases, including cardiovascular and neurodegenerative diseases. Therefore, antioxidant activities were evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) scavenging assays. The results showed that S. sphenanthera exhibited significantly higher antioxidant potential. A gray relational analysis indicated that the key contributors to the antioxidant activity of S. chinensis were schisandrol A, gomisin G, schisantherin C, pregomisin, gomisin J, and schisantherin B. For S. sphenanthera, the key contributors included gomisin K2, schisantherin B, gomisin J, pregomisin, schisantherin C, schisandrin, gomisin G, schisantherin A, schisanhenol, and α-pinene. The identification of the differential chemical markers and the evaluation of the antioxidant activities provide a foundation for further research into the therapeutic applications of these species. This innovative study provides a robust framework for the quality control and therapeutic application of S. chinensis and S. sphenanthera, offering new insights into their medicinal potential.

Epidemiological studies have associated high levels of airborne particulate matter (PM) with increased respiratory diseases. In order to investigate the mechanisms of air pollution-induced lung toxicity in humans, human bronchial epithelial cells (16HBE) were exposed to various concentrations of particles smaller than 2.5 μm (PM2.5) collected from Beijing, China. After observing that PM2.5 decreased cell viability in a dose-dependent manner, we first used Illumina RNA-seq to identify genes and pathways that may contribute to PM2.5-induced toxicity to 16HBE cells. A total of 539 genes, 283 up-regulated and 256 down-regulated, were identified to be significantly differentially expressed after exposure to 25 μg/cm2 PM2.5. PM2.5 induced a large number of genes involved in responses to xenobtiotic stimuli, metabolic response, and inflammatory and immune response pathways such as MAPK signaling and cytokine-cytokine receptor interaction, which might contribute to PM2.5-related pulmonary diseases. We then confirmed our RNA-seq results by qPCR and by analysis of IL-6, CYP1A1, and IL-8 protein expression. Finally, ELISA assay demonstrated a significant association between exposure to PM2.5 and secretion of IL-6. This research provides a new insight into the mechanisms underlying PM2.5-induced respiratory diseases in Beijing.

The orchid Dendrobium officinale grows throughout southeast China and southeast Asian countries and is used to treat inflammation and diabetes in traditional Chinese medicine. Tie pi feng dou is a well-known traditional Chinese medicine made from the dried D. officinale stems. Processing alters the physicochemical properties of TPFD; however, it is unclear how processing affects the quality and medicinal value of this plant. Here, we analyzed and compared the chemical composition of fresh stems of D. officinale and TPFD and explored possible explanations for the enhanced medicinal efficacy of processed D. officinale stems using qualitative and quantitative methods. To identify the components of FSD and TPFD, we used ultra-high-performance liquid chromatography combined with mass spectrometry in negative and positive ion modes and interpreted the data using the Human Metabolome Database and multivariate statistical analysis. We detected 23,709 peaks and identified 2352 metabolites; 370 of these metabolites were differentially abundant between FSD and TPFD (245 more abundant in TPFD than in FSD, and 125 less abundant), including organooxygen compounds, prenol lipids, flavonoids, carboxylic acids and their derivatives, and fatty acyls. Of these, 43 chemical markers clearly distinguished between FSD and TPFD samples, as confirmed using orthogonal partial least squares discriminant analysis. A pharmacological activity analysis showed that, compared with FSD, TPFD had significantly higher levels of some metabolites with anti-inflammatory activity, consistent with its use to treat inflammation. In addition to revealing the basis of the medicinal efficacy of TPFD, this study supports the benefits of the traditional usage of D. officinale .

Vulnerability is a major concern for power networks. Malicious attacks have the potential to trigger cascading failures and large blackouts. The robustness of power networks against line failure has been of interest in the past several years. However, this scenario cannot cover weighted situations in the real world. This paper investigates the vulnerability of weighted power networks. Firstly, we propose a more practical capacity model to investigate the cascading failure of weighted power networks under different attack strategies. Results show that the smaller threshold of the capacity parameter can enhance the vulnerability of weighted power networks. Furthermore, a weighted electrical cyber-physical interdependent network is developed to study the vulnerability and failure dynamics of the entire power network. We perform simulations in the IEEE 118 Bus case to evaluate the vulnerability under various coupling schemes and different attack strategies. Simulation results show that heavier loads increase the likelihood of blackouts and that different coupling strategies play a crucial role in the cascading failure performance.

Community structure exists widely in real social networks. To investigate the effect of community structure on the spreading of infectious diseases, this paper proposes a community network model that considers both the connection rate and the number of connected edges. Based on the presented community network, a new SIRS transmission model is constructed via the mean-field theory. Furthermore, the basic reproduction number of the model is calculated via the next-generation matrix method. The results reveal that the connection rate and the number of connected edges of the community nodes play crucial roles in the spreading process of infectious diseases. Specifically, it is demonstrated that the basic reproduction number of the model decreases as the community strength increases. However, the density of infected individuals within the community increases as the community strength increases. For community networks with weak strength, infectious diseases are likely not to be eradicated and eventually will become endemic. Therefore, controlling the frequency and range of intercommunity contact will be an effective initiative to curb outbreaks of infectious diseases throughout the network. Our results can provide a theoretical basis for preventing and controlling the spreading of infectious diseases.