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Proactive ambulance management is constructive to improve the response efficiency for emergency medical service (EMS) systems under uncertainty. In this paper, we present a dynamic optimisation model concerning the ambulance dispatching and relocation. We develop a flexible operation policy driven by the interval rolling to match vehicles with calls in batch. We formulate the problem in Markov Decision Process and incorporate M / G / c queues to minimise the average response and delay time. Considering the curse-of-dimensionality, we provide a simulation-based empirical dynamic programming with the state aggregation and post-decision state to solve the model. To further accelerate the computational efficiency, a greedy heuristic method is introduced to improve the quality of sampling operations. Then, a risk-averse model is developed based on the stochastic dominance strategy to improve operational reliability. We develop an equivalent linear programming to evaluate concave dominating functions. We test the performance by a numerical case and extract managerial insights for practitioners. Our results show that the proposed flexible and risk-averse solution outperforms the classic model on reducing the delay under uncertain calls. And the improvement is more active during peak hours, when real-time needs exceed available ambulances. [ABSTRACT FROM AUTHOR]

Information asymmetry leads to short-term competitive antagonism between downstream manufacturers and upstream suppliers. This paper applies a master-slave game to reproduce the interest conflict between a manufacturer and a supplier, and proposes a cooperative decision-making model based on information sharing, considering the interest consistency of upstream supply chain members. Additionally, the overall profit coordination mechanism is constructed to ensure the continuation of the cooperative decision-making relationship. In addition, to ensure that the supplier participating in cooperative decision-making has the supply capacity desired by the manufacturer, a rational evaluation system combined with game theory is employed to determine the most suitable participating supplier. A numerical example is given to demonstrate the systematization and effectiveness of the proposed method. Finally, through sensitivity analysis and comparative analysis, managerial insights and recommendations are obtained. [ABSTRACT FROM AUTHOR]

Atractylenolide‐III (AT‐III) is well known as its role in antioxidant and anti‐inflammatory. Present study was aimed to figure out its effects on osteoarthritis and potential mechanisms. Rat model, human osteoarthritis cartilage explants as well as rat/human chondrocyte cultures were prepared to test AT‐III's effects on osteoarthritis progression and chondrocyte senescence. Potential targeted molecules of AT‐III were predicted using network pharmacology and molecular docking, assessed by Western blotting and then verified with rescue experiments. AT‐III treatment alleviated osteoarthritis severity (shown by OARSI grading score and micro‐CT) and chondrocyte senescence (indexed by levels of SA‐β‐gal, P16, P53, MMP13, ROS and ratio of healthy/collapsed mitochondrial membrane potentials). Network pharmacology and molecular docking suggested that AT‐III might play role through NF‐κB pathway. Further experiments revealed that AT‐III reduced phosphorylation of IKKα/β, IκBα and P65 in NF‐κB pathway. As well as nuclear translocation of p65. Both in vivo and in vitro experiments indicated that AT‐III's effects on osteoarthritis and anti‐senescence were reversed by an NF‐κB agonist. AT‐III could alleviate osteoarthritis by inhibiting chondrocyte senescence through NF‐κB pathway, which indicated that AT‐III is a prospective drug for osteoarthritis treatment. [ABSTRACT FROM AUTHOR]

Blockchain technology is applied for product traceability in e‐commerce supply chains. In this context, the paper investigates the channel problem and decision timing problem considering product traceability. Using game‐theoretic framework, the manufacturer encroachment strategies, order quantities and profits under different channel structure, and traceability level are characterized. Research shows that selling traceability products can expand potential market demand and increase the sales volume of products and the profits of manufacturers and retailers. Under encroachment, members with information advantage can maximize their own profits. Additionally, manufacturers can regain the high ground by adjusting traceability levels to influence wholesale prices. [ABSTRACT FROM AUTHOR]

Crystal-field perturbation is theoretically the most direct and effective method of achieving highly efficient photoluminescence from trivalent lanthanide (Ln3+) ions through breaking the parity-forbidden nature of their 4f-transitions. However, exerting such crystal-field perturbation remains an arduous task even in well-developed Ln3+-doped luminescent nanocrystals (NCs). Herein, we report crystal-field perturbation through interstitial H+-doping in orthorhombic-phase NaMgF3:Ln3+ NCs and achieve a three-orders-of-magnitude emission amplification without a distinct lattice distortion. Mechanistic studies reveal that the interstitial H+ ions perturb the local charge density distribution, leading to anisotropic polarization of the F− ligand, which affects the highly symmetric Ln3+-substituted [MgF6]4− octahedral clusters. This effectively alleviates the parity-forbidden selective rule to enhance the 4f–4 f radiative transition rate of the Ln3+ emitter and is directly corroborated by the apparent shortening of the radiative recombination lifetime. The interstitially H+-doped NaMgF3:Yb/Er NCs are successfully used as bioimaging agents for real-time vascular imaging. These findings provide concrete evidence for crystal-field perturbation effects and promote the design of Ln3+-doped luminescent NCs with high brightness. Lanthanide-doped inorganic nanocrystals are promising for optical imaging and biomedical applications. Here authors show that interstitial H+ doping-induced crystal-field perturbation enhances the photoluminescence intensity of lanthanide-doped inorganic nanocrystals. [ABSTRACT FROM AUTHOR]

In radar array signal processing, weak nonstationary polarization signal direction of arrival (DOA) estimation is a challenging and significant issue when both strong and weak nonstationary signals coexist. Time-frequency (T-F) analysis is an effective method to deal with nonstationary signals. In the last decade, spatial time-frequency distributions (STFDs) have been proposed for multiple dual-polarization antenna arrays and efficaciously used for nonstationary signal DOA estimation. In this article, we introduced a novelty means for estimating weak nonstationary polarization signal DOA by utilizing spatial polarimetric time-frequency distributions (SPTFDs) of cross terms when there are strong nonstationary polarization interference signals and additive Gaussian white noise. The cross terms' SPTFDs are considered via a replaceability matrix for data covariance in multiple signal classification (MUSIC) and the estimation of signal parameters using the rotational invariance technique (ESPRIT). Combining the STFDs of cross terms with polarization information about weak nonstationary signals improves signal DOA estimation accuracy. The combined MUSIC and ESPRIT are used in the algorithm to further ensure the success probability and accuracy of DOA estimation. Through simulation analyses, the proposed algorithm is more suitable for the required application scenarios than other algorithms and is superior to other algorithms. [ABSTRACT FROM AUTHOR]