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Addressing the formidable challenges in spatial infrared dim target detection, this paper introduces an advanced detection approach based on the refinement of the YOLOv8 algorithm. In contrast to the conventional YOLOv8, our method achieves remarkable improvements in detection accuracy through several novel strategies. Notably, by incorporating a deformable convolutional module into the YOLOv8 backbone network, our method effectively captures more intricate image features, laying a solid foundation for subsequent feature fusion and detection head predictions. Furthermore, a dedicated small target detection layer, built upon the original model, significantly enhances the model’s capability in recognizing infrared small targets, thereby boosting overall detection performance. Additionally, we utilize the WIoU-v3 as the localization regression loss function, effectively reducing sensitivity to positional errors and leveraging the advantages of multi-attention mechanisms. To enrich the quantity and quality of the spatial infrared dim target dataset, we employ image enhancement techniques to augment the original dataset. Extensive experiments demonstrate the exceptional performance of our method. Specifically, our approach achieves a precision of 95.6%, a recall rate of 94.7%, and a mean average precision (mAP) exceeding 97.4%, representing substantial improvements over the traditional YOLOv8 algorithm. Moreover, our detection speed reaches 59 frames/s, satisfying the requirements for real-time detection. This achievement not only validates the efficacy and superiority of our algorithm in spatial infrared dim target detection, but also offers novel insights and methodologies for research and applications in related fields, holding immense potential for future applications.

Abstract In cross-country skiing competitions, the choice of pacing strategy is of decisive significance to athletes' performance. A reasonable pacing strategy is essential for athletes to improve their performance. In this paper, the mathematical models of cross-country skiing simulation and pacing optimization are established, including motion model, athlete power output model, and optimization model. The actual competition data of a Chinese athlete in Guyangshu 1.5 km track was compared with the model simulation results. The whole process time error is less than 3%, which verifies the accuracy of the motion and power output model. Gauss pseudo-spectral method is applied to the optimization model. By changing the distribution of athletes' power output, the racing time is minimized under the condition that the total energy output remains unchanged. Compared with the pacing strategy before optimization, the optimized racing time was shortened by 12.6 s, which verifies the effectiveness of the optimization model. Optimized results show that in the first significant uphill section, a recommendation is to use a more conservative strategy, while in the latter half of uphill sections the power output should be increased.

ObjectiveTo determine the pathogen and phylogenetic characteristics of an uncommon outbreak of recombinant norovirus infection in Daishan County in February 2022.MethodsFluorescence quantitative PCR was used to detect the norovirus in the eight anal swabs collected in the outbreak. In the positive samples， reverse transcription PCR were used to amplify the norovirus. Norovirus sequences were characterized by MEGA7 and Simplot.ResultsNorovirus GⅠ was identified in all eight anal samples. It was further determined to be recombinant norovirus GⅠ.6 ［P11］， with the recombination site at the ORF1-ORF2 junction. The sequence had the highest nucleotide identity （98.75%） to a GⅠ.6［P11］ strain collected in 2018 （GenBank accession number MT357995）.ConclusionAccording to the etiological identification and phylogenetic analysis， this outbreak is confirmed to be caused by the uncommon recombinant norovirus GⅠ.6 ［P11］ in China.

This paper discusses consensus control of nonlinear coupled parabolic PDE-ODE-based multi-agent systems (PDE-ODEMASs). First, a consensus controller of leaderless PDE-ODEMASs is designed. Based on a Lyapunov-based approach, coupling strengths are obtained for leaderless PDE-ODEMASs to achieve leaderless consensus. Furthermore, a consensus controller in the leader-following PDE-ODEMAS is designed and the corresponding coupling strengths are obtained to ensure the leader-following consensus. Two examples show the effectiveness of the proposed methods.

Using the largest semi-autogenous grinding mill in China as a model, collision energy was analyzed on the basis of the multi-layer kinematics of the steel balls. First, the kinematic equation of the steel balls was obtained by considering the multi-layer characteristics of the steel balls. Second, the collision energy of the inner-layer steel balls was addressed according to its kinematic characteristics. Finally, the total collision energy per unit time was obtained. Results show that the leaving angle decreases as the mill speed ratio increases and as the radius ratio increases, but the leaving velocity increases linearly. Moreover, a discontinuity point of the tangential collision velocity occurs at an angle factor β = 0, and the angle factor β is divided into two intervals: [−3, 0] and [0, 1.5]. The leaving angles corresponding to a tangential velocity equal to zero are calculated to be 1.185 and 0.7854 rad in the two intervals. In addition, the sum collision velocity increases when β is less than zero, but it decreases sharply above zero. The maximum total collision energy per unit time occurs at 84.2% of the mill speed corresponding to the optimal mill speed ratio.

We present a design for a two-dimensional omnidirectional acoustic absorber that can achieve 98.6% absorption of acoustic waves in water, forming an effective acoustic black hole. This artificial black hole consists of an absorptive core coated with layers of periodically distributed polymer cylinders embedded in water. Effective medium theory describes the response of the coating layers to the acoustic waves. The polymer parameters can be adjusted, allowing practical fabrication of the absorber. Since the proposed structure does not rely on resonances, it is applicable to broad bandwidths. The design might be extended to a variety of applications.

Recent explorations of topology in physical systems have led to a new paradigm of condensed matters characterized by topologically protected states and phase transition, for example, topologically protected photonic crystals enabled by magneto-optical effects. However, in other wave systems such as acoustics, topological states cannot be simply reproduced due to the absence of similar magnetics-related sound–matter interactions in naturally available materials. Here, we propose an acoustic topological structure by creating an effective gauge magnetic field for sound using circularly flowing air in the designed acoustic ring resonators. The created gauge magnetic field breaks the time-reversal symmetry, and therefore topological properties can be designed to be nontrivial with non-zero Chern numbers and thus to enable a topological sonic crystal, in which the topologically protected acoustic edge-state transport is observed, featuring robust one-way propagation characteristics against a variety of topological defects and impurities. Our results open a new venue to non-magnetic topological structures and promise a unique approach to effective manipulation of acoustic interfacial transport at will.

We design a structure to realize Rabi splitting and Rabi oscillation in acoustics. We develop rigorous analytical models to analyze the splitting effect from the aspect of phase matching, and from the aspect of mode coupling using a coupled mode model. In this model, we discover that the splitting effect is caused by the coupling of the Fabry–Perot fundamental mode with the resonant mode of an artificial acoustic ‘atom’. We then extract the coupling strength and analyze the impact of structural parameters on it. In addition, we demonstrate Rabi oscillation in the time domain. Such quantum phenomena in the classical regime may have potential applications in the design of novel ultrasonic devices.

The three large irrigation schemes, namely Bojili, Xiaokaihe and Handun irrigation scheme, in Binzhou City of Shandong Province include in the pilot list of digital twin irrigation schemes by the Ministry of Water Resoucres. This paper systemically introduced the overall design structure of digital twin irrigation scheme for the three large irrigation schemes, as well as the construction components and technical approaches for the digital twin irrigation development in the three irrigation schemes, including, data base, vertical monitoring system, canal automation, models, support system and management platform, etc. The construction of the digital twin irrigation schemes in the three large irrigation schemes in Binzhou City is based on the existing information system. The total investment has reach more than 42.8 million RMB Yuan, and the major part of the pilot project has completed and put into use successfully and received good application results. The application of water schedule model could reduce planning time by 60% and saving water by 6%, and canal automation could save labor by 40%. With the further development, updating and application of the digital twin irrigation technology in the three large irrigation schemes, irrigation water management can be further improved by increasing digital, intelligent and precise management, which will contribute to high quality and sustainable development of irrigation schemes.

【Objective】 Optimizing water distribution in canal-irrigation districts is a prerequisite to improve irrigation water use efficiency. This paper proposes an optimization method to distribute water in two-level canal-irrigation systems. 【Method】 The method was based on water supply to irrigation districts; it optimizes volume of water distribution, water distribution flow rate and time for each water use unit. We considered two scenarios. The first one was insufficient irrigation where water supply cannot meet water demand during the growing season of crops, in which the model calculated the allocated water for each water user first using water resource allocation coefficient, and then determined the water distribution using the optimal distribution model. The second was sufficient irrigation where water supply meets water demand; we first ranked the priority of the water distribution to each user, and then determined the volume of optimal water flow and timing. The objective of the optimization in both scenarios was to maximize water flow rate and expedite water distribution. The model was applied to the Bojili Irrigation District. 【Result】 The model can optimally allocate and distribute water across the canal system. When water supply is ample, the model can optimally determine water distribution sequence based on the allocation coefficient. When water is scarce, the model can optimally allocate water to each user based on the distribution coefficient. In both scenarios, water distribution flow rate in the main and branched canals exceed 80% and 75% of the maximum flow limits in the first and second scenarios, respectively. The water distribution period for the first and second scenarios is 10.90 and 17.84 days, respectively. 【Conclusion】 The model we developed is effective and provides an improved water allocation method for water management in irrigation districts.

Abstract Background Intervertebral disc degeneration (IDD) is a progressive age‐related disorder characterized by the reduction in the number of nucleus pulposus cells (NPCs) and degradation of extracellular matrix (ECM), thereby leading to chronic pain and disability. The pathogenesis of IDD is multifaceted, and current therapeutic strategies remain limited. The nucleus pulposus (NP), primarily composed of NPCs, proteoglycans, and type II collagen, constitutes essential components for maintaining intervertebral disc (IVD) function and spinal motion. The disturbed homeostasis of NPCs is closely associated with IDD. Accumulating evidence increasingly suggests the crucial role of programmed cell death (PCD) in regulating the homeostasis of NPCs. Aims This review aimed to elucidate various forms of PCD and their respective roles in IDD, and investigate diverse strategies targeting the cell death of NPCs for IDD treatment. Materials & Methods We collected the relevant literature regarding PCD and their roles in the development of IDD. Subsequently, we comprehensively summarized the intricate association between PCD and IDD, and also explored the potential and application of cell therapy and traditional Chinese medicine (TCM) in the prevention and treatment of IDD. Results Current literature indicated that the PCD of NPCs was closely associated with the pathogenesis of IDD. Additionally, the development of targeted pharmaceuticals based on the mechanisms of PCD could effectively impede the loss of NPCs. Conclusion This review demonstrated that targeting the PCD of NPCs may be a promising strategy for the treatment of IDD.

We developed a contemporary cardioprotective medication using silver nanoparticles (AgNPs) loaded with Spinacia oleracea to treat isoproterenol (ISO)-induced myocardial infarction in mice, focusing on the PPAR-γ/NF-κB pathway. The physicochemical techniques, such as Fourier-transform infrared spectroscopy, field emission scanning electron microscopy, ultraviolet–visible spectroscopy, and energy dispersive X-ray analysis, were employed to characterize the AgNPs. In the in vivo experiment, myocardial infarction was induced in mice by administering ISO subcutaneously at a dose of 40 mg/kg every 12 h for a total of three times. The mice were divided into five groups in a random manner: (1 and 2) ISO + AgNPs at varying doses (10 and 20 μg/mL) and time points; (3) ISO; and (4) control. Following the treatment, cardiac function was assessed through electrocardiogram, as well as biochemical and histochemical analyses. In the study, we examined the inflammatory reactions and cell death in human coronary artery endothelial cells exposed to lipopolysaccharide (LPS). The PPAR-γ/NF-κB activation by LPS and the resulting cytokine production were checked using real-time PCR and western blot techniques. The typical ST segment depression in myocardial infarction mice is significantly inhibited by the administration of AgNPs. Additionally, the treatment with AgNPs leads to a significant improvement in ventricular wall infarction, a decrease in mortality rate, and inhibition of myocardial injury marker levels. Furthermore, the application of AgNPs resulted in a decrease in the inflammatory environment within the hearts of mice with myocardial infarction. This effectively prevented the increase in TNF-α, IL-1β, and IL-6. The gene expression normalization of PPAR-γ/NF-κB/IκB-α/IKKα/β and PPAR-γ phosphorylation could potentially be linked to the advantageous impacts of AgNPs. In the context of an in vitro experiment, the administration of AgNPs demonstrated a notable decrease in cell death and inflammation cytokines expression inhibition. The myocardial infarction mice in the pre + post-ISO group appear to experience more noticeable cardioprotective effects from the treatment with AgNPs than those in the post-ISO group. Our research findings demonstrate that AgNPs possess cardioprotective efficacies in ISO-induced myocardial infarction. This beneficial effect may be attributed to the PPAR-γ activation and the NF-κB signaling inhibition. Consequently, our study presents a novel remedial approach for myocardial infarction treatment in clinical settings.

Abstract Background Malassezia restricta, a lipophilic and lipodependent yeast belonging to the basidiomycetes group, is an opportunistic fungal pathogen associated with various skin diseases, including seborrheic dermatitis and dandruff. Typically, Malassezia infection in neonates manifests as fungemia or hematogenous dissemination to the bone or lungs. However, vertebral osteomyelitis caused by these fungi is rarely reported owing to non-specific clinical presentations and laboratory/imaging findings. The Pathogen Metagenomics Sequencing (PMseq) technique enables direct high-throughput sequencing of infected specimens, facilitating the rapid and accurate detection of all microorganisms in clinical samples through comprehensive reports. Case presentation A 52-year-old male was admitted to our hospital on July 20, 2022 with a 3-month history of ambulatory difficulties and localized low back pain. Magnetic Resonance Imaging (MRI) examination of the spinal column revealed irregular bone destruction affecting the L2, L3, and L5 vertebral bodies. Additionally, low T1 and high T2 intensity lesions were observed at the intervertebral discs between L3 and L5. The presumptive diagnosis of tuberculous spondylitis was made based on the imaging findings, despite negative results in all mycobacterium tests. However, the patient exhibited no improvement after receiving regular anti-tuberculosis treatment for 3 months. Subsequent MRI revealed an expansive abnormal signal within the vertebral body, leading to progressive bone destruction. The absence of spinal tuberculosis or other infective microorganisms was confirmed through culture from blood and pathological tissue from the L4 vertebral body. Subsequently, PMseq was performed on the specimens, revealing M. restricta as the predominant pathogen with the highest relative abundance value. The pathological examination revealed the presence of fungal mycelium in the L4 vertebral body, with positive findings on periodic Schiff-methenamine and periodic acid-Schiff staining. The anti-tuberculosis treatment was discontinued, and an antifungal combination of fluconazole and voriconazole was administered. All symptoms were resolved after 7 consecutive months of treatment, and the patient was able to ambulate autonomously. Vertebral lesions were reduced on MRI during the 13-month follow-up. Conclusions M. restricta is not a commonly recognized pathogen associated with infectious vertebral osteomyelitis. However, PMseq can aid in diagnosis, timely treatment, and decision making for some non-specific infectious diseases.

ObjectiveTo investigate the trends and significant determinants of delayed HIV diagnosis （DHD） among newly reported HIV/AIDS cases in Xuhui District， Shanghai between 2018 and 2022.MethodsIn the newly reported HIV/AIDS cases， patients died within one year without accident， HIV/AIDS cases with CD4 cell count