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Objective To determine the effect of enamel matrix derivative (EMD) on remineralization of artificial root dentin caries. Methods Bovine root dentin blocks were placed in a demineralization solution to create artificial root dentin carious lesions. The lesions were then randomly divided into EMD group (30 g/L EMD, the experimental group), sodium fluoride (NaF) aqueous solution group (1 g/L NaF, the positive control group) and distilled and deionised water (DDW) group (the negative control group), and all the lesions were pH-cycled at 6 cycles per day for 8 d. Morphology of the lesions were observed by scanning electron microscopy (SEM) and polarized light microscopy (PLM). Transverse microradiography (TMR) was used to examine mineral loss, lesion depth and mineral content. Results After pH-cycling, the surface morphology by SEM and the vertical morphology by PLM suggested that EMD and NaF treatment, but not DDW, caused mineral accumulation of artificial root dentin caries. Meanwhile, TMR revealed significantly lower mineral loss, shallower lesion depth and more mineral content in the EMD group than the DDW group (P < 0.05) after pH-cycling. Conclusion EMD can significantly promote remineralization of root dentin caries in vitro, and is a promising agent for non-invasive root caries therapy. [Key words] enamel matrix derivative , root caries , root dentin ,remineralization ,

Abstract Stroke, the second leading cause of death and disability, causes massive cell death in the brain followed by secondary inflammatory injury initiated by disease associated molecular patterns released from dead cells. Nonetheless, the evidence regarding the causal relationship between inflammatory cytokines and stroke subtypes is obscure. To leverage large scale genetic association data to investigate the interplay between circulating cytokines and stroke, we adopted a two-sample bi-directional Mendelian randomization (MR) analysis. Firstly, we performed a forward MR analysis to examine the associations of genetically determined 31 cytokines with 6 stroke subtypes. Secondly, we conducted a reverse MR analysis to check the associations of 6 stroke subtypes with 31 cytokines. In the forward MR analysis, genetic evidence suggests that 21 cytokines were significantly associated with certain stroke subtype risk with |β| ranging from 1.90 × 10−4 to 0.74. In the reverse MR analysis, our results found that five stroke subtypes (intracerebral hemorrhage (ICH), large artery atherosclerosis ischemic stroke (LAAS), lacunar stroke (LS), cardioembolic ischemic stroke (CEI), small-vessel ischemic stroke (SV)) caused significantly changes in 16 cytokines with |β| ranging from 1.08 × 10−4 to 0.69. In particular, those five stroke subtypes were statistically significantly associated with C-reactive protein (CRP). In addition, ICH, LAAS, LS and SV were significantly correlated with vascular endothelial growth factor (VEGF), while LAAS, LS, CEI and SV were significantly related to fibroblast growth factor (FGF). Moreover, integrated bi-directional MR analysis, these factors (IL-3Rα, IL-6R, IL-6Rα, IL-1Ra, insulin-like growth factor-1(IGF-1), IL-12Rβ2) can be used as predictors of some specific stroke subtypes. As well as, IL-16 and C–C motif chemokine receptor 7 (CCR7) can be used as prognostic factors of stroke. Our findings prognostic identify potential pharmacological opportunities, including perturbation of circulating cytokines for both predicting stroke risk and post stroke treatment effects. As we conducted a comprehensive search and analysis of stroke subtype and cytokines in the existing publicly available GWAS database, the results have good population-generalizability.

Avoiding the upward-bending hook is a highly pressing and challenging task in the field of similar aluminum alloys friction stir lap welding (FSLW). To enhance formation quality and then obtain the welded lap joint with high tensile shear load, a novel impacting flow FSLW (IF-FSLW) process based on the X-shape reverse-threaded pin was proposed in this study. Three welding tools with different tool geometry parameters were developed to analyze how the locations of the materials accumulated zone (MAZ) influenced the joint formation and the joint loading capacity, and 7B04 aluminum alloys were chosen as research subject. Results showed that the horizontally-impacting and vertically-impacting effects of MAZ on and above the original lap interface made the hook respectively present the forky structure at the end and the downward-bending morphology, and the horizontally-impacting effect of MAZ made the stir zone (SZ) have a protruding morphology near the MAZ. Under the tensile fracture mode, the IF-FSLW joint under configuration A had a greatly heightened tensile shear load under the combined actions of the downward-bending hook and the enlarged SZ. The tensile shear load of IF-FSLW joint reached 8.62 kN/mm under the reasonable combination of tool geometry parameters and welding process parameters. The IF-FSLW process by the X-shape reverse-threaded pin provides an effective way to obtain a superb-strength lap joint of aluminum alloys.

In order to clarify the controlling effect of different packaging materials on common storage pests, the penetration and survival of 7 kinds of high density polyethylene films with different concentrations of deltamethrin by the larvae of 3 common species of stored grain pests (Tribolium castaneum (Herbst), Tribolium confusum Duval and Lasioderma serricorne (Fabricius)) were investigated after being treated by two penetration methods for different times at 27~29 ℃ and 70%~80% RH. The results showed that all the tested new insect-proof films had certain insect resistance capabilities, which were different based on species of stored grain insects. In addition, the insect resistance capability of the 6 kinds of new films containing chemicals was higher than that of the control films after 9 days of treatment, and the anti-penetration rate of 1% A (HDPE particle containing 5% deltamethrin by mass) film, 3% A film, 1% B (HDPE particle containing 5% deltamethrin and 2% isoethers by mass) film and 3% B film was 100% under two penetration modes. The survival rate of all three species larvae decreased with increasing treatment time. After 9 days of parallel penetration treatment, the survival rate of three species of larvae on 3%B film was significantly lower than that of other films, and the survival rate of L. serricorne larvae reduced to 10% at the lowest. According to the penetration resistance and larvae survival rate of the test insects on the films, 3% B film had the best insect control effectiveness.

A semiconductor nanomaterial was prepared and its degradation efficiency on zearalenone (ZEN) was investigated. The photocatalytic material, graphitic carbon nitride (g-C3N4), was synthesized by the conventional thermal cracking method, and its structure was analyzed by (X-ray diffraction) XRD, Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The photocatalytic degradation experiments showed that g-C3N4 induced photocatalytic effects under ultraviolet light (254 nm, including 185 nm), releasing reactive oxygen radicals to degrade ZEN. The experimental conditions for the photocatalytic degradation of ZEN were explored. The results showed that the degradation rate of ZEN was 96.0% when the mass of the photocatalytic material , the wavelength of the UV lamp, the initial concentration and the irradiation time were 20 mg, 254 nm (50 W), 0.5 μg/mL and 60 min, respectively. Meanwhile, the experimental conditions for the photocatalytic degradation of ZEN powder samples were optimized. The results showed that the degradation rate of ZEN was 80.0% when the mass of the photocatalytic material, the wavelength of the UV lamp, and the irradiation time were 800 mg, 254 nm (50 W) and 50 min, respectively. The results could provide a theoretical reference and practical basis for the photocatalytic degradation of ZEN.

Herein, we elucidate the potential role of ANO6 (TMEM16F) in gastrointestinal stromal tumors (GISTs). ANO6 expression in GIST and adjacent normal tissues was determined using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blotting. Cell proliferation, apoptosis, and pyroptosis were examined utilizing 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, terminal deoxynucleotidyl transferase dUTP Nick-End Labeling staining, and flow cytometry. In addition, the total iron and Fe2+ levels were assessed. IL-18 and IL-1β levels were also evaluated. Lipid reactive oxygen species (ROS), cystine (Cys), glutathione (GSH), and glutathione peroxidase 4 (GPX4) levels were evaluated using appropriate kits. Ferroptotic markers, including Ptgs2, Chac1, SLC7A11, and SLC3A2, were analyzed by RT-qPCR, western blotting, and immunohistochemistry. ANO6 expression decreased in GIST tissues. ANO6-plasmid inhibits proliferation, induces apoptosis, and promotes pyroptosis in GIST-T1 and GIST-T1 IR cells. The ANO6-plasmid induced ferroptosis, as confirmed by enhanced lipid ROS levels, increased intracellular concentrations of total iron and Fe2+, promoted Ptgs2 and Chac1 expression, reduced Cys, GSH, and GPX4 levels, and downregulated SLC7A11 and SLC3A2 expression after in vitro and in vivo treatment with ANO6-plasmid. Moreover, the ANO6-plasmid inhibited GIST growth in vivo. Therefore, ANO6 may be a promising therapeutic target for blocking the development of GIST via the induction of apoptosis, pyroptosis, and ferroptosis.

Characterizing the dynamic mechanical properties of spinal cord tissue is deemed important for developing a comprehensive knowledge of the mechanisms underlying spinal cord injury. However, complex viscoelastic properties are vastly underexplored due to the spinal cord shows heterogeneous properties. To investigate regional differences in the biomechanical properties of spinal cord, we provide a mechanical characterization method (i.e., dynamic mechanical analysis) that facilitates robust measurement of spinal cord ex vivo, at small deformations, in the dynamic regimes. Load-unload cycles were applied to the tissue surface at sinusoidal frequencies of 0.05, 0.10, 0.50 and 1.00 Hz ex vivo within 2 h post mortem. We report the main response features (e.g., nonlinearities, rate dependencies, hysteresis and conditioning) of spinal cord tissue dependent on anatomical origin, and quantify the viscoelastic properties through the measurement of peak force, moduli, and hysteresis and energy loss. For all three anatomical areas (cervical, thoracic, and lumbar spinal cord tissues), the compound, storage, and loss moduli responded similarly to increasing strain rates. Notably, the complex modulus values of ex vivo spinal cord tissue rose nonlinearly with rising test frequency. Additionally, at every strain rate, it was shown that the tissue in the thoracic spinal cord was significantly more rigid than the tissue in the cervical or lumbar spinal cord, with compound modulus values roughly 1.5-times that of the lumbar region. At strain rates between 0.05 and 0.50 Hz, tan δ values for thoracic (that is, 0.26, 0.25, 0.06, respectively) and lumbar (that is, 0.27, 0.25, 0.07, respectively) spinal cord regions were similar, respectively, which were higher than cervical (that is, 0.21, 0.21, 0.04, respectively) region. The conditioning effects tend to be greater at relative higher deformation rates. Interestingly, no marked difference of conditioning ratios is observed among all three anatomical regions, regardless of loading rate. These findings lay a foundation for further comparison between healthy and diseased spinal cord to the future development of spinal cord scaffold and helps to advance our knowledge of neuroscience.

Fusarium infection of wheat can lead to scab, mycotoxin contamination and yield reduction. Fusarium is a serious threat to food security. In this study, the Fusarium strains in wheat were isolated and identified. The three strains N1, N2 and N3 belonged to Fusarium graminearum, Fusarium asiaticum and Fusarium culmatum, respectively. The production of zearalenone, vomitoxin and fumonisin by the three strains was analyzed by toxin-producing gene detection and mycotoxin detection. The results showed that N1 and N3 could produce zearalenone and vomitoxin, but did not produce fumonisin, while N2 did not produce these three toxins. In this study, ozone and chlorine dioxide were further used for gas fumigation to explore the effect of gas fumigation on the three strains isolated. By observing the spore morphology, mycelium length and mycelium morphology, the results showed that chlorine dioxide fumigation could effectively inhibit the growth of mycelium and spore germination, while ozone could only inhibit spore germination and had no obvious inhibitory effect on the growth of mycelium.

Rapid and accurate determination of pigment content is important for quality inspection of spinach leaves during storage. This study aimed to use hyperspectral imaging at two spectral ranges (visible/near-infrared, VNIR: 400–1000 nm; NIR: 900–1700 nm) to simultaneously determine the pigment (chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids) content in spinach stored at different durations and conditions (unpackaged and packaged). Partial least squares (PLS), back propagation neural network (BPNN) and convolutional neural network (CNN) were used to establish single-task and multi-task regression models. Single-task CNN (STCNN) models and multi-task CNN (MTCNN) models obtained better performances than the other models. The models using VNIR spectra were superior to those using NIR spectra. The overall results indicated that hyperspectral imaging with multi-task learning could predict the quality attributes of spinach simultaneously for spinach quality inspection under various storage conditions. This research will guide food quality inspection by simultaneously inspecting multiple quality attributes.

Abstract Currently, there is a lack of effective treatments for spinal cord injury (SCI), a debilitating medical condition associated with enduring paralysis and irreversible neuronal damage. Extradural decompression of osseous as well as soft tissue components has historically been the principal objective of surgical procedures. Nevertheless, this particular surgical procedure fails to tackle the intradural compressive alterations that contribute to secondary SCI. Here, we propose an early intrathecal decompression strategy and evaluate its role on function outcome, tissue sparing, inflammation, and tissue stiffness after SCI. Durotomy surgery significantly promoted recovery of hindlimb locomotor function in an open‐field test. Radiological analysis suggested that lesion size and tissue edema were significantly reduced in animals that received durotomy. Relative to the group with laminectomy alone, the animals treated with a durotomy had decreased cavitation, scar formation, and inflammatory responses at 4 weeks after SCI. An examination of the mechanical properties revealed that durotomy facilitated an expeditious restoration of the injured tissue's elastic rigidity. In general, early decompressive durotomy could serve as a significant strategy to mitigate the impairments caused by secondary injury and establish a more conducive microenvironment for prospective cellular or biomaterial transplantation.

Summary: Uropathogenic Escherichia coli (UPEC) is the most common causative agent of urinary tract infection (UTI). UPEC invades bladder epithelial cells (BECs) via fusiform vesicles, escapes into the cytosol, and establishes biofilm-like intracellular bacterial communities (IBCs). Nucleoside-diphosphate kinase (NDK) is secreted by pathogenic bacteria to enhance virulence. However, whether NDK is involved in UPEC pathogenesis remains unclear. Here, we find that the lack of ndk impairs the colonization of UPEC CFT073 in mouse bladders and kidneys owing to the impaired ability of UPEC to form IBCs. Furthermore, we demonstrate that NDK inhibits caspase-1-dependent pyroptosis by consuming extracellular ATP, preventing superficial BEC exfoliation, and promoting IBC formation. UPEC utilizes the reactive oxygen species (ROS) sensor OxyR to indirectly activate the regulator integration host factor, which then directly activates ndk expression in response to intracellular ROS. Here, we reveal a signaling transduction pathway that UPEC employs to inhibit superficial BEC exfoliation, thus facilitating acute UTI.

IntroductionPatient satisfaction is a crucial metric to gauge the quality of medical services, but the psychological factors influencing patient satisfaction remain insufficiently explored.MethodsThis study examines these psychological factors by applying the theory of bounded rationality to 1,442 inpatients in Hangzhou, China, whose data were collected using a questionnaire. One-way ANOVA, correlation analysis, and hierarchical regression were used to analyze patient satisfaction and its associated factors. Additionally, the path analysis of the structural equation model revealed the mechanisms behind the key psychological factors that influenced patient satisfaction.ResultsMedical risk perception, the social cognition of the medical environment, and social desirability bias had significant positive impacts on patient satisfaction. By contrast, negative emotions had a significant negative impact on patient satisfaction. Notably, patients’ negative emotions had both a suppressive effect and a positive moderating effect on the relationship between medical risk perception and patient satisfaction. Similarly, social desirability bias had a suppressive effect on the correlation between the social cognition of the medical environment and patient satisfaction, albeit with a negative moderating effect.DiscussionThese results suggest that when evaluating and improving patient satisfaction, accounting only for the factors that directly influence medical service quality is insufficient, as the indirect and moderating effects of patients’ negative emotions and the social cognition of the medical environment must also be considered. Medical service providers should thus address patients’ negative emotions, establish good doctor–patient relationships, optimize service environments, provide managers with medical risk education and training on negative emotions, and prioritize patient-centered care. Additionally, the government and relevant health departments should optimize medical policies, enhance fairness and accessibility, and create a positive social cognitive environment through public education and awareness campaigns.

BackgroundAbdominal aortic calcification (AAC) pathogenesis is intricately linked with inflammation. The pan-immune-inflammation value (PIV) emerges as a potential biomarker, offering reflection into systemic inflammatory states and assisting in the prognosis of diverse diseases. This research aimed to explore the association between PIV and AAC.MethodsEmploying data from the National Health and Nutrition Examination Survey (NHANES), this cross-sectional analysis harnessed weighted multivariable regression models to ascertain the relationship between PIV and AAC. Trend tests probed the evolving relationship among PIV quartiles and AAC. The study also incorporated subgroup analysis and interaction tests to determine associations within specific subpopulations. Additionally, the least absolute shrinkage and selection operator (LASSO) regression and multivariable logistic regression were used for characteristics selection to construct prediction model. Nomograms were used for visualization. The receiver operator characteristic (ROC) curve, calibration plot and decision curve analysis were applied for evaluate the predictive performance.ResultsFrom the cohort of 3,047 participants, a distinct positive correlation was observed between PIV and AAC. Subsequent to full adjustments, a 100-unit increment in PIV linked to an elevation of 0.055 points in the AAC score (β=0.055, 95% CI: 0.014-0.095). Categorizing PIV into quartiles revealed an ascending trend: as PIV quartiles increased, AAC scores surged (β values in Quartile 2, Quartile 3, and Quartile 4: 0.122, 0.437, and 0.658 respectively; P for trend

High spatial resolution (HSR) remote sensing imagery presents a rich tapestry of foreground-background intricacies, rendering semantic segmentation in aerial contexts a formidable and vital undertaking. At its core, this challenge revolves around two pivotal questions: 1) Mitigating Background Interference and Enhancing Foreground Clarity. 2) Accurate Segmentation in Dense Small Object Cluster. Conventional semantic segmentation methods primarily cater to the segmentation of large-scale objects in natural scenes, yet they often falter when confronted with aerial imagery’s characteristic traits such as vast background areas, diminutive foreground objects, and densely clustered targets. In response, we propose a novel semantic segmentation framework tailored to overcome these obstacles. To address the first challenge, we leverage PointFlow modules in tandem with the Foreground-Scene (F-S) module. PointFlow modules act as a barrier against extraneous background information, while the F-S module fosters a symbiotic relationship between the scene and foreground, enhancing clarity. For the second challenge, we adopt a dual-branch structure termed disentangled learning, comprising Foreground Precedence Estimation and Small Object Edge Alignment (SOEA). Our foreground saliency guided loss optimally directs the training process by prioritizing foreground examples and challenging background instances. Extensive experimentation on the iSAID and Vaihingen datasets validates the efficacy of our approach. Not only does our method surpass prevailing generic semantic segmentation techniques, but it also outperforms state-of-the-art remote sensing segmentation methods.

At present, in the assembly building construction practice, the relevant subjects lack the concept of building quality management and awareness of responsibility, and the rights and duties of the subjects of each link are not clear in the division of responsibility for building quality. In this paper, based on the deep confidence network, for the problem that the accuracy of the traditional DBN model will gradually decrease, a genetic algorithm is introduced to optimize the conventional restricted Morzmann machine, and the number of nodes in the hidden layer of the genetic algorithm optimization DBN node number process is obtained after the improvement. The optimal method for planning building quality assessment is selected based on the comparison results of the established DBN algorithm function. Then, the optimal building quality assessment model is constructed. Then design the evaluation index system for quality influencing factors and verify it with structural equations. Finally, the model is used to quantify the degree of influence of assembly building quality. The study concludes that all path coefficients affecting the quality of assembled buildings are greater than 0.5, the P-value is less than 0.001, and the five proposed hypotheses are all valid. In the assessment of the quality of residential projects, the final results of excellent, good, moderate, and qualified accounted for 0.1952, 0.2299, 0.3086, and 0.2663, respectively, and the quality of the project’s construction was evaluated as a good grade. This study provides a new method for improving the awareness of quality responsibility among relevant subjects in the construction industry and guaranteeing the level of building quality.

In this paper, the principles, algorithms and different linear regression models are sorted out and finalized to determine the multiple linear regression model suitable for this study. The different types of regression are synthesized through the elastic net algorithm. Based on the multiple linear regression model, students’ performance in language, mathematics and English was used as the dependent variable Y on behalf of academic performance, and five sports such as physical education and hygiene were used as the independent variable X, to carry out an empirical study on 3,800 students. From this, it was concluded that the contribution rates affecting language achievement were sports attitude, environment, and hygiene in the order of coefficients of 0.548, 0.312, and −0.266. In contrast, exercise habit [B=−0.032, t=−1.574, P=0.116] and sports knowledge [B=0.027, t=1.561, P=0.119] did not pass the test of significance. The contribution of influencing math achievement was in the order of sports environment and attitude with coefficients of 0.402 and 0.327, which were positively correlated with math achievement Y2. The contribution rate affecting English achievement is in the order of sports hygiene, sports attitude and exercise habit, and their coefficients are 0.398, 0.295 and 0.124, all of which are positively correlated with English achievement Y3.

Objective: Pulmonary infection (PI), a severe complication of immunosuppressive therapy, affects patients’ prognosis. As part of this study, we aimed to construct a pulmonary infection prediction (PIP) model and validate it in patients receiving immunosuppressive drugs (ISDs).Methods: Totally, 7,977 patients being treated with ISDs were randomised 7:3 to the developing (n = 5,583) versus validation datasets (n = 2,394). Our predictive nomogram was established using the least absolute shrinkage and selection operator (LASSO) and multivariate COX regression analyses. With the use of the concordance index (C-index) and calibration curve, the prediction performance of the final model was evaluated.Results: Among the patients taking immunosuppressive medication, PI was observed in 548 (6.9%). The median time of PI occurrence after immunosuppressive therapy was 123.0 (interquartile range: 63.0, 436.0) days. Thirteen statistically significant independent predictors (sex, age, hypertension, DM, malignant tumour, use of biologics, use of CNIs, use of methylprednisolone at 500 mg, use of methylprednisolone at 40 mg, use of methylprednisolone at 40 mg total dose, use of oral glucocorticoids, albumin level, and haemoglobin level) were screened using the LASSO algorithm and multivariate COX regression analysis. The PIP model built on these features performed reasonably well, with the developing C-index of 0.87 (sensitivity: 85.4%; specificity: 81.0%) and validation C-indices of 0.837, 0.829, 0.832 and 0.830 for predicting 90-, 180-, 270- and 360-day PI probability, respectively. The decision curve analysis (DCA) and calibration curves displayed excellent clinical utility and calibration performance of the nomogram.Conclusion: The PIP model presented herein could aid in the prediction of PI risk in individual patients who receive immunosuppressive treatment and help personalise clinical decision-making.

This study investigates the impact of residue soil (RS) powder on the 3D printability of geopolymer composites based on fly ash and ground granulated blast furnace slag. RS is incorporated into the geopolymer mixture, with its inclusion ranging from 0% to 110% of the combined mass of fly ash and finely ground blast furnace slag. Seven groups of geopolymers were designed and tested for their flowability, setting time, rheology, open time, extrudability, shape retention, buildability, and mechanical properties. The results showed that with the increase in RS content, the fluidity of geopolymer mortar decreases, and the setting time increases first and then decreases. The static yield stress, dynamic yield stress, and apparent viscosity of geopolymer mortar increase with the increase in RS content. For an RS content between 10% and 90%, the corresponding fluidity is above 145 mm, and the yield stress is controlled within the range of 2800 Pa, which meets the requirements of extrusion molding. Except for RS-110, geopolymer mortars with other RS contents showed good extrudability and shape retention. The compressive strength of 3D printing samples of geopolymer mortar containing RS has obvious anisotropy.

Over the past few years, many scholars began to study averaging principles for fractional stochastic differential equations since they can provide an approximate analytical method to reduce such systems. However, in the most previous studies, there is a misunderstanding of the standard form of fractional stochastic differential equations, which consequently causes the wrong estimation of the convergence rate. In this note, we take fractional stochastic differential equations with Lévy noise as an example to clarify these two issues. The corrections herein have no effect on the main proofs except the two points mentioned above. The innovation of this paper lies in three aspects: (i) the standard form of the fractional stochastic differential equations is derived under natural time scale; (ii) it is first proved that the convergence interval and rate are related to the fractional order; and (iii) the presented results contain and improve some well known research achievements.

In order to deepen the understanding of the occurrence mechanism and water vapor transport characteristics of the heavy rain process in the extreme arid region of Xinjiang, a rare heavy rain process in the Tarim Basin during the period of 18–22 July 2021 was comprehensively analyzed by using multi-source data. The results show that the upper tropospheric South Asian high was distributed in a “west-high-east-low” pattern during the rainstorm process, and the rainstorm area was located on the right side of the upper jet stream entrance area, while the middle-level Iranian high pressure, Baikal high pressure and Central Asian low pressure formed a “two-highs and one-low” circulation situation. The coupling of the high and low air jets and the strong vertical upward motion provided favorable dynamic conditions. Rainstorm water vapor mainly comes from the Mediterranean Sea, Central Asia and the Indian Ocean, and it enters the basin in four paths: west, east to west, west to east, and southwest and south. The water vapor mainly flows into the middle layer of the western boundary and the southern boundary and the lower layer of the eastern boundary, and it flows out from the middle and upper layer of the eastern boundary. The negative moist potential vorticity region at a low level has a strong indicator significance for the occurrence and development of heavy rain, and the superposition of positive and negative moist potential vorticity regions at vertical height is conducive to the occurrence and development of heavy rain.