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Abstract We took the silt soil in the Yellow River flood area of Zhengzhou City as the research object and carried out triaxial shear and triaxial creep tests on silt soil with different moisture contents (8%, 10%, 12%, 14%) to analyze the effect of moisture content on silt soil. In addition, the influence of moisture contents on soil creep characteristics and long-term strength was analyzed. Based on the fractional derivative theory, we established a fractional derivative model that can effectively describe the creep characteristics of silt soil in all stages, and used the Levenberg–Marquardt algorithm to inversely identify the relevant parameters of the fractional derivative creep model. The results show that the shear strengths of silt soil samples with moisture contents of 8%, 10%, 12% and 14% are 294 kPa, 236 kPa, 179 kPa and 161 kPa, respectively. The shear strength of silt soil decreases with increasing moisture content. When the moisture content increases, the cohesion of the silt soil decreases. Under the same deviatoric stress, the higher the moisture content of the silt soil, the greater the deformation will be. The long-term strength of silt soil decreases exponentially with the increase of moisture content. If the moisture content is 12%, the long-term strength loss rate of silt soil is the smallest, with a value of 32.96%. The calculated values of our creep model based on fractional derivatives have a high goodness of fit with the experimental results. This indicates that our model can better simulate the creep characteristics of silt soil. This study can provide a theoretical basis for engineering construction and geological disaster prevention in silt soil areas in the Yellow River flood area.

In order to explore the creep characteristics of red clay under different pressures, the stress–strain curve and stress–strain–time curve of red clay under different pressures were obtained, and the triaxial shear and creep characteristics of red clay under different pressures were analysed. A triaxial shear test and creep test were carried out on red clay from Guilin as the research object under different pressures. The results show that: ➀ the cohesion and the angle of internal friction of red clay from Guilin, obtained from a triaxial shear test, are 57.20 kPa and 22.47°, respectively; ➁ according to the physical meaning of the parameters of the Burgers creep model, a simple and practical parameter inversion method is proposed, which can be used to obtain the parameters of the Burgers model for red clay under different perimeter pressures and differing deviatoric stress; and ➂ when comparing the calculation results with the test results, the correlation coefficients R2 of the two are above 0.9, with a good fitting effect, so the model can accurately describe the creep characteristics of red clay from Guilin. This study can provide a theoretical basis and technical support for engineering construction in the red clay area of Guilin.

Currently, most of the studies using optimization algorithms to mitigate the urban flooding problem have no more than three optimization objectives, and few of them take the operation status of the traditional drainage system as one of the optimization objectives, which is not conducive to the overall design of the city. This study proposes to mitigate the urban flooding problem by using a sponge-type comprehensive pipe corridor rainwater chamber. A four-objective optimization model is established by coupling the Storm Water Management Model (SWMM) and the Non-dominated Sorting Genetic Algorithm-III (NSGA-III), and two traditional drainage system state indicators (pipe overload time, node overflow volume), surface runoff coefficient, and total investment cost are selected as the optimization objectives for solving the problem. The results show that (1) the reduction rates of surface runoff coefficient, pipe overload time, and node overflow volume rate by the optimization model are 37.015–56.917%, 81.538–91.435%, and 51.578–84.963%, respectively; and the total investment cost is RMB 4.311–4.501 billion. (2) The effectiveness of combining SWMM and NSGA-III for an optimization solution is verified, and the relationship between the four objectives is explored. The study may provide useful information for urban flood control.

BackgroundAdvancements in radiotherapy (RT) technology have led to the prominence of precision RT in head and neck cancer (HNC) treatment. The new progress in precision RT offers more efficient therapy, potentially improving outcomes for HNC patients.ObjectiveThe present cross-sectional study aimed to assess the knowledge, attitude, and practice (KAP) of patients in advanced precision RT for HNC treatment.MethodsThis study enrolled HNC patients at the Affiliated Hospital of Hebei University of Engineering between October 2023 and May 2024. Then, the demographic data and KAP scores were collected using an investigator-designed questionnaire. Afterwards, descriptive statistics were provided for all study variables, and the relationship among KAP was analyzed using appropriate statistical tests, including Spearman correlation, logistic regression, and path analysis.ResultsA total of 436 participants with a mean age of 52.03 ± 12.19 years old were included. The mean knowledge score, attitude score, and practice score were 18.33 ± 4.21, 36.14 ± 1.71, and 26.26 ± 1.83, respectively. Although most of the participants were unfamiliar with advanced precision RT, they expressed a high willingness to follow their doctor's recommendation for this treatment. The multivariable analysis revealed a positive association between attitude score and proactive practice. The path analysis revealed that knowledge directly influenced attitude and practice, while attitude directly impacted practice.ConclusionHNC participants had poor knowledge of advanced precision RT techniques, but had a positive attitude and the willingness to undergo treatment when recommended by their physicians. These results suggest that improving patients' awareness for advanced precision RT can help to promote better attitude and advanced precision RT practice.

Osteosarcoma (OS) has strong invasiveness, early metastasis, high drug resistance, and poor prognosis. At present, OS still lacks reliable biomarkers, which makes early diagnosis of OS more difficult. AOC3 is highly expressed in OS and highly correlated with lung metastasis. qRT-PCR could identify mRNA levels of genes. Immunohistochemistry and Western blot assays could detect protein levels. Immunofluorescence and ELISA assays were applied to evaluate the activation of neutrophils. Additionally, transwell and wound healing assays evaluated cell migration and invasion abilities. Tube formation and sphere-forming assays were applied to detect the angiogenesis. C57BL/6 mice were injected with OS cells to establish a xenograft tumor model to observe the lung metastasis of OS. Flow cytometry is used to evaluate the ability of tumor cells to recruit neutrophils. AOC3 was significantly overexpressed in OS, and down-regulation of AOC3 could inhibit OS migration, invasion, and angiogenesis. AOC3 could increase tumor development and lung metastasis of OS in vivo experiments. The promoting effect of AOC3 on tumor lung metastasis was achieved by recruiting tumor neutrophils. Activated NETs could up-regulate the metastatic ability of OS cells. Tumor neovascularization also played a role in metastasis, and AOC3 supported tumor neovascularization. AOC3 accelerates lung metastasis of OS by recruiting tumor-related neutrophils and utilizing NETs and tumor vascularization formation.

The coronavirus disease 2019 (COVID-19) pandemic has imposed enormous morbidity and mortality burdens. Patients with rheumatic diseases (RDs) are vulnerable to the COVID-19 infection, given their immunocompromised status. Ensuring acceptance of the COVID-19 vaccine is important and has attracted attention by health professionals. In this study, we designed an online cross-sectional survey that used an online questionnaire from 8 May 2021 to 4 October 2021. Attitudes toward the COVID-19 vaccination, personal information, current disease activity status, adverse events (AEs), and knowledge sources of vaccines were collected. Descriptive statistics, nonparametric tests, and ordinal logistic regression were used to analyze the data. A total of 1022 questionnaires were received, among which 70.2% (720/1022) of patients with RDs agreed to vaccination, while only 31.6% of patients were actually vaccinated. Male, employed, high-income patients and those with inactive disease showed a more positive attitude. Concerns of AEs and disease flare were the main factors affecting vaccination willingness. Only 29.6% (304/1022) of patients thought they had received enough information about the COVID-19 vaccine from their doctors. In conclusion, most patients with RDs in China intended to get vaccinated, although the vaccination rate in this particular population was low. Rheumatologists should take more responsibility in COVID-19 vaccination education of patients with RDs.