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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.

Soil caves collapse are typical geological hazards in karst areas. The disintegration of red clay is one of the important mechanisms leading to soil caves collapse. The pH of the soil pore solution has changed due to acid rains and the overuse of fertilizers. This study conducted disintegration tests to observe the disintegration rate of red clay in solutions with different pH values by a self-made disintegration apparatus. The inductively coupled plasma mass spectrometer (ICP-MS) and Zeta potential analyzer were used to test the cations concentration in the solutions and the electric potential (ζ potential) of red clay, analyzing the effect of pH on the physicochemical properties and the disintegration rate of red clay, providing a scientific basis for evaluating and preventing soil caves collapse. The results show that the disintegration rate in solutions with different pH values follows the order of pH = 11 > pH = 9 > pH = 3 > pH = 5 > pH = 7. When pH < 7, the cations concentration and the cations charges density in the soil solutions increased as the pH decreases. The electric potential changed from negative to positive as the pH decreases, with the potential value first decreasing and then increasing. When pH > 7, the cations concentration, cations charges density in the soil solutions, and the electric potential increased with the pH increased. The ratio of charges density to electric potential increased under both acidic and alkaline conditions, the thickness of the clay diffusion layer decreased, short-range gravitational decayed and repulsion increased, ultimately leading to the disintegration of red clay.

The effects of dietary emodin supplementation on the growth, gut health, and gut microbiota of common carp (Cyprinus carpio) were evaluated in this study. The basal diet (CONTROL group) was supplemented with 5 g/kg (EMODIN 5 group), 10 g/kg (EMODIN 10 group) and 20 g/kg (EMODIN 20 group) emodin for 6 weeks. Compared with the CONTROL alone group, the EMODIN 10 and EMODIN 20 groups of common carp had a significantly increased weight gain rate (WG%), specific growth rate (SGR%), and condition factor ratio (CF%) and decreased feed conversion ratio (FCR). The activities of intestinal digestive enzymes, including α-amylase (AMS), protease (PRT) and lipase (LPS), were also significantly increased in the emodin group (EMODIN 10 and EMODIN 20). Emodin also enhanced intestinal barrier function by increasing the length of intestinal villi, the number of goblet cells, and expression of the occludin gene. The dominant gut probiotics Cetobacterium and Actinobacteriota_unclassified were significantly enriched in the emodin group, while Aeromonas abundance was depleted, indicating that the intestinal barrier health of the emodin-treated carp improved. We also observed elevated alanine aminotransferase (ALT), aspartate aminotransferase (AST), catalase (CAT) and superoxide dismutase (T-SOD) activities, and malondialdehyde (MDA) levels were reduced in the serum of the treatment group, which means that the fish's immunity was improved. There was functional enrichment of gut microbiota immune system pathways in the emodin group, which highlights the importance of gut immunity. Network pharmacology analysis showed that the NF-κB signaling pathway was significantly enriched in the intestine-immunity axis. Accordingly, RTPCR showed that emodin affected the intestinal expression of NF-κB signaling pathway-related immune factors in artificially infected fish, including decreased NF-κB, IL-6 and TNF-α expression and increased TLR22 expression. Correlation analysis showed that downregulated NF-κB expression upon emodin addition (EMODIN 20) was related to increased Cetobacterium abundance. Therefore, dietary emodin supplementation may enhance intestinal immune defense by regulating the intestinal microbiota, which promotes common carp growth.

Abstract Oxidative stress, as a characteristic of cellular aerobic metabolism, plays a crucial regulatory role in the development and metastasis of gastric cancer (GC). Long noncoding RNAs (lncRNAs) are important regulators in GC development. However, research on the prognostic patterns of oxidative stress-related lncRNAs (OSRLs) and their functions in the immune microenvironment is currently insufficient. We identified the OSRLs signature (DIP2A-IT1, DUXAP8, TP53TG1, SNHG5, AC091057.1, AL355001.1, ARRDC1-AS1, and COLCA1) from 185 oxidative stress-related genes in The Cancer Genome Atlas (TCGA) cohort via random survival forest and Cox analyses, and the results were subsequently validated in the Gene Expression Omnibus (GEO) dataset. The patients were divided into high- and low-risk groups by the risk score of the OSRLs signature. Longer overall survival was detected in the low-risk group than in the high-risk group in both the TCGA cohort (P 1, P = 0.005), and time-dependent receiver operating characteristic (ROC) curve analysis and nomogram analysis were utilized to evaluate the predictive ability of the risk model. Next, gene set enrichment analysis revealed that the immune-related pathway, Wnt/ $$\upbeta$$ β -catenin signature, mammalian target of rapamycin complex 1 signature, and cytokine‒cytokine receptor interaction was enriched. High-risk patients were more responsive to CD200, TNFSF4, TNFSF9, and BTNL2 immune checkpoint blockade. The results of qRT‒PCR further proved the accuracy of our bioinformatic analysis. Overall, our study identified a novel OSRLs signature that can serve as a promising biomarker and prognostic indicator, which provides a personalized predictive approach for patient prognosis evaluation and treatment.

Guilin is a famous karst area, and currently the view that the disintegration of red clay will cause soil cave collapse is increasingly recognized. In order to study the influence of the coupling effect of moisture content and void ratio on the disintegration of red clay, different moisture contents and void ratios of Guilin red clay were placed on a self-made disintegration apparatus to record the real-time disintegration amount and observe the disintegration phenomenon. Images of the structural characteristics of soil were obtained by a scanning electron microscope (SEM). Additionally, nuclear magnetic resonance (NMR) was applied to analyze the distribution of water in both natural and saturated states. The results show that the disintegration rate of red clay decreases as the initial moisture content increases, but increases with the increase of void ratio. Both moisture content and void ratio affect the structural characteristics of red clay. When the moisture content remains constant, the soil changes from a three-peak to a two-peak structure as the void ratio increases. The total area and secondary peak area of the T2 spectrum increase, while the starting T2 value of the main peak shifts to the right and the area decreases. Meanwhile, the starting T2 value of the secondary peak shifts to the right and the area increases. When the void ratio remains constant, the starting T2 value of the main peak gradually shifts to the left and the area decreases as the moisture content increases. However, the starting T2 value of the secondary peak shifts to the right and the area decreases or first decreases and then increases. The disintegration rate does not exhibit a significant relationship with either pore volume or macropore volume. The combined water saturation shows a bilinear relationship with both the moisture content and void ratio, where it increases as the initial moisture content increases, but decreases as the void ratio increases, with a correlation coefficient of 0.9929. The disintegration rate has an exponential relationship with the combined water saturation, and it decreases as the combined water saturation increases, with a correlation coefficient of 0.9934.

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.

To understand the performance of ecological pervious concrete prepared with mixed sandstone/limestone aggregates, limestone and sandstone were used as two aggregates. The sandstone-to-limestone volume ratio was calculated in 0 : 1, 0.25 : 0.75, 0.5 : 0.5, 0.75 : 0.25, and 1 : 0 in coarse aggregate to prepare ecological pervious concrete specimens. The compressive test, water permeability test, cooling test, evaporation test, alkaline test, and scanning electron microscope (SEM) tests were carried out with qualified compressive strength as the indicator to determine the optimum sandstone-to-limestone volume ratio for the ecological pervious concrete. The results show that the water permeability, cooling property, and evaporation property of the ecological pervious concrete increase with the sandstone content. When the sandstone-to-limestone volume ratio is less than 0.32 : 0.68 (the substitution rate of sandstone for limestone in ecological pervious concrete is 32%), the strength of ecological pervious concrete meets the requirements of 5 MPa and achieves the best permeability coefficient of 9 mm/s. This realizes the full use of net water storage and cooling capacity of the ecological pervious concrete and makes the ecological pervious concrete meet the construction requirement of slope protection in sponge cities in the south.

To explore the effect and applicability of contour reverse slope terraces in water and soil conservation of karstic red clay soil area in northern Guangxi, rainfall simulation experiments were conducted on bare red clay soil slopes laid with contour reverse slope terraces to find the erosion pattern in response to different rainfall intensities (15, 30, and 50 mm/h) and bedrock porosities (1%, 3%, and 5%). The results showed that contour reverse slope terraces can change the spatial distribution of surface runoff, divert surface runoff to the underground, and increase underground sediment yielding. It is found that contour reverse slope terraces can effectively reduce surface soil erosion though it still remains dominant erosion for red clay terraced farmland, with surface runoff reduced by 71%, 52%, and 46% and surface sediment loss reduced by 70%, 65%, and 63%, respectively, when the rainfall intensity is set at 15 mm/h, 30 mm/h, and 50 mm/h. It is concluded that contour reverse slope terraces can help reduce water and soil erosion of red clay terraced farmland in northern Guangxi.

As a prominent component of the construction field of sponge cities, ecological concrete is an essential tool to reach the goals of green, low-carbon living and sustainable development. A quantitative summary of the preliminary research on ecological concrete infrastructure in sponge city architecture is needed. Therefore, CiteSpace and VOSviewer were applied to perform a comparative analysis of the number of papers, countries, institutions, core authors, literature co-citations, research hotspots, and future trends in ecological concrete in the sponge city construction industry. The results show that the number of papers on ecological concrete is increasing, the research collaboration between domestic and foreign authors is relatively single, and there is insufficient interdisciplinary integration between institutions and the phenomenon of “relatively independent research.” The number of papers published in the field of ecological concrete construction has been on the rise, reaching more than 100 in each of the last 10 years, with China and the United States contributing more to the scientific output of the field. To meet the needs of global environmental protection and resource conservation, the theme of “promoting comprehensive resource conservation and recycling” will continue in the future, making concrete a feature of green, low-carbon, sustainable development and other areas of environmental protection in the construction field.

Abstract The hepatic stellate cells (HSCs) activation by myofibroblastic differentiation is critical for liver fibrosis. Crosstalk between stromal cells and tumor cells in the microenvironment alters the properties and facilitates the growth and metastasis of tumor cells. How mechanical stimuli originally stiffness of extracellular matrix (ECM) contribute to tumor development remains poorly understood. Here, we demonstrated that stiffness contributes to mechanosignal transduction in HSCs, which promotes hepatocellular carcinoma (HCC) cells growth and metastasis through secretion of FGF2. On stiffness matrix, HSCs activation was confirmed by immunofluorescence (IF) and Western blot (WB) for α-smooth muscle actin (SMA). Increasing matrix stiffness promoted HSCs activation by CD36-AKT-E2F3 mechanosignaling through shRNA-mediated E2F3 knockdown, AKT inhibitors, and CD36 shRNA. Moreover, ChIP-qPCR. Confirmed that E2F3 combined the promoter of FGF2, and stiffness promoted FGF2 expression. On a stiff matrix, HCC cells cultured with conditioned media (CM) from HSCs increased HCC cells growth and metastasis by binding FGFR1 to activate PI3K/AKT and MEK/ERK signaling pathways. Moreover, conditional E2F3 knockout mice were subjected to CCl4 treatment to assess the role of E2F3 in HSC activation. Additionally, the DEN-induced HCC model was also used to evaluate the role of E2F3 in liver fibrosis and HCC growth. In conclusion, we demonstrated that stiffness-induced HSC activation by E2F3 dependent. Stiffness activated CD36-AKT-E2F3 signaling and targeted FGF2 transcription, subsequently, activated HCC growth and metastasis by FGFR1-mediated PI3K/AKT and MEK/ERK signaling.

The unconfined compressive strength of specimens with three moisture contents and three NaOH/TMG ratios (sodium hydroxide mass/solid mass, where solid contains tungsten tailings, metakaolin and commercial geopolymer) cured at 60–100 ℃ for seven days was conducted to investigate the temperature effect and action mechanism of tungsten tailings strength activated by NaOH. The test results of the scanning electron microscope (SEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR) were adopted to analyze the micro characteristics of the mixture under different curing temperatures. The test results indicate that the unconfined compressive strength of tungsten tailings activated by NaOH increases first and then decreases with the increase of curing temperature, and reaches the maximum at 90 ℃. C(N)-A-S-H gels mixed with poly-sialate (PS) and poly-sialate-siloxo (PSS) types are generated at different proportions at different temperatures activated by NaOH. The relative content of PS type gels increases when the curing temperature rises from 60 ℃ to 90 ℃, and decreases when the temperature continues to rise to 100 ℃. The greater the total amount of gel and the relative content of PS-type gel, the greater the strength of the specimens. In this study, the unconfined compressive strength is strongest in the temperature of 90 ℃. It was the optimal curing temperature. The minimum and the maximum strengths were 12.4 MPa and 42.8 MPa when the curing temperature is over or equal to 70 ℃, which meets the strength requirements of building bricks of MU10. In conclusion, the research results provide scientific basis and references for the resource utilization of tungsten tailings.

In engineering practice, properly characterizing the spatial distribution of soil liquefaction potential and induced surface settlement is essential for seismic hazard assessment and mitigation. However, geotechnical site investigations (e.g., cone penetration test (CPT)) usually provide limited and sparse data with high accuracy. Geophysical surveys provide abundant two-dimensional (2D) data, yet their accuracy is lower than that of geotechnical investigations. Moreover, correlating geotechnical and geophysical data can effectively reduce site investigation costs. This study proposes a data-driven adaptive fusion sampling strategy that automatically develops an assessment model of the spatial distribution of soil liquefaction potential from spatially sparse geotechnical data, performs monitoring of liquefaction-induced settlement, and integrates spatiotemporally unconstrained geophysical data to update the model systematically and quantitatively. The proposed strategy is illustrated using real data, and the results indicate that the proposed strategy overcomes the difficulty of generating high-resolution spatial distributions of liquefaction potential from sparse geotechnical data, enables more accurate judgment of settlement variations in local areas, and is an effective tool for site liquefaction hazard analysis.

The undrained shear strength of clay is an important index for the calculation of the bearing capacity of the foundation soil, the calculation of the soil pressure of the foundation pit, and the analysis of the slope stability. Therefore, the purpose of this paper is to conduct a comprehensive study of the combined use of machine learning with clay theoretical equations to estimate it. Under the Bayesian framework, the CatBoost algorithm (CatBoost–Bayesian) based on Bayesian optimization algorithm was developed to obtain the feature importance level of soil parameters affecting the undrained shear strength of clay, so as to adaptively couple the theoretical equation of undrained shear strength of K0 consolidated clay, which was derived from the modified Cambridge model. Then, the theoretical equation of undrained shear strength of the isotropically consolidated clay was established from the critical state of the clay parameters. Finally, it was illustrated and verified using the experimental samples of Finnish clay. The results indicate that the theoretical equation established by the overconsolidation ratio and effective overburden pressure parameters can well estimate the undrained shear strength of isotropically consolidated clays, and the parameter uncertainty can be considered explicitly and rigorously.

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1186/s13046-018-0717-3

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1186/s13046-019-1188-x.