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ABSTRACT A new simplified practical method for one‐dimensional nonlinear large‐strain consolidation of saturated homogenous soils is proposed. The derivation processes of the proposed method are introduced first, with a modification of Terzaghi's theory from a novel perspective to solve large‐strain consolidation problems. Verification checks of the proposed method with other solutions are then conducted. The proposed method is different from Lekha's solution because Lekha's analytical solution is based on the small strain theory. For linear consolidation, the proposed method shows excellent agreement with the Consolidation Settlement 2 (CS2) model. For nonlinear large‐strain consolidation, the new method is in good agreement with the CS2 model when Cc/Ck ≤ 1. After that, optimization of the proposed nonlinear solution is carried out for Cc/Ck > 1 with a more precise average constant coefficient of consolidation used in the simplified practical method, and good agreement is obtained between the solutions from the proposed method and the CS2 model. Overall, the proposed simplified method provides practical, reliable, and efficient solutions for analyzing linear and nonlinear large‐strain consolidation. [ABSTRACT FROM AUTHOR]

In the current context of urbanization, urban agglomerations face complex challenges in maintaining an ecological balance. This study uses remote sensing images of the Central Yunnan urban agglomeration from 2000 to 2020, along with socioeconomic data, to analyze the spatiotemporal characteristics of the green space evolution. Utilizing dynamic geographically weighted regression analysis based on principal components (PCA-GWR), we identify the key socioeconomic factors influencing these changes and quantitatively analyze the driving forces in each stage. Our findings reveal a continuing trend of decreasing total green space alongside increasing individual forest types and pronounced regional disparities in green space dynamics. The results indicate that socioeconomic factors exert both positive facilitative effects and negative pressures, with evident spatial and temporal variability. Urbanization and economic development promote forest expansion in certain areas, while contributing to the reduction in farmland and shrub–grass lands. Significant variations are influenced by factors such as the urbanization rate, the agricultural population, the industrial composition, and fiscal revenue. This study enhances the in-depth understanding of the relationship between the spatiotemporal dynamics of green spaces and socially driven mechanisms, offering significant insights for sustainable urban planning and landscape management and harmonizing urban agglomeration development. [ABSTRACT FROM AUTHOR]

Vacuum preloading via prefabricated horizontal drains (PHDs) is an efficient technique to accelerate the consolidation of dredged soft soils. However, this technique lacks a clear and concise theoretical solution to the PHD vacuum consolidation analysis for slurry. To address this issue, this study proposes a novel analytical solution based on a mathematical logical procedure. The governing equations are first derived based on square PHD consolidation unit cells given the assumption of equal strain, taking into account various drainage conditions at the boundaries and the horizontal and vertical spacings of PHD. A seepage direction coefficient, directly determined through PHD spacing without additional identification, is further introduced into the derived formulation to enhance the solution to be more consistent with the results of free strain consolidation analysis. Then, the proposed analytical solution is validated based on three laboratory and field tests. The proposed solution is successfully applied to estimate the consolidation behavior at a site in Aomori Prefecture, Japan, involving PHD vacuum preloading. All results demonstrate that the proposed analytical solution is applicable for the design and management of PHD vacuum preloading construction projects and practically useful for engineers. Furthermore, the influences of the large strain effect, variable hydraulic conductivity, and variable compressibility on the consolidation analysis are discussed. [ABSTRACT FROM AUTHOR]

Fiber-reinforced polymer (FRP)-confined concrete tubular columns have been extensively studied, where the design of the column is usually based on stiffness and strength. The ability to sustain large deformations without losing structural integrity is also critical in geotechnical engineering. This paper proposes a novel high-ductility tubular column incorporating glass fiber-reinforced polymer (GFRP). The exterior container of the column is a GFRP jacket, while the infill material is sand or cemented sand. Different specimens are prepared with different infill materials (i.e., sand and cemented sand), and the thickness of the GFRP jacket (i.e., 3 mm, 5 mm, and 7 mm). Axial compression tests are conducted to study the compressive behavior of this novel tubular column with two load types (i.e., load on infill and load on the tube). Optical Frequency Domain Reflectometry (OFDR) technique is adopted to monitor the hoop strain distributions along the height of the columns. Experimental results reveal that the presence of infill material could prevent buckling failure of the hollow tubes, while the confinement effect provided by the GFRP tube significantly enhances the bearing capacity and ductility of the infill material. The FRP-confined cemented sand column exhibits notably increased initial stiffness, but slightly decreased ductility and peak load in comparison to the sand-filled FRP column. With the increase in axial displacement, the stiffness of the infill sand core exceeds that of the cemented sand due to the compressive hardening behavior of the sand. Through the OFDR technique, the deformation profile of the column is precisely delineated, facilitating the assessment of the uniformity of the dilation behavior. Moreover, the analysis-oriented model is adopted to rationally predict the load-strain behavior of FRP-confined cemented sand columns. [ABSTRACT FROM AUTHOR]

The application of fiber-reinforced polymer (FRP) composites as piling materials in harsh environments has gained popularity due to their high corrosion resistance. FRP composites can be fabricated using different types of epoxy resin matrices and fibers. This study aims to investigate the interface behavior between sand and FRP materials with varying levels of hardness, with a particular emphasis on the abrasive surface wear of FRP. Monotonic interface shear tests (under normal stresses of 50, 100, 200, and 400 kPa) and interface shear tests repeated 20 times (under normal stresses of 200 and 400 kPa) are performed. The local surface roughness of the FRP plates is measured for tested samples under both monotonic and repeated loadings using laser scanning to evaluate the accumulated abrasion effect. The results of monotonic tests indicate that under a given shear displacement and normal stress, the samples with softer FRP plates exhibit higher interface friction angles and more pronounced dilative behavior. Following repeated tests, the interface friction angles of softer FRP specimens decrease, while the surface roughness of the FRP plates gradually increases. However, for the softest FRP plate, its surface is severely damaged after repeated tests under high normal stress levels, leading to unstable changes in the test results. [ABSTRACT FROM AUTHOR]

The accurate forecasting of provincial carbon emissions is pivotal for China as it strives to meet its carbon neutrality goals. To this end, an improved grey multivariable convolution model has been developed, employing a unified new-information-based method for the preliminary accumulation of data. The particle swarm optimization (PSO) algorithm is then applied to determine the optimal parameters within this sophisticated model. Moreover, to identify the relevant factors for provincial carbon emissions, a comprehensive determination of these factors was conducted from two aspects: literature research and grey relational analysis. For validation, carbon emission data from two provinces are analyzed, and the model's efficacy is thoroughly compared with five competitors across three different predictive horizons. The empirical results indicate that the proposed model has distinct advantages over the competing models. Additionally, the model's robustness and comprehensive forecasting abilities for provincial carbon emissions are confirmed through detailed Monte Carlo simulations and parameter sensitivity analyses across various forecasting horizons. [ABSTRACT FROM AUTHOR]

Preparing elastic substrates as a carrier for dual-end supported nickel chromium thin film strain sensors is crucial. Wet etching is a vital microfabrication process widely used in producing microelectronic components for various applications. This article combines lithography and wet etching methods to microprocess the external dimensions and rectangular grooves of 304 stainless steel substrates. The single-factor variable method was used to explore the influence mechanism of FeCl3, HCl, HNO3, and temperature on the etching rate, etching factor, and etching surface roughness. The optimal etching parameter combination was summarized: an FeCl3 concentration of 350 g/L, HCl concentration of 150 mL/L, HNO3 concentration of 100 mL/L, and temperature of 40 °C. In addition, by comparing the surface morphology, microstructure, and chemical and mechanical properties of a 304 stainless steel substrate before and after etching treatment, it can be seen that the height difference of the substrate surface before and after etching is between 160 μm and −70 μm, which is basically consistent with the initial design of 0.2 mm. The results of an XPS analysis and Raman spectroscopy analysis both indicate that the surface C content increases after etching, and the corrosion resistance of the surface after etching decreases. The nano-hardness after etching increased by 26.4% compared to before, and the ζ value decreased by 7%. The combined XPS and Raman results indicate that the changes in surface mechanical properties of 304 stainless steel substrates after etching are mainly caused by the formation of micro-nanostructures, grain boundary density, and dislocations after wet etching. Compared with the initial rectangular substrate, the strain of the I-shaped substrate after wet etching increased by 3.5–4 times. The results of this study provide the preliminary process parameters for the wet etching of a 304 stainless steel substrate of a strain measuring force sensor and have certain guiding significance for the realization of simple steps and low cost of 304 stainless steel substrate micro-nano-processing. [ABSTRACT FROM AUTHOR]

Objective: To determine the inhibitory effects of pachymic acid on lung adenocarcinoma (LUAD) cells and elucidate its underlying mechanism. Methods: CCK-8, wound healing, Transwell, Western blot, tube formation, and immunofluorescence assays were carried out to measure the effects of various concentrations of pachymic acid on LUAD cell proliferation, metastasis, angiogenesis as well as autophagy. Subsequently, molecular docking technology was used to detect the potential targeted binding association between pachymic acid and protein tyrosine phosphatase 1B (PTP1B). Moreover, PTP1B was overexpressed in A549 cells to detect the specific mechanisms of pachymic acid. Results: Pachymic acid suppressed LUAD cell viability, metastasis as well as angiogenesis while inducing cell autophagy. It also targeted PTP1B and lowered PTP1B expression. However, PTP1B overexpression reversed the effects of pachymic acid on metastasis, angiogenesis, and autophagy as well as the expression of Wnt3a and β-catenin in LUAD cells. Conclusions: Pachymic acid inhibits metastasis and angiogenesis, and promotes autophagy in LUAD cells by modulating the Wnt/ β-catenin signaling pathway via targeting PTP1B. [ABSTRACT FROM AUTHOR]

Shield tunnel backfill grouting is vital to stabilize tunnel settlement at a later stage; however, most shield tunnel backfill grouting designs lack a complete theoretical reference, and numerical simulations of the grouting process are rarely conducted. This study presents the fundamental theories of grout diffusion and pressure variation for backfill grouting during shield construction. Moreover, the numerical simulation methods coupled with discrete element methods (DEM) and finite difference methods (FDM) are achieved to simulate the process of grout injection from the grouting hole into the shield tail gap and generate grout pressure on the surrounding rock. The diffusion state of the grout in the shield tail gap and the squeezing effect on the surrounding rock under two shield tail disengagement modes are analyzed, as well as the impact of various grouting pressure on the surface settlement. The results indicated that the grout diffusion in the shield tail gap can be divided into three stages: the stage of diffusion with each grouting hole as the starting point, the stage of interconnection and contact of the grout injected in each grouting hole, and the final gap filling stage. Each of the three stages can be described using the proposed equation. During the grouting process, the grout is injected into the shield tail gap at a certain pressure, but the grout diffuses slowly to both sides and upwards, which causes a rapid rise of the principal stresses in the soil around the tunnel. After grouting is complete, the grout pressure gradually dissipates and stabilizes, and the principal stress decreases. In addition, backfill grouting can reduce surface settlement, but it does not affect its distribution width. [ABSTRACT FROM AUTHOR]

Introduction: The generation of an HIV-1 vaccine able to induce long-lasting protective immunity remains a main challenge. Here, we aimed to modify nextgeneration soluble, prefusion-stabilized, close-to-native, glycan-engineered clade C gp140 envelope (Env) trimers (sC23v4 KIKO and ConCv5 KIKO) for optimal display on the cell surface following homologous or heterologous vector delivery. Methods: A combination of the following modifications scored best regarding the preservation of closed, native-like Env trimer conformation and antigenicity when using a panel of selected broadly neutralizing (bnAb) and non-neutralizing (nnAb) monoclonal antibodies for flow cytometry: i) replacing the natural cleavage site with a native flexible linker and introducing a single amino acid substitution to prevent CD4 binding (*), ii) fusing a heterologous VSV-G-derived transmembrane moiety to the gp140 C-terminus, and iii) deleting six residues proximal to the membrane. Results: When delivering membrane-tethered sC23v4 KIKO* and ConCv5 KIKO* via DNA, VSV-GP, and NYVAC vectors, the two native-like Env trimers provide differential antigenicity profiles. Whereas such patterns were largely consistent among the different vectors for either Env trimer, the membrane-tethered ConCv5 KIKO* trimer adopted a more closed and native-like structure than sC23v4 KIKO*. In immunized mice, VSV-GP and NYVAC vectors expressing the membranetethered ConCv5 KIKO* administered in prime/boost combination were the most effective regimens for the priming of Env-specific CD4 T cells among all tested combinations. The subsequent booster administration of trimeric ConCv5 KIKO* Env protein preserved the T cell activation levels between groups. The evaluation of the HIV-1-specific humoral responses induced in the different immunization groups after protein boosts showed that the various prime/boost protocols elicited broad and potent antibody responses, preferentially of a Th1-associated IgG2a subclass, and that the obtained antibody levels remained high at the memory phase. Discussion: In summary, we provide a feasible strategy to display multiple copies of native-like Env trimers on the cell surface, which translates into efficient priming of sustained CD4+ T cell responses after vector delivery as well as broad, potent, and sustained antibody responses following booster immunizations with the homologous, prefusion-stabilized, close-to-native ConCv5 KIKO* gp140 Env trimer. [ABSTRACT FROM AUTHOR]