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Time-dependent consolidation behavior of unsaturated soils is a vital problem in the geotechnical engineering. With the aid of the Fredlund consolidation theory, this work further assumes the total stress of soils skeleton freely change, and extends the Fredlund consolidation theory to a Biot-type theory, establishing the fully-coupled equation model of multilayered unsaturated poroelastic media with transversely isotropic permeability. To convert the partial differential governing equation into ordinary differential equations, the integration transform technology is applied. Subsequently, the precise integration method is used to acquire the time-dependent consolidation solution of multilayered unsaturated media with transversely isotropic permeability in the transformed domain, which is further solved in the actual domain by the inverse Hankel transform. A verification examples is provided to compare the present results with the existing work in the literature, showing a great coincidence and proving the feasibility of the present solution. Finally, numerous numerical examples are presented to investigate the evolution of excess pore pressure and settlement under quasi-static loads, revealing the consolidation behavior of unsaturated soils. The results demonstrates that the ramping time, stratification, permeability, depth and m 1 w have a significant effect on the consolidation behavior. [ABSTRACT FROM AUTHOR]

Posttransplantation complications pose a major challenge to the long‐term survival and quality of life of organ transplant recipients. These complications encompass immune‐mediated complications, infectious complications, metabolic complications, and malignancies, with each type influenced by various risk factors and pathological mechanisms. The molecular mechanisms underlying posttransplantation complications involve a complex interplay of immunological, metabolic, and oncogenic processes, including innate and adaptive immune activation, immunosuppressant side effects, and viral reactivation. Here, we provide a comprehensive overview of the clinical features, risk factors, and molecular mechanisms of major posttransplantation complications. We systematically summarize the current understanding of the immunological basis of allograft rejection and graft‐versus‐host disease, the metabolic dysregulation associated with immunosuppressive agents, and the role of oncogenic viruses in posttransplantation malignancies. Furthermore, we discuss potential prevention and intervention strategies based on these mechanistic insights, highlighting the importance of optimizing immunosuppressive regimens, enhancing infection prophylaxis, and implementing targeted therapies. We also emphasize the need for future research to develop individualized complication control strategies under the guidance of precision medicine, ultimately improving the prognosis and quality of life of transplant recipients. [ABSTRACT FROM AUTHOR]

During strong earthquakes, pounding may occur on large-span bridges and their approach bridges. The effect and mitigation measures of such pounding have rarely been explored in previous studies. This paper primarily uses finite element models to investigate the pounding effects at the expansion joints between the main cable-stayed bridge and its approach bridge. Friction pendulum bearings (FPBs) and fluid viscous dampers (FVDs) are used to alleviate poundings. Furthermore, a detailed analysis is conducted on how the pounding effect of the isolated main bridge with FPBs and FVDs is affected by the wave passage effect, ground motion type, and soil type. This study reveals that FPBs and FVDs can effectively reduce pounding effects and the associated risks. Even with the installation of FPBs and FVDs, lower seismic wave velocities and near-fault seismic motions with pulse effects can significantly increase the pounding effects between the cable-stayed bridge and its approach bridge. [ABSTRACT FROM AUTHOR]

The article discusses the development of MASH-Ocean 1.0, an interactive platform that allows researchers to investigate microbial diversity, function, and biogeography using marine metagenomic data. The platform integrates global marine metagenomic data and provides various analysis modules for researchers studying hydrosphere ecosystems. These modules include diversity analysis, function analysis, biogeography analysis, and interaction network analysis. The platform allows users to visualize taxonomic composition, metabolic functional pathways, global distribution patterns of microbial species and genes, and microbial co-occurrence networks. The platform aims to provide a comprehensive and convenient service for researchers working with omics data from hydrosphere ecosystems. [Extracted from the article]

Aluminum foam-filled tubes are complicated structures created by filling one or more thin-walled metal tubes with varying shapes in cross-sections with aluminum foam. We optimized the structure of aluminum foam-filled tubes using software simulation, compression, and three-point bending experiments. Filling aluminum foam not only improves the axial compressive performance and bending strength of the thin-walled metal tube but also eliminates the disadvantage of the low strength of the aluminum foam. The aluminum foam-filled single tube exhibited significant improvements in load-bearing and energy absorption, with a one-time increase in load-bearing and five times increase in energy absorption compared with an empty tube. The aluminum foam-filled single tube with a smaller diameter-to-thickness ratio has a higher load-bearing capacity. In contrast, the length-to-diameter ratio has a lower impact on load-bearing capacity. Once the filling length reaches the effective filling length, the structure can still support higher loads and effectively reduce its overall weight. The compression and bending properties in the double-tube structure filled with foam aluminum improved significantly compared with the empty tube and single-tube structure filled with aluminum foam. The total compressive energy absorption capacity in the double-tube structure filled with aluminum foam is 2.01 times that of the empty tube and 1.81 times that in the single-tube-filled structure. When the wall thickness of the filled stainless steel tube is 1.0 mm, the total bending energy absorption and the specific absorption energy of the aluminum foam-filled double tube structure are 1.5 and 2.1 times that of the corresponding aluminum foam-filled single tube, respectively.

A quasi-equilibrium (QE) theoretical model is proposed to fit the slow dispersive electron relaxation of nano-TiO2 that occurs through the transfer to O2. The electron relaxation is obtained from measurement of photoinduced absorptions. By including both the traps with exponential and Gaussian distributions with respect to the energy, the electron relaxation is fully fitted with the QE model. A Monte Carlo simulation is also realized to fit the electron relaxation, which agrees well with the QE model. It is revealed that the kinetics of the electron transfer from TiO2 to O2 contains both contributions from the exponential and Gaussian traps. Their distributions are obtained from the QE model fitting. The dispersion factor of the exponential traps is ∼0.65 and the trap density is high. The Gaussian traps locate ∼0.4 eV below the conduction band and have narrow distribution. The density of the Gaussian traps is more than three orders of magnitude lower than that of the exponential traps. Despite the low density, the Gaussian traps have an important effect on the electron relaxation. The distributions of the thermal barriers for the electron relaxation are obtained for both relaxations contributed by the exponential and Gaussian traps, based on which the kinetics equations are proposed. The Gaussian trap contributed relaxation accords with mono-exponential kinetics, while the relaxation contributed from the exponential traps involves exponentially distributed weights. The apparent activation energy, kinetic time constants, and pre-exponential factor can be obtained. [ABSTRACT FROM AUTHOR]

On-line optical absorptions were monitored under steady light illuminations to study the electron relaxations happening through the transfer from nano-TiO2 to O2, which are found to be slow and dispersive. A quasi-equilibrium (QE) theory and Monte Carlo simulations are developed to model the electron transfer, and they give good fittings to the early stage electron relaxations (over 70%). It is shown that the electron QE population at traps is kept during the whole electron relaxations. The slow kinetics is attributed to both the low probability (ptr) for an electron transferring to an O2 from a trap and the multi-trapping transport. The dispersive feature is ascribed to the dynamic decrease in the quasi-Fermi level (EF). The electron transfer rate constants just after the termination of light illuminations are taken out from the QE model fittings to analyze the relaxation kinetics. It is found that O2 amounts mainly affect the electron transfer by changing ptr; light intensities and temperatures mainly affect the electron transfer by changing the multi-trapping transport. The difference between the conduction band edge and the EF is the thermal barrier of the electron transfer from TiO2 to O2. The apparent activation energy (Eapp) of the electron transfer, determined from the absorption decays measured at different temperatures, is smaller than the real thermal barrier because of the decrease of EF with temperatures. The disagreement between the simulations and the later stage relaxations is not caused by the none-QE electron distribution at deep traps, and additional deep traps with a different distribution should also contribute to the electron relaxations. [ABSTRACT FROM AUTHOR]