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This paper focuses on the effect of fiber orientation on the resistance of seepage-induced erosion in fiber-reinforced sand. To clarify the discrepancy and mechanism of different-oriented fibers improving the resistance of the sand matrix, a series of DEM-Darcy coupling simulations were conducted. The microscopic parameters of fiber-reinforced sand were confirmed by the rigorous calibration procedure. The fibers perpendicular to the seepage direction were found to increase the difficulty of moving fluid through the specimen and significantly reduce the erosion rate of the specimen. These macroscopic behaviors acquired corresponding explanations at the mesoscopic scale, including the evolution of fiber-sand contact orientation, coordination number, average normal contact force, tensile force, and energy dissipation. According to the simulation results, it is found that the highest proportion of tensile force in perpendicular fibers can reach 80%, while the parallel fibers are only 40%, which indicates that the perpendicular fibers have a significant netting effect. The mesoscopic behaviors reasonably revealed the role of the fibers with different orientations on the sand matrix during the seepage. This study is beneficial for further understanding the mechanical behaviors of fiber-reinforced sand under seepage-induced erosion in safety engineering. [ABSTRACT FROM AUTHOR]

Turfy soil is a special soil with numerous undecomposed plant fibers and humus, which can be considered a soil-fiber mixture. In this paper, the macro-mesoscopic dynamic responses of turfy soil subjected to multilevel cyclic loading with different waveforms (triangular, square, sinusoidal) were investigated employing the discrete element method (DEM). The microscopic parameters of the DEM model were confirmed by laboratory tests and calibration procedures. The hysteresis between the applied and measured stress on the loading plates was discussed to determine the appropriate frequency before simulation. Macroscopically, the discrepancies, including the velocity of the loading plates, the deformation of the specimen, and sample size effect were investigated under these three waveform loadings. Microscopically, the differences in energy, coordination number, average normal contact force between pure and turfy soil, internal force alternation and bending degree of fibers in turfy soil were studied to disclose the discrepancies in macroscopic behaviors with different waveforms. Simulation results illustrate that square waveforms can excite the support of the soil matrix by plant fibers in turfy soil to a greater extent. This study is beneficial for further understanding the mechanical behaviors of soil-fiber mixtures under the action of different forms of cyclic loads in safety engineering. [ABSTRACT FROM AUTHOR]

Background: Analyzing the neuronal organizational structures and studying the changes in the behavior of the organism is key to understanding cognitive functions of the brain. Although some studies have indicated that spatiotemporal firing patterns of neuronal populations have a certain relationship with the behavioral responses, the issues of whether there are any relationships between the functional networks comprised of these cortical neurons and behavioral tasks and whether it is possible to take advantage of these networks to predict correct and incorrect outcomes of single trials of animals are still unresolved. Methodology/Principal Findings: This paper presents a new method of analyzing the structures of whole-recorded neuronal functional networks (WNFNs) and local neuronal circuit groups (LNCGs). The activity of these neurons was recorded in several rats. The rats performed two different behavioral tasks, the Y-maze task and the U-maze task. Using the results of the assessment of the WNFNs and LNCGs, this paper describes a realization procedure for predicting the behavioral outcomes of single trials. The methodology consists of four main parts: construction of WNFNs from recorded neuronal spike trains, partitioning the WNFNs into the optimal LNCGs using social community analysis, unsupervised clustering of all trials from each dataset into two different clusters, and predicting the behavioral outcomes of single trials. The results show that WNFNs and LNCGs correlate with the behavior of the animal. The U-maze datasets show higher accuracy for unsupervised clustering results than those from the Y-maze task, and these datasets can be used to predict behavioral responses effectively. Conclusions/Significance: The results of the present study suggest that a methodology proposed in this paper is suitable for analysis of the characteristics of neuronal functional networks and the prediction of rat behavior. These types of structures in cortical ensemble activity may be critical to information representation during the execution of behavior. [ABSTRACT FROM AUTHOR]

Excessive exposure to Ultraviolet (UV) rays can cause premature skin aging. Ishigoside (IGS) is a new glyceroglycolipid compound isolated from brown algal Ishige okamurae , However, whether it can protect the skin from (Ultraviolet-B) UVB damage has not been illuminated. The in vitro anti -photoaging effect of IGS was conducted in UVB-induced HaCaT. The HaCaT cells were divided into the following five groups: (1) cells didn't suffer from UVB irradiation or IGS treatment. (2–5) Cells were treated with various concentrations of IGS (0, 10, 50, and 100 μ M) and irradiated by 40 mJ/cm2 UVB. The Matrix metalloproteinase (MMP) of photoaging process was determined by ELISA kits and the latent interaction between IGS and MMP was further performed by molecular docking. The crucial signaling pathway proteins involved in the collagen synthesis and degradation were subsequently evaluated by Western blotting, immunofluorescence and EMSA. IGS effectively suppresses the high expressions and secretions of matrix metalloproteinases (MMPs) and photo-inflammation by blocking MAPKs, AP-1 and NF-κB. Meanwhile, increasing antioxidant enzyme expression. Molecular docking results suggest that inhibition of IGS on MMPs may be attributed to its hydrogen supply and hydrophobic capacity. In addition, IGS enhanced procollagen production by upregulating the TGF-β/Smad pathways. IGS exhibited anti -photoaging activity in UVB-damage HaCaT. These effects might be a contribution by its suppression of MMPs expression via MAPKs, AP-1 and NF-κB pathway and have anti-oxidative and anti-inflammatory effects. Therefore, IGS has the great potential to become skin-care products or functional foods for preventing skin photoaging. [Display omitted] • Ishigoside is the functional ingredient of edible brown algae Ishige Okamurae. • Photoprotectant ishigoside has the potential to develop into healthy food. • Ishigoside reduced matrix metalloproteinases expression and alleviate inflammation via affecting the MAPK/AP-1 and NF-κB pathways. • Ishigoside can inhibitory binding with MMPs by molecular docking analysis. [ABSTRACT FROM AUTHOR]

Alcoholic liver disease (ALD) threatens human health, so it is imperative that we find ways to prevent or treat it. In recent years, the study of polysaccharides has shown that they have different kinds of bioactivities. Among them are many biological effects that have been attributed to polysaccharide precursors. D-Isofloridoside (DIF) is one of the polysaccharide precursors from the marine red alga Laurencia undulata. This study evaluated the effect of DIF on alcohol-induced oxidative stress in human hepatoma cells (HepG2). As a result, DIF attenuated alcohol-induced cytotoxicity, reduced the amount of intracellular reactive oxygen species (ROS), and effectively reduced alcohol-induced DNA damage in HepG2 cells. In addition, a western blot showed that, after DIF treatment, the expression levels of glutathione (GSH), superoxide dismutase (SOD), and B-cell lymphoma-2 (bcl-2) increased, while the expression levels of γ-glutamyl transferase (GGT), BCL2-associated X (bax), cleaved caspase-3, and mitogen-activated protein kinase (p38 and c-Jun N-terminal kinase) signal transduction proteins reduced. This showed that DIF may protect cells by reducing the amount of intracellular ROS and inhibiting intracellular oxidative stress and apoptotic processes. Finally, molecular docking demonstrated that DIF can bind to SOD, GGT, B-cell lymphoma-2, and bax proteins. These results indicated that DIF can protect HepG2 cells from alcohol-induced oxidative stress damage, making it an effective potential ingredient in functional foods. [ABSTRACT FROM AUTHOR]

Zinc indium sulfide (ZnIn2S4), as a significant visible-light-responsive photocatalyst, has become a research hotspot to tackle energy demand and environmental issues owing to its excellent properties of high stability, easy fabrication, and remarkable catalytic activity. However, its drawbacks, including low utilization of solar light and fast photoinduced charge carriers, limit its applications. Promoting the response for near-infrared (NIR) light (~52% solar light) of ZnIn2S4-based photocatalysts is the primary challenge to overcome. In this review, various modulation strategies of ZnIn2S4 have been described, which include hybrid with narrow optical gap materials, bandgap engineering, up-conversion materials, and surface plasmon materials for enhanced NIR photocatalytic performance in the applications of hydrogen evolution, pollutants purification, and CO2 reduction. In addition, the synthesis methods and mechanisms of NIR light-driven ZnIn2S4-based photocatalysts are summarized. Finally, this review presents perspectives for future development of efficient NIR photon conversion of ZnIn2S4-based photocatalysts. [ABSTRACT FROM AUTHOR]

As emerging pollutants, pharmaceutical and personal care products (PPCPs) have received extensive attention due to their high detection frequency (with concentrations ranging from ng/L to μg/L) and potential risk to aqueous environments and human health. Advanced oxidation processes (AOPs) are effective techniques for the removal of PPCPs from water environments. In AOPs, different types of free radicals (HO·, SO4·−, O2·−, etc.) are generated to decompose PPCPs into non-toxic and small-molecule compounds, finally leading to the decomposition of PPCPs. This review systematically summarizes the features of various AOPs and the removal of PPCPs by different free radicals. The operation conditions and comprehensive performance of different types of free radicals are summarized, and the reaction mechanisms are further revealed. This review will provide a quick understanding of AOPs for later researchers. [ABSTRACT FROM AUTHOR]

Livestock-polluted water is a pressing water environmental issue in plateau pastoral regions, necessitating the adoption of eco-friendly solutions. Despite periphyton being a promising alternative, its efficacy is limited by the prevalence of intense ultraviolet radiation, particularly ultraviolet-B (UVB), in these regions. Therefore, this study employs molecular tools and small-scale trials to explore the crucial role of indole-3-acetic acid (IAA) in modulating periphyton characteristics and mediating nutrient removal from livestock-polluted water under UVB exposure. The results revealed that IAA augments periphyton's resilience to UVB stress through several pathways, including increasing periphyton's biomass, producing more extracellular polymeric substances (EPS), and enhancing antioxidant enzyme activities and photosynthetic activity of periphyton. Moreover, IAA addition increased periphyton's bacterial diversity, reshaped bacterial community structure, enhanced community stability, and elevated the R2 value of neutral processes in bacterial assembly from 0.257 to 0.651 under UVB. Practically, an IAA concentration of 50 mg/L was recommended. Small-scale trials confirmed the effectiveness of IAA in assisting UVB-stressed periphyton to remove nitrogen and phosphorus from livestock-polluted water, without the risk of nitrogen accumulation. These findings offer valuable insights into the protection of aquatic ecosystems in plateau pastoral regions based on periphyton property in an eco-friendly manner. [Display omitted] • An eco-friendly technology to purify plateau livestock-polluted water was reported. • IAA improved physiological-biochemical properties of periphyton under UVB. • IAA optimized bacterial composition, structure, and function in periphyton under UVB. • Periphyton with added IAA purified livestock-polluted water well in a small trial. [ABSTRACT FROM AUTHOR]

Soil washing with green eluent is an efficient technique to remediate heavy metal contaminated farmland. In addition to eluent, less is known about the roles of accompanying ions on heavy metal removal. We investigated the effects of accompanying ions including Fe3+, Mn2+, Ca2+, Mg2+, Al3+, Si4+ and PO 4 3− on the desorption of Pb2+ and Cd2+ in paddy and arid soils using ethylenediaminetetraacetic acid and polyepoxysuccinic acid as eluents. The release rates of target and accompanying ions showed significant fast and slow reaction stages based on corresponding analysis and kinetic models. In fast reaction stage, Pb2+ and Cd2+ performed geochemical analogy with Ca2+, Mg2+ and PO 4 3−. The release curves of these ions were fitted well with Elovich model, indicating that they released from oxysalt surface into solution via ion exchange, and dissolution of Fe/Mn/Al/Si (hydr)oxides through H+- and ligand-promoted dissolution. In slow reaction stage, Pb2+ and Cd2+ were related to Fe3+, Mn2+, Al3+ and Si4+, which were controlled by intraparticle diffusion process. H+ slowly diffused into interlayer of phyllosilicates to displace target and accompanying ions by ion exchange. Therefore, this research filled the gap of accompanying ions driving the release behavior of heavy metal ions during leaching. [Display omitted] • Fast-slow reaction stages of ions were indicated by correspondence analysis. • Pb2+ and Cd2+ have geochemical analogy with Ca2+, Mg2+, PO 4 3− in fast reaction stage. • Pb2+ and Cd2+ fast released from soil oxysalt surface and dissolution of (hydr)oxide. • H+ entered phyllosilicate interlayer to displace target ions and Fe3+/Mn2+/Al3+/Si4+. [ABSTRACT FROM AUTHOR]

The unfrozen water content (ω u) is an important parameter affecting the hydrothermal-mechanical characteristics of soil and is of important significance with regard to engineering construction and environmental effects in cold regions. In this study, a widely-distributed special humus soil called turfy soil, with poor engineering geological properties, from seasonally frozen regions of northeastern China was investigated. Soil fundamental properties were determined, and ω u under various temperatures during a freeze–thaw process was measured by the nuclear magnetic resonance (NMR) method. Based on NMR theory and transverse relaxation time (T 2) distribution curves, two thresholds were determined to divide the types of pore water in soil. Soil freezing characteristic curves (SFCC) of the total and pore water were drawn, and changes in the internal microstructure and pore characteristics of the soil during the freeze–thaw process were analyzed. The results showed that a drastic phase change within the soil occurs during −2 °C to −4 °C, and the freezing process can be divided into three stages. The formation of small pores and the connection of large pores make the soil looser after freeze–thaw. The division of pore water and variation in ω u show that freezing starts from large pores, while thawing starts from small pores. The capillary water content significantly decreases after freeze–thaw, and the bulk water content tends to increase. At freezing Stage I, ω u is closely related to the initial properties of the soil, whereas ω u at −3 °C almost determines the value of ω u during subsequent freeze–thaw. Finally, a ω u -power function for turfy soil was proposed, and good fitting results were obtained for both freezing and thawing soil. This work can serve as the basis of studies on soil with high organic matter content as well as soil unfrozen water content during freeze–thaw cycles in cold regions. • Two T 2 cutoffs were determined to identify the pore water types of turfy soil. • Capillary water within turfy soil decreased significantly after freeze–thaw. • Pores formed and larger pores connected due to frost heaving after freeze–thaw. • ω u after drastic phase change affected ω u during the freeze–thaw process. • ω u parameterization considering of turfy soil properties showed good effects. [ABSTRACT FROM AUTHOR]

Converting solar energy into hydrogen production is a promising approach to tackle the energy crisis. However, developing excellent photocatalytic materials with properties of positive visible light response, high efficiency and photostability remain a great challenge. Herein, we developed a one-photon excitation path system by coupling 3D ZnIn 2 S 4 micro-flowers with 0D CoS 2 nanoparticles for hydrogen evolution, with an optimal hydrogen evolution rate of 22.24 mmol h−1 g−1. The systematic characterizations and DFT calculations disclose that the improved performance is ascribed to the construction of 0D/3D with multi-reflection and exposed reaction sites, as well as the incorporation of CoS 2 and ZIS via a one-photon excitation pathway, achieving the acceleration of photoinduced charge separation and transfer. This work shed light on the design of 0D/3D photocatalysts with high hydrogen evolution performance via a one-photon excitation pathway. [ABSTRACT FROM AUTHOR]