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Objective To explore the protective effects and the underlying mechanisms of bone marrow mesenchymal stem cells (BMSCs) on the brain in microgravity environment. Methods The physiological effects of microgravity were simulated with the hindlimb unloading (HU) mouse model. The animals were divided into 3 groups: the control group (wild-type mice), the hindlimb unloading (HU) group, and the BMSCs treatment group, with six in each. RT-qPCR was adopted to determine the expression levels of pro-inflammatory cytokines (Il-6, Il-1β and Tnf-α) in the cerebral cortex; immunohistochemistry was performed to evaluate the proportions of microglia (IBA-positive) and astrocytes (GFAP-positive); Western blot was used to measure the expression levels of apoptosis-and senescence-related molecules (BAX, BCL-2, p21, and p53). Results Compared with wild-type mice, the expression levels of Il-6, Il-1β and Tnf-α in the cerebral cortex of HU mice were significantly increased (P＜0.05), the expression level of BAX, p21 and p53 was also significantly increased(P＜0.05). However, the expression level of BCL-2 protein were significantly decreased (P＜0.05). The proportion of microglia (IBA1 positive) and astrocytes (GFAP positive) was increased (P＜0.05); After BMSCs treatment, the expression level of Il-1β in the cerebral cortex of HU mice was significantly decreased (P＜0.05), the expression levels of BAX, p21 and p53 were significantly decreased (P＜0.05), and the expression level of BCL-2 protein was significantly increased (P＜0.05). The proportion of microglia (IBA1 positive) and astrocytes (GFAP positive) decreased (P＜0.05). Conclusions BMSCs potentially relieve the detrimental effects of simulated microgravity on mouse brain by inhibiting inflammation, apoptosis and cellular senescence.

Fe nanoparticle-functionalized ordered mesoporous carbon (Fe0/OMC) was synthesized using triblock copolymers as templates and through solvent evaporation self-assembly, followed by a carbothermal reduction. Fe0/OMC had three microstructures of two-dimensional hexagonal (space group, p6mm, Fe0/OMC-1), body centered cubic (Im3̄m, Fe0/OMC-2), and face centered cubic (Fm3̄m, Fe0/OMC-3) which were controlled by simply adjusting the template. All Fe0/OMC displayed paramagnetic characteristics, with a maximum saturation magnetization of 50.1 emu·g−1. This high magnetization is advantageous for the swift extraction of the adsorbent from the solution following the adsorption process. Fe0/OMC was used as an adsorbent for the removal of silver ions (Ag(i)) from aqueous solutions, and the adsorption capacity of Fe0/OMC-1 was enhanced by the functionalization of Fe0. Adsorption property of Fe0/OMC-1 was significantly higher than that of Fe0/OMC-2 and Fe0/OMC-3, indicating that the long and straight ordered pore channels were more favorable for adsorption, and the adsorption capacity of Ag(i) on Fe0/OMC-1 was 233 mg·g−1. The adsorption process exhibited conformity with both the pseudo-second-order kinetic model and the Freundlich model, suggesting that the dominant mechanism of adsorption involved multilayer adsorption on heterogeneous surfaces.

Geopolymer foam concrete (GFC), an emerging thermal insulation material known for its environmentally friendly and low-carbon attributes, has gained prominence for its use in bolstering building energy efficiency. A critical challenge in GFC production is foam destabilization by the alkaline environment in which foam is supersaturated with salt. In this study, GFC was prepared by using triterpene saponin (TS), sodium dodecyl sulphate (SDS), and cetyltrimethylammonium bromide (CTAB) as blowing agents, with fly ash as the precursor and calcium carbide slag (CA) combined with Glauber's salt (GS, Na2SO4 ≥ 99%) as the activator. The effect of GFC on mechanical properties was analyzed by examining its fluidity, pore structure, dry density, and compressive strength. The results show that TS has a stable liquid film capable of adapting to the adverse effects of salt supersaturation and alkaline environments. TS is highly stable in the GFC matrix, and so the corresponding pore size is small, and the connectivity is low in the hardened GFC. In addition, the hydration products of GFC exhibit different morphologies depending on the surfactant used. TS has better water retention due to hydrogen bonding, which facilitates the hydration process. [ABSTRACT FROM AUTHOR]

Enzymatically derived selenium-enriched peptides from Cardamine violifolia (CV) can serve as valuable selenium supplements. However, the industrial application of free enzyme is impeded by its limited stability and reusability. Herein, this study explores the application of co-immobilized enzymes (Alcalase and Dispase) on amino resin for hydrolyzing CV proteins to produce selenium-enriched peptides. The successful enzyme immobilization was confirmed through scanning electron microscopy (SEM), energy dispersive X-ray (EDX), and Fourier-transform infrared spectroscopy (FTIR). Co-immobilized enzyme at a mass ratio of 5:1 (Alcalase/Dispase) exhibited the smallest pore size (7.065 nm) and highest activity (41 U/mg), resulting in a high degree of hydrolysis of CV protein (27.2%), which was obviously higher than the case of using free enzymes (20.7%) or immobilized Alcalase (25.8%). In addition, after a month of storage, the co-immobilized enzyme still retained a viability level of 41.93%, showing fairly good stability. Encouragingly, the selenium-enriched peptides from co-immobilized enzyme hydrolysis exhibited uniform distribution of selenium forms, complete amino acid fractions and homogeneous distribution of molecular weight, confirming the practicality of using co-immobilized enzymes for CV protein hydrolysis. [ABSTRACT FROM AUTHOR]

Organic-inorganic hybrid perovskites have electronic and optoelectronic properties that make them appealing in many device applications.sup.1-4. Although many approaches focus on polycrystalline materials.sup.5-7, single-crystal hybrid perovskites show improved carrier transport and enhanced stability over their polycrystalline counterparts, due to their orientation-dependent transport behaviour.sup.8-10 and lower defect concentrations.sup.11,12. However, the fabrication of single-crystal hybrid perovskites, and controlling their morphology and composition, are challenging.sup.12. Here we report a solution-based lithography-assisted epitaxial-growth-and-transfer method for fabricating single-crystal hybrid perovskites on arbitrary substrates, with precise control of their thickness (from about 600 nanometres to about 100 micrometres), area (continuous thin films up to about 5.5 centimetres by 5.5 centimetres), and composition gradient in the thickness direction (for example, from methylammonium lead iodide, MAPbI.sub.3, to MAPb.sub.0.5Sn.sub.0.5I.sub.3). The transferred single-crystal hybrid perovskites are of comparable quality to those directly grown on epitaxial substrates, and are mechanically flexible depending on the thickness. Lead-tin gradient alloying allows the formation of a graded electronic bandgap, which increases the carrier mobility and impedes carrier recombination. Devices based on these single-crystal hybrid perovskites show not only high stability against various degradation factors but also good performance (for example, solar cells based on lead-tin-gradient structures with an average efficiency of 18.77 per cent). A solution-based lithography-assisted epitaxial-growth-and-transfer method is used to fabricate single-crystal hybrid perovskites on any surface, with precise control of the thickness, area and chemical composition gradient., Author(s): Yusheng Lei [sup.1] , Yimu Chen [sup.1] , Ruiqi Zhang [sup.1] , Yuheng Li [sup.1] , Qizhang Yan [sup.1] , Seunghyun Lee [sup.2] , Yugang Yu [sup.3] , Hsinhan [...]

Strain engineering is a powerful tool with which to enhance semiconductor device performance.sup.1,2. Halide perovskites have shown great promise in device applications owing to their remarkable electronic and optoelectronic properties.sup.3-5. Although applying strain to halide perovskites has been frequently attempted, including using hydrostatic pressurization.sup.6-8, electrostriction.sup.9, annealing.sup.10-12, van der Waals force.sup.13, thermal expansion mismatch.sup.14, and heat-induced substrate phase transition.sup.15, the controllable and device-compatible strain engineering of halide perovskites by chemical epitaxy remains a challenge, owing to the absence of suitable lattice-mismatched epitaxial substrates. Here we report the strained epitaxial growth of halide perovskite single-crystal thin films on lattice-mismatched halide perovskite substrates. We investigated strain engineering of [alpha]-formamidinium lead iodide ([alpha]-FAPbI.sub.3) using both experimental techniques and theoretical calculations. By tailoring the substrate composition--and therefore its lattice parameter--a compressive strain as high as 2.4 per cent is applied to the epitaxial [alpha]-FAPbI.sub.3 thin film. We demonstrate that this strain effectively changes the crystal structure, reduces the bandgap and increases the hole mobility of [alpha]-FAPbI.sub.3. Strained epitaxy is also shown to have a substantial stabilization effect on the [alpha]-FAPbI.sub.3 phase owing to the synergistic effects of epitaxial stabilization and strain neutralization. As an example, strain engineering is applied to enhance the performance of an [alpha]-FAPbI.sub.3-based photodetector. A method of deposition of mixed-cation hybrid perovskite films as lattice-mismatched substrates for an [alpha]-FAPbI.sub.3 film is described, giving strains of up to 2.4 per cent while also stabilizing the metastable [alpha]-FAPbI.sub.3 phase for several hundred days., Author(s): Yimu Chen [sup.1] , Yusheng Lei [sup.1] , Yuheng Li [sup.1] , Yugang Yu [sup.2] , Jinze Cai [sup.2] , Ming-Hui Chiu [sup.3] , Rahul Rao [sup.4] , Yue [...]

Due to their weight, the seismic response control of buildings needs a large-scale damper. To reduce the consumption of shape memory alloys (SMAs), this study proposed a dual self-centering pattern accomplished by the coil springs and SMA, which could drive the energy dissipation device to recenter. Combined with the friction energy dissipation device (FD), the dual self-centering friction damper (D-SCFD) was designed, and the motivation and parameters were described. The mechanical properties of D-SCFD, including the simplified D-SCFD mechanical model, theoretical index calculations of recentering, and energy dissipation performance, were then investigated. The seismic response mitigation of the steel frame adopting the D-SCFDs under consecutive strong earthquakes was finally analyzed. The results showed that a decrease in the consumption of SMA by the dual self-centering pattern was feasible, especially in the case of low demand for the recentering performance. Reducing the D-SCFD's recentering performance hardly affected the steel frame's residual inter-story drift ratios when the residual deformation rate was less than 50%, which can help strengthen the controls on the steel frame's peak seismic responses. It is recommended to utilize the D-SCFD with not too high a recentering performance to mitigate the seismic response of the structure. [ABSTRACT FROM AUTHOR]

Peanut southern blight is a soil-borne fungal disease caused by Agroathelia rolfsii (syn. Sclerotium rolfsii) Sacc, which seriously affects peanut yield. The disease mainly affects the stem, pod, and root of the plant, and it is difficult to detect the disease by visual interpretation. Detecting peanut southern blight using existing technology is an urgent problem that needs to be solved. To address this issue, field experiments were conducted in September 2022 to determine whether hyperspectral techniques could be used to assess the severity of peanut southern blight. In this study, we obtained 610 canopy-scale spectral data through field experiments. Firstly, 18 traditional spectral features were calculated. Then, wavelengths of 544 nm, 678 nm, and 769 nm were selected as sensitive by the Relief-F algorithm, and the NDSISB and NSISB were constructed using normalization and ratio calculation methods. Finally, Support Vector Machine (SVM), Light Gradient Boosting Machine (LightGBM), Categorical Boosting (CatBoost), and ANN were used to evaluate the diagnostic ability of all spectral features to assess disease severity levels. The results showed that the NSISB had the highest association with peanut southern blight (R2 = 0.817), exceeding the other spectral features. Compared to the other three models, CatBoost demonstrated superior accuracy, with an overall accuracy (OA) and Kappa coefficient of 84.18% and 78.31%, respectively. The findings of this study can serve as a reference for estimating the severity levels of peanut southern blight using ground-based hyperspectral data. [ABSTRACT FROM AUTHOR]

There are two types of land systems in China: collective-owned and state-owned. Under both systems, differences in land ownership have led to different land-use and management systems, resulting in urban–rural dual structures under the jurisdiction of local governments and urban–rural unitary structures in reclamation areas of the state-owned land system. This has significantly changed the relationship between the rural population and land, which has been intensified by rapid urbanization and industrialization. Therefore, based on the rural population and remote sensing data, this study uses the Tapio decoupling model to determine the relationships between the rural population and residential land under different land systems. The main results indicate that the evolution of the rural population and residential land area under different land systems presents an obvious inverse relationship. From 1995 to 2020, under the jurisdiction of the local government, the land area and population of rural dwellers declined, with the decline in population being faster than that in residential areas. At the same time, the spatial agglomeration of residential areas from the middle to the south of the province expanded. In contrast, the population and residential land area showed significant reverse changes in state-owned domains. Rural residential land area declined, and the rural population increased, most notably in the eastern region. Furthermore, strong negative decoupling between the rural population and rural residential land was observed in areas under local government jurisdiction (accounting for 89.61%), meaning that the population declined while the living area increased, which is not conducive to increasing intensive land-use and productivity. Simultaneously, in state-owned domains, only 33.33% of the rural population and residential land areas presented the above-mentioned negative decoupling, with the remaining 66.67% being coordinated. After 2010, due to the socio-economic gap, the proportion of coordination in local government jurisdiction areas continued to decrease, whereas coordination in reclamation areas remained stable. Therefore, the data suggest that a single land allocation and governance regime across urban and rural domains under the state-owned land system is more helpful in enabling populations and efficient land-use. This suggests that, in the future, it will be helpful to consider promoting the effective integration of urban and rural land markets, optimizing the allocation of urban and rural land resources, and enhancing the reform of the rural land system in order to realize synergistic interactions between the urban and rural populations and construction land in Heilongjiang Province. [ABSTRACT FROM AUTHOR]

In this paper, we investigate deep-learning-based image inpainting techniques for emergency remote sensing mapping. Image inpainting can generate fabricated targets to conceal real-world private structures and ensure informational privacy. However, casual inpainting outputs may seem incongruous within original contexts. In addition, the residuals of original targets may persist in the hiding results. A Residual Attention Target-Hiding (RATH) model has been proposed to address these limitations for remote sensing target hiding. The RATH model introduces the residual attention mechanism to replace gated convolutions, thereby reducing parameters, mitigating gradient issues, and learning the distribution of targets present in the original images. Furthermore, this paper modifies the fusion module in the contextual attention layer to enlarge the fusion patch size. We extend the edge-guided function to preserve the original target information and confound viewers. Ablation studies on an open dataset proved the efficiency of RATH for image inpainting and target hiding. RATH had the highest similarity, with a 90.44 % structural similarity index metric (SSIM), for edge-guided target hiding. The training parameters had 1 M fewer values than gated convolution (Gated Conv). Finally, we present two automated target-hiding techniques that integrate semantic segmentation with direct target hiding or edge-guided synthesis for remote sensing mapping applications. [ABSTRACT FROM AUTHOR]

The climate impact contribution of lakes to sustain the Green Sahara in the mid-Holocene (MH, 6000 years ago) is still under debate. To assess the lake-induced climate response over North Africa, we investigated the roles of western Sahara lakes and Megalake Chad using reconstructions of MH Sahara lake maps as surface boundary conditions for the isotope-enabled atmospheric model MIROC5-iso. Our results show that the western Sahara lakes pushed the West African monsoon northward and extended it eastward by expanding Megalake Chad. This lake–climate impact was caused by the cyclonic circulation response related to the weakened African Easterly Jet and enhanced Tropical Easterly Jet. According to the Budyko aridity index, the northwestern Sahara climate region shifted from hyper-arid to arid or semi-arid with the lake expansion. Moreover, precipitation scarcity could have been reduced by up to 13 % to sustain the semi-humid conditions. Such lake–climate impacts could alleviate Sahara aridity, relying on lake positions in the monsoon regions. Our findings are promising for understanding the contribution of lakes to sustaining the Green Sahara. [ABSTRACT FROM AUTHOR]