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Biochar is widely used to maintain crop yields and the sustainability of agroecosystems due to its characteristics. However, its effect on vegetable yield and quality in southern acidic soils has not been fully elucidated. The effects of two kinds of biochar application rates (3 t ha−1 and 12 t ha−1) on the nutrient availability, nutrient absorption, yield, and fruit quality of sandy acid oxide soil in South China were studied in a 2-year field experiment using two varieties of wax gourd (Tiezhu No. 2 and Dadao). The results showed that optimized fertilization (OPT, nitrogen, phosphorus, and potassium were reduced by 20.0%, 20.6%, and 21.1%, respectively) did not reduce the yield of the different varieties of wax gourd compared to FP (farmer practice). On the basis of the OPT treatment, the application of biochar increased the yield of Tiezhu No. 2 and Dadao wax gourd by 16.0–27.3% and 7.7–13.3%, respectively. The increase in yield was attributed to the improvement in soil organic carbon content which increased by 4.5–19.7%, nutrient effectiveness (NO3−-N and Olsen-P content enhanced by 23.7–27.0% and 15.3–23.4% in Tiezhu No. 2), and nutrient uptake (N, P, K, Ca, and Mg accumulation increased significantly by 21.1%, 46.1%, 36.8%, 25.7%, and 31.9%, respectively) by the plant after the biochar application. Different types of biochar also have some differences in these three aspects. Specifically, under the same dosage, rice biochar has a more significant effect on increasing the yield of winter melon, and has a better effect on the improvement of soil physical and chemical properties, while sawdust biochar has a more significant effect on nutrient absorption. In addition, the commercial quality, namely hardness and glossiness, and the nutritional quality, namely soluble sugar, soluble protein, VC content, and sugar–acid ratio of wax gourd fruits, were significantly improved after the biochar application. In summary, biochar application on acidic soils in South China could achieve a win–win situation in terms of increasing soil nutrient effectiveness to improve vegetable yield and quality while reducing chemical fertilizer.

Background: Type 2 diabetes mellitus (T2DM) is a metabolic syndrome characterized by chronic inflammation, insulin resistance, and islet cell damage. The prevention of T2DM and its associated complications is an urgent public health issue that affects hundreds of millions of people globally. Numerous studies suggest that disturbances in gut metabolites are important driving forces for the pathogenesis of diabetes. However, the functions and mechanisms of action of most commensal bacteria in T2DM remain largely unknown. Methods: The quantification of bile acids (BAs) in fecal samples was performed using ultra-performance liquid chromatography–tandem mass spectrometer (UPLC-MS/MS). The anti-diabetic effects of Bacteroides uniformis (B. uniformis) and its metabolites cholic acid (CA) and chenodeoxycholic acid (CDCA) were assessed in T2DM mice induced by streptozocin (STZ) plus high-fat diet (HFD). Results: We found that the abundance of B. uniformis in the feces and the contents of CA and CDCA were significantly downregulated in T2DM mice. B. uniformis was diminished in diabetic individuals and this bacterium was sufficient to promote the production of BAs. Colonization of B. uniformis and intragastric gavage of CA and CDCA effectively improved the disorder of glucose and lipid metabolism in T2DM mice by inhibiting gluconeogenesis and lipolysis in the liver. CA and CDCA improved hepatic glucose and lipid metabolism by acting on the Takeda G protein-coupled receptor 5 (TGR5)/adenosine monophosphate-activated protein kinase (AMPK) signaling pathway since knockdown of TGR5 minimized the benefit of CA and CDCA. Furthermore, we screened a natural product—vaccarin (VAC)—that exhibited anti-diabetic effects by promoting the growth of B. uniformis in vitro and in vivo. Gut microbiota pre-depletion abolished the favorable effects of VAC in diabetic mice. Conclusions: These data suggest that supplementation of B. uniformis may be a promising avenue to ameliorate T2DM by linking the gut and liver.

Tooth profile errors are the internal excitations that cause gear meshing errors, which are critical error factors affecting gear transmission accuracy. In existing studies, it is usually regarded as a constant or random distribution function. However, the actual machined tooth profile error is not a constant, so this estimation is inconsistent with the actual situation, resulting in an inaccurate evaluation of transmission accuracy. This paper proposes a method for representing tooth profile errors using distribution errors (including systematic and random errors), and a mathematical model of distributed tooth profile errors is presented. The contact stresses of the complex transmission system were compared with those obtained by formulas, proving that tooth profile errors increase contact stress. A method for calculating gear meshing error is proposed to evaluate the actual output accuracy of the complex transmission system. Compared with the test, the output accuracy is reduced by 13.8% under the temperature environment and distributed tooth profile errors. The proposed methods can accurately predict the transmission accuracy of precision transmission systems at the design stage and provide theoretical support for reducing systematic and random errors at the gear machining stage.

China’s small-arched shed-building machinery mostly adopts manual pole casting and mechanical planting, which have low building efficiency and mechanization. Therefore, we designed an automatic feeding device for shed poles to realize automatic single separation, orderly conveyance and timely dropping of poles. Considering shed pole-pitching pass rate as the evaluation index for the regression model, we adopted a three-factor, three-level experimental design and established the speed of the reclaiming ring, height of the falling shed poles and reclaiming ring spacing as the main influencing factors, obtaining 23.94 r/min, 408.799 mm and 1350 mm, respectively in experiments with a trellis qualification rate of 95.36%. Design-Expert 13 was used to perform analysis of variance and determine the optimal parameter combinations. The average measured trellis qualification rate in tests with the bench adjusted and the optimal parameter combination was 94.23%, with 1.13% relative error between test and theoretical optimization values. This confirmed the optimal parameter combination’s dependability. In field verification test results, pick-up card ring speed was 24 r/min; height of trellis pole drop, 410 mm; pick-up card ring spacing, 1350 mm; and pitching rate, 95.37%, obtaining 0.01% error compared with theoretically optimized values. The prototype operational performance was stable and satisfied design requirements.

Ultra High-Performance Concrete (UHPC) is a cement-based composite material with great strength and durability. Fibers can effectively increase the ductility, strength, and fracture energy of UHPC. This work describes the impacts of individual or hybrid doping of basalt fiber (BF) and steel fiber (SF) on the mechanical properties and microstructure of UHPC. We found that under individual doping, the effect of BF on fluidity was stronger than that of SF. Moreover, the compressive, flexural, and splitting tensile strength of UHPC first increased and then decreased with increasing BF dosage. The optimal dosage of BF was 1%. At a low content of fiber, UHPC reinforced by BF demonstrated greater flexural strength than that reinforced by SF. SF significantly improved the toughness of UHPC. However, a high SF dosage did not increase the strength of UHPC and reduced the splitting tensile strength. Secondly, under hybrid doping, BF was partially substituted for SF to improve the mechanical properties of hybrid fiber UHPC. Consequently, when the BF replacement rate increased, the compressive strength of UHPC gradually decreased; on the other hand, there was an initial increase in the fracture energy, splitting tensile strength, and flexural strength. The ideal mixture was 0.5% BF + 1.5% SF. The fluidity of UHPC with 1.5% BF + 0.5% SF became the lowest with a constant total volume of 2%. The microstructure of hydration products in the hybrid fiber UHPC became denser, whereas the interface of the fiber matrix improved.

As a novel design of large-mode-area fiber, the single trench fiber (STF) providing high higher-order-mode suppression with a large mode area for the fundamental mode shows potential for high-power and high-brightness applications. However, the output power of STFs has remained relatively low over the past decade. In this paper, we first conducted a design process for STFs and determined the optimal ratio of the fiber structural parameters. Following this ratio, we fabricated an ytterbium-doped STF and demonstrated an all-fiberized fiber amplifier. The system achieved an output power of 2.5 kW with an M2 factor of 1.396. To the best of our knowledge, the power of the STF in this study is approximately three times higher than the previous single-mode power record.

Landscape elements are crucial to the quality of the built environment. Thermal comfort is one of the important paths through which landscape elements affect the quality of the built environment. Most studies investigate the impacts of the landscape on the outdoor thermal environment, while ignoring the impacts on the indoor environment. A residential area in Chenzhou, a typical city having a hot summer and cold winter climate, was taken as an example to reveal the effect on the indoor thermal environment of landscapes. The annual distribution of the indoor thermal environment was analyzed with the “Envi-met+IDW” model, which was created to evaluate the annual thermal impact. Analytical results show that, from the perspective of the annual cycle, the camphor tree has the best performance in regulating the indoor thermal environment, followed by water and the palm. Manila grass has a very weak impact on indoor thermal comfort throughout the year. Camphor trees, water, and palm extend the “acceptable temperature” by 523 h, 416 h, and 388 h respectively. However, the camphor tree also has the strongest cooling effect on indoor environments during winter, increasing the “heating demand temperature” by 289 h.

Coffee pulp wines were produced through the mixed fermentation of Saccharomyces cerevisiae, and the flavor and sensory characteristics were comparatively evaluated. A total of 87 volatile components were identified from five coffee pulp wines, of which 68 were present in all samples, accounting for over 99% of the total concentration. The sample fermented contained significantly higher levels of volatile metabolites (56.80 mg/g). Alcohols (22 species) and esters (26 species) were the main flavor components, with the contents accounting for 56.45 ± 3.93% and 31.18 ± 4.24%, respectively, of the total. Furthermore, 14 characteristic components were identified as potential odor-active compounds, contributing to sweet and floral apple brandy flavor. Although the characteristic components are similar, the difference in the content makes the overall sensory evaluation of the samples different. The samples formed by fermentation of four strains, which obtained the highest score (86.46 ± 0.36) in sensory evaluation, were further interpreted and demonstrated through the Mantel test. The results of the component analysis were effectively distinguished by OPLS-DA and PCA, and this validation was supported by sensory evaluation. The research results provided a technical reference for the production of coffee pulp wines.

The Moon is the closest celestial body to the Earth. Its rich unique resources are an important supplement to the Earth’s resources and have a profound impact on the sustainable development of human society. As large-scale exploration missions gradually progress, demands for communication, navigation, surveying and other services of lunar-space probes have significantly increased. Constellation navigation and orbit determination technology will become an indispensable part of future lunar exploration infrastructure. This article systematically analyzes the current status of lunar relay navigation satellite networks at home and abroad, summarizes the technical principles of single-satellite and constellation navigation and orbit determination, discusses the technical difficulties in lunar navigation constellation orbit determination and navigation, and analyzes possible solutions. Finally, the development trend of research on high-precision orbit determination and navigation methods for lunar navigation constellations is proposed.

Vertically transmitted endophytes (VTEs) with multi-host-supporting functions are considered plant-acquired heritable traits, which can be manipulated to develop plants with the stable inheritance of these VTEs, defined here as ‘plant endophytic modification (PEM)’. To translate this hypothetical strategy into agricultural and horticultural practice, a PEM was carried out by introducing an anti-fungal pathogenic bacterium, Bacillus cereus (strain ID: ZX-2), into grapevine cuttings and growing the cuttings into vine plants. Bacterial strain XZ-2 is highly efficient in infecting grapevine cuttings and colonizing the interior of the infected cuttings, various parts of the subsequently established vine plants, and next year’s emerging vine shoots and leaves. Profiling the endophytic microbiota by high-throughput sequencing to the grapevines revealed that the colonization with exogenous ZX-2 slightly affected endophytic diversity, while significantly altering the composition and the predicted phenotypes of endophytic microbiota in ZX-2-modified grapevines (ZX-2mg). Most importantly, leaves (from both first- and second-year grapevines) of ZX-2mg conferred significantly higher (p < 0.001) anti-fungal pathogen abilities and a reduction in naturally occurring lesion area than leaves compared to the control grapevines. For all detected vines, a significant correlation (N = 37, r = 0.418; p < 0.01) between fungal pathogen inhibition rates and B. cereus (ZX-2) isolation rates was observed. In addition, ZX-2mg showed some growth promotion and a delay (15–20 days) in leaf abscission. The work established an alternative strategy to create plant lines with functions of specific VTEs via PEM, confirming the practical value of PEM in future organic farming systems.

The grain size effect is an important factor in determining the material removal behavior of polycrystalline silicon (p-Si). In the present study, to improve the understanding of nanoscale machining of p-Si, we performed molecular dynamics simulation of nanometric cutting on a p-Si workpiece and discussed the grain size effect on material removal behavior and subsurface damage formation. The simulation results indicate that when cutting on the polycrystal workpiece, the material removal process becomes unstable compared with single crystals. Higher removal efficiency, less elastic recovery and higher frictional coefficient are observed as the average grain size decreases. In the subsurface workpiece, when the grain size decreases, slip along grain boundaries merges as a nonnegligible process of the plastic deformation and suppresses the elastic deformation ahead of the cutting tool. It is also revealed that when cutting on a polycrystal workpiece with smaller grains, the average stress decreases while the workpiece temperature increases due to the impediment of heat transfer by grain boundaries. These results could provide a fundamental understanding in the material deformation mechanism of p-Si during nanoscale machining.

Long-term exposure to lead (Pb) can result in chronic damage to the body through accumulation in the central nervous system (CNS) leading to neurodegenerative diseases, such as Alzheimer’s disease (AD). This study delves into the intricate role of miR-671/CDR1as regulation in the etiology of AD-like lesions triggered by chronic Pb exposure in adult mice. To emulate the chronic effects of Pb, we established a rodent model spanning 10 months of controlled Pb administration, dividing 52 C57BL/6J mice into groups receiving varying concentrations of Pb (1, 2, or 4 g/L) alongside an unexposed control. Blood Pb levels were monitored using serum samples to ensure accurate dosing and to correlate with observed toxicological outcomes. Utilizing the Morris water maze, a robust behavioral assay for assessing cognitive functions, we documented a dose-dependent decline in learning and memory capabilities among the Pb-exposed mice. Histopathological examination of the hippocampal tissue revealed tell-tale signs of AD-like neurodegeneration, characterized by the accumulation of amyloid plaques and neurofibrillary tangles. At the molecular level, a significant upregulation of AD-associated genes, namely amyloid precursor protein (APP), β-secretase 1 (BACE1), and tau, was observed in the hippocampal tissue of Pb-exposed mice. This was accompanied by a corresponding surge in the protein levels of APP, BACE1, amyloid-β (Aβ), and phosphorylated tau (p-tau), further implicating Pb in the dysregulation of these key AD markers. The expression of CDR1as, a long non-coding RNA implicated in AD pathogenesis, was found to be suppressed in Pb-exposed mice. This observation suggests a potential mechanistic link between Pb-induced neurotoxicity and the dysregulation of the CDR1as/miR-671 axis, which warrants further investigation. Moreover, our study identified a dose-dependent alteration in the intracellular and extracellular levels of the transcription factor nuclear factor-kappa B (NF-κB). This finding implicates Pb in the modulation of NF-κB signaling, a pathway that plays a pivotal role in neuroinflammation and neurodegeneration. In conclusion, our findings underscored the deleterious effects of Pb exposure on the CNS, leading to the development of AD-like pathology. The observed modulation of NF-κB signaling and miR-671/CDR1as regulation provides a plausible mechanistic framework for understanding the neurotoxic effects of Pb and its potential contribution to AD pathogenesis.