Search Results (2,224)

The long-term stability of rock–concrete composites largely depends on the mechanical properties and durability of the rock–concrete interface. This study investigated the coupling effect of interfacial roughness and acid sulfate corrosion on sandstone–concrete composites by using uniaxial compression tests combined with acoustic emission (AE) monitoring. The results showed that corrosion continuously reduces the mechanical properties of the specimens with peak strength and elastic modulus, exhibiting a two-stage evolution: rapid degradation in the early stage followed by a slow decline in the later stage. After 60 days of corrosion, the peak strength for composites with JRC = 5, JRC = 10, and JRC = 15 interfaces decreased by 46.59%, 44.34%, and 50.43%, respectively. The elastic modulus exhibited the same pattern of variation, and the decreasing rate was 68.90%, 66.96%, and 76.46% for the JRC = 5, JRC = 10, and JRC = 15 groups. Acoustic emission activities appeared earlier and were more significant after corrosion. With the effect of corrosion, the fracture mode evolved from tensile-dominated cracks to mixed tensile–shear cracks with a stronger shear component. Fractal analysis of AE energy revealed that the Hurst exponent decreased from 0.842–0.864 in the natural state to 0.503–0.567 after 60 days of immersion, whereas the fractal dimension increased from 1.136–1.182 to 1.433–1.497, indicating a decrease in the persistence and increase in complexity of the acoustic emission energy release process. Overall, the moderately rough interface (JRC = 10) achieved a better balance between initial strengthening and long-term corrosion resistance. These findings provide experimental support for evaluating the durability of sandstone–concrete composites in acidic sulfate environments. Full article

Bamboo plantations are increasingly recognized as significant terrestrial carbon sinks, yet accurate estimation of biomass and carbon stocks requires species-specific, regionally validated allometric models. Bambusa emeiensis L.C.Chia & H.L.Fung (ci bamboo) is among the most ecologically and economically important clump-forming bamboo species in southwestern China, but robust multi-regional allometric models are lacking. Using destructive sampling data from 127 culms across two major production areas—Sichuan Province (n = 82) and Guizhou Province (n = 45)—we developed additive biomass and carbon storage model systems enforcing mathematical additivity via nonlinear seemingly unrelated regression (NSUR). Allometric equations used diameter at breast height (D), culm height (H), and compound variables (DH, D²H) as predictors. Regional models achieved R_a² of 0.0879–0.8320 total relative error (TRE): −0.99% to 0.04% for biomass and R_a² of 0.0923–0.8282 (TRE: −1.01% to 0.03%) for carbon storage; culm and total aboveground models attained R_a² ≥ 0.52. Organ-level carbon content (40.79%–44.46%) was significantly lower than the intergovernmental panel on climate change (IPCC) default of 50% (one-sample t-test, p < 0.01 for all organs), with Sichuan values exceeding Guizhou values (independent-samples t-test, p < 0.01), indicating that use of the default would overestimate carbon stocks by 12%–22%. Cross-regional validation revealed prediction biases of up to ±19.24% when applying single-region models outside their training area, whereas the combined model held errors within ±11.36% for biomass and ±8.49% for carbon storage. External validation using 32 independent culms from Hunan, Yunnan, and Chongqing confirmed the robustness of the combined model (TRE: −6.30% to 4.27%). A key limitation is that belowground biomass was not measured. The established models provide scientifically rigorous and practically applicable tools for regional carbon accounting of B. emeiensis plantations under China’s national greenhouse gas inventory framework and for informing sustainable bamboo management planning, and demonstrate that species- and region-specific carbon fractions are essential for accurate carbon stock assessments. Full article

The rice leaf roller (RLR), Cnaphalocrocis medinalis (Guenée), is a major migratory pest that threatens rice production across East Asia. Effective management of migratory pests relies fundamentally on accurately identifying their source areas, population dynamics, and key environmental drivers. Western Hunan is a critical rice-growing region characterized by unique topography and varied climates, making it a principal pathway for RLR migration. Based on 14-year (2011–2024) monitoring datasets, we identified substantial interannual variability in July RLR abundance in Western Hunan, when the population typically peaks, highlighting the episodic and unstable nature of regional infestations. Back-trajectory simulations reveal that heavy occurrence years of RLR feature clear northward migration pathways from the Indo-China Peninsula and South China to Western Hunan in July, supported by strong southerly winds along the route. Multiple linear regression analysis further shows that spring warmth initially facilitates high population accumulation in source regions, and the synergistic effect of source-region precipitation deficits and abundant local rainfall triggers large-scale immigration into Western Hunan. These meteorological factors collectively account for up to 66% of the interannual variability in RLR population fluctuations, confirming that climatic conditions largely determine outbreak severity. This provides a robust quantitative framework for regional early-warning systems and sustainable pest management in migratory corridors. Full article

Background/Objectives: As a traditional Chinese medicinal herb, Cnidii Fructus is widely used in clinical practice. Its volatile organic compounds (VOCs) are closely related to its antipruritic effect and insecticidal properties. Due to the susceptibility of this medicinal herb to mold contamination, adopting appropriate sterilization measures is of great significance for its storage. ⁶⁰Co irradiation is widely used for this purpose due to its various advantages. Methods: This study employed Gas Chromatography–Ion Mobility Spectrometry (GC-IMS) combined with multivariate statistical analysis to systematically investigate the influence of different ⁶⁰Co irradiation doses (0, 3, 6, 9 kGy) on the VOCs of Cnidii Fructus and associated metabolic regulatory mechanisms. Results: A total of 115 VOCs were tentatively identified. Statistical analysis revealed dose-dependent effects: 3 kGy irradiation caused the least compositional perturbation, best preserving original chemical characteristics; 6 kGy induced more pronounced compositional changes; and 9 kGy triggered substantial chemical composition reconstruction. Differential metabolite enrichment analysis indicated that medium and high doses of irradiation primarily perturbed central carbon metabolic pathways, including pyruvate metabolism, glycolysis/gluconeogenesis, and glyoxylate and dicarboxylate metabolism. Key differential components were tentatively identified (e.g., α-Thujone, α-Pinene, β-Pinene) that possess pharmacological activities closely associated with the traditional efficacy of Cnidii Fructus. Conclusions: When the irradiation dose is 3 kGy, the VOCs profile of Cnidii Fructus is most similar to that of the non-irradiated control group, suggesting that its compositional profile may be closer to that of traditional high-quality medicinal materials. Meanwhile, the differential metabolites and core metabolic pathways identified in this study can provide a chemical reference for the quality control of irradiated Cnidii Fructus. The findings provide a theoretical basis and technical support for the rational application of ⁶⁰Co irradiation sterilization in the processing of Chinese medicinal materials and their powders. Full article

Det Norske Misjonsselskap (Norwegian Missionary Society, NMS) was founded in Stavanger, Norway, in 1842. Having established its first mission field in Africa, it then made plans to work in Asia. In 1902, the first missionaries were sent out to Hunan, an inland, culturally isolated, and conservative Chinese province that experienced particularly strong anti-foreigner and anti-Christian waves. This article argues that the NMS developed a distinctive, pragmatic strategy of political accommodation—rooted in its Pietistic Lutheran social ethos and a Norwegian pioneering spirit—to ensure its institutional survival in Hunan. Examining the NMS’s responses to two major political turning points, the Anti-Christian Movement (1924–1927) and the New Life Movement (1934–1937), the article reveals three key findings: First, the NMS’s proclaimed “neutrality” was not merely a passive stance but an active survival tactic, evolving from a claim grounded in Norway’s geopolitical neutrality into a strategic rhetoric for navigating local political risks. Second, the missionaries’ “excessive expectations” of the Nationalist government, particularly during the New Life Movement, stemmed from a structural cognitive bias shaped by their deep institutional embedding in the KMT-governed local order. Third, their ultimate withdrawal was less a simple political misjudgement than the logical endpoint of a survival model that lacked a contingency plan for revolutionary change. By tracing this specific case, the article contributes to the historiography of Christianity in modern China by illuminating the diversity of missionary strategies beyond the dominant Anglo-American coastal narratives. Full article

Red mud, as a by-product of alkaline regeneration of alumina, has limited application due to its strong alkalinity, fine particle size, and complex composition. In this work, red mud porous ceramics with uniform pore size distribution and high mechanical strength were prepared using a foam-gel casting method. The effects of solid loading and sintering temperature on the microstructure of porous ceramics were systematically investigated. The porosity of red mud-based porousceramics sintered at 1150 °C with a solid content of 60.4% was 33.7%, and the maximum compressive strength was 54.70 MPa, while the porousceramics prepared with a solid loading of 34.1% and sintered at 1050 °C achieved a maximum porosity of 79.7% and a compressive strength of 2.36 MPa. Increasing the solid loading reduced porosity and enhanced compressive strength, allowing for the tailoring of mechanical properties to meet specific application requirements. Higher sintering temperature promoted the formation of the liquid phase, enhanced particle bonding, and further improved the compressive strength. Additionally, toxicity leaching tests confirmed that the ceramics are environmentally safe, with leachate levels well within regulated limits. These results demonstrate the potential of foam-gel casting as an effective route for transforming red mud into value-added porous ceramics, thereby contributing to sustainable waste utilization and broadening the application prospects of red mud-based materials. Full article

The efficient separation of tungsten and molybdenum represents a pivotal challenge for the effective, high-value-added utilization and recycling of these strategic metal resources. Developing clean and recyclable separation processes has become a major focus of research, reflecting a growing emphasis on sustainability. This study proposes a method for the efficient and deep separation of molybdenum and tungsten from tungstate-based mixed oxides by leveraging their differential coordination properties with hydrogen peroxide. The composites prepared by mechanical mixing were characterized using techniques such as ICP, SEM, XRD, and Raman spectroscopy. The results demonstrated a significant difference in the dissolution behavior of MoO₃ and WO₃ in hydrogen peroxide, indicating a substantial coordination disparity between MoO₃ and WO₃ toward H₂O₂, which can be effectively exploited for Mo/W separation. Additionally, hydrothermal synthesis was employed to simulate the separation under more realistic conditions. In this study, hydrogen peroxide was selected as an effective reagent for separation, and the influence of multiple variables was systematically evaluated. The results demonstrated that under optimal conditions—specifically at a molar ratio nMo/nW = 40, a temperature of 65 °C, nH₂O₂/nM = 1.25 and a reaction time of 1.5 h—a maximum separation factor of 124 between tungsten and molybdenum was achieved. This process exhibits significant potential for industrial application due to its low consumption of H₂O₂, large separation factor, and cost-effectiveness. Full article

Ultra-high performance geopolymer concrete (UHPGC) has emerged as a low-carbon cementitious material with high mechanical performance and thus offers potential as a substitute for Portland cement-based ultra-high-performance concrete (UHPC). Experimental evidence on the eccentric compression response of reinforced UHPGC (R-UHPGC) columns, however, remains limited. In this study, six reinforced columns were tested under eccentric compression, with concrete type and eccentricity ratio taken as the main variables. The structural response was examined in terms of failure pattern, peak resistance, axial load–deflection behavior, and ductility. The results showed that at the same eccentricity ratio, the peak resistance of the R-UHPGC columns was approximately 20% lower than that of the corresponding R-UHPC columns. As eccentricity increased, the axial load resistance decreased, whereas the mid-height deflection and ductility increased. On the basis of the test results, available prediction methods for moment magnification factor and ultimate resistance originally developed for R-UHPC columns were assessed for their suitability for R-UHPGC members. A preliminary analytical approach was then established for estimating the second-order effect and load-carrying capacity of R-UHPGC columns. Full article

It is widely accepted in prokaryotic systematics that a 95–96% ANI (average nucleotide identity) value is equivalent to 70% dDDH (digital DNA–DNA hybridization) value in prokaryotic systematics. However, we recently found that a 70% dDDH value was equivalent to an approximately 96.7% ANIm value in the genus Micromonospora based on a correlation analysis between dDDH and ANIm from a total of 1770 pairs of type Micromonospora strains (60 type strains). Therefore, we proposed that 96.7% ANIm (ANI based on the MUMmer algorithm) value could act as the threshold value in delineating Micromonospora species. Meanwhile, the taxonomic status of an actinobacterial strain HUAS LYJ1^T, isolated from the rhizosphere soil of Camellia oleifera, was determined by using a polyphasic method. A 16S rRNA gene sequence analysis indicated that strain HUAS LYJ1^T shared the highest similarity to Micromonospora wenchangensis CCTCC AA 2012002^T (99.3%). Phylogenetic trees based on 16S rRNA gene and whole-genome sequences demonstrated that strain HUAS LYJ1^T was most closely related to M. wenchangensis CCTCC AA 2012002^T. However, the ANIm value between them was 95.77%, below the 96.7% cut-off point recommended above; the dDDH value between them was 63.2%, also far below the 70% threshold value in delineating bacterial species. Based on these molecular data, as well as phenotypic and chemotaxonomical features, it is concluded that strain HUAS LYJ1^T represents a novel Micromonospora species, for which the name Micromonospora cynarisoli sp. nov. is proposed. In addition, it was found that the ANIm and dDDH values of Micromonospora haikouensis DSM 45626^T, Micromonospora harpali NEAU-JC6^T and Micromonospora oryzae DSM 102119^T were 97.21–97.86% and dDDH 73.9–79.6%, respectively, above the 96.6% ANIm and 70% dDDH threshold value in delineating Micromonospora species. Consequently, according to rule 42 of the International Committee on Systematics of Prokaryote Code, we propose that M. harpali Fang et al. 2015 and M. oryzae Kittiwongwattana et al. 2015 are later heterotypic synonyms of M. haikouensis Xie et al. 2012. Full article

Investigating the effects of sublethal pesticide doses on pest population succession and physiological metabolism is crucial for IPM and resistance delaying. This study evaluated sublethal effects of abamectin on Diaphorina citri using two-sex life tables, population modeling, and measurements of hormone levels, energy reserves, and gene expression to reveal its transgenerational impacts. Results showed dose-dependent and transgenerational effects: both F₀ and F₁ generations experienced prolonged development and reduced longevity under LC₂₅/LC₅₀ stress. Life-table parameters (r, λ, R₀, GRR, T) declined, and the model predicted a sharp population decrease after 60 days (from 10,357 to 1711 and 372 individuals under LC₂₅ and LC₅₀, respectively). The findings indicated that abamectin suppresses population growth by delaying development and limiting adult recruitment. Following abamectin treatment, hormone levels (20E and JH) showed dynamic fluctuations with delayed peaks in the treated groups, while energy reserves (glycogen and triglycerides) were generally reduced. Vitellogenin gene expression was mostly suppressed, except for a transient increase in Vg-1 and Vg-A1 (LC₂₅, day 9), whereas VgR was generally up-regulated except in the LC₂₅ group. Both LC₂₅ and LC₅₀ treatments suppressed D. citri development and reproduction by disrupting hormone balance and energy metabolism, without inducing hormesis. These findings provide a theoretical basis for optimizing field application strategies and support the use of abamectin in IPM programs to reduce outbreak risk and delay resistance development. Full article

Conventional powdered biochar encounters severe bottlenecks in practical water treatment, such as difficult separation, easy loss, and potential secondary pollution. This work aimed to develop recyclable and high-performance adsorbents by preparing iron-doped biochar/sodium alginate composite microspheres (BC/MBC500-ALF) through Fe³⁺ cross-linking. Using corn stalk biochar and KMnO₄-modified biochar as adsorbent components and sodium alginate (SA) as a green shaping matrix, SA formed a stable egg-box hydrogel network to convert powdered biochar into uniform microspheres. Batch adsorption experiments revealed that the optimal pH for oxytetracycline (OTC) adsorption was 9, with adsorption capacities of 136.28 mg/g for BC500-ALF and 182.91 mg/g for MBC500-ALF. Kinetic analysis showed that BC500-ALF followed pseudo-first-order kinetics (R² = 0.983) dominated by physisorption, while MBC500-ALF fitted pseudo-second-order kinetics (R² = 0.994) dominated by chemisorption. The maximum Langmuir adsorption capacities at 308 K were 220.75 mg/g and 495.05 mg/g, respectively. Thermodynamic parameters confirmed a spontaneous and endothermic process. The adsorption mechanisms involved hydrogen bonding, π–π stacking, electrostatic attraction, metal-bridging complexation, and Fe–Mn oxide-mediated redox reactions. SA exerted dual functions in structure stabilization and adsorption enhancement. This composite provides an efficient and eco-friendly approach for tetracycline antibiotic pollution control in aqueous environments. Full article

This study has investigated the occurrence characteristics and population damage of weeds in double-cropping direct-seeded rice fields in Hunan, and has identified efficient and safe pre- and post-emergence herbicides to enhance resistance management. Field trials were conducted at two representative sites (Yiyang and Changsha) in Hunan in 2024~2025. Weed community composition and emergence patterns were systematically monitored. The inhibitory effects of weed infestations on rice growth and yield were quantified. The biological activity and field efficacy of various herbicide classes against barnyardgrass (Echinochloa crus-galli) were evaluated via greenhouse bioassays and field trials. Weed emergence lasted 3–48 days after sowing (DAS) with three distinct peaks. Grasses emerged earliest and dominated the community, with barnyardgrass peaking at 13–17 DAS (≈50% of total weeds), followed by broadleaves at 20 DAS (≈40%) and sedges at 25 DAS (<20%). Weed infestation drastically suppressed rice height (max 19% reduction) and tillering (max 50% reduction), with mixed-weed and grass-dominated plots causing the severest yield losses (92.0% and 90.5%, respectively), versus only 18.0% in broadleaf-dominated plots. Greenhouse bioassays showed that oxaziclomefone had the highest intrinsic activity against barnyardgrass (GR₉₀ = 17.70 g ai ha⁻¹). In pre-emergence applications in field trials, pretilachlor (900 g ai ha⁻¹) and mefenacet (147.6 g ai ha⁻¹) provided >96.8% control at 20 and 40 days after treatment (DAT), while oxaziclomefone (66 g ai ha⁻¹) achieved 88.2% control at 20 DAT. For post-emergence herbicides, Profoxydim showed the highest intrinsic activity (GR₉₀ = 33.01 g ai ha⁻¹), followed by feproxydim (GR₉₀ = 33.45 g ai ha⁻¹) and flusulfinam (GR₉₀ = 64.55 g ai ha⁻¹). In field trials, flusulfinam provided 100% control with superior crop safety at 20 and 40 DAT, while Florpyrauxifen-benzyl, feproxydim, and metamifop reached >93% efficacy. In conclusion, weed emergence in Hunan direct-seeded rice follows a three-peak pattern, with barnyardgrass being the most destructive species. An integrated strategy combining pretilachlor (pre-emergence) and flusulfinam (post-emergence), rotated with florpyrauxifen-benzyl and feproxydim, is recommended for effective barnyardgrass management and resistance mitigation. Full article

A comprehensive annotated checklist of the members of the phytophagous ladybird beetle tribe Epilachnini (Coccinellinae) in China is compiled based on existing published sources and incorporates the latest taxonomic and nomenclatural updates. The checklist documents 176 extant species across 10 genera and provides analyses of regional species richness, distribution, and host plant associations. Regarding regional species richness, Yunnan Province is home to the highest number of species (76), followed by Taiwan (50), Sichuan (48), Guizhou (48), Guangxi (43), Tibet (43), Guangdong (25), Hainan (17), Hubei (17), Hunan (13), Shaanxi (13), Fujian (12), Henan (10), Jiangsu (10), Anhui (7), Shandong (7), Zhejiang (7), Jiangxi (5), Hong Kong (5), Gansu (5), Beijing (4), Hebei (4), Liaoning (3), Shanxi (2), and Chongqing, Jilin, Heilongjiang, Ningxia, and Xinjiang (each with one species). Among the recognized genera, Epilachna Chevrolat, 1837, is currently the most species-rich genera, with 59 species, followed by Afissa Dieke, 1947 (34), Uniparodentata Wang & Cao, 1993 (28), Henosepilachna Li, 1961 (29), Afidentula Kapur, 1958 (10), Diekeana Tomaszewska & Szawaryn, 2015 (9), and Epiverta Dieke, 1947 (4). Additionally, Afidenta Dieke, 1947, Cynegetis Chevrolat, 1837, and Subcoccinella Agassiz & Erichson, 1845 are each represented by a single species. Host plant data are currently available for only 72 species (approximately 41% of the species recorded in China), which are associated with 177 plant species across 34 families. The most frequently recorded host plant families are Solanaceae (43 species), Cucurbitaceae (32), Urticaceae (15), Fabaceae (14), Asteraceae (14), and Poaceae (10), whereas each of the remaining 28 families comprises fewer than 10 host species. For 104 species (59% of the Chinese members of the tribe), host plant associations remain unknown, highlighting a substantial gap in our understanding of their feeding habits. Full article

Investigating soil seepage considering free surface conditions under complex geological conditions is of great significance to ensure the safety of dams. In recent years, physics-informed deep learning (PINN) has become a cross-disciplinary hotspot for solving forward and inverse problems based on partial differential equations. However, the challenges in free surface simulation have confined the majority of current PINN research to seepage problems under fixed boundary conditions. To address the above issues, we propose a physics-informed deep learning-based approach for steady seepage in dams. In the proposed method, two different free surface approximation strategies are introduced to accommodate varying boundary conditions in the dam seepage problem. The first strategy approximates the free boundary by sampling points, while the second strategy approximates the free boundaries by an additional deep neural network. To validate the proposed methods, three benchmark cases with different boundary conditions have been conducted. The results indicate that the proposed approach effectively simulates steady seepage in dams. Both point-sampling and deep neural network-based free surface approximation strategies demonstrate high accuracy in predicting the location of the phreatic surface and the discharge of the seepage. Specifically, the prediction results are comparable in accuracy to analytical solutions and advanced numerical simulation methods. Full article

Background/Objectives: Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by progressive cognitive decline and chronic neuroinflammation. Increasing evidence suggests that the imbalance between pro-inflammatory Th17 cells and anti-inflammatory regulatory T (Treg) cells plays a critical role in AD pathogenesis. However, a comprehensive synthesis of how natural compounds modulate Th17/Treg balance in AD remains lacking. This review aims to summarize current preclinical evidence on Th17/Treg dysregulation and evaluate the immunomodulatory potential of natural compounds in AD. Methods: This review focuses on preclinical evidence derived from experimental AD models and related inflammatory models to evaluate how natural compounds modulate Th17/Treg balance, neuroinflammation, and cognitive function, with an emphasis on underlying molecular and immunometabolic mechanisms. Results: Th17/Treg imbalance contributes significantly to AD-associated neuroinflammation and disease progression. Representative natural compounds, including paeoniflorin, quercetin, and ganoderic acid A, have demonstrated the ability to rebalance Th17/Treg responses, suppress neuroinflammation, and improve neuronal survival in experimental models. These compounds are highlighted due to their relatively stronger evidence in AD-related models and more clearly defined immunomodulatory mechanisms. These effects are partially mediated through modulation of key signaling pathways and immunometabolic reprogramming. Conclusions: Targeting Th17/Treg balance with natural compounds represents a promising multi-target immunomodulatory strategy for AD. However, most current evidence is derived from preclinical or non-AD models, and clinical validation remains limited. Future studies should prioritize AD-specific models and translational research to evaluate therapeutic potential in humans. Full article