Search Results (642)

This study addresses the need for effective bamboo monitoring in smart forestry as UAV imagery and AI-based methods continue to advance. Bambusa stenostachya (thorny bamboo), commonly found in the badland regions of southern Taiwan, spreads rapidly due to its strong reproductive capacity and extensive rhizome system, often causing forestland degradation and challenges to sustainable management. An automated detection approach is therefore required to capture bamboo dynamics and support forest resource assessment. We use a dual-component framework for detecting bamboo forests and individual bamboo clumps from high-resolution UAV orthomosaic imagery. The first component performs semantic segmentation using U-Net or SegFormer to extract bamboo forest areas and generate a corresponding forest mask. The second component independently applies instance segmentation using YOLOv8-Seg and Mask R-CNN to delineate and localize individual bamboo clumps. The dataset was collected from Compartment 43 of the Qishan Working Circle in Kaohsiung, Taiwan. Experimental results show strong model performance: bamboo forest segmentation achieved an F1-score of 0.9569, while bamboo clump instance segmentation reached a precision of 0.8232. These findings demonstrate the promising potential of deep learning-based segmentation techniques for improving bamboo detection and supporting operational forest monitoring. Full article

Photovoltaic (PV) systems are vital to contemporary renewable energy generation systems. However, complex operating conditions, such as variable loads, grid uncertainty, and unstable sunlight, pose a serious threat to the stability of the power system integrated with PV generation. To maintain stable operation under such conditions, PV systems must dynamically regulate their power output through a boost converter, thereby preventing excessive DC bus voltage and power levels. This article first summarizes practical control requirements for PV systems under complex operating conditions and subsequently proposes a multi-objective control method for boost converters in PV applications to enhance system adaptability. The proposed strategy enables seamless transitions between operating modes, including DC-link voltage control, current control, power control, and maximum power point tracking (MPPT). The dynamic behavior of the control method during mode switching is theoretically analyzed. Simulation results verify the correctness of the analysis and demonstrate the effectiveness of the proposed method under challenging PV operating conditions. Full article

An innovative dispersive liquid–liquid microextraction technique utilizing a solid dispersion was established for the quantification of triazine herbicides in environmental water samples. Naturally derived monoterpenoids were utilized as eco-friendly extraction solvents, markedly decreasing the reliance on harmful extraction solvents. A small amount of Pop Rocks candy served as a solid dispersant; the rapid release of carbon dioxide promoted the generation of fine monoterpenoid droplets, effectively replacing conventional hazardous liquid dispersants. The solidification technique of floating organic droplets facilitated the effective phase separation of monoterpenoids from aqueous samples, thereby obviating the need for centrifugation. Triazine herbicides exhibited good linearity within the concentration range of 0.008–0.8 mg/L with correlation coefficients above 0.99 and detection limits of 0.002 mg/L. The proposed method was effectively implemented on surface and groundwater samples, attaining recoveries between 86.4% and 98.0%. Molecular docking analysis suggests a spontaneous binding between the monoterpenoid and triazine herbicides. A comprehensive green assessment utilizing two evaluation tools confirmed the excellent environmental performance of the method. This technique offers superior greenness and simplicity compared with conventional techniques, demonstrating strong potential for application in the environmental analysis of pesticide residues. Full article

Shanxi Province, located in northern China, characterized by a warm-temperate monsoon climate, complex mountainous topography, and vegetation dominated by trees of Fagaceae and Pinaceae, provides diverse habitats for Russula diversity. Recent investigations on macrofungi in this region revealed nine new Russula species based on integrated morphological and multi-locus phylogenetic analyses (ITS, nrLSU, rpb2, tef1), which are described and illustrated in this paper. These new taxa are classified into three subgenera of Russula: one species of subgen. Brevipes, four of subgen. Heterophyllidia, four of subgen. Russula. This work enhances the understanding of Russula resources in China’s temperate zone. Full article

During layered mining of extra-thick coal seams in deep rock-burst-prone mines, a thick bottom coal layer facilitates the accumulation of elastic strain energy in the floor strata. This stored energy may be released under mining-induced disturbances during retreat, thereby triggering rock-burst events. To mitigate floor energy accumulation at the lower-slice working face of extra-thick coal seams, previous studies have primarily adopted floor blasting for pressure relief. However, conventional blasting is often associated with poor energy utilization and limited controllability of the pressure-relief range, which hampers achieving the intended relief performance. Accordingly, this study proposes a shaped charge blasting scheme to reduce floor energy accumulation. ANSYS/LS-DYNA simulations and UDEC-based energy analyses, together with theoretical analysis and field validation, were conducted to clarify the mechanism of directional fracture propagation and the evolution of floor elastic energy before and after blasting. The results showed that the synergistic effects of the high-velocity jet and quasi-static pressure in shaped charge blasting generated a through-going fracture aligned with the maximum horizontal principal stress. This fracture effectively segmented the high-stress region in the floor and increased the maximum fracture length along the shaped charge direction to 10–13 times that achieved by conventional blasting. UDEC simulations and theoretical analysis indicated that the peak elastic energy in the floor was reduced by up to 54.08% after shaped charge blasting. Field measurements further showed that shaped charge blasting limited the maximum roadway floor heave to 300 mm and reduced floor deformation by 35–42% compared with the case without pressure relief. Overall, shaped charge blasting effectively blocks stress-transfer pathways and improves energy dissipation efficiency, providing theoretical support and a practical technical paradigm for safe and efficient mining of deep extra-thick coal seams. Full article

Acetate esters, synthesized by alcohol acyltransferase (AATases) encoded primarily by the ATF1 gene, are pivotal for the desirable fruity aroma in fermented foods. However, the role and regulatory impact of ATF1 in solid-state fermented meat remain largely unexplored. This study engineered Saccharomyces cerevisiae by knocking out and overexpressing ATF1 to investigate its influence on flavor formation in a sour meat model system. Compared to the wild-type strain, ATF1 overexpression (SCpA group) increased ethyl acetate content by 70.15% and uniquely produced significant levels of isoamyl acetate. Conversely, ATF1 deletion (SCdA group) led to a 61.23% reduction in ethyl acetate. Transcriptomic analysis revealed that ATF1 overexpression triggered a systemic metabolic shift, not only activating the final esterification step but also upregulating key genes in central carbon metabolism (SUC2, ICL1), amino acid biosynthesis, and precursor supply pathways (ACS2, ADH1). This synergistic regulation redirected metabolic flux towards the accumulation of both alcohol and acyl-CoA precursors, thereby amplifying acetate ester synthesis. Our findings demonstrate that ATF1 is a critical engineering target for flavor enhancement in fermented meats and uncover a broader metabolic network it influences, providing a robust strategy for the targeted modulation of food flavor profiles. Full article

Background: The Remnant Cholesterol Inflammatory index (RCII) has been proposed as a marker of insulin resistance and systemic inflammation. However, its associations with incident stroke, incident heart disease, and all-cause mortality among individuals with cardiovascular–kidney–metabolic (CKM) syndrome stages 0–3 remain uncertain. Methods: This longitudinal cohort study used data from the China Health and Retirement Longitudinal Study (CHARLS). The remnant cholesterol inflammatory index (RCII) was calculated as [RC (mg/dL) × hs-CRP (mg/L)]/10. Outcomes included incident stroke, incident heart disease, and all-cause mortality. Covariates were prespecified based on established risk factors. Cox proportional hazards models and restricted cubic spline (RCS) analyses were used to evaluate associations between RCII and each outcome. Long-term RCII patterns were identified using k-means clustering. Robustness was assessed using subgroup and sensitivity analyses. Results: The final study involved 6994 participants in the stroke and heart disease cohort and 7245 participants in the all-cause mortality cohort, all within CKM syndrome stages 0–3. Higher baseline RCII was associated with increased risks of stroke (HR = 1.55, 95% CI: 1.14–2.12) and all-cause mortality (HR = 1.67, 95% CI: 1.37–2.04) compared with the lowest quantile. Cumulative RCII showed a stronger association with all-cause mortality (HR for Q3 = 2.18, 95% CI: 1.54–3.11). RCS analysis suggested a J-shaped, non-linear association between cumulative RCII and all-cause mortality. (p for non-linearity < 0.05). K-means clustering further indicated that, relative to the reference group, cluster 2 (high-to-higher) had the highest risk of incident heart disease, whereas cluster 3 (high-to-moderate) had the highest risk of all-cause mortality. Conclusions: Higher RCII levels were associated with higher risks of stroke, heart disease, and all-cause mortality among individuals with CKM stages 0–3. RCII may serve as a promising biomarker for early risk stratification in clinic and prevention efforts in this population. Full article

The combined effects of climate change and socio-economic development have intensified the risk of water supply–demand imbalance in China. To project future trends, this study develops a multi-scenario coupled prediction framework integrating climate, socio-economic, and human activity drivers, combining data-driven and physically based modeling approaches to assess terrestrial water storage imbalance in nine major river basins under six representative SSP–RCP scenarios through the end of the 21st century. Using ISIMIP multi-model runoff outputs along with GDP and population projections, agricultural, industrial, and domestic water demands were estimated. A Water Conflict Index was proposed by integrating the Water Supply–Demand Stress Index and the Standardized Hydrological Runoff Index to identify high-risk basins. Results show that under high-emission scenarios, the WCI in the Yellow River, Hai River, and Northwest Rivers remains high, peaking during 2040–2069, while low-emission scenarios significantly alleviate stress in most basins. Water allocation inequity is mainly driven by insufficient supply in arid northern regions and limited redistribution capacity in resource-rich southern basins. Targeted strategies are recommended for different risk types, including inter-basin water transfer, optimization of water use structure and pricing policies, and the development of resilient management systems, providing scenario-based quantitative support for future water security and policy-making in China. Full article

Converting agricultural solid waste into porous biochar for HCHO adsorption is considered as a “two birds with one stone” strategy, which can achieve the environmental goal of “treating waste with waste”. Unfortunately, the HCHO adsorption performance of pristine biochar is generally unsatisfactory, which is derived from its poor surface activity and insufficient number of pores. In this study, a series of nitrogen-doped porous biochars with adjustable N-containing groups and porosity were synthesized by one-step pyrolysis of melamine and waste jujube pit in different mass ratios (NBC-x, x represented the mass ratio of melamine to waste jujube pit, x = 4–12) for HCHO adsorption. The HCHO adsorption tests indicated that the insertion of nitrogen-containing species improved the adsorption capacity of pristine biochar (BC). However, after the insertion of excessive nitrogen-containing species, the porosity of the samples significantly decreased due to the blockage of pores, which could be disadvantageous for HCHO adsorption. DFT calculation results showed that N doping (especially pyrrolic-N) significantly increased the maxima of absolute ESP values of the carbonaceous models and consequently enhanced the affinity between polar HCHO and carbonaceous models (varied from −20.65 kJ/mol to −33.26 kJ/mol). Thus, the NBC-8 possessing both substantial nitrogen content (19.81 wt. %) and developed porosity (specific surface area of 223 m²/g) exhibited the highest HCHO uptake of 6.30 mg/g. This was approximately 6.4 times larger than that of BC. This work not only deepens the understanding of the HCHO adsorption mechanism at molecular scale, but also concurrently offers a facile and eco-friendly route of N-doped porous biochar preparation, an efficient technology with high-value utilization of waste biomass resources, and a sustainable method of pollution remediation. Full article

As a critical component of high-temperature proton exchange membrane fuel cells (HT-PEMFCs), the catalytic layer (CL) significantly influences the overall performance of these systems. In this study, a pore-scale lattice Boltzmann (LB) model was established to simulate the multi-component mass transport in the HT-PEMFC catalyst layer. Based on the reconstruction of CL, the transport behavior of phosphoric acid was simulated. The effects of different carbon carrier diameters, porosity values, and Pt/C mass ratios on the transport of phosphoric acid in CL were studied. The distribution of phosphoric acid and air concentration, as well as the electrochemical surface area, was qualitatively and quantitatively analyzed. Finally, the optimal design parameters of CL structure were determined. The results show that, with increases in carbon carrier diameter, porosity, and Pt/C mass ratio, the distribution of phosphoric acid concentration shows an upward trend, and the distribution of air concentration shows a downward trend. The optimal ranges of carbon carrier diameter, porosity, and Pt/C mass ratio are 50–80 nm, 60–70%, and 40–50%, respectively. This study provides a new idea for further understanding the mass transport mechanism in the HT-PEMFC catalyst layer and provides effective suggestions for the optimization design of the HT-PEMFC catalyst layer structure. Full article

The Space Solar Power Station/Satellite (SSPS) is a large-scale space-borne facility intended for the direct collection and conversion of solar energy in the extra-stratospheric region. The optimization of its light collection and conversion (LCC) structures, analysis of dynamic characteristics, and design of attitude control systems represent core technical bottlenecks impeding the advancement of SSPS. To address these issues, this study investigates a novel conceptual line-focusing SSPS. Firstly, a multi-objective collaborative optimization model is developed to optimize the structural parameters of the concentrator and photovoltaic (PV) array. Subsequently, based on the optimized parameters, a coupled multi-body dynamic model is formulated, incorporating gravity-gradient torque and other space-borne disturbance factors. Finally, a distributed Proportional–Integral–Derivative (PID) controller is proposed to achieve three-axis attitude stabilization of the SSPS. Simulation results demonstrate that the light collection efficiency achieves 81.9% with a power density of 4792.24 W/m²; concurrently, a balance between the geometric parameters of the LCC system and the aforementioned key performance indicators is attained, and the proposed controller possesses favorable anti-disturbance performance. Full article

As a widely sourced solid waste rich in metallic elements such as Fe, Zn, Mn and Ca, electric furnace dust serves as a crucial raw material for preparing catalytic materials. This study employed a three-step process—“acid/alkali modification–impregnation–calcination”—to synthesise an electric furnace dust-based magnetic heterogeneous catalyst for biodiesel production. The catalyst prepared via CH₃ONa modification combined with Na₂CO₃ impregnation achieved stable cycling performance at low temperatures, with 14 cycles yielding a consistent conversion exceeding 93.44 wt%, demonstrating exceptional catalytic activity. The CH₃ONa modification generates abundant reactive oxygen species on the furnace dust surface, facilitating the binding of hydroxyl oxygen from the active component (Na⁺) to the modified surface (EFD/CH₃ONa) and thereby anchoring the active species. However, the decline in catalytic performance of the Na₂CO₃&(EFD/CH₃ONa) catalyst after calcination at 600 °C (yield decreasing to 69.77 wt% after 11 stable cycles) was attributed to the detachment and agglomeration of the active component sodium at elevated temperatures. This paper employed electric furnace dust as feedstock to synthesise highly active and stable magnetic multiphase catalysts, thereby not only providing an environmentally sound pathway for industrial solid waste recycling but also offering novel insights for the industrial-scale production of biodiesel. Full article

Zearalenone (ZEN) poses serious risks to human and animal health. Compared with physical and chemical methods, microbial transformation offers a safer and more sustainable strategy for ZEN detoxification. The yeast Hannaella zeae, isolated from the Qinghai–Tibet Plateau, showed the highest ZEN removal efficiency among 11 strains, achieving an 85.87% transformation rate within 36 h. Optimal conditions for ZEN transformation were determined by varying culture time, temperature, and pH. The products were putatively identified as zearalenone-14-β-D-glucopyranoside (C₂₄H₃₂O₁₀) and zearalenone-16-β-D-glucopyranoside (C₂₄H₃₂O₁₀) by UHPLC-Q-Orbitrap-HRMS. The safety of the mixed culture medium extract was further evaluated using a Caenorhabditis elegans model, showing significantly lower toxicity than untreated ZEN. H. zeae maintained high transformation efficiency under low temperature (57.48%) and acidic stress (47.10%), supported by active antioxidant enzymes (SOD, CAT, APX, GPx) and stress metabolites (trehalose, proline). Overall, this study identifies H. zeae as a promising, stress-tolerant biocontrol agent and elucidates its glycosylation-based detoxification mechanism, providing a foundation for future application in real food and feed systems. Full article

Farmland soil water-soluble organic carbon (WSOC), serving as a labile carbon substrate for microbial utilization, demonstrates pronounced sensitivity to land-use modifications and agricultural management practices. This study systematically investigated the impacts of long-term straw incorporation frequencies—including annual (S-1), biennial (S-2), and triennial (S-3) return patterns—on WSOC distribution across 0–20 cm and 20–40 cm soil profiles. Through the integration of three-dimensional excitation–emission matrix (EEM) fluorescence spectroscopy with parallel factor analysis (PARAFAC), we elucidated structural characteristics and humification dynamics associated with different incorporation regimes. The results showed a depth-dependent WSOC distribution pattern with higher concentrations in surface soils (0–20 cm: 261.2–368.9 mg/kg) compared to subsurface layers (20-40 cm: 261.8–294 mg/kg). Straw incorporation significantly increased WSOC content in the 0–20 cm of 16.9%~21.7% and 20–40 cm soil layers of 6.2%~12.3%. Biennial return had the lowest WSOC/SOC ratio, indicating enhanced stability of the soil organic carbon pool. Spectral indices—including the fluorescence index (FI, 1.59~1.69), biological index (BIX, 0.90~0.95), and humification index (HIX, 0.64~0.74)—collectively indicated that WSOC predominantly consisted of microbially processed organic matter with a low degree of humification. PARAFAC modeling resolved two fluorescent components: C1 (humic acid-like substances, 47.4–50.4%), C2 (soluble microbial metabolites, 49.6–52.6%). This systematic investigation provides mechanistic insights into how straw management temporality regulates both quantity and quality of labile carbon pools in agricultural ecosystems. Full article

Biohydrogen production can be derived from low-value lignocellulosic biomass; however, in many biohydrogen producing systems, xylose is utilized less efficiently than glucose, which limits overall substrate conversion. To address this issue, Fe/Mn-modified biochar was employed to enhance dark fermentation of glucose–xylose mixed sugars, and its performance was compared with other inoculum treatments. The biochar addition achieved a hydrogen yield of 2.57 ± 0.10 mol-H₂/mol-sugar, representing 14.6% enhancement over untreated controls, while enabling complete substrate utilization across varying xylose proportions. Biochar supplementation also reduced the lag phase by 24.4% and increased hydrogen productivity by 47.3% in mixed-sugar cultivation. Integrated analyses of the experimental data revealed the dual role of Fe/Mn-modified biochar in constructing conductive extracellular polymeric substance networks and directing metabolic flux toward high-yield butyrate pathways. This work establishes Fe/Mn-biochar as a multifunctional microbial engineering tool that alleviates carbon catabolite repression and promotes the enrichment of hydrogen-producing bacteria (HPB), thereby providing a practical and effective strategy for enhanced biohydrogen production from lignocellulosic biomass. Full article