Search Results (3,297)

Harvest-disrupting rain events (HDREs) are prolonged cloudy–rainy spells during winter wheat maturity that impede harvesting and drying, induce pre-harvest sprouting and grain mould, and threaten food security in the Huang–Huai–Hai Plain (HHHP), China’s core winter wheat region. Using daily meteorological records (1960–2019), remote sensing-derived land-use data and topography, we develop a hazard–exposure–vulnerability framework to quantify HDRE risk and its drivers at 1 km resolution. Results show that HDRE risk has increased markedly over the past six decades, with the area of medium-to-high risk rising from 26.9% to 73.1%. The spatial pattern evolved from a “high-south–low-north” structure to a concentrated high-risk belt in the central–northern HHHP, and the risk centroid migrated from Fuyang (Anhui) to Heze (Shandong), with an overall displacement of 124.57 km toward the north–northwest. GeoDetector analysis reveals a shift from a “humidity–temperature dominated” mechanism to a “sunshine–humidity–precipitation co-driven” mechanism; sunshine duration remains the leading factor (q > 0.8), and its interaction with relative humidity shows strong nonlinear enhancement (q = 0.91). High-risk hot spots coincide with low-lying plains and river valleys with dense winter wheat planting, indicating the joint amplification of meteorological conditions and underlying surface features. The results can support regional decision-making for harvest-season early warning, risk zoning, and disaster risk reduction in the HHHP. Full article

China is the world’s third-largest sugarcane producer. When mechanically harvested sugarcane enters the sugar mill, impurity rate detection is required. However, due to the piling up of sugarcane, significant errors may occur in the detection results. Therefore, this research addresses the issue of low accuracy in machine vision detection due to the dense stacking of sugarcane. An innovative graded device was developed, featuring a three-stage progressive geometric constraint system with roller-belt gaps of 100 mm, 45 mm, and 33 mm, alongside differential traction with speed ratios of 3:1, 4:1, and 5:1. Utilizing the normal distribution characteristic for the diameter of 500 sugarcane stalks, the gap parameters were refined through a dynamic stiffness model. Through power validation and multi-factor orthogonal experiments, the study uncovered the interactive influences of sugarcane weight, primary conveyor belt speed, and speed ratio on the single-layer rate and area ratio. Our findings indicate that sugarcane weight is the primary determinant of the material’s single-layer rate, while the speed ratio is crucial for managing sugarcane distribution density, more so than the primary conveyor belt speed. Notably, increasing the speed ratio from 3:1 to 5:1 results in a decrease in area ratio from 26.8% to 22.0%. After utilizing the graded differential device, the average accuracy of machine vision detection achieved 94.90%, with only two misidentifications on average. In comparison to the control group, detection accuracy improved by 26.93%, misidentifications dropped by about 81.80%, and detection speed was recorded at 55.5 ms. These outcomes confirm that the device not only enhances detection accuracy but also significantly lowers the misidentification rate, thereby creating a stable, clear, and efficient detection environment. Full article

Despite the advances in medical therapies for treating myocardial infarction (MI), morbidity and mortality rates remain high. Following MI, increased methylglyoxal (MG) production leads to the accumulation of advanced glycation end-products (AGEs), which contribute to adverse remodeling and to the deterioration of cardiac function. We previously reported that an injectable collagen type I hydrogel improves the repair and function of mouse hearts post-MI. Notably, we observed that the injected hydrogel was a target for MG-AGE glycation, and that there were less MG-modified proteins in the myocardium. In this study, we further evaluated this protective mechanism by pre-glycating the hydrogels and assessing their therapeutic efficacy for treating MI. In vitro experiments showed that the viability of macrophages was reduced when cultured with the glycated hydrogel in the presence of MG. In vivo, female C57BL/6 mice were randomly assigned to receive intramyocardial injections of one of three treatments: phosphate-buffered saline, normal collagen hydrogel, or MG-glycated hydrogel. After 28 days, echocardiography was performed to evaluate cardiac function, and hearts were harvested for immunohistochemistry. Our results showed that the MG-glycated hydrogel had a reduced treatment effect (greater scar size, fewer wound-healing macrophages, less viable myocardium and decreased cardiac function) compared to mice that received the normal collagen hydrogel. In summary, this study demonstrates that the ability of the collagen hydrogel to act as a target for glycation and remove MG from the environment contributes to its therapeutic effect in treating the post-MI heart. Full article

Background: Dorsal pedicle skin flap application is a cover procedure frequently used by plastic surgeons to cover acute and chronic wounds, but preventing postoperative flap loss and disruption of the wound healing process has not yet been achieved. Injecting boron nitride during the transfer of the dorsal pedicle skin flap may increase flap survival. Objective: This study investigated the efficacy of hexagonal boron nitride (hBN) injection in enhancing the survival of pedicled skin flaps harvested from the dorsal region of rats. Method: This study employed an experimental design. A total of 24 Wistar albino rats were divided into three groups of eight each: Control (Group 1), Sham (Group 2), and Experimental (Group 3). A 27 cm² (3 cm × 9 cm) dorsal skin flap with a proximal pedicle was harvested at the level of the iliac crests, with the flap extending cranially, and then reattached. During flap transfer, no intervention was performed in Group 1, physiological saline was injected into Group 2, and hBN was injected into Group 3. After a certain period of time, sections were taken from the proximal pedicle skin flap on the dorsal side of the rats, and histochemical examination and biochemical analyses were performed on these sections. Results: In this study, it was observed that the epithelial integrity of the epidermal layer was disrupted and the epithelium was thinned in places in Group 2. Compared to Group 1, collagen fiber density was lower, collagen fiber arrangement was irregular, and mast cell density was higher. In Group 3, similar to Group 1, the epidermis and dermis layers were composed of multilayered flat keratinized epithelium, collagen fiber density was high and had a regular arrangement, and elastic fiber structure was of normal density. The TGF-β1 and MMP-1 measurement results for the three groups were compared, and no statistically significant difference was found between the groups (p > 0.05). Conclusions: The results of this study support the benefit of hBN injection in improving flap survival after proximal pedicle skin flap application on the dorsal side of rats. Although the improved healing of skin layers after flap transfer with hBN suggests that it supports cell proliferation, the mechanism of action and pathophysiology remain unclear. Full article

Enhancing photosynthetic efficiency represents a key approach for improving crop biomass, with its translation into higher grain yield being contingent upon the efficiency of photosynthate partitioning toward harvestable organs. The Rubisco small subunit (RbcS) gene family plays an essential role in this process by stabilizing and regulating Rubisco assembly and activity during photosynthesis. In this study, we identified 61 RbcS genes across B. napus, B. juncea, and B. carinata, and their diploid progenitors B. rapa, B. nigra, and B. oleracea by genome-wide screening and bioinformatic approaches. Phylogenetic relationships, gene structures, conserved domains, collinearity, cis-regulatory elements, expression profiles, and haplotype variations were systematically investigated, revealing the potential functional role significance and regulatory complexity of RbcS genes in photosynthesis. The results imply that the promoter type of this gene family may belong to light-inducible promoters. Furthermore, while a haplotype analysis provided valuable insights for selecting germplasm with potentially high photosynthetic efficiency, definitive confirmation of their effects requires functional validation. Collectively, our results establish a theoretical foundation for understanding the molecular mechanisms of BnRbcS genes and propose candidate genetic targets for further exploration to enhance photosynthetic performance in rapeseed breeding. Full article

A compliant parallel multi-directional piezoelectric vibration energy harvester (C-MVEH) is proposed based on a 3-RRR compliant parallel mechanism. The energy harvester structure consists of three identical L-shaped beams, whose bending deformation can be equivalent to the rotations of the three joints. In order to achieve greater bending deformation for composite beams, motion flexibility optimization of the mechanism theory is applied to structure the synthesis of the C-MVEH. Meanwhile, to reduce the natural frequencies corresponding to the working modes, the length of the elastic beam is optimized with the maximum natural frequency among the first three modes. In order to verify the excellent performance of the C-MVEH, an electromechanical model, finite element simulations, and experimental studies are carried out. Analysis of the studies reveals that the C-MVEH has three resonance peaks of output voltage within a bandwidth of 7–13 Hz and can output a total voltage of at least 20 V under a small excitation of 0.2 g. The energy harvester can achieve multiple peak output voltages under small excitations in different directions and a wide frequency range. With its outstanding stability, the proposed C-MVEH demonstrates considerable application value in the supplying of power to microenergy electronic devices, such as smart sensors and microactuators. Full article

Real-time detection of fresh corn ear height can provide a basis for dynamic adjustment of harvester header parameters, reducing mechanical damage and improving harvest quality. This study proposes a corn ear height detection model (CEHD). A YOLO-HAMDF network is developed for ear recognition, in which the core modules—TBDA, GLSA, and AQE—respectively suppress background interference, enhance contextual perception, and optimize bounding-box scoring. Depth information is incorporated to filter non-target regions and improve system robustness. In addition, a DI-DeepSORT module is designed for ear tracking, where DBC-Net and IDA-Kalman, respectively, enhance the discriminability of ReID features and enable independent-dimension adaptive noise modeling with smoothed positional updates. Experimental results demonstrate that the proposed CEHD model achieves a mean absolute error (MAE) of only 3.21 ± 0.05 cm under field conditions, indicating strong stability and practical applicability. In summary, this study presents a stable and reliable corn ear height detection system, achieves real-time monitoring of ear height, and provides data support for the dynamic adjustment of header parameters in fresh corn harvesters. Full article

To improve the comprehensive performance of indium oxide (In₂O₃) thermoelectric materials, this study systematically investigates the regulatory effects of tantalum (Ta) doping on their electrical transport characteristics, thermoelectric conversion efficiency, and mechanical properties. The results show that Ta doping achieves synchronous optimization of multiple properties through precise regulation of crystal structure, electronic structure, and microdefects. In terms of electrical transport, the electron doping effect of Ta⁵⁺ substituting In³⁺ and the introduction of impurity levels lead to a continuous increase in carrier concentration; lattice relaxation and impurity band formation at high doping concentrations promote mobility to first decrease and then increase, resulting in a significant growth in electrical conductivity. Although the absolute value of the Seebeck coefficient slightly decreases, the growth rate of electrical conductivity far exceeds the attenuation rate of its square, increasing the power factor from 1.83 to 5.26 μWcm⁻¹K⁻² (973 K). The enhancement of density of states near the Fermi level not only optimizes carrier transport efficiency but also provides electronic structure support for synergistic performance improvement. For thermoelectric conversion efficiency, the substantial increase in power factor collaborates with thermal conductivity suppression induced by lattice distortion and impurity scattering, leading to a leapfrog increase in ZT value from 0.055 to 0.329 (973 K). In terms of mechanical properties, lattice distortion strengthening, formation of strong Ta-O covalent bonds, and dispersion strengthening effect significantly improve the Vickers hardness of the material. Ta doping breaks the bottleneck of mutual property constraints in traditional modification through an integrated mechanism of “electronic structure regulation-carrier transport optimization-multiple performance synergistic enhancement”, providing a key strategy for designing high-performance indium oxide-based thermoelectric materials and facilitating their practical application in the field of green energy conversion. Full article

To address the issue of low efficiency in recovering low-frequency vibration energy during vehicle operation, this paper proposes a piezoelectric energy capture harvester based on wheel vibration. The device employs a parallel configuration of dual cantilever beam piezoelectric transducers in its mechanical structure, with additional mass blocks to optimize its resonant characteristics in the low-frequency range. A synchronous switch energy harvesting circuit was designed. By actively synchronizing the switch with the peak output voltage of the piezoelectric element, it effectively circumvents the turn-on voltage threshold limitations of diodes in bridge rectifier circuits, thereby enhancing energy conversion efficiency. A dynamic model of this device was established, and multiphysics simulation analysis was conducted using COMSOL-Multiphysics to investigate the modal characteristics, stress distribution, and output performance of the energy harvester. This revealed the influence of the piezoelectric vibrator’s thickness ratio and the mass block’s weight on its power generation capabilities. Experimental results indicate that under 20 Hz, 12 V sinusoidal excitation, the system achieves an average output power of 3.019 mW with an average open-circuit voltage reaching 16.70 V. Under simulated road test conditions at 70 km/h, the output voltage remained stable at 6.86 V, validating its feasibility in real-world applications. This study presents an efficient and reliable solution for self-powering in-vehicle wireless sensors and low-power electronic devices through mechatronic co-design. Full article

The manipulator is a key component for harvesting citrus and other fruit crops. A study of the dynamic characteristics and energy consumption modelling of its joints is the foundation for optimising the manipulator’s load parameters and achieving efficient operation. To address the issues of the 6-DOF citrus-picking manipulator’s high degrees of freedom and complex structure, which lead to complex dynamic characteristics and an unclear energy transfer and consumption mechanism, the electromechanical coupling dynamics and energy consumption of the joint system are systematically studied using bond graphs. Firstly, the bond graph model is constructed by combining it with the joint system’s physical structure. On this basis, the corresponding dynamic characteristic state equation and energy consumption model are established. Secondly, the dynamic response and energy consumption characteristics of the joint system are analysed, revealing the system’s energy consumption and dynamic characteristics under different working conditions. Finally, the effectiveness and precision of the proposed model in describing the dynamic behaviour of the joint system and energy consumption are verified through experiments. The model provides a theoretical basis and a new research perspective for optimizing joint parameters, load solutions, and energy efficiency of the harvesting manipulator. Full article

Along the French-English Channel coast, fibre flax is traditionally cultivated in spring during a short window from March to July. However, increasingly frequent and severe spring droughts, driven by climate change, cast doubt on the sustainability of this practice. One possible adaptation, inspired by the winter cultivation of oilseed flax and tested over several years, involves extending the growing cycle by cultivating fibre flax in winter. In this system, seeds are sown in autumn, and the crop is harvested in early June. After four consecutive years of monitoring yield and fibre mechanical properties, a selected spring flax variety was grown both in winter 2022/2023 and in spring 2023 for direct comparison. This period included a mild winter favourable for winter crops, and a spring drought that severely impacted spring crops. Plants from the winter crop produced twice as many fibres at mid-stem height as the spring crop, but the mechanical properties of the elementary fibres remained similar in both. However, the elementary fibres in the lower stems of the winter crop averaged only 15 mm in length, compared to 33 mm for the spring crop, which benefited from higher temperatures. Regarding biochemical composition, lignin content in winter flax scutched fibres was significantly higher than in spring flax, at 4.2% versus 2.7%. Cultivating a spring flax variety in winter is thus feasible under favourable conditions, but the resulting fibres are shorter and more lignified, which may pose technical challenges during spinning and could require separating fibres from the lower stems of winter plants to ensure consistent fibre quality. In the final section of the paper, strategies to adapt flax cultivation to climate change are proposed, drawing on the experimental results and current meteorological projections, providing guidance for optimizing crop performance. Full article

Bamboo rhizomes, the belowground stems of bamboo, play a crucial role in ecosystem functioning and material cycling; however, they have long been regarded as forest residues, receiving limited research attention. This review systematically summarizes current knowledge on the anatomical structure, chemical composition, physical and mechanical properties, and applications of bamboo rhizomes, thereby highlighting their potential for high–value utilization. Based on existing studies, a three-tier framework of rhizome characteristics is proposed: (1) age–driven changes, including lignin deposition, cellulose distribution, and cell wall development; (2) interspecific differences in chemical and anatomical traits, which modulate mechanical performance and durability; and (3) functional differentiation between rhizomes and culms, reflecting adaptation to belowground environments. Within this framework, the structural, chemical, and physicomechanical properties of bamboo rhizomes exhibit tight coupling, thus providing theoretical guidance for species selection, harvesting strategies, and processing. Moreover, bamboo rhizomes have been applied in handicrafts, agricultural organic fertilizers, and composite materials, and they show emerging potential in high-friction functional materials and bio–based composites. Nevertheless, systematic investigations remain limited, particularly regarding structure–property relationships, interspecific performance variability, and optimized processing technologies. Therefore, future research should focus on multidimensional characterization, elucidation of structure–property coupling mechanisms, and development of high–value processing techniques, in order to promote the transformation of bamboo rhizomes into value–added products, thereby supporting green bamboo industry development and the “Bamboo Instead of Plastic” initiative. Full article

Monitoring the health of power lines (PL) is essential for ensuring reliable power delivery, facilitating predictive maintenance, and maintaining a resilient grid infrastructure. Given the extensive length of PL networks, large numbers of wireless sensor nodes must be deployed, often in remote and harsh environments where battery replacement is costly and impractical. To address these limitations, this work proposes a hybrid energy-harvesting approach that combines piezoelectric and photovoltaic (PV) technologies to enable long-term, battery-free PL monitoring. The primary energy source is a compact, tunable, magnetically coupled piezoelectric vibrational energy harvester (VEH) that exploits local magnetic field distribution, inducing mechanical excitation of a cantilever and enabling the harvesting of vibrational energy near the PL at a frequency of 50 Hz. A complementary PV harvester is integrated to ensure operation during power outages or conditions where the piezoelectric excitation is reduced, thereby enhancing system robustness. Electromechanical characterization and a lumped-parameter model show good agreement with experimental results of the proposed VEH. The system is validated both on a PL test bench (5 A–10 A) and through inertial excitation using an electrodynamic shaker, demonstrating stable performance across a wide range of operating conditions. The combined hybrid architecture highlights a promising pathway toward self-sustaining, maintenance-free sensor nodes for next-generation power line monitoring. Finally, we demonstrate the feasibility of using such system for powering a WSN node by comparing the power produced by the proposed system with the power consumption of a potential application. Full article

Triboelectric nanogenerators (TENGs) offer intrinsically high open-circuit voltages in the kilovolt range; however, conventional diode rectifier interfaces clamp the voltage prematurely, restricting access to the high-energy portion of the mechanical cycle and preventing delivery-centric control. This work develops a unified physical basis for contact–separation (CS) TENGs by confirming the consistency of the canonical $V_{oc}$–$C_s$ relation with a dual-capacitor energy model and analytically establishing that both terminal voltage and storable electrostatic energy peak near maximum plate separation. Leveraging this insight, a self-powered gas-discharge-tube (GDT) rectifier bridge is devised to replace two diodes and autonomously trigger conduction exclusively in the high-voltage window without auxiliary bias. An inductive buffer regulates the current slew rate and reduces $I^{2}R$ loss, while the proposed topology realizes two decoupled power rails from a single CS-TENG, enabling simultaneous sensing/processing and actuation. A low-power microcontroller is powered from one rail through an energy-harvesting module and executes an operator-based nonlinear controller to regulate the actuator-side rail via a MOSFET–resistor path. Experimental results demonstrate earlier and higher-efficiency energy transfer compared with a diode-bridge baseline, robust dual-rail decoupling under dynamic loading, and accurate closed-loop voltage tracking with negligible computational and energy overhead. These findings confirm the practicality of the proposed self-powered architecture and highlight the feasibility of integrating operator-theoretic control into TENG-driven rectifier interfaces, advancing delivery-oriented power extraction from high-voltage TENG sources. Full article

Cynanchum thesioides (C. thesioides) is a sand-dwelling edible and medicinal plant whose fruit softens rapidly after harvest, limiting its storage life. In this study, we investigated the efficacy and underlying mechanisms of alternating magnetic field (AMF) treatment as a non-thermal and eco-friendly preservation method for C. thesioides fruit. Freshly harvested fruits were subjected to AMF at varying field intensities (1.07–1.54 mT) and exposure durations (5–25 min). We monitored the physiological indicators (respiration rate, membrane permeability, and firmness) during storage to determine the optimal conditions and performed transcriptome sequencing to identify differentially expressed genes, with qRT-PCR validation of two key cell wall-degrading genes (β-glucosidase (BG) and polygalacturonase (PG)). The results showed that AMF treatment at 1.28 mT for 15 min best maintained the postharvest quality, significantly reducing respiration and membrane leakage while delaying firmness loss. Transcriptomic analysis identified 2480 differentially expressed genes enriched in hormone signaling and cell wall metabolism pathways, and qRT-PCR confirmed that AMF downregulated BG and PG expression, suggesting suppressed cell wall degradation and delayed softening. In conclusion, AMF treatment effectively prolonged the shelf life of C. thesioides by modulating the expression of cell wall-related genes. These findings provide novel insight into magnetic field-induced fruit preservation and support AMF as a green non-thermal postharvest technology. Full article