Search Results (44)

Bupleurum scorzonerifolium Willd. is a perennial herbaceous plant of the genus Bupleurum in the Apiaceae family. Also known as red Bupleurum, it is mainly distributed in Northeast China, North China and other regions and is a commonly used medicinal plant. It is difficult for the wild plant resources of Bupleurum scorzonerifolium Willd. to meet the market demand. In artificial cultivation, there are problems such as a low yield per plant, low quality, weakened stress resistance and variety degradation. The contents of bioactive components and metabolites in traditional Chinese medicinal materials vary significantly across different growth years. The growth duration directly impacts their quality and clinical efficacy. Therefore, determining the optimal growth period is one of the crucial factors in ensuring the quality of traditional Chinese medicinal materials. In this study, Gas Chromatography–Mass Spectrometry (GC-MS) and High-performance liquid chromatography (HPLC) were comprehensively applied to analyze the metabolically differential substances in different parts of Bupleurum scorzonerifolium Willd. By comparing the compositions and content differences of chemical components in different growth years and different parts, the chemical components with significant differences were accurately screened out. In order to further explore the dynamic change characteristics and internal laws of metabolites, a metabolic network was constructed for a visual analysis and, finally, to see the optimal growth years of Bupleurum scorzonerifolium Willd. This result showed that with the accumulation of the growth cycle, the height, root width, fresh mass and saikosaponins content of Bupleurum scorzonerifolium Willd. increased year by year. Except for sodium and calcium elements in the main shoot, the other elements were significantly reduced. In addition, 59 primary metabolites were identified by GC-MS, with the accumulation of the growth cycle, the contents of organic acids, sugars, alcohols and amino acids gradually decreased, while the contents of alkyl, glycosides and other substances gradually increased. There were 53 positive correlations and 18 negative correlations in the triennial Bupleurum scorzonerifolium Willd. grid, all of which were positively correlated with saikosaponins. Therefore, the triennial Bupleurum scorzonerifolium Willd. was considered to be the suitable growth year. It not only provided a new idea and method for the quality evaluation of Bupleurum scorzonerifolium Willd., but also provided a scientific basis for the quality control of Chinese herbs. Full article

Neuroinflammation is involved in the development of depression and may induce depression-like behaviors by affecting metabolism through interactions with circadian rhythms. As the hub of metabolism, mitochondria are regulated by various types of metabolism and release signals that regulate cellular functions. In this study, we performed transcriptomic analysis of the hippocampus of IL-33-overexpressing mice to provide new ideas to explore the pathogenesis of inflammation-mediated depression at the transcriptional level. Male C57BL/6J mice and IL-33-overexpressing mice were subjected to behavioral tests. The hippocampus was extracted during the light or dark period, and differential gene expression analysis was conducted using RNA sequencing. Differential gene enrichment analysis was performed, as well as multilayered analysis of mitochondrial transcriptional rhythms by integrating the regulatory networks and Mito 3.0 database. The results were further verified using RT-qPCR. IL-33-overexpressing mice exhibited depressive behaviors associated with rhythmic disorders and shortened circadian cycles. Differential KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis showed that the top 20 pathways with the lowest p-values included mood-related, immune-related, and circadian rhythm-related pathways. Differential gene GO (Gene Ontology) enrichment analysis showed that 20 of the top 30 pathways with the lowest p-values were related to metabolism. Transcriptome data from IL-33-overexpressing mice showed that the mitochondrial-encoded subunit of the oxidative respiratory complex showed predominantly increased expression during the light period. Metabolic disorders and disrupted mitochondrial transcriptional rhythm were also observed. Weighted gene correlation network analysis showed that the circadian cycle is associated with depression-like behavior disorders. Network analysis showed that circadian-related genes were enriched in mitochondrial pathways related to metabolism and oxidative phosphorylation. Multilayer analysis of mitochondrial transcriptional rhythms using the mitochondrial database Mito 3.0 revealed that mitochondrial dynamics and surveillance pathways were the most enriched. The depressive behavior in mice caused by long-term IL-33 stimulation may be related to changes in the transcriptional rhythms of metabolism-related genes and the interaction between mitochondria and clock genes. This suggests that mitochondrial transcriptional rhythms are central to the pathogenesis of microinflammation-induced depression, further supporting the potential of mitochondria as a target for the prevention and treatment of depression. Full article

In this study, the effects of variations in the height ($h$) and bottom radius ($r$) of black silicon microstructures on their absorptance and photoelectric response efficiency were analyzed. By using the relation $\cot {\displaystyle \frac{\theta }{2}}={\displaystyle \frac{h}{r}}$ to combine the parameters, it was found that changes in morphology affected the absorptance of black silicon microstructures, with $h$ being directly proportional to the absorptance, while $r$ was inversely proportional. A positive correlation was observed between $\cot {\displaystyle \frac{\theta }{2}}$ and absorptance. However, the correlation between $\cot {\displaystyle \frac{\theta }{2}}$ and photoelectric response efficiency was not significant. Through Raman spectroscopy analysis of the samples, it was concluded that as the laser ablation energy density increased, more lattice defects were introduced, weakening the charge carrier transport efficiency. This study further elucidated the mechanism by which microstructural changes impacted the absorptance and energy density of black silicon, providing valuable insights for optimizing its energy density. Full article

This study investigates enhancing the high-temperature oxidation resistance of hot-stamped steels by adding the Cr/Mn/Si elements to form an extremely thin oxide layer. Under low oxygen partial pressure conditions and high Cr content in the matrix, the oxide layer of a 38Cr3MnNbVMo hot-rolled plate containing the Mo element and high Si content was further thinned to 0.6 μm after cooling at 900 °C for 5 min. The structure of the ultra-thin oxide layer consists of Fe₃O₄, Mn oxides, FeCr₂O₄, Cr₂O₃, and Fe₂SiO₄ oxides. Compared to other antioxidant elements, under low oxygen partial pressure conditions, Si is more prone to oxidation, forming ultra-thin (22 nm) Fe₂SiO₄ oxides at the matrix interface. Combined with Cr₂O₃, FeCr₂O₄, and Mn oxides, it collectively inhibits the mutual diffusion of external O ions and matrix Fe ions. Furthermore, the addition of the Mo element improves the oxidation resistance. The synergistic effect of multiple powerful oxidation-resistant elements and oxide products effectively inhibits the growth of the iron oxide scale, enhancing the oxidation resistance of hot-rolled, hot-stamped steel. Full article

The type III secretion system (T3SS) of Rhizobium plays a crucial role during the establishment of the soybean (Glycine max (L.) Merr.)-Rhizobium symbiosis system. Additionally, host-specific nodulation may also depend on the Nops (nodulation outer proteins) secreted by the T3SS of Rhizobium. However, there is limited understanding of the response of soybean genes to Nops. In this study, a NopC mutant, HH103ΩNopC, was constructed from Sinorhizobium fredii HH103 and then utilized to assess the impact of the NopC on nodulation. An RNA-seq analysis revealed that the GmERF5 (Glycine max Ethylene Responsive Factor 5) gene was induced by NopC, which was confirmed by qRT-PCR. Furthermore, an overexpression of the GmERF5 hair-root system was constructed to investigate the effect of GmERF5 on nodulation and its interaction with NopC. Differences in nodule number and nodule dry weight in the overexpression of the GmERF5 hair-root system supported the conclusion that GmERF5 can regulate soybean nodule phenotype via NopC. These results elucidate the genetic mechanisms that regulate nodule phenotype in soybean. Full article

In recent years, with the continuous improvement in the requirements for automobile steel formability, complex phase steel with high formability (CH steel) has been widely used. In the present study, the microstructure of CH steel was regulated using the actual production process as a basis and annealing temperature as a variable, and the effects of annealing temperature on the microstructure, properties, and fracture behavior of CH steel were analyzed. As the annealing temperature increases, the ferrite content decreases from 36.3% to 0, the martensite content decreases from 49.3% to 8.8%, the bainite content increases from 11.9% to 87.1%, and the retained austenite content first increases and then decreases within the range of 2.5~5.1%. Consequently, the tensile strength shows a decreasing trend, the yield strength first decreases and then increases, and the total elongation and the hole expansion ratio first increase and then decrease. The deformation coordination of each phase gradually becomes better, and the voids and cracks in the tensile and hole expansion samples expand along the ferrite and martensite or martensite/austenite (M/A) island interface, transforming into the bainitic ferrite and martensite or M/A islands. The test steel’s best tensile and hole expansion properties occur at annealing temperatures of 940 °C. Full article

To realize unmanned aerial vehicle (UAV) situation assessment, a Bayesian network (BN) for situation assessment is established. Aimed at the problem that the parameters of the BN are difficult to obtain, an improved whale optimization algorithm based on prior parameter intervals (IWOA-PPI) for parameter learning is proposed. Firstly, according to the dependencies between the situation and its related factors, the structure of the BN is established. Secondly, in order to fully mine the prior knowledge of parameters, the parameter constraints are transformed into parameter prior intervals using Monte Carlo sampling and interval transformation formulas. Thirdly, a variable encircling factor and a nonlinear convergence factor are proposed. The former and the latter enhance the local and global search capabilities of the whale optimization algorithm (WOA), respectively. Finally, a simulated annealing strategy incorporating Levy flight is introduced to enable the WOA to jump out of the local optimum. In the experiment for the standard BNs, five parameter-learning algorithms are applied, and the results prove that the IWOA-PPI is not only effective but also the most accurate. In the experiment for the situation BN, the situations of the assumed mission scenario are evaluated, and the results show that the situation assessment method proposed in this article is correct and feasible. Full article

Metal magnetic memory (MMM) is a nondestructive testing technology based on the magnetomechanical effect, which is widely used in the qualitative detection of stress concentration zones for welded joints. However, there is inevitable residual stress after welding, which brings the bottleneck of quantitative identification between the weld residual stress concentration and the early hidden damage. In order to overcome the bottleneck of quantitative identification of weld defect levels with MMM technology, a modified maximum likelihood estimation (MLE) MMM quantitative identifying model is first proposed. The experimental materials are Q235B welded plate specimens. Fatigue tension experiments were operated to find the MMM feature laws of critical hidden crack by comparing with synchronous X-ray detection results. Six MMM characteristic parameters, which are, ΔH_p(x), G_x^max, Z_x^max, ΔH_p(y), G_y^max and Z_y^max, are extracted corresponding to the normal state, the hidden crack state and the macroscopic crack, respectively. The MLE values of the six parameters are obtained by the kernel density functions with optimized bandwidth from the view of mathematical statistics. Furthermore, the modified MLE MMM quantitative identifying model is established based on D–S theory to overcome the partial overlap of MLE values among different defect levels, of which the uncertainty is as low as 0.3%. The verification result from scanning electron microscopy (SEM) is consistent with the prediction of the modified MLE MMM model, which provides a new method for quantitative identification of weld defect levels. Full article

Multi-layer flux-barrier combined-pole permanent-magnet synchronous machines (MLFB-CP-PMSMs) are especially suitable for machines used in electrical vehicles (EVs), as they represent a tradeoff between electromagnetic performance and the consumption of high-priced rare-earth permanent magnets (PM). In this paper, magnetic pole equivalence and performance analyses of the MLFB-CP-PMSM are investigated. Firstly, three types of PM arrangements of combined poles are introduced, namely, parallel, series and series–parallel. Then, the magnetic circuit model and magnetic pole equivalence principle of MLFB-CP-PMSMs with different PM arrangements are analyzed. After that, the accuracy of the equivalence method is studied by comparing the machine electromagnetic performance before and after equivalence. Finally, the MLFB-CP-PMSM’s performance, including the loss, efficiency and electromagnetic torque, is analyzed. The results prove that the MLFB-CP-PMSM has the advantage of high efficiency, and the equivalence method can retain precision when the MLFB-CP-PMSM armature reaction degree varies. Full article

Percolation experiments were conducted on coal samples with various fracture lengths and inclination angles under different stress conditions using a gravity-loaded rock percolation test device. The goals of these experiments are (1) to improve the technology for protecting water resources while mining coal and (2) to enhance the research on how the size effects of fracture affect seepage. A three-dimensional seepage model was constructed using COMSOL numerical simulation software for larger fracture lengths ranging from 1 to 30 m to investigate the seepage pattern under the coupling of fracture roughness, fracture width, and other factors. Multiple regression analysis was used to investigate the effects of different factors on seepage from large and small fractures independently. The results show that, under laboratory conditions, for fracture lengths 10–70 mm (small length), permeability increases non-linearly with an increase in fracture length, and the overall increase is approximately 1.8 times. Whereas, for fracture lengths of 1–30 m (large length) in the simulation, permeability decreases and then increases with an increase in fracture length, and the overall change is approximately 0.03 times. The permeability varies in three stages (1–8 m obvious change, 8–23 m stabilization, 23–30 m stability) under different fracture lengths, widths, and roughness conditions. Acritical size was found to exist. The effect of fracture length on large length fracture seepage and small length fracture seepage was further verified by parameter sensitivity. The results of this study further reveal the mechanism of fracture seepage under coupling of fracture geometry size stress. Full article

Nanoscale fluorescence emitters are efficient for measuring biomolecular interactions, but their utility for applications requiring single-unit observations is constrained by the need for large numerical aperture objectives, fluorescence intermittency, and poor photon collection efficiency resulting from omnidirectional emission. Photonic crystal (PC) structures hold promise to address the aforementioned challenges in fluorescence enhancement. In this review, we provide a broad overview of PCs by explaining their structures, design strategies, fabrication techniques, and sensing principles. Furthermore, we discuss recent applications of PC-enhanced fluorescence-based biosensors incorporated with emerging technologies, including nucleic acids sensing, protein detection, and steroid monitoring. Finally, we discuss current challenges associated with PC-enhanced fluorescence and provide an outlook for fluorescence enhancement with photonic-plasmonics coupling and their promise for point-of-care biosensing as well monitoring analytes of biological and environmental relevance. The review presents the transdisciplinary applications of PCs in the broad arena of fluorescence spectroscopy with broad applications in photo-plasmonics, life science research, materials chemistry, cancer diagnostics, and internet of things. Full article

Co-hydrothermal carbonization (Co-HTC) of sewage sludge (SS) and corn straw (CS) for fuel preparation is a waste treatment method that reduces the pre-treatment cost of solid waste and biomass fuel. Based on the response surface methodology (RSM), a test was designed to prepare SS and CS hydrochars using a hydrothermal high-pressure reactor. The test examined the higher heating value (HHV) and the concentrations of alkali metals and alkaline earth metals (AAEMs) and Cl. The HHV of SS-hydrochar decreased with an increase in reaction temperature, but that of CS-hydrochar increased. The yield of CS-hydrochar was at 26.74–61.26%, substantially lower than that of SS-hydrochar. Co-hydrochar has the advantages of HHV and an acceptable yield. The HHV of co-hydrochar was 9215.51–12,083.2 kJ/kg, representing an increase of 12.6–47.6% over single component hydrochar, while the yield of co-hydrochar was 41.46–72.81%. In addition, the stabilities of AAEM and Cl in the co-hydrochar were Mg > Ca > K > Na > Cl. SS and CS had a synergistic effect on dechlorination efficiency (DE), which had a negative effect on the removal efficiency (RE) of Ca and Na. The optimal hydrocharization conditions were a temperature of approximately 246.14 °C, a residence time of approximately 90 min, and a mixing ratio of SS–CS of approximately 57.18%. The results offer a way to utilize SS and CS by Co-HTC and convert them into low-chlorine and low-alkali fuel, thus pushing the improvement of this promising waste-to-energy technology. Full article

The progression of agricultural production, ever-increasing industrialization, population boom, and more water-concentrated lifestyles has placed a severe burden on Yellow River Basin’s existing water resources, particularly in the current century. In the context of resource and environmental constraints, improving the green efficiency of agricultural water use (AWGE) is an important measure for alleviating the shortage of water resources as well as meeting the intrinsic requirement to promote the green transformation and upgrading of agriculture. This study used the Super Slack-Based Measure (Super-SBM) to measure the AWGE of 87 regions in the Yellow River Basin from 2000 to 2019. Based on spatial and temporal perspectives, it applied Exploratory Spatial Data Analysis (ESDA) to explore the dynamic evolution and regional differences in AWGE. Then, this study used a spatial econometric model to analyze the main factors that influence AWGE in the Yellow River Basin. The results show that, firstly, the AWGE of the Yellow River Basin shows a steady upward trend from 2000 to 2019, but the differences among regions were obvious. Secondly, the AWGE showed an obvious spatial autocorrelation in the Yellow River Basin and showed significant high–high and low–low agglomeration characteristics. Thirdly, rural per capita disposable income and effective irrigation have a positive influence on AWGE, while rural labor transfer, the input intensity of agricultural machinery and water structure have a negative influence. The spatial econometric model regression results show that the influence factors of AWGE in the Yellow River Basin showed significant spatial spillover effects and spatial heterogeneity in their effect. Finally, when improving AWGE in the Yellow River Basin, plans should be formulated according to local conditions. The results of this study can provide new ideas on the study of AWGE in the Yellow River Basin and provide references for the formulation of regional agricultural water resource utilization policies as well. Full article

The void of the cracked rock mass of the goaf is the main water storage space of underground reservoirs, which is in a time-space dynamic evolution process. Before the formation of the underground reservoir, the water storage space was primarily affected by disturbances. After the safe operation of the coal mine underground reservoir, the water level of the mine rises and falls repeatedly and the water storage space is affected by the water-rock interaction. To study the void evolution law of a cracked rock mass under mining disturbance and the compaction and void deformation characteristics of caving gangue under the effect of the water-rock interaction, a simulation test of a coal mine underground reservoir is conducted. Furthermore, the rupture motion law and movement deformation characteristics of the overburden during coal mining are analyzed. The digital image method and fractal theory are introduced to describe the fractal characteristics of the rock mass void of the caving zone, fracture zone, and entire goaf during the mining process. Five prototype gangue samples with different immersion times are prepared with the same grain size grading as the similar model caving gangue. The influence of the immersion times on the compaction characteristics and evolution law of the void rate of the gangue are also studied. Based on the parameter fitting method, the stress–strain relationship equation of the gangue sample and void rate-stress relationship equation of the cylindrical gangue sample, considering the influence of the immersion times, are constructed. The results show that the overburden of the model is of a “two zone” structure and the entire structure moves and sinks asymmetrically in a “∩” shape. As the advancing distance of the working face increased, the fractal dimensions of the rock mass void of the caving zone and entire goaf increased logarithmically, and the fractal dimension of the rock mass void of the fracture zone first increased rapidly (60–80 cm) and then decreased linearly (80–200 cm). As the immersion time increased, the saturated moisture content and density of the gangue samples increased logarithmically and exponentially, respectively. Under the same stress, the strain of the gangue sample increased gradually, and the void rate decreased gradually (except for the initial loading). Full article

A kind of bent multimode fiber (MMF) vector magnetic sensor based on surface plasmon resonance (SPR) was proposed. By plating gold film on the curved part of the bent multimode fiber, the surface plasmon mode (SPM) was excited via a whispering gallery mode (WGM). Fabricating the structure only required bending the fiber and plating it with gold, which perfectly ensured the integrity of the fiber and made it more robust compared with other structures. The sensor used magnetic fluid (MF) as the magnetically sensitive material. Through monitoring the shift of the surface plasmon resonance dip, the as-fabricated sensor not only had a high magnetic field intensity sensitivity of 9749 pm/mT but could also measure the direction of a magnetic field with a high sensitivity of 546.5 pm/°. The additional advantages of the proposed sensor lay in its easy fabrication and good integrity, which make it attractive in the field of vector-magnetic-field sensing. Full article