182 results on '"Li, Xiaopeng"'
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2. Alterations in Physiological Parameters and Secondary Metabolites of Astragalus adsurgens Infected by the Pathogen Alternaria gansuensis.
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Han, Xinyao, Li, Xiaopeng, White, James F., Creamer, Rebecca, Li, Chunjie, and Yu, Binhua
- Abstract
Alternaria gansuensis, a seed-borne fungus of standing milkvetch (Astragalus adsurgens), is the most common pathogen of this plant species and causes yellow stunt and root rot. Although plant resistance to this disease has been identified, a better understanding of the nature of this resistance will help improve and optimize its implementation in standing milkvetch. The effects of A. gansuensis on the physiology of standing milkvetch were assessed in a 4-week study comparing a resistant plant variety, Shanxi, and a susceptible variety, Ningxia. In the first week, there was an obvious decrease in photosynthesis (P) in inoculated plants, especially in the susceptible variety, but there were no changes in stomatal conductance (Sc). From the second week on, P and Sc decreased progressively, and significant stem lesions were observed concomitantly. Water use efficiency (WUE) increased slightly in the second week but then decreased significantly from the third week. Physiological changes observed for the resistant variety of standing milkvetch were less dramatic than those of the susceptible variety. Hyphae were observed around inoculation lesions of the plants. Culture filtrate (CF) of A. gansuensis induced changes in extracellular pH and conductivity, especially in the susceptible variety samples. Tissue integrity changes in the plants correlated with the decrease in P. Secondary metabolite compounds were extracted from the plants and 21 types of compounds were identified. The composition and proportion of secondary metabolites were markedly altered by the pathogen, and these differences may indicate potential mechanisms of disease resistance to A. gansuensis in standing milkvetch. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. A Cost-Effective Strategy to Modify the Electrical Properties of PEDOT:PSS via Femtosecond Laser Irradiation.
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Zhang, Chi, Zhou, Jiayue, Han, Rui, Chen, Cheng, Jiang, Han, Li, Xiaopeng, Peng, Yong, Wang, Dasen, and Wang, Kehong
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FEMTOSECOND lasers ,LIGHT emitting diodes ,ELECTRIC conductivity ,QUANTUM efficiency ,CONDUCTING polymers ,PEROVSKITE - Abstract
Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is a commonly used conductive polymer in organic optoelectronic devices. The conductivity and work function of the PEDOT:PSS are two important parameters that significantly determine the performance of the associated optoelectronic device. Traditionally, some solvents were doped in PEDOT:PSS solution or soaked in PEDOT:PSS film to improve its electrical conductivity, but they damaged the integrity of PEDOT:PSS and reduce the film's work function. Herein, for the first time, we use femtosecond laser irradiation to modify the electrical conductivity and work function of PEDOT:PSS film. We proposed that the femtosecond laser irradiation could selectively remove the superficial insulative PSS, thereby improving the electrical conductivity of the film. The femtosecond laser-irradiated PEDOT:PSS film was further employed as a hole injection layer within cutting-edge perovskite light-emitting diodes (PeLEDs). A maximum luminosity of 950 cd/m
2 was obtained in PeLEDs irradiated by femtosecond laser light in thin films, which is five times higher than that of the controlled device. Moreover, the external quantum efficiency of the devices was also increased from 4.6% to 6.3%. This work paved a cost-effective way to regulate the electrical properties of the PEDOT:PSS film. [ABSTRACT FROM AUTHOR]- Published
- 2024
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4. Dynamic Current-Limitation Strategy of Grid-Forming Inverters Based on SR Latches.
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Zhang, Huajie, Ma, Junpeng, and Li, Xiaopeng
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FAULT currents ,OVERCURRENT protection ,IDEAL sources (Electric circuits) ,MATHEMATICAL models ,SYNCHRONIZATION ,ELECTRIC inverters - Abstract
A grid-forming (GFM) inverter can effectively support active power and reactive power, and the stability problem induced by the low inertia can be thereby alleviated in a power electronics-dominated power system. Yet, the voltage source characteristic presented by the grid-forming inverter induces an overcurrent problem during a short-circuit fault. Furthermore, the time delay induces an inrush current in traditional digital control, triggered by a predefined timing sequence. To address the overcurrent problem of the GFM inverter controlled by the digital controller, the operation characteristics of GFM inverters under grid-voltage drops are investigated, and a mathematical model of the instantaneous fault current is established, which depicts the relationship between the instantaneous fault current's magnitude, grid-voltage drop severity, equivalent output impedance, and current inner-loop response speed. Then, a Set–Reset (SR) latch-based dynamic current limitation with event-triggered control is proposed for the low-voltage ride-through of the GFM inverter. In the proposed method, the current limitation is enabled during grid fault, and the active and reactive powers can be recovered rapidly after fault clearance. Meanwhile, the active and reactive power references are designed to enhance synchronization stability during the grid fault. The proposed method addresses the issue of the repeated switching of virtual impedance during grid fault and achieves rapid power recovery after fault clearance. In addition, the proposed method uses the logic of event triggers to respond to the overcurrent event in real time and realize overcurrent protection. The simulation and experimental results demonstrate the effectiveness of the proposed method in current limitation and active-power recovery after fault clearance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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5. The Aqueous Extract of Hemerocallis citrina Baroni Improves the Lactation-Promoting Effect in Bovine Mammary Epithelial Cells through the PI3K-AKT Signaling Pathway.
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Chen, Jiaxu, Pan, Zhaoping, Li, Qili, Wu, Yanyang, Li, Xiaopeng, Wang, Xue, Hao, Dandan, Peng, Xiaoyu, Pan, Lina, Li, Wei, Wang, Jiaqi, Li, Tao, and Fu, Fuhua
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REVERSE transcriptase polymerase chain reaction ,MILKFAT ,EDIBLE plants ,MAMMARY glands ,MILK supply - Abstract
Insufficient milk supply is a widespread issue faced by women globally and associated with a higher risk of health problems in infants and mothers. Hemerocallis citrina Baron, commonly known as daylily, is a perennial edible plant often used in traditional Asian cuisine to promote lactation. However, the active compound(s) and mechanism of its lactation-promoting effect remain unclear. This study aimed to confirm the traditional use of daylily in promoting lactation and investigate its potential active components and underlying molecular mechanisms. Our results showed that the aqueous extracts of H. citrina Baroni (HAE) significantly enhanced milk production, and the serum levels of lactation-related hormones, and promoted mammary gland development in lactating rats, as well as increased the levels of milk components in bovine mammary epithelial cells (BMECs) (p < 0.05). UHPLC-Q-Exactive Orbitrap-MS analysis revealed that hexamethylquercetin (HQ) is the representative flavonoid component in HAE, accounting for 42.66% of the total flavonoids. An integrated network pharmacology and molecular docking analysis suggested that HQ may be the potential active flavonoid in HAE that promotes lactation, possibly supporting lactation by binding to key target proteins such as STAT5A, PIK3CA, IGF1R, TP53, CCND1, BCL2, INS, AR, and DLD. Cell experiments further demonstrated that HQ could promote cell proliferation and the synthesis of milk proteins, lactose, and milk fat in BMECs. Transcriptomic analysis combined with a quantitative reverse transcription polymerase chain reaction (RT-qPCR) revealed that both HAE and HQ exert a lactation-promoting function mainly through regulating the expression of key genes in the PI3K-Akt signaling pathway. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Modeling and Rotation Control Strategy for Space Planar Flexible Robotic Arm Based on Fuzzy Adjustment and Disturbance Observer.
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Liu, Jiaqi, Li, Xiaopeng, Yin, Meng, Wei, Lai, and Wang, Haozhe
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SPACE robotics , *TRANSFER functions , *TORQUE , *ROTATIONAL motion , *ROBOTICS - Abstract
In precise space operation tasks, the impact of disturbing torques on the space flexible robotic arm (SFRA) cannot be ignored. Besides, the slender structure of the SFRA is very likely to generate vibration of the robotic arm. These are all potential hidden dangers in space safety. To quantify the potential risk, an accurate dynamics model of the SFRA considering the disturbing torque is built by Lagrange principle and the assumed modal method (AMM). Moreover, the effects of the disturbing torque, modal order and nonlinear terms on the deformation accuracy of the SFRA are compared. It is observed that the simplified dynamics model with neglecting the nonlinear terms (NNTs) has a high model accuracy and be easily solved. Therefore, the NNTs simplified model is chosen for deriving the transfer function of the SFRA. The parameters of the PI controller are adjusted in real time based on fuzzy rules to reduce the tracking error in the SFRA. In addition, the disturbance observer is designed to observe and compensate of the disturbance torque in the SFRA. The control method of adjusting controller parameters with fuzzy rules based on the disturbance observer greatly improves the rotational control accuracy of the SFRA. Finally, the validity of aforementioned control strategy is confirmed by simulation analysis and experimental results. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Design and Computational Validation of γ-Ray Shielding Effectiveness in Heavy Metal/Rare Earth Oxide–Natural Rubber Composites.
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Liu, Yongkang, Li, Xiaopeng, Yin, Yilin, Li, Zhen, Yao, Huisheng, Li, Zenghe, and Li, Heguo
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ATTENUATION coefficients , *MASS attenuation coefficients , *BACKGROUND radiation , *RADIATION shielding , *MONTE Carlo method - Abstract
This study involved the preparation of natural rubber-based composites incorporating varying proportions of heavy metals and rare earth oxides (Sm2O3, Ta2O5, and Bi2O3). The investigation analyzed several parameters of the samples, including mass attenuation coefficients (general, photoelectric absorption, and scattering), linear attenuation coefficients (μ), half-value layers (HVLs), tenth-value layers (TVLs), mean free paths (MFPs), and radiation protection efficiencies (RPEs), utilizing the Monte Carlo simulation software Geant4 and the WinXCom database across a gamma-ray energy spectrum of 40–150 keV. The study also compared the computational discrepancies among these measurements. Compared to rubber composites doped with single-component fillers, multi-component mixed shielding materials significantly mitigate the shielding deficiencies observed with single-component materials, thereby broadening the γ-ray energy spectrum for which the composites provide effective shielding. Subsequently, the simulation outcomes were juxtaposed with experimental data derived from a 133Ba (80 keV) γ-source. The findings reveal that the simulated results align closely with the experimental observations. When compared to the WinXCom database, the Geant4 software demonstrates superior accuracy in deriving radiation shielding parameters and notably enhances experimental efficiency. [ABSTRACT FROM AUTHOR]
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- 2024
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8. An Experimental Study of the Acoustic Signal Characteristics of Locked-Segment Damage Evolution in a Landslide Model.
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Zhu, Xing, Chen, Hui, Wu, Zhanglei, Yang, Shumei, Li, Xiaopeng, and Li, Tiantao
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ACOUSTIC emission ,CRACK propagation (Fracture mechanics) ,SIGNALS & signaling ,MICROCRACKS ,CLASSIFICATION ,LANDSLIDES - Abstract
Three-section landslides are renowned for their immense size, concealed development process, and devastating impact. This study conducted physical model tests to simulate one special geological structure called a three-section-within landslide. The failure process and precursory characteristics of the tested samples were meticulously analyzed using video imagery, micro-seismic (MS) signals, and acoustic emission (AE) signals, with a focus on event activity, intensity, and frequency. A novel classification method based on AE waveform characteristics was proposed, categorizing AE signals into burst signals and continuous signals. The findings reveal distinct differences in the evolution of these signals. Burst signals appeared exclusively during the crack propagation and failure stages. During these stages, the cumulative AE hits of burst signals increased gradually, with amplitude rising and then declining. High-amplitude burst signals were predominantly distributed in the middle- and high-frequency bands. In contrast, cumulative AE hits of continuous signals escalated rapidly, with amplitude monotonously increasing, and high-amplitude continuous signals were primarily distributed in the low-frequency band. The emergence of burst signals and high-frequency AE signals indicated the generation of microcracks, serving as early-warning indicators. Notably, the early-warning points of AE signals were detected earlier than those of video imagery and MS signals. Furthermore, the early-warning point of burst signals occurred earlier than those of continuous signals, and the early-warning point of the classification method preceded that of overall AE signals. [ABSTRACT FROM AUTHOR]
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- 2024
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9. Characteristic Extraction and Assessment Methods for Transformers DC Bias Caused by Metro Stray Currents.
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Wang, Aimin, Lin, Sheng, Wu, Guoxing, Li, Xiaopeng, and Wang, Tao
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STRAY currents ,DC transformers ,DISTRIBUTION (Probability theory) ,VIBRATION tests ,WEIGHING instruments ,ELECTRIC transformers - Abstract
Metro stray currents flowing into transformer-neutral points cause the high neutral DC and a transformer to operate in the DC bias state.Because neutral DC caused by stray current varies with time, the neutral DC value cannot be used as the only characteristic indicator to evaluate the DC bias risk level. Thus, unified characteristic extraction and assessment methods are proposed to evaluate the DC bias risk of a transformer caused by stray current, considering the signals of transformer-neutral DC and vibration. In the characteristic extraction method, the primary characteristics are obtained by comparing the magnitude and frequency distributions of transformer-neutral DC and vibration with and without metro stray current invasion. By analyzing the correlation coefficients, the final characteristics are obtained by clustering the primary characteristics with high correlation. Then, the magnitude and frequency characteristics are extracted and used as indicators to evaluate the DC bias risk. Moreover, to avoid the influence of manual experience on indicator weights, the entropy weight method (EWM) is used to establish the assessment model. Finally, the proposed methods are applied based on the neutral DC and vibration test data of a certain transformer. The results show that the characteristic indicators can be extracted, and the transformer DC bias risk can be evaluated by using the proposed methods. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Mitigation Strategy of Neutral-Point DC for Transformer Caused by Metro Stray Currents.
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Wang, Aimin, Lin, Sheng, Wu, Guoxing, and Li, Xiaopeng
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DC transformers ,STRAY currents ,MONTE Carlo method ,ELECTRIC power distribution grids - Abstract
Metro stray currents flowing into neutral-point-grounded transformers can cause serious direct current (DC) bias. Affected by both metro train and urban power grid operations, transformer neutral-point DC caused by metro stray current is complex, dynamic, and time-varying, which changes the DC bias risk level of transformers. Thus, just installing blocking devices (BDs) at transformer neutral points with high instantaneous DC may make it difficult to comprehensively mitigate DC bias and lead to increased BD installation. To solve this, through optimizing BD installation placements, a mitigation method for transformer DC bias is proposed. In the proposed method, the DC bias risk level and BD installation number are included in the constraint and objective functions. To evaluate the risk level of transformer DC bias, four indicators are proposed considering the distribution characteristics of neutral DC. To optimize the BD installation placements, the effects of both the metro train dynamic operation and the operation topology of the urban power grid on neutral DCs are considered. The Monte Carlo method is used to sample the train operation conditions and a relation matrix among transformers is established. Applying the method to a certain power system, the result of BD installation placements shows that the transformers supplying the metro system must have BDs installed at their neutral points. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Hybrid Steel-Polyethylene Fiber-Reinforced Iron Ore Tailing Concrete: Mechanical, Sulfate Freeze–Thaw Resistance, and Microscopic Characteristics.
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Wang, Jing and Li, Xiaopeng
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IRON ores ,SULFATES ,CONCRETE ,FREEZE-thaw cycles ,DAMAGE models ,POROSITY - Abstract
This study examines the effects of iron ore tailing (IOT) replacement ratios and the hybridization of steel fiber (SF) and polyethylene (PE) fiber (PF) on the mechanical, sulfate freeze–thaw (F–T) resistance, and microscopic characteristics of IOT concrete. The mechanical properties of specimens including compressive strength (f
cu ) and splitting tensile strength (fsts ) were evaluated. Sulfate F–T cycle indices of specimens including surface damage, fcu loss, relative dynamic elastic modulus (RDEM), and mass loss are examined. Meanwhile, microscopic characteristics are analyzed using industrial computer technology (CT) and scanning electron microscopy (SEM). Results indicated that IOT replacement ratios below 40% positively influenced mechanical properties and sulfate F–T resistance, whereas ratios exceeding 40% exhibited adverse effects. Incorporating hybrid SF and PF further enhanced the mechanical properties and sulfate F–T resistance of IOT concrete. The IOT concrete containing 1.5% SF and 0.6% PF (designated T40S1.5P0.6) demonstrates significantly improved mechanical properties and sulfate F–T resistance. A set of parameters was proposed to predict the fsts . The Weibull damage model, capable of quantitatively reflecting the F–T damage of IOT concrete, was established. The pore structure of IOT concrete gradually deteriorates with increasing sulfate F–T cycles. The pore characteristics of T40S1.5P0.6 were superior. This was further validated through SEM observations. [ABSTRACT FROM AUTHOR]- Published
- 2024
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12. Mitophagy Regulates the Circadian Rhythms by Degrading NR1D1 in Simulated Microgravity and Isolation Environments.
- Author
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Zhou, Sihai, Li, Xiaopeng, Liang, Fengji, Ji, Guohua, Lv, Ke, Yuan, Yanhong, Zhao, Yujie, Yan, Na, Zhang, Chuanjie, Cai, Shiou, Zhang, Shuhui, Liu, Xu, Song, Bo, and Qu, Lina
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CIRCADIAN rhythms , *REDUCED gravity environments , *SUPRACHIASMATIC nucleus , *BODY temperature , *HEART beat , *ANIMAL disease models , *SPACE flight - Abstract
Long-term spaceflight is known to induce disruptions in circadian rhythms, which are driven by a central pacemaker located in the suprachiasmatic nucleus (SCN) of the hypothalamus, but the underlying molecular mechanisms remain unclear. Here, we developed a rat model that simulated microgravity and isolation environments through tail suspension and isolation (TSI). We found that the TSI environment imposed circadian disruptions to the core body temperature, heart rate, and locomotor-activity rhythms of rats, especially in the amplitude of these rhythms. In TSI model rats' SCNs, the core circadian gene NR1D1 showed higher protein but not mRNA levels along with decreased BMAL1 levels, which indicated that NR1D1 could be regulated through post-translational regulation. The autophagosome marker LC3 could directly bind to NR1D1 via the LC3-interacting region (LIR) motifs and induce the degradation of NR1D1 in a mitophagy-dependent manner. Defects in mitophagy led to the reversal of NR1D1 degradation, thereby suppressing the expression of BMAL1. Mitophagy deficiency and subsequent mitochondrial dysfunction were observed in the SCN of TSI models. Urolithin A (UA), a mitophagy activator, demonstrated an ability to enhance the amplitude of core body temperature, heart rate, and locomotor-activity rhythms by prompting mitophagy induction to degrade NR1D1. Cumulatively, our results demonstrate that mitophagy exerts circadian control by regulating NR1D1 degradation, revealing mitophagy as a potential target for long-term spaceflight as well as diseases with SCN circadian disruption. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Changes in the Range of Four Advantageous Grasshopper Habitats in the Hexi Corridor under Future Climate Conditions.
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Li, Donghong, Gan, Huilin, Li, Xiaopeng, Zhou, Huili, Zhang, Hang, Liu, Yaomeng, Dong, Rui, Hua, Limin, and Hu, Guixin
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CORRIDORS (Ecology) ,GRASSHOPPERS ,RECEIVER operating characteristic curves ,CURRENT distribution ,GRASSLANDS - Abstract
Simple Summary: Grasshoppers are the most widely distributed pests in the natural grasslands of the Hexi Corridor in Gansu, northwest China. We clarified the distribution of the grasshopper suitable areas and the main environmental variables affecting the distribution of the grasshopper suitable areas, which will provide a basis for monitoring and forecasting grasshoppers in grassland. Therefore, based on the MaxEnt model, this study predicted the distribution of the four grasshoppers in their suitable areas by combining five environmental variables, namely climate, vegetation, soil, topography, and human footprint, and analyzed the main influencing factors affecting the distribution of the suitable areas. Mean annual precipitation was the main environmental variable affecting the distribution of grasshopper habitats, and the extent of the habitat of four species of grasshoppers either increased or decreased in future. Angaracris rhodopa (Fischer et Walheim), Calliptamus abbreviatus (Ikonnikov), Myrmeleotettix palpalis (Zubowsky), and Oedaleus decorus asiaticus (Bey-Bienko) are the main grasshoppers that harm the natural grassland in the Hexi Corridor in Gansu, northwest China. In this study, the MaxEnt model was employed to identify the key environmental factors affecting the distribution of the four grasshoppers' habitats and to assess their distribution under current and future climate conditions. The aim was to provide a basis for grasshopper monitoring, prediction, and precise control. In this study, distribution of suitable habitats for A. rhodopa, C. abbreviates, M. palpalis, O. decorus asiaticus were predicted under current and future climatic scenarios using the Maxent model. The average AUC (area under the ROC curve) and TSS (true skill statistic) values of the four grasshoppers were greater than 0.9, and the simulation results were excellent and highly reliable. The mean annual precipitation was the main factor limiting the current range of suitable areas for these four species. Under the current climate, A. rhodopa, C. abbreviatus, and O. decorus asiaticus were mainly distributed in the central and eastern parts of the Hexi Corridor, and M. palpalis was distributed throughout the Hexi Corridor, with a suitable area of 1.29 × 10
4 , 1.43 × 104 , 1.44 × 104 , and 2.12 × 104 km2 , accounting for 13.7%, 15.2%, 15.3%, and 22.5% of the total area of the grasslands in the Hexi Corridor, respectively. The highly suitable areas of A. rhodopa, C. abbreviatus, and O. decorus asiaticus were mainly distributed in the eastern-central part of Zhangye City, the western part of Wuwei City, and the western and southern parts of Jinchang City, with areas of 0.20 × 104 , 0.29 × 104 , and 0.35 × 104 km2 , accounting for 2.2%, 3%, and 3.7% of the grassland area, respectively. The high habitat of M. palpalis was mainly distributed in the southeast of Jiuquan City, the west, middle, and east of Zhangye City, the west of Wuwei City, and the west and south of Jinchang City, with an area of 0.32 × 104 km2 , accounting for 3.4% of the grassland area. In the 2030s, the range of A. rhodopa, C. abbreviatus, and O. decorus asiaticus was predicted to increase; the range of M. palpalis will decrease. The results of this study could provide a theoretical basis for the precise monitoring and control of key areas of grasshoppers in the Hexi Corridor. [ABSTRACT FROM AUTHOR]- Published
- 2024
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14. A New Technique for Urban and Rural Settlement Boundary Extraction Based on Spectral–Topographic–Radar Polarization Features and Its Application in Xining, China.
- Author
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Li, Xiaopeng, Zhou, Guangsheng, Zhou, Li, Lv, Xiaomin, Li, Xiaoyang, He, Xiaohui, and Tian, Zhihui
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RANDOM forest algorithms , *EXTRACTION techniques , *URBAN planning , *LANDSAT satellites , *CLIMATE change , *CARRAGEENANS - Abstract
Highly accurate data on urban and rural settlement (URS) are essential for urban planning and decision-making in response to climate and environmental changes. This study developed an optimal random forest classification model for URSs based on spectral–topographic–radar polarization features using Landsat 8, NASA DEM, and Sentinel-1 SAR as the remote-sensing data sources. An optimal urban and rural settlement boundary (URSB) extraction technique based on morphological and pixel-level statistical methods was established to link discontinuous URSs and improve the accuracy of URSB extraction. An optimal random forest classification model for URSs was developed, as well as a technique to optimize URSB, using the Google Earth Engine (GEE) platform. The URSB of Xining, China, in 2020 was then extracted at a spatial resolution of 30 m, achieving an overall accuracy and Kappa coefficient of 96.21% and 0.92, respectively. Compared to using a single spectral feature, these corresponding metrics improved by 16.21% and 0.35, respectively. This research also demonstrated that the newly constructed Blue Roof Index (BRI), with enhanced blue roof features, is highly indicative of URSs and that the URSB was best extracted when the window size of the structural elements was 13 × 13. These results can be used to provide technical support for obtaining highly accurate information on URSs. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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15. Gene Therapy for Genetic Syndromes: Understanding the Current State to Guide Future Care.
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Henderson, Marian L., Zieba, Jacob K., Li, Xiaopeng, Campbell, Daniel B., Williams, Michael R., Vogt, Daniel L., Bupp, Caleb P., Edgerly, Yvonne M., Rajasekaran, Surender, Hartog, Nicholas L., Prokop, Jeremy W., and Krueger, Jena M.
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GENE therapy ,SPINAL muscular atrophy ,DUCHENNE muscular dystrophy ,COST benefit analysis ,RETINAL degeneration - Abstract
Gene therapy holds promise as a life-changing option for individuals with genetic variants that give rise to disease. FDA-approved gene therapies for Spinal Muscular Atrophy (SMA), cerebral adrenoleukodystrophy, β-Thalassemia, hemophilia A/B, retinal dystrophy, and Duchenne Muscular Dystrophy have generated buzz around the ability to change the course of genetic syndromes. However, this excitement risks over-expansion into areas of genetic disease that may not fit the current state of gene therapy. While in situ (targeted to an area) and ex vivo (removal of cells, delivery, and administration of cells) approaches show promise, they have a limited target ability. Broader in vivo gene therapy trials have shown various continued challenges, including immune response, use of immune suppressants correlating to secondary infections, unknown outcomes of overexpression, and challenges in driving tissue-specific corrections. Viral delivery systems can be associated with adverse outcomes such as hepatotoxicity and lethality if uncontrolled. In some cases, these risks are far outweighed by the potentially lethal syndromes for which these systems are being developed. Therefore, it is critical to evaluate the field of genetic diseases to perform cost–benefit analyses for gene therapy. In this work, we present the current state while setting forth tools and resources to guide informed directions to avoid foreseeable issues in gene therapy that could prevent the field from continued success. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. A Backup Protection Based on Compensated Voltage for Transmission Lines Connected to Wind Power Plants.
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Wang, Hao, Li, Xiaopeng, Dong, Xinzhou, and Jiang, Xiaofeng
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WIND power plants ,ELECTRIC lines ,WIND power ,VOLTAGE ,SHORT circuits - Abstract
Due to the influence of complex control, the short circuit current provided by wind power generation units will exhibit new characteristics, such as limited amplitude and controlled phase, affecting the performance of traditional protections. This paper analyzes the work principle and defects of one kind of multiphase compensated distance protection. Drawing on the idea of fault identification by multiphase compensated distance protection, novel pilot protection using the compensated voltage on both sides is proposed. The proposed method has a strong anti-fault resistance ability. The test results indicate that the proposed method can distinguish the internal faults and external faults reliably, unaffected by the new characteristics of short circuit current. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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17. ERS-HDRI: Event-Based Remote Sensing HDR Imaging.
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Li, Xiaopeng, Cheng, Shuaibo, Zeng, Zhaoyuan, Zhao, Chen, and Fan, Cien
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REMOTE sensing , *HIGH dynamic range imaging , *IMAGING systems , *IMAGE fusion , *IMAGE segmentation , *REMOTE-sensing images - Abstract
High dynamic range imaging (HDRI) is an essential task in remote sensing, enhancing low dynamic range (LDR) remote sensing images and benefiting downstream tasks, such as object detection and image segmentation. However, conventional frame-based HDRI methods may encounter challenges in real-world scenarios due to the limited information inherent in a single image captured by conventional cameras. In this paper, an event-based remote sensing HDR imaging framework is proposed to address this problem, denoted as ERS-HDRI, which reconstructs the remote sensing HDR image from a single-exposure LDR image and its concurrent event streams. The proposed ERS-HDRI leverages a coarse-to-fine framework, incorporating the event-based dynamic range enhancement (E-DRE) network and the gradient-enhanced HDR reconstruction (G-HDRR) network. Specifically, to efficiently achieve dynamic range fusion from different domains, the E-DRE network is designed to extract the dynamic range features from LDR frames and events and perform intra- and cross-attention operations to adaptively fuse multi-modal data. A denoise network and a dense feature fusion network are then employed for the generation of the coarse, clean HDR image. Then, the G-HDRR network, with its gradient enhancement module and multiscale fusion module, performs structure enforcement on the coarse HDR image and generates a fine informative HDR image. In addition, this work introduces a specialized hybrid imaging system and a novel, real-world event-based remote sensing HDRI dataset that contains aligned remote sensing LDR images, remote sensing HDR images, and concurrent event streams for evaluation. Comprehensive experiments have demonstrated the effectiveness of the proposed method. Specifically, it improves state-of-the-art PSNR by about 30% and the SSIM score by about 9% on the real-world dataset. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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- View/download PDF
18. Process Parameter Optimization for CO 2 Laser Polishing of Fused Silica Using the Taguchi Method.
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Lu, Guanghua, Li, Xiaopeng, Wang, Dasen, and Wang, Kehong
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FUSED silica , *TAGUCHI methods , *CARBON dioxide , *LASER beams , *LASERS , *SILICA fibers - Abstract
Fused silica was polished to a high quality by a CO2 laser beam with a rapid scanning rate. The rapid scanning rate produced a line laser heat source, resulting in a "polishing line" during the polishing process. The Taguchi method was used to evaluate the comprehensive influence of polishing process parameters on the polishing qualities. Four factors, namely the length of laser reciprocating scanning (A), laser beam scanning speed (B), feed speed (C), and defocusing amount (D), were investigated in this study. The optimal process parameter combination (A1B1C1D1) was obtained. The surface roughness of fused silica was reduced from Ra = 0.157 μm to 0.005 μm. Through analysis of variance (ANOVA), it was found that laser beam scanning speed (B) had a significant influence on the polishing quality. The interaction of the two factors plays a decisive role in the determination of the best process parameters, and the influence of other multi-factor interaction can be ignored; the interaction between A × B is the largest, with a contribution of 42.69%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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19. Finite-Time Robust Flight Control of Logistic Unmanned Aerial Vehicles Using a Time-Delay Estimation Technique.
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Ma, Jinyu, Yu, Shengdong, Hu, Wenke, Wu, Hongyuan, Li, Xiaopeng, Zheng, Yilong, Zhang, Junhui, and Chen, Puhui
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- 2024
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20. Influence of Thermal Annealing on Mechanical and Optical Property of SiO 2 Film Produced by ALD.
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Zhi, Xintao, Li, Xiaopeng, Yuan, Songmei, Wang, Dasen, and Wang, Kehong
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OPTICAL properties , *FUSED silica , *TRANSMISSION electron microscopy , *LASER damage , *RAMAN spectroscopy - Abstract
The application range of fused silica optical components can be expanded and the cost of fused silica components can be reduced by depositing the same material film on fused silica substrate. However, due to the different manufacturing process, the performance of ALD SiO2 film is lower than that of fused silica substrate, which also limits the use of this process. In this paper, ALD SiO2 film with different thicknesses were deposited, and then the structure and properties were tested. Finally, the ALD SiO2 film was treated via the annealing process. Transmission electron microscopy (TEM) showed that the ALD SiO2 film had good compactness and substrate adhesion. The Raman spectra showed that the ALD SiO2 film and substrate had the same structure, with only slight differences. The XRD pattern showed that ALD-fused silica did not crystallize before or after annealing. The infrared spectra showed that there was an obvious Si-OH defect in the ALD SiO2 film. The laser damage showed that the ALD SiO2 film had a much lower damage threshold than the fused silica substrate. The nanoindentation showed that the mechanical properties of the ALD SiO2 film were much lower than those of the fused silica substrate. After a low-temperature annealing treatment, the ALD SiO2 film Si-OH defect was reduced, the ALD SiO2 film four-member ring content was increased, the elastic modulus of the ALD SiO2 film was increased from 45.025 GPa to 68.025 GPa, the hardness was increased from 5.240 GPa to 9.528 GPa, and the ALD SiO2 film damage threshold was decreased from 5.5 J/cm2 to 1.3 J/cm2. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
21. Urban Parks Quality Assessment Using Multi-Dimension Indicators in Chengdu, China.
- Author
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Zhang, Sining, Song, Haoxiang, Li, Xiaopeng, and Luo, Shixian
- Subjects
URBAN parks ,LANDSCAPE design ,LANDSCAPE architecture ,ENVIRONMENTAL justice ,ARCHITECTURAL design ,URBANIZATION ,SOCIAL indicators - Abstract
High-quality urban parks are considered an integral part of health resources as they can deliver diverse ecosystem services. However, the quality of parks is not always similar, resulting in different levels and values of the services provided. A systematic and complete assessment frame of urban park quality is limited. From the perspective of landscape architecture and design, this study aims to propose a comprehensive assessment framework of urban park quality based on six dimensions (planning and design, cultural services, complete and various facilities, landscape planting, landscape management, and landscape ecology), consisting of 27 indicators with different weights by using the objective and subjective weighting method. Taking the city of Chengdu, China as a case study, 100 urban parks are studied via field investigation and scored using methods that consist of a category count, existence score, field measurement, experts score, and photo review and recheck (13,589 images). The results reveal the spatial distribution and differences in park quality, including six quality dimensions and five districts, and the proportion of the existing quality elements in 100 parks. Based on the results, the spatial areas (Barren area, Low-quality area, Medium-quality area, and High-quality area) are identified, which leads to the establishment of the improvement strategies of spatial equity regarding multi-quality parks. The results can help improve the assessment index system of urban parks, guide the landscape planning and design of urban parks for sustainability, as well as provide a reference for future environmental and social equity development, so as to provide insight and reference for decision-makers and designers considering the landscape planning and design of parks. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
22. A Multi-Terminal Control Method for AC Grids Based on a Hybrid High-Voltage Direct Current with Cascaded MMC Converters.
- Author
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Liu, Lei, Li, Xiaopeng, Jiang, Qin, Teng, Yufei, Chen, Mingju, Wang, Yongfei, Zeng, Xueyang, Luo, Yiping, and Pan, Pengyu
- Subjects
ROBUST control ,ELECTRIC power distribution grids ,VOLTAGE control ,IDEAL sources (Electric circuits) ,SECURE Sockets Layer (Computer network protocol) ,HIGH voltages ,OSCILLATIONS ,AC DC transformers - Abstract
The hybrid high-voltage direct current (HVDC) transmission system with cascaded MMC converters has become a promising alternative for possessing the technical merits of both line-commuted converter (LCC) and voltage source converter (VSC), resulting in favorable characteristics and potential control of good prospect. This paper pays heightened attention to the feasible power and DC voltage control modes of a hybrid HVDC system; characteristics of master–slave control show higher flexibility than the LCC-VSC HVDC system, which demonstrates that the exceptional potential can serve to stability support the AC power grids. To optimize the control effect, besides damping level to attenuate power oscillations, the robustness suitable for various faults is also considered to obtain a multi-objective control problem. A detailed solution is proceeding using the TLS-ESPRIT identification algorithm and H
2 /H∞ hybrid robust control theory. This motivates multi-terminal controllers in the LCC rectifier and MMC inverters, which immensely improve the stability of both sending and receiving girds at the same time. According to the parameters of the actual hybrid HVDC project, the simulation model is established in PSCAD v4.6.2 software, and proposed control methods have been verified to satisfy damping objectives and perform well in multiple operating scenarios. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
23. A New Method for Bare Permafrost Extraction on the Tibetan Plateau by Integrating Machine Learning and Multi-Source Information.
- Author
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Li, Xiaoyang, Ji, Yuhe, Zhou, Guangsheng, Zhou, Li, Li, Xiaopeng, He, Xiaohui, and Tian, Zhihui
- Subjects
PERMAFROST ,MACHINE learning ,ALPINE regions ,RANDOM forest algorithms ,REMOTE sensing ,LAND cover ,TUNDRAS - Abstract
Bare permafrost refers to permafrost with almost no vegetation on the surface, which is an essential part of the ecosystem of the Tibetan Plateau. An accurate extraction of the boundaries of bare permafrost is vital for studying how it is being impacted by climate change. The accuracy of permafrost and bare land distribution maps is inadequate, and the spatial and temporal resolution is low. This is due to the challenges associated with obtaining significant amounts of data in high-altitude and alpine regions and the limitations of current mapping techniques in effectively integrating multiple factors. This study introduces a novel approach to extracting information about the distribution of bare permafrost. The approach introduced here involves amalgamating a sample extraction method, the fusion of multi-source remote sensing information, and a hierarchical classification strategy. Initially, the available multi-source permafrost data, expert knowledge, and refinement rules for training samples are integrated to produce extensive and consistent permafrost training samples. Using the random forest method, these samples are then utilized to create features and classify permafrost. Subsequently, a methodology utilizing a hierarchical classification approach in conjunction with machine learning techniques is implemented to identify an appropriate threshold for fractional vegetation cover, thereby facilitating the extraction of bare land. The bare permafrost boundary is ultimately derived through layer overlay analysis. The permafrost classification exhibits an overall accuracy of 90.79% and a Kappa coefficient of 0.806. The overall accuracies of the two stratified extractions in bare land were 97.47% and 96.99%, with Kappa coefficients of 0.954 and 0.911. The proposed approach exhibits superiority over the extant bare land and permafrost distribution maps. It is well-suited for retrieving vast bare permafrost regions and is valuable for acquiring bare permafrost distribution data across a vast expanse. It offers technical assistance in acquiring extended-term data on the distribution of exposed permafrost on the Tibetan Plateau. Furthermore, it facilitates the elucidation of the impact of climate change on exposed permafrost. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
24. Comparison of the Effects of Recombinant and Native Prolactin on the Proliferation and Apoptosis of Goose Granulosa Cells.
- Author
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Deng, Donghang, Li, Wen, Li, Xiaopeng, Yuan, Xin, Li, Liang, Wang, Jiwen, Han, Chunchun, and Hu, Shenqiang
- Subjects
GRANULOSA cells ,GEESE ,OVARIAN follicle ,IMMUNOAFFINITY chromatography ,PROLACTIN ,APOPTOSIS - Abstract
In poultry, prolactin (PRL) plays a key role in the regulation of incubation behavior, hormone secretion, and reproductive activities. However, previous in vitro studies have focused on the actions of PRL in ovarian follicles of poultry, relying on the use of exogenous or recombinant PRL, and the true role of PRL in regulating ovarian granulosa cell (GC) functions in poultry awaits a further investigation using endogenous native PRL. Therefore, in this study, we first isolated and purified recombinant goose PRL protein (rPRL) and native goose PRL protein (nPRL) using Ni-affinity chromatography and rabbit anti-rPRL antibodies-filled immunoaffinity chromatography, respectively. Then, we analyzed and compared the effects of rPRL and nPRL at different concentrations (0, 3, 30, or 300 ng/mL) on the proliferation and apoptosis of both GCs isolated from goose ovarian pre-hierarchical follicles (phGCs) and from hierarchical follicles (hGCs). Our results show that rPRL at lower concentrations increased the viability and proliferation of both phGCs and hGCs, while it exerted anti-apoptotic effects in phGCs by upregulating the expression of Bcl-2. On the other hand, nPRL increased the apoptosis of phGCs in a concentration-dependent manner by upregulating the expressions of caspase-3 and Fas and downregulating the expressions of Bcl-2 and Becn-1. In conclusion, this study not only obtained a highly pure nPRL for the first time, but also suggested a dual role of PRL in regulating the proliferation and apoptosis of goose GCs, depending on its concentration and the stage of follicle development. The data presented here can be helpful in purifying native proteins of poultry and enabling a better understanding of the roles of PRL during the ovarian follicle development in poultry. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
25. Boosted Chemical Protective Properties Using Interface Constructed between Ti 3 C 2 T x MXene and Natural Rubber.
- Author
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Chen, Qinyu, Zhang, Min, Li, Xiaopeng, Zhou, Chuan, Yang, Guang, Li, Heguo, and Zheng, Xiaohui
- Subjects
CHEMICAL properties ,RUBBER ,VULCANIZATION ,TENSILE strength ,POISONS ,PROTECTIVE clothing - Abstract
Rubbers are extensively applied in chemical protective clothing (CPC) due to their eye-catching anti-penetration of chemicals. However, their impermeability, particularly that of natural rubber (NR), is unsatisfactory. In this work, we demonstrate the facile construction of Ti
3 C2 Tx MXene/NR interface using a plant-scale and feasible method combining latex mixing, emulsion flocculation, and flat-plate vulcanisation. The above crafts achieved a homogeneous dispersion of Ti3 C2 Tx MXene in the NR matrix in a single layer, thereby constructing a strong interfacial interaction between Ti3 C2 Tx MXene and NR, which induced the formation of a robust three-dimensional (3D) network in the composite. The anti-swelling capacity of the 3D cross-linked network structure and the layered structure of Ti3 C2 Tx MXene effectively prolonged the permeation path of toxic chemicals. Compared with pure NR, the nanocomposite with 1 wt% of Ti3 C2 Tx MXene showed substantially enhanced breakthrough times of toluene, dichloromethane, and concentrated sulfuric acid (increased by 140%, 178.6%, and 92.5%, respectively). Furthermore, its tensile strength, elongation at break, and shore hardness increased by 7.847 MPa, 194%, and 12 HA, respectively. Taken together with the satisfactory anti-permeability, tensile strength, elongation at break, and shore hardness, the resulting Ti3 C2 Tx MXene/NR nanocomposites hold promise for application to long-term and high-strength CPC in the chemical industry and military fields. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
26. Differential Transcriptomic Signatures of Small Airway Cell Cultures Derived from IPF and COVID-19-Induced Exacerbation of Interstitial Lung Disease.
- Author
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Uhl, Katie, Paithankar, Shreya, Leshchiner, Dmitry, Jager, Tara E., Abdelgied, Mohamed, Dixit, Bhavna, Marashdeh, Raya, Luo-Li, Dewen, Tripp, Kaylie, Peraino, Angela M., Tamae Kakazu, Maximiliano, Lawson, Cameron, Chesla, Dave W., Luo-Li, Ningzhi, Murphy, Edward T., Prokop, Jeremy, Chen, Bin, Girgis, Reda E., and Li, Xiaopeng
- Subjects
INTERSTITIAL lung diseases ,LUNGS ,CELL culture ,IDIOPATHIC pulmonary fibrosis ,COVID-19 pandemic ,TRANSCRIPTOMES ,COVID-19 - Abstract
Idiopathic pulmonary fibrosis (IPF) is a pathological condition wherein lung injury precipitates the deposition of scar tissue, ultimately leading to a decline in pulmonary function. Existing research indicates a notable exacerbation in the clinical prognosis of IPF patients following infection with COVID-19. This investigation employed bulk RNA-sequencing methodologies to describe the transcriptomic profiles of small airway cell cultures derived from IPF and post-COVID fibrosis patients. Differential gene expression analysis unveiled heightened activation of pathways associated with microtubule assembly and interferon signaling in IPF cell cultures. Conversely, post-COVID fibrosis cell cultures exhibited distinctive characteristics, including the upregulation of pathways linked to extracellular matrix remodeling, immune system response, and TGF-β1 signaling. Notably, BMP signaling levels were elevated in cell cultures derived from IPF patients compared to non-IPF control and post-COVID fibrosis samples. These findings underscore the molecular distinctions between IPF and post-COVID fibrosis, particularly in the context of signaling pathways associated with each condition. A better understanding of the underlying molecular mechanisms holds the promise of identifying potential therapeutic targets for future interventions in these diseases. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
27. Structural and Mechanical Properties of Doped Tobermorite.
- Author
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Li, Xiaopeng, Zhang, Hongping, Zhan, Haifei, and Tang, Youhong
- Subjects
- *
CALCIUM silicate hydrate , *YOUNG'S modulus , *STRUCTURAL design , *CEMENT clinkers , *CALCIUM silicates , *ALKALINE earth metals , *PORTLAND cement - Abstract
As calcium silicate hydrate (C-S-H) is the main binding phase in concrete, understanding the doping behavior of impurity elements in it is important for optimizing the structure of cementitious materials. However, most of the current studies focus on cement clinker, and the doping mechanism of impurity elements in hydrated calcium silicate is not yet fully understood. The hydrated calcium silicate component is complex, and its structure is very similar to that of the tobermorite mineral family. In this study, the effects of three different dopants (Mg, Sr and Ba) on a representing structure of C-S-H—tobermorite—was systematically explored using densify functional theory (DFT) calculations. The calculations show that Mg doping leads to a decrease in lattice volume and causes obvious structure and coordination changes of magnesium–oxygen polyhedra. This may be the reason why high formation energy is required for the Mg-doped tobermorite. Meanwhile, doping only increases the volume of the Sr- and Ba-centered oxygen polyhedra. Specifically, the Mg-doped structure exhibits higher chemical stability and shorter interatomic bonding. In addition, although Mg doping distorts the structure, the stronger chemical bonding between Mg-O atoms also improves the compressive (~1.99% on average) and shear resistance (~2.74% on average) of tobermorillonite according to the elastic modulus and has less effect on the anisotropy of the Young's modulus. Our results suggest that Mg doping is a promising strategy for the optimized structural design of C-S-H. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
28. Power Equalization Control Strategy for MMCs in Hybrid-Cascaded UHVDC System.
- Author
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Liu, Lei, Teng, Yufei, Li, Xiaopeng, Tang, Yong, and Jiang, Xiaofeng
- Subjects
ELECTRIC current rectifiers ,LOGIC design ,HYBRID systems ,TOPOLOGY - Abstract
Based on the hybrid-cascaded topology of ultra-high-voltage direct current (UHVDC) engineering, this study clarified the mechanism of unbalanced power generation among modular multilevel converters (MMCs) at the inverter side following the fault of the AC system at the rectifying side, and then proposed the power equalization strategy for MMCs. By performing closed-loop control on the active power deviation between constant-voltage and constant-power MMCs, it was possible to achieve automatic power equalization among MMCs after the occurrence of a fault so as to avoid the detrimental effect of a single MMC's power fluctuation on the connected AC system. Meanwhile, the control enabling logic was designed to ensure the reliable input and stable exit of the control strategy throughout the disturbance period. Finally, a PSCAD/EMTDC platform was used to simulate various types of faults in the AC system at the rectifier side in order to validate the effectiveness of the proposed power equalization strategy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
29. An Improved UAV-Based ATI Method Incorporating Solar Radiation for Farm-Scale Bare Soil Moisture Measurement.
- Author
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Jia, Renhao, Liu, Jianli, Zhang, Jiabao, Niu, Yujie, Jiang, Yifei, Xuan, Kefan, Wang, Can, Ji, Jingchun, Ma, Bin, and Li, Xiaopeng
- Subjects
SOIL moisture measurement ,SOLAR radiation ,MOISTURE measurement ,FLEXIBLE work arrangements ,REMOTE sensing ,WEATHER ,SOIL moisture - Abstract
The use of UAV-based remote sensing for soil moisture has developed rapidly in recent decades, with advantages such as high spatial resolution, flexible work arrangement, and ease of operation. In bare and low-vegetation-covered soils, the apparent thermal inertia (ATI) method, which adopts thermal infrared data from UAV-based remote sensing, has been widely used for soil moisture estimation at the field scale. However, the ATI method may not perform well under inconsistent weather conditions due to inconsistency of the intensity of the soil surface energy input. In this study, an improvement of the ATI method (ATI-R), considering the variation in soil surface energy input, was developed by the incorporation of solar radiation measurements. The performances of the two methods were compared using field experiment data during multiple heating processes under various weather conditions. It showed that on consistently sunny days, both ATI-R and ATI methods obtained good correlations with the volumetric water contents (VWC) (R
2 ATI-R = 0.775, RMSEATI-R = 0.023 cm3 ·cm−3 and R2 ATI = 0.778, RMSEATI = 0.018 cm3 ·cm−3 ) on cloudy or a combination of sunny and cloudy days as long as there were significant soil-heating processes despite the different energy input intensities; the ATI-R method could perform better than the ATI method (cloudy: R2 ATI-R = 0.565, RMSEATI-R = 0.024 cm3 ·cm−3 and R2 ATI = 0.156, RMSEATI = 0.033 cm3 ·cm−3 ; combined: R2 ATI-R = 0.673, RMSEATI-R = 0.028 cm3 ·cm−3 and R2 ATI = 0.310, RMSEATI = 0.032 cm3 ·cm−3 ); and on overcast days, both the ATI-R and ATI methods could not perform satisfactorily (R2 ATI-R = 0.027, RMSEATI-R = 0.024 cm3 ·cm−3 and R2 ATI = 0.027, RMSEATI = 0.031 cm3 ·cm−3 ). The results indicate that supplemental solar radiation data could effectively expand applications of the ATI method, especially for inconsistent weather conditions. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
30. VLDNet: An Ultra-Lightweight Crop Disease Identification Network.
- Author
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Li, Xiaopeng, Zhang, Yichi, Peng, Yuhan, and Li, Shuqin
- Subjects
FEATURE extraction ,DEEP learning - Abstract
Existing deep learning methods usually adopt deeper and wider network structures to achieve better performance. However, we found that this rule does not apply well to crop disease identification tasks, which inspired us to rethink the design paradigm of disease identification models. Crop diseases belong to fine-grained features and lack obvious patterns. Deeper and wider network structures will cause information loss of features, which will damage identification efficiency. Based on this, this paper designs a very lightweight disease identification network called VLDNet. The basic module VLDBlock of VLDNet extracts intrinsic features through 1 × 1 convolution, and uses cheap linear operations to supplement redundant features to improve feature extraction efficiency. In inference, reparameterization technology is used to further reduce the model size and improve inference speed. VLDNet achieves state-of-the-art model (SOTA) latency-accuracy trade-offs on self-built and public datasets, such as equivalent performance to Swin-Tiny with a parameter size of 0.097 MB and 0.04 G floating point operations (FLOPs), while reducing parameter size and FLOPs by 297 times and 111 times, respectively. In actual testing, VLDNet can recognize 221 images per second, which is far superior to similar accuracy models. This work is expected to further promote the application of deep learning-based crop disease identification methods in practical production. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
31. Role of Reductive Soil Disinfestation and Chemical Soil Fumigation on the Fusarium Wilt of Dioscorea batatas Decne Suppression.
- Author
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Shao, Qin, Li, Xiaopeng, Zhao, Tian, Wu, Yiyang, Xiang, Liqin, Pan, Shengfu, Guo, Zihan, and Liu, Liangliang
- Abstract
Reductive soil disinfestation (RSD) and chemical soil fumigation (CSF) comprise the most popular pre-planting soil management strategies. Their efficiency in suppressing several plant diseases in agricultural production systems has been compared. However, the disease-control effect of these methods on Fusarium wilt disease in Dioscorea batatas Decne (D. batatas) remains unclear. Importantly, dissimilarities in the impact of their bio-predictors on plant health have not been well characterized. Herein, four treatments, including no treatment (CK), RSD with gran chaff (GC-RSD) and molasses (MO-RSD), and CSF with dazomet (DA-CSF), were performed in a pot experiment using D. batatas-diseased soil. Compared with the CK treatment, the Fusarium oxysporum population significantly decreased by 88.89–97.78% following the DA-CSF, GC-RSD, and MO-RSD treatments. The bacterial community and functional composition of the soil were considerably altered by these treatments. However, the incidence of Fusarium wilt disease in D. batatas was significantly decreased in the two RSD-treated soils, rather than in DA-CSF-treated soils. Bacterial α-diversity and population as well as some key nitrogen-related functional gene expressions as bio-predictors were significantly lower in DA-CSF-treated soil than in RSD-treated soil. In particular, the core (e.g., Azotobacter, Phenylobacterium, Clostridium, Bradyrhizobium, Microvirga, and Caulobacter) and unique (e.g., Pseudomonas, Brevundimonas, Flavobacterium, Ochrobactrum, and Sphingobacterium) functional microbiomes in RSD-treated soil exerted a positive impact on soil functional composition of the soil and plant growth. Taken together, our results indicate that RSD outperformed CSF in promoting plant health by regulating the bacterial community and functional composition. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
32. Research on IPFC-Based Dynamic Droop Control Strategy.
- Author
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Ding, Chaofan, Li, Xiaopeng, Li, Baohong, Jiang, Qin, Wen, Menghao, and Liu, Tianqi
- Subjects
- *
ELECTRIC lines , *ELECTRICAL load , *FREQUENCY stability - Abstract
The interline power flow controller (IPFC) presents a promising solution for managing the directional and quantitative interaction of power between different lines, facilitating a significant improvement in power system stability. Based on such a background, this paper proposes a dynamic droop control strategy to improve frequency stability through the use of IPFC equipment. To enhance the active power support ability of the IPFC, additional frequency control for the IPFC's active power control loop is designed with droop control, where each IPFC's power flow control limitations are also considered to make sure the original power of each line is controllable. Besides the addition of such basic control, the proposed droop strategy is designed in a dynamic style. The droop coefficients of each IPFC can be varied according to each line's power transmission margin, such that the power fluctuations can be shared more reasonably based on such a dynamic droop coordination strategy. The proposed methods are verified through PSCAD simulations. The results show that the dynamic droop control cannot only suppress the frequency disturbance, but also make power dispatch more efficient. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
33. Early Brain Injury and Neuroprotective Treatment after Aneurysmal Subarachnoid Hemorrhage: A Literature Review.
- Author
-
Li, Xiaopeng, Zeng, Lang, Lu, Xuanzhen, Chen, Kun, Yu, Maling, Wang, Baofeng, and Zhao, Min
- Subjects
- *
BRAIN injuries , *SUBARACHNOID hemorrhage , *LITERATURE reviews , *CEREBRAL vasospasm , *CEREBRAL ischemia , *CALCIUM channels - Abstract
Early brain injury (EBI) subsequent to subarachnoid hemorrhage (SAH) is strongly associated with delayed cerebral ischemia and poor patient prognosis. Based on investigations into the molecular mechanisms underlying EBI, neurovascular dysfunction resulting from SAH can be attributed to a range of pathological processes, such as microvascular alterations in brain tissue, ionic imbalances, blood–brain barrier disruption, immune–inflammatory responses, oxidative stress, and activation of cell death pathways. Research progress presents a variety of promising therapeutic approaches for the preservation of neurological function following SAH, including calcium channel antagonists, endothelin-1 receptor blockers, antiplatelet agents, anti-inflammatory agents, and anti-oxidative stress agents. EBI can be mitigated following SAH through neuroprotective measures. To enhance our comprehension of the relevant molecular pathways involved in brain injury, including brain ischemia–hypoxic injury, neuroimmune inflammation activation, and the activation of various cell-signaling pathways, following SAH, it is essential to investigate the evolution of these multifaceted pathophysiological processes. Facilitating neural repair following a brain injury is critical for improving patient survival rates and quality of life. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
34. A Review of Artificial Intelligence in the Rupture Risk Assessment of Intracranial Aneurysms: Applications and Challenges.
- Author
-
Li, Xiaopeng, Zeng, Lang, Lu, Xuanzhen, Chen, Kun, Yu, Maling, Wang, Baofeng, and Zhao, Min
- Subjects
- *
INTRACRANIAL aneurysms , *ARTIFICIAL intelligence , *RISK assessment , *ANEURYSMS , *MACHINE learning , *THERAPEUTIC embolization - Abstract
Intracranial aneurysms (IAs) are highly prevalent in the population, and their rupture poses a significant risk of death or disability. However, the treatment of aneurysms, whether through interventional embolization or craniotomy clipping surgery, is not always safe and carries a certain proportion of morbidity and mortality. Therefore, early detection and prompt intervention of IAs with a high risk of rupture is of notable clinical significance. Moreover, accurately predicting aneurysms that are likely to remain stable can help avoid the risks and costs of over-intervention, which also has considerable social significance. Recent advances in artificial intelligence (AI) technology offer promising strategies to assist clinical trials. This review will discuss the state-of-the-art AI applications for assessing the rupture risk of IAs, with a focus on achievements, challenges, and potential opportunities. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Bond Behavior of Plain Bars in Concrete under Reversed Cyclic Loading.
- Author
-
Zhao, Jun, Yin, Lu, Li, Xiaopeng, and Yue, Xinjie
- Subjects
CYCLIC loads ,CONCRETE fatigue ,STRESS-strain curves ,CONCRETE ,REINFORCING bars ,REINFORCED concrete buildings ,PLAINS - Abstract
Plain bars with a diameter of 10 mm are widely used in reinforced concrete buildings, and the bond behavior between the bars and concrete has an essential effect on the seismic performance of concrete structures. Thus, to assess the safety of old buildings and repaired buildings with normal concrete, it was necessary to further investigate the bond performance of the plain bars in the concrete. The bonding tests under monotonic and reversed cyclic loading were carried out on the specimens reinforced with plain bars, and the influences of concrete grade and embedment length on the bond behavior were taken into consideration. The results indicate the maximum bond stress under reversed cyclic loading is less than that under monotonic loading, and this is the same for corresponding slip for the same test parameters. The concrete compressive strength positively affects the maximum bond stress, whereas the embedment length has a negative effect. Based on the elasticity analysis and test data fitting, the expressions of bond stress at characteristic points on the bond stress–slip curves were carried out. Consequently, the bond stress–slip model was established, which could be applied to calculate the bond stress–slip relationships under monotonic and reversed cyclic loading. By comparison between the test curves and proposed model, a good agreement is observed, which indicates that the proposed model can be used to predict the bond stress–slip curve of plain bars in concrete. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
36. SheepFaceNet: A Speed–Accuracy Balanced Model for Sheep Face Recognition.
- Author
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Li, Xiaopeng, Zhang, Yichi, and Li, Shuqin
- Subjects
- *
HUMAN facial recognition software , *DEEP learning , *FACE perception , *SHEEP , *CONVOLUTIONAL neural networks , *COMPUTER vision , *FEATURE extraction - Abstract
Simple Summary: The use of computer vision technology has improved the effectiveness of individual sheep identification, but existing methods face challenges such as large parameter sizes, slow recognition speeds, and difficult deployment. To address this issue, we have made improvements and optimizations based on the Retinaface face recognition model to create a balanced speed-accuracy sheep face recognition model. The optimized model has fewer parameters, simpler computations, faster inference speeds, and higher recognition accuracy, making it well-suited for deployment on resource-constrained edge devices. This research is expected to promote the application of deep learning-based sheep face recognition methods in production. The recognition of sheep faces based on computer vision has improved the efficiency and effectiveness of individual sheep identification, providing technical support for the development of smart farming. However, current recognition models have problems such as large parameter sizes, slow recognition speed, and difficult deployment. Therefore, this paper proposes an efficient and fast basic module called Eblock and uses it to build a lightweight sheep face recognition model called SheepFaceNet, which achieves the best balance between speed and accuracy. SheepFaceNet includes two modules: SheepFaceNetDet for detection and SheepFaceNetRec for recognition. SheepFaceNetDet uses Eblock to construct the backbone network to enhance feature extraction capability and efficiency, designs a bidirectional FPN layer (BiFPN) to enhance geometric location ability, and optimizes the network structure, which affects inference speed, to achieve fast and accurate sheep face detection. SheepFaceNetRec uses Eblock to construct the feature extraction network, uses ECA channel attention to improve the effectiveness of feature extraction, and uses multi-scale feature fusion to achieve fast and accurate sheep face recognition. On our self-built sheep face dataset, SheepFaceNet recognized 387 sheep face images per second with an accuracy rate of 97.75%, achieving an advanced balance between speed and accuracy. This research is expected to further promote the application of deep-learning-based sheep face recognition methods in production. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
37. A New Model for Human Running Micro-Doppler FMCW Radar Features.
- Author
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Zhang, Yongqiang, Li, Xiaopeng, Ma, Guilei, Ma, Jinlong, Man, Menghua, and Liu, Shanghe
- Subjects
RADAR targets ,RADAR ,TIME-frequency analysis ,RIGID bodies ,HUMAN body ,MOTION capture (Human mechanics) ,HUMAN mechanics - Abstract
Human body detection is very important in the research of automotive safety technology. The extraction and analysis of human micro-motion based on frequency-modulated continuous wave (FMCW) radar is gradually receiving attention. Aimed at the modulation effect of human micro-motion on FMCW radar, a human running model is proposed to study human radar characteristics. According to the scattering characteristics of rigid bodies, the analytical expression of human running radar echoes is established. By using time–frequency analysis, the micro-Doppler features in the radar echoes are extracted during the running period. Under running conditions, the micro-Doppler characteristics of key components are studied. This model is applied to the real FMCW radar verification platform, and the runners are measured at a distance of 10 m. The fit rate of all parts of the human body can reach above 90%. The overall fit rate of the human model can reach up to 90.6%. The model proposed is a realistic and simple human kinematic model. This model, which can realize the real simulation of a running human body and provide strong support for human target radar echo analysis, can fill the deficiency of FMCW radar technology in the complex motion model. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
38. The Effect of Fiber Volume Fraction on Fiber Distribution in Steel Fiber Reinforced Self-Compacting Concrete.
- Author
-
Zhao, Yun, Bi, Jihong, Zhou, Junlong, Liu, Xiaomin, Li, Xiaopeng, and Geng, Wenbin
- Subjects
FIBER-reinforced concrete ,FRACTIONS ,SELF-consolidating concrete ,FIBER orientation ,FIBERS ,RHEOLOGY ,STEEL - Abstract
This paper investigates the effect of fiber volume fraction on fiber distribution in steel fiber reinforced self-compacting concrete (SFRSCC) through experiments and numerical simulations. Three types of SFRSCC beam specimens with different fiber volume fractions (0.3%, 0.6%, and 0.9%) were cut to expose the steel fibers. The number and the orientation angle of the steel fibers on the beam sections were determined by image analysis techniques. Fiber density, fiber segregation coefficient, fiber dispersion coefficient and fiber orientation coefficient were applied to evaluate fiber distribution on the beam sections. Based on the experimental data, numerical models simulating the pouring process of fresh SFRSCC were established to analyze the overall fiber distribution in the specimens. The results show that the distribution state of the fibers on the beam sections is not random and uniform, which is correlated to the fiber volume fraction. Due to the variable rheological properties, a greater fiber volume fraction causes better fiber uniformity, lower fiber segregation and worse fiber alignment on the beam sections. Meanwhile, the numerical results show that the distribution law of fibers along the length direction of the specimens is almost independent of the fiber volume fraction. In addition, increasing the fiber volume fraction results in the increase of the average angle of the fiber orientation in the specimens. The results can provide a reference for optimizing the fiber distribution in the concrete matrix. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
39. Investigating the Potential of Cosmic-Ray Neutron Sensing for Estimating Soil Water Content in Farmland and Mountainous Areas.
- Author
-
Jiang, Yifei, Xuan, Kefan, Gao, Chen, Liu, Yiren, Zhao, Yuan, Deng, Haodong, Li, Xiaopeng, and Liu, Jianli
- Subjects
SOIL moisture ,NEUTRONS ,STANDARD deviations ,COSMIC rays - Abstract
The conventional methods of estimating soil water content (SWC) are mainly based on in situ measurements at sampling points and remote sensing measurements over an entire region. In view of these methods, cosmic-ray neutron sensing (CRNS) has received increasing attention in recent years as a mesoscale, noncontact SWC estimation technology that can provide more accurate and timely estimates of SWC over a larger area. In this study, we estimated SWC using both CRNS and soil-mounted detectors in farmland and mountainous areas, and evaluated the accuracy of the estimations at two experimental sites. Ultra-rapid adaptable neutron-only simulation (URANOS) was used to simulate the detection radius and depth of the two experimental sites and to obtain the spatial weights of the CRNS footprint. The results show that the theoretical range of detection was reduced in farmland compared to mountainous areas during the experimental period, suggesting that farmland retained more SWC even with less precipitation. Spatial weights were simulated to calculate the SWC of sampling points, and the weighted and averaged SWC were then correlated with CRNS. The weighting calculation improves the accuracy of CRNS estimations, with a determination coefficient (R
2 ) of 0.645 and a root mean square error (RMSE) of 0.046 cm3 ·cm−3 for farmland, and reproduces the daily dynamics of SWC. The R2 and RMSE in mountainous areas are 0.773 and 0.049 cm3 ·cm−3 , respectively, and the estimation accuracy of CRNS cannot be improved by the weighting calculation. The estimation accuracy of CRNS is acceptable in both regions, but the mountainous terrain obstructs neutron transmission, causing a deviation between the actual and theoretical neutron footprints in mountainous areas. Thus, the accuracy of SWC estimation is limited in mountainous terrain. In conclusion, this study demonstrates that CRNS is suitable for use in farmland and mountainous areas and that further attention should be given to the effects of topography and vegetation when it is applied in mountainous environments. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
40. A Novel Drug with Potential to Treat Hyperbilirubinemia and Prevent Liver Damage Induced by Hyperbilirubinemia: Carbon Dots Derived from Platycodon grandiflorum.
- Author
-
Chen, Rui, Ma, Huagen, Li, Xiaopeng, Wang, Meijun, Yang, Yunbo, Wu, Tong, Zhang, Yue, Kong, Hui, Qu, Huihua, and Zhao, Yan
- Subjects
HYPERBILIRUBINEMIA ,X-ray photoelectron spectroscopy ,HIGH performance liquid chromatography ,TRANSMISSION electron microscopy ,CHINESE medicine - Abstract
Platycodon grandiflorum (PG) is a traditional Chinese medicine with a long history, but its active compounds have not been reported. In this study, novel carbon dots (CDs), PG-based CDs (PGC-CDs), were discovered and prepared from PG via calcinations and characterized by transmission electron microscopy; high-resolution transmission electron microscopy; X-ray diffraction, fluorescence, ultraviolet-visible, and Fourier-transform infrared spectrometers; X-ray photoelectron spectroscopy; and high-performance liquid chromatography. In addition, the safety and antioxidant activity of PGC-CDs was evaluated by RAW264.7 cells and LO2 cells. The therapeutic effects of PGC-CDs on hyperbilirubinemia and liver protection were evaluated in a bilirubin-induced hyperbilirubinemia mice model. The experiment confirmed that the diameter range of PGC-CDs was from 1.2 to 3.6 nm. PGC-CDs had no toxicity to RAW264.7 cells and LO2 cells at a concentration of 3.91 to 1000 µg/mL and could reduce the oxidative damage of cells caused by H
2 O2 . PGC-CDs could inhibit the increase levels of bilirubin and inflammation factors and increase the levels of antioxidants and survival rate, demonstrating that PGC-CDs possessed anti-inflammatory and anti-oxidation activity. PGC-CDs may reduce the content of bilirubin, so as to reduce a series of pathological lesions caused by bilirubin, which has potential in treating hyperbilirubinemia and preventing liver damage induced by hyperbilirubinemia. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
41. Study of Dynamic Performance and Control Strategy of Variable Stiffness Actuator System Based on Two-Inertial-System.
- Author
-
Yang, Zemin, Li, Xiaopeng, Xu, Jinchi, Chen, Renzhen, and Yang, Hexu
- Subjects
- *
SLIDING mode control , *ACTUATORS , *DYNAMICAL systems , *COMPLEX variables , *ENERGY consumption , *FRICTION - Abstract
The study of position control for variable stiffness actuators is important for improving their energy efficiency and robustness. In this paper, for the previously proposed nonlinear variable stiffness actuator, firstly, a dynamic model of the variable stiffness actuator system is established based on a two-inertia-system theory. Secondly, the effects of friction and gravity factors on the dynamic performance of the system are analyzed. The results of the study show that friction and gravity have obvious effects on the dynamic characteristics of the system in the constant stiffness state, and that these effects are more complex and obvious in the variable stiffness state, which proves the reasonableness and necessity of considering friction and gravity in the dynamics modeling process. Then, in order to improve the dynamic performance of the system and make its positioning performance meet the requirements, the control strategy of the variable stiffness actuator system is studied. The results show that the sliding mode control strategy based on nonlinear disturbance observer and dynamics model is a good solution to the effect of friction and gravity on the system, and can make its position-tracking performance meet the requirements. Finally, the correctness and effectiveness of the control strategy are verified experimentally. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
42. Non-Toxic and Flexible Radiation-Shielding Composites Based on Natural Rubber Containing Elemental W Fillers for Efficient Shielding against X/γ-rays.
- Author
-
Chen, Zhai, Li, Xiaopeng, Lu, Lin, Yuan, Bo, Wang, Liying, Li, Zhen, and Li, Heguo
- Subjects
ATTENUATION coefficients ,RUBBER ,ATOMIC number ,LEAD - Abstract
Conventional radiation-shielding composites usually contain lead, which results in high toxicity and poor portability. Tungsten (W) is an ideal radiation-shielding element that can replace lead due to its high atomic number and non-toxicity. In this work, radiation-shielding composites were prepared using natural rubber (NR) as a matrix and three different particle size powders, namely W, WO
3 and WC, as fillers. The results show that, for X-rays, the linear attenuation coefficient of radiation-shielding composites based on natural rubber containing WC with a particle size of 50 μm (50 WC/NR) is 27.005 cm−1 at an X-ray tube voltage of 40 kV, which is more than 14 times the linear attenuation coefficient of NR. For γ-rays, a linear attenuation coefficient of 50 WC/NR achieves 8.320 cm−1 at 81 keV, which is over 55 times the linear attenuation coefficient of NR. In addition, 50 WC/NR had the highest elongation at break at 548.989% and had the lowest hardness at 62 HA. In summary, 50 WC/NR can be used as an alternative to traditional radiation-shielding materials containing lead and has wide application prospects. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
43. The Sense of Cooperation on Interdependent Networks Inspired by Influence-Based Self-Organization.
- Author
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Li, Xiaopeng, Wang, Zhonglin, Liu, Jiuqiang, and Yu, Guihai
- Subjects
- *
PRISONER'S dilemma game , *COOPERATION - Abstract
Influence, as an inherently special attribute, is bound to profoundly affect a player's behavior. Meanwhile, a growing body of studies suggests that interactions among networks may be more important than isolated ones. Thus, we try our best to research whether such a setup can stimulate the sense of cooperation in spatial prisoner's dilemma games through the co-evolution of strategy imitation and interdependence networks structures. To be specific, once a player's influence exceeds the critical threshold τ , they will be permitted to build a connection with the corresponding partner on another network in a self-organized way, thus gaining additional payoff. However, a player's influence changes dynamically with the spread of strategy, resulting in time-varying connections between networks. Our results show that influence-based self-organization can facilitate cooperation, even under quite poor conditions, where cooperation cannot flourish in a single network. Furthermore, there is an optimal threshold τ to optimize the evolution of cooperation. Through microcosmic statistical analysis, we are surprised to find that the spontaneous emergence of connections between interdependence networks, especially those between cooperators, plays a key role in alleviating social dilemmas. Finally, we uncover that if the corresponding links between interdependence networks are adjusted to random ones, the evolution of cooperation will be blocked, but it is still better than relying on simple spatial reciprocity on an isolated lattice. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
44. Effects of Organic Amendments on Soil Pore Structure under Waterlogging Stress.
- Author
-
Xuan, Kefan, Li, Xiaopeng, Zhang, Jiabao, Jiang, Yifei, Ma, Bin, and Liu, Jianli
- Subjects
- *
SOIL amendments , *SOIL structure , *POROSITY , *PORE size distribution , *WATERLOGGING (Soils) , *CATTLE manure - Abstract
Organic amendments are a proven method of reducing soil erosion. However, the effect of organic additives on the pore properties of soils waterlogged by extreme rainfall has been minimally investigated. In this study, we collected rainfall data, established a field experiment consisting of randomized groups, and imaged the pore structure of waterlogged soil treated with different organic amendments (9 t ha−1 of maize straw [MS], 2.37 t ha−1 of cattle manure [OF], a mixture of 9 t ha−1 of MS and 1.89 t ha−1 of cattle manure [SOF], 7.4 t ha−1 of biochar [BC], 8.1 t ha−1 of woody peat [WP], and 3 L ha−1 of polyacrylamide [PAM]) in three-dimensions by X-ray microtomography and digital image analysis, which further quantified the effects. The results showed that, compared with the control, BC increased the total porosity by 54.28% and the connected porosity by 119.75%, but did not affect the pore shape and size distribution. BC and SOF improved the soil connectivity indexes; e.g., their C/I ratios increased by 177.44% and 149.62%, and the coordination numbers increased by 6.75% and 15.76%, respectively. MS had fewer, but longer and larger, channels and throats. Extreme precipitation events were significantly negatively correlated with all connectivity indicators. This study shows that organic materials can optimize the pore structure of waterlogged soil, with BC being the most resistant to erosion. However, extreme precipitation events can counteract the benefits organic additives have on soil pore structure. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Mutual Effects of Zinc Concentration and Ratio of Red-Blue Light on Growth and Nutritional Quality of Flowering Chinese Cabbage Sprouts.
- Author
-
Li, Xiaopeng, Liu, Kaizhe, He, Xinyang, Chen, Yongkang, Tan, Jiehui, Jiang, Haozhao, He, Rui, Li, Yamin, and Liu, Houcheng
- Subjects
CHINESE cabbage ,SPROUTS ,PLANT polyphenols ,GERMINATION ,PHOTOSYNTHETIC pigments ,PRINCIPAL components analysis - Abstract
The nutritional quality and biomass of various sprouts can be enhanced by Zn and red-blue light, especially the Brassica sprouts. However, the combined effects of this two on sprouts are rarely reported. In this study, different Zn concentrations (0, 1.74, 3.48, 10.43 and 17.39 mM) were combined with two ratios of red-blue light-emitting diodes (LEDs) (R: B = 1:2, 1R2B; R: B = 2:1, 2R1B, at 70 μmol m
−2 s−1 PPFD, 14 h/10 h, light/dark) to investigate their mutual effects on the growth, mineral elements, and nutritional quality in flowering Chinese cabbage sprouts (FCCS). Fresh weight, dry weight, contents of organic Zn, soluble sugar, vitamin C, total flavonoids, total polyphenol, FRAP (ferric ion-reducing antioxidant power) and DPPH (radical inhibition percentage of 1,1-diphenyl-2-picrylhydrazyl) were significantly increased by Zn supplement (10.43 and 17.39 mM) and 2R1B, while hypocotyl length and moisture content were decreased remarkably by Zn supplement. Total glucosinolates contents in the sprouts increased dramatically under 2R1B compared with 1R2B, while photosynthetic pigments contents decreased. Heat map and principal component analysis showed that 2R1B + 17.39 mM Zn was the optimal treatment for the accumulation of biomass and health-promoting compound in FCCS, suggesting that a suitable combination of light quality and Zn supplement might be beneficial to zinc-biofortified FCCS production. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
46. Urban Expansion Was the Main Driving Force for the Decline in Ecosystem Services in Hainan Island during 1980–2015.
- Author
-
Geng, Jia, Yuan, Mingsheng, Xu, Shen, Bai, Tingting, Xiao, Yang, Li, Xiaopeng, and Xu, Dong
- Published
- 2022
- Full Text
- View/download PDF
47. Effect of Chloride and Iodide on the Corrosion Behavior of 13Cr Stainless Steel.
- Author
-
Liu, Wanying, Yang, Hong, Li, Xiaopeng, Zhang, Zhi, Lin, Yuanhua, and Deng, Kuanhai
- Subjects
STAINLESS steel ,SCANNING electrochemical microscopy ,CHLORIDES ,METALLIC oxides ,ALUMINUM oxide ,IODIDES ,AUSTENITIC stainless steel - Abstract
The corrosion behavior and mechanism of 13Cr stainless steel in the solution with 1 mol/L NaCl and 5 mmol/L KI were investigated by weight loss method, scanning electrochemical microscopy (SECM), the phase analysis (XRD) of inclusions, and surface analysis technique (SEM and EDS). Results showed that the corrosion rate was a linear relationship with the time and Cl
− concentration. The corrosion became serious with the increase in time and Cl− concentration. The corrosion occurred in the unstable electroactive points that contained aluminum oxide and metallic phase inclusions. The generation and disappearance of the electroactive points simultaneously occurred with the corrosion. The active dissolved level on different areas of the surface of 13Cr stainless-steel sample was different. The oxidation current peak of the sample presented the strip shape. The corrosion dissolution was mainly caused by aluminum oxide inclusions (Al2 O3 ) and FeAl phase. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
48. Distribution Pattern and Factors Influencing Spontaneous Plant Diversity in Different Wetland Habitats.
- Author
-
Yang, Yifan, Xu, Bin, Yu, Qingqing, Fan, Likun, Guo, Tingting, Fu, Dongshi, Chen, Hao, Yan, Hai, Shao, Feng, and Li, Xiaopeng
- Subjects
HABITATS ,ANIMAL dispersal ,WETLANDS ,PLANT habitats ,WETLAND plants ,PLANT diversity ,TYPHA - Abstract
Wetlands contain a large number of spontaneous plants, and the ecological value of such plants should not be underestimated. However, the influence of the surrounding environment on the composition of spontaneous plants in wetlands is still unclear. Hangzhou Jiangyangfan Ecological Park, built more than 20 years ago, is the first ecological park in China based on the "wild state" concept. The wetland in the park was taken as a study case, and we investigated some of the ecological factors affecting the diversity and distribution pattern of spontaneous plants in wetland habitats after natural succession. A total of 100 species of spontaneous plants were recorded, belonging to 93 genera and 48 families, with native species accounting for approximately 78% of the total. We found significant differences in the species diversity and distribution patterns of spontaneous plants in different habitats and microhabitats. According to the biological characteristics of spontaneous plants, the fruit types were mostly achenes and capsules, and the seed dispersal mode was mainly animal dispersal. Different fruit types and dispersal modes affected the composition and distribution of spontaneous plants. In terms of environmental factors, the water depth and slope aspect were the key factors determining the diversity and distribution pattern of spontaneous plants. It was also found that the clustering degree of cultivated plants had an effect on the composition of spontaneous plants. To form a more natural wetland landscape, it is necessary to provide a variety of growing environments for spontaneous plants. We suggest allocating appropriate habitat types in wetlands and reducing human intervention to increase biodiversity. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
49. BES1/BZR1 Family Transcription Factors Regulate Plant Development via Brassinosteroid-Dependent and Independent Pathways.
- Author
-
Shi, Hongyong, Li, Xiaopeng, Lv, Minghui, and Li, Jia
- Subjects
- *
TRANSCRIPTION factors , *PLANT development - Abstract
The BES1/BZR1 family is a plant-specific small group of transcription factors possessing a non-canonical bHLH domain. Genetic and biochemical analyses within the last two decades have demonstrated that members of this family are key transcription factors in regulating the expression of brassinosteroid (BR) response genes. Several recent genetic and evolutionary studies, however, have clearly indicated that the BES1/BZR1 family transcription factors also function in regulating several aspects of plant development via BR-independent pathways, suggesting they are not BR specific. In this review, we summarize our current understanding of this family of transcription factors, the mechanisms regulating their activities, DNA binding motifs, and target genes. We selectively discuss a number of their biological functions via BR-dependent and particularly independent pathways, which were recently revealed by loss-of-function genetic analyses. We also highlight a few possible future directions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
50. Ti/Cu/Kovar Multilayer Interlayer PTLP Diffusion Bonding Si 3 N 4 /Ht250.
- Author
-
Zhang, Deku, Zhang, Lian, Zhou, Ning, Wang, Kehong, and Li, Xiaopeng
- Subjects
DIFFUSION bonding (Metals) ,MULTILAYERS ,MICROSTRUCTURE ,CAST-iron testing ,SHEAR strength - Abstract
In this paper, partial transient liquid phase (PTLP) diffusion bonding between Si
3 N4 ceramics and Ht250 cast iron was carried out by using an Ti/Cu/Kovar/Cu/Ti interlayer. The effects of the heating temperature and holding time on the microstructure, formation mechanism, and mechanical properties of Si3 N4 /Ht250 cast iron joints were studied. The results show that the maximum shear strength of the joint is 112 MPa when the welding temperature is 1000 °C and the holding time is 1 h. In addition, the problems of Ti/Cu/Ti intermetallic compound formation and Cu/Si3 N4 ceramic residual thermal stress in the joint can be effectively alleviated. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
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