31 research outputs found

    High Efficiency Secondary Somatic Embryogenesis in Hovenia dulcis

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    Embryogenic callus was obtained from mature seed explants on medium supplemented with 2,4-dichlorophenoxyacetic acid. Primary somatic embryos (SEs) can only develop into abnormal plants. Well-developed SEs could be obtained through secondary somatic embryogenesis both in solid and liquid cultures. Temperature strongly affected induction frequency of secondary embryogenesis. Relatively high temperature (30∘C) and germinated SEs explants were effective for induction of secondary somatic embryos, and low temperature (20∘C) was more suitable for further embryo development, plantlet conversion, and transplant survival. Somatic embryos formed on agar medium had larger cotyledons than those of embryos formed in liquid medium. Supplementing 0.1 mg L−1 6-benzyladenine (BA) was effective for plant conversion; the rate of plant conversion was 43.3% in somatic embryos from solid culture and 36.5% in embryos from liquid culture. In vitro plants were successfully acclimatized in the greenhouse. The protocol established in this study will be helpful for large-scale vegetative propagation of this medicinal tree

    Study on Tribological Properties and Mechanisms of Different Morphology WS2 as Lubricant Additives

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    In the present work, the relationship curve of the coefficient of friction (COF) with varying loads of different morphology WS2 lubricating additives in the friction process at various sliding speeds was studied. On this basis, wear marks and elements on the wear surfaces after friction were analyzed, and then the anti-wear and mechanism effects of WS2 of different forms in the lubrication process were discussed. Meanwhile, the Stribeck curve was used to study the lubrication state of the lubricating oil in the friction process. It was revealed that the COF of lubricating oil containing lamellar WS2 decreased by 29.35% at optimum condition and the minimum COF was concentrated at around 100 N. The COF of lubricating oil containing spherical WS2 decreased by 30.24% and the minimum coefficient was concentrated at 120 N. The extreme pressure property of spherical WS2 was better than that of lamellar WS2, and the wear resistance of spherical WS2 was more stable when the load was over 80 N. The different morphology of WS2 additives can play anti-wear and anti-friction roles within a wide range of sliding speeds

    Power Losses Estimation Platform For Power Converters

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    A power losses analysis platform integrating powerful analysis software Pspiceâ„¢, MathCADâ„¢ and Maxwellâ„¢ capable of calculating losses on the key components in converters is presented. The operational block diagram and the analysis principle, as well as the technical issue, are discussed. One analysis example is given and the prototype is built. The validity of the analysis is verified by the experimental results

    Time-Series Field Phenotyping of Soybean Growth Analysis by Combining Multimodal Deep Learning and Dynamic Modeling

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    The rate of soybean canopy establishment largely determines photoperiodic sensitivity, subsequently influencing yield potential. However, assessing the rate of soybean canopy development in large-scale field breeding trials is both laborious and time-consuming. High-throughput phenotyping methods based on unmanned aerial vehicle (UAV) systems can be used to monitor and quantitatively describe the development of soybean canopies for different genotypes. In this study, high-resolution and time-series raw data from field soybean populations were collected using UAVs. The RGB (red, green, and blue) and infrared images are used as inputs to construct the multimodal image segmentation model—the RGB & Infrared Feature Fusion Segmentation Network (RIFSeg-Net). Subsequently, the segment anything model was employed to extract complete individual leaves from the segmentation results obtained from RIFSeg-Net. These leaf aspect ratios facilitated the accurate categorization of soybean populations into 2 distinct varieties: oval leaf type variety and lanceolate leaf type variety. Finally, dynamic modeling was conducted to identify 5 phenotypic traits associated with the canopy development rate that differed substantially among the classified soybean varieties. The results showed that the developed multimodal image segmentation model RIFSeg-Net for extracting soybean canopy cover from UAV images outperformed traditional deep learning image segmentation networks (precision = 0.94, recall = 0.93, F1-score = 0.93). The proposed method has high practical value in the field of germplasm resource identification. This approach could lead to the use of a practical tool for further genotypic differentiation analysis and the selection of target genes

    Probucol ameliorates hepatic stellate cell activation and autophagy is associated with farnesoid X receptor

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    Probucol has antioxidant effects and inhibits inflammation. Farnesoid X receptor (FXR) is a nuclear receptor that regulates autophagy, which is regarded as the key cause of the activation of hepatic stellate cell (HSC). In this study, the effects of probucol on HSC activation and autophagy in vitro and vivo and the role of FXR in this progress were investigated. Results showed that probucol ameliorated hepatic fibrosis and autophagy, and increased the expression of FXR in liver in a mouse model of fibrosis induced by CCl4. And probucol could alleviate lipopolysaccharide-induced autophagy and HSC activation in vitro. In addition, probucol increased FXR expression, and the Z-guggulsterone, an antagonist of FXR, could block the effects of probucol on HSC activation and autophagy. Additionally, agonists of FXR could suppress LPS-induced autophagy and activation. These results suggest that probucol could ameliorate hepatic fibrosis, and inhibit HSC autophagy and activation, and these effects are associated with FXR. Keywords: Probucol, Hepatic fibrosis, Autophagy, Farnesoid X recepto

    Influence of Oxygen and Zirconium Contents on The Mechanical Properties of Ti-23Nb-0.7Ta-Zr-O Alloys

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    Ti-23Nb-0.7Ta-(0, 2)Zr-(1.2, 4, 6, 10)O alloys were prepared using a non-consumable arc-melting method. The tensile property of Ti-23Nb-0.7Ta-2Zr-1.2O alloys was tested at temperatures from −196 °C to 750 °C. The influence of O and Zr contents on thermal forgeability, room-temperature hardness and tensile property at 750 °C was investigated. For Ti-23Nb-0.7Ta-2Zr-1.2O alloy, the tensile strength decreased, and the ductility increased with the temperature increase. O and Zr had a negative effect on the thermal forgeability. Room-temperature hardness and tensile strength increased with an increase in O and Zr contents due to interstitial, solid solution strengthening and second-phase strengthening. All of the alloys exhibited high ductility at 750 °C with the total elongation above 34% and reductions in area above 80%
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