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Summary: The nuclear factor Y (NF‐Y) transcription factors play important roles in plant development and physiological responses. However, the relationship between NF‐Y, plant hormone and plant stress resistance in tropical crops remains unclear. In this study, we identified MeNF‐YC15 gene in the NF‐Y family that significantly responded to Xanthomonas axonopodis pv. manihotis (Xam) treatment. Using MeNF‐YC15‐silenced and ‐overexpressed cassava plants, we elucidated that MeNF‐YC15 positively regulated disease resistance to cassava bacterial blight (CBB). Notably, we illustrated MeNF‐YC15 downstream genes and revealed the direct genetic relationship between MeNF‐YC15 and 1‐aminocyclopropane‐1‐carboxylic acid (ACC) oxidase (MeACO1)‐ethylene module in disease resistance, as evidenced by the rescued disease susceptibility of MeNF‐YC15 silenced cassava plants with ethylene treatment or overexpressing MeACO1. In addition, the physical interaction between 2C‐type protein phosphatase 1 (MePP2C1) and MeNF‐YC15 inhibited the transcriptional activation of MeACO1 by MeNF‐YC15. In summary, MePP2C1‐MeNF‐YC15 interaction modulates ethylene biosynthesis and cassava disease resistance, providing gene network for cassava genetic improvement. [ABSTRACT FROM AUTHOR]

High-pressure pure waterjet (WJ) technology is widely used in the hole drilling process for carbon fiber–reinforced polymers (CFRP) laminates because of its high processing efficiency and zero heat affected zones. However, the phenomena of the delamination zone and poor roundness pose significant challenges to the hole processing of CFRP laminates. In this study, the numerical and experimental investigation of a high-pressure pure WJ CFRP laminate drilling process are conducted, to improve the quality of the pure WJ drilling process. A comprehensive coupled fluid–solid numerical model based on the smoothed particle hydrodynamics method is developed to simulate the pure WJ drilling process of CFRP laminates and determine mechanism of the material removal. Thereafter, extensive pure WJ drilling experiments are conducted on two stacking sequence CFRP laminates to obtain a hole with remarkable roundness. The simulation results illustrate that during the WJ drilling of CFRP laminates, the material removal process and damage zones of each inter-laminate interface are mainly extended along the fiber direction (the direction of longitudinal Young's modulus). Water-wedging action is observed to play an important role in the damage of inter-laminate interface and propagation of peel-up and push-down delamination. Furthermore, the experimental results show that an increase in the WJ pressure contributes to the reduced hole taper and surface roughness of sidewalls. Holes with diameters below 2 mm are successfully drilled, and a roundness error of 0.05 mm is obtained for the [0/45/–45/90]2s CFRP laminate, which is 1/6 of that of the [0]16 laminate. [ABSTRACT FROM AUTHOR]

Endometriosis (EMs) is a gynecological disorder. Ligustrazine has been reported to exert an anti-inflammatory effect on EMs. However, the underlying mechanisms are not completely understood. To investigate the effects of ligustrazine on the progression of EMs and the underlying regulatory mechanisms. Human endometrial stromal cells (HESCs) were isolated from patients with EMs or control subjects. HESCs were treated with 25, 50, 100, or 200 μM ligustrazine for 1, 3, 6, or 12 h. Western blot and enzyme-linked immunosorbent assays were performed to determine the levels of proteins and inflammatory cytokines, respectively. The binding between STAT3 and insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) was assessed by chromatin immunoprecipitation and dual-luciferase reporter assays. The relationship between IGF2BP1 and RELA was assessed by RNA immunoprecipitation and RNA pull-down assay. Phosphorylated STAT3, IGF2BP1, RELA, TNF-α, IL-6, and IL-1β were upregulated in EMs tissues compared with control tissues (by 1.79-, 2.55-, 1.58-, 3.01-, 2.55-, and 3.34-fold, respectively). Ligustrazine inhibited the expression of p-STAT3, IGF2BP1, RELA, IL-6, TNF-α, and IL-1β. Overexpression of STAT3 promoted RELA-mediated inflammatory responses, while ligustrazine (100 µM) notably reversed this phenomenon. Ligustrazine also alleviated RELA-induced inflammation via downregulating IGF2BP1. STAT3 bound to the promoter of IGF2BP1, and IGF2BP1 bound to the RELA mRNA. Ligustrazine inhibited inflammation in EMs via regulating the STAT3/IGF2BP1/RELA axis. These findings propose a new agent against EMs and support the development of ligustrazine-based treatment strategies for EMs. [ABSTRACT FROM AUTHOR]

The pure waterjet (WJ) drilling process of carbon-fiber-reinforced polymer (CFRP) laminates causes damage, such as tears and delamination, leading to poor-quality hole-wall. Ultrasonic-vibration-assisted technology can improve the quality of hole walls and repair such damage, particularly the delamination of CFRP laminates. In this study, we conducted a numerical and experimental investigation of a high-pressure pure WJ drilling process of CFRP laminates performed using ultrasonic vibration to improve the delamination phenomena of the pure WJ drilling process. An explicit dynamic model using the smoothed particle hydrodynamics method was employed to simulate the ultrasonic-vibration-assisted WJ drilling of CFRP laminates and ascertain the optimal drilling performance. Thereafter, WJ drilling experiments were conducted to verify the numerical simulation. The results illustrate that the employment of ultrasonic vibration significantly increased the material removal rate by approximately 20%. Moreover, the water-wedging action that induces the propagation of delamination was weakened with an increase in the amplitude of the ultrasonic vibration. The hole-wall quality was optimal with the following drilling parameters: amplitude, 10 μm; frequency, 20 kHz; and WJ velocity, 900 m/s. The delamination zone length was only 0.19 mm and was reduced by 85.6% compared with the values obtained using non-assisted WJ drilling. [ABSTRACT FROM AUTHOR]

Abrasive waterjet (AWJ) cutting technology has notable advantages such as high cutting efficiency and cost-effectiveness, particularly for machining difficult-to-process metal matrix composites such as SiCp/Al. However, the uncontrollable kerf shape, cutting depth, and surface quality render AWJ grooving on SiCp/Al substrate challenging. In this study, a novel method for grooving on SiCp/Al substrate using AWJ, with the aim of enhancing the quality of AWJ machining processes, is proposed. First, a predictive model based on the improved model of erosion by the impact of solid particle is established for the geometry of groove kerf profiles. Second, a comprehensive analysis is performed to investigate the influence of process parameters on the quality of grooves using the waterjet cutting mechanism, thereby identifying the optimal process parameters for achieving superior results. Finally, the proposed predictive model of the kerf depth is used to predict the groove depth in multi-pass waterjet cutting. The results reveal that the combination of machining parameters comprising 100 MPa, 500 mm/min, and two waterjet passes achieves a desirable kerf shape, lowest roughness value of 5.11 μm, and flattest bottom profile. Additionally, these parameters achieve a high material removal rate of up to 1326.17 mm3/min. The predicted depth results agree well with the five multi-pass experimental results, and the average difference between the predicted model and the experimental results is 5.24%. This study can provide crucial guidelines for the AWJ grooving process of SiCp/Al substrates. [ABSTRACT FROM AUTHOR]

The pure waterjet (WJ) drilling process of carbon-fiber-reinforced polymer (CFRP) laminates causes damage, such as tears and delamination, leading to poor-quality hole-wall. Ultrasonic-vibration-assisted technology can improve the quality of hole walls and repair such damage, particularly the delamination of CFRP laminates. In this study, we conducted a numerical and experimental investigation of a high-pressure pure WJ drilling process of CFRP laminates performed using ultrasonic vibration to improve the delamination phenomena of the pure WJ drilling process. An explicit dynamic model using the smoothed particle hydrodynamics method was employed to simulate the ultrasonic-vibration-assisted WJ drilling of CFRP laminates and ascertain the optimal drilling performance. Thereafter, WJ drilling experiments were conducted to verify the numerical simulation. The results illustrate that the employment of ultrasonic vibration significantly increased the material removal rate by approximately 20%. Moreover, the water-wedging action that induces the propagation of delamination was weakened with an increase in the amplitude of the ultrasonic vibration. The hole-wall quality was optimal with the following drilling parameters: amplitude, 10 μm; frequency, 20 kHz; and WJ velocity, 900 m/s. The delamination zone length was only 0.19 mm and was reduced by 85.6% compared with the values obtained using non-assisted WJ drilling.