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In order to investigate the effect of ultrasound on the structure and physical stability of chicken myofibrillar protein (MP) under low-salt conditions (0.15 mol/L NaCl), as well as the oxidizing effect of free radicals generated by ultrasound on MP, this study investigated the changes in the structure and oxidative properties of MP under low-salt conditions after ultrasound treatments (20 kHz, 450 W for 0, 3, 6, 9, and 12 min). The results showed that compared with the control group, the solubility, physical stability, and absolute ζ-potential of MP under low-salt conditions increased significantly (P < 0.05) with ultrasonic treatment time, whereas the turbidity and particle size decreased significantly (P < 0.05). The solubility was increased to 58.5% after 12 min of ultrasonic treatment. After ultrasonic treatment, the surface hydrophobicity and molecular flexibility were significantly increased, indicating that ultrasonic treatment caused the highly aggregated structure of myofibrillar protein to unfold and the internal hydrophobic groups to be exposed under low-salt conditions. After ultrasonic treatment for more than 6 min, the free sulfhydryl content of MP began to gradually decrease, whereas the content of disulfide bonds increased. After ultrasonic treatment for 12 min, the contents of free radicals, carbonyl groups and dimerized tyrosine (by 20.55%) were significantly increased (P < 0.05), while the free amino group content was decreased significantly (P < 0.05). In conclusion, ultrasonic treatment changed the structural properties of MP under low-salt conditions and increased its physical stability, thereby contributing to the formation of emulsions. Ultrasonic treatment can generate free radicals; ultrasonic treatment time for 6 min can exacerbate the oxidation of MP. So, attention should be paid to the oxidizing effect of free radicals generated by ultrasound on MP when applying ultrasonic treatment to improve the functional properties of MP.

The deflecting to airflow flap of civil aircraft are generally driven by complex multi-hinge mechanisms in space. According to the requirements of the airworthiness clause CCAR25.671, it is necessary to carry out research on the mechanism characteristics under typical faults. Firstly, a digital prototype of the mechanism motion is constructed, and the hinge point of the rigid multi-hinge mechanism is associated with the flexible flap body by using the RBE2 unit, and the rigid-flexible coupling dynamic model of the flap mechanism is established. Then, under three aerodynamic load conditions of cruise, take-off and landing, two typical faults, hinge jamming and one-side failure of control system, are simulated by adjusting the hinge friction coefficient and setting one-side driving failure. Finally, the variation law of driving torque and hinge point load is analyzed. The results show that:when the hinge is stuck, the inner drive link ear piece is stretched and damaged; when the inner drive fails, the radial load at the hinge point of the outer rocker arm increases significantly. In practice, we should focus on the middle joint of the outer rocker arm of this type of flap. The radial and axial load-bearing capacity of the bearing avoids the situation of separate manipulation of the outer mechanism, and at the same time, it is necessary to increase the torque protection for the entire drive system.

Objective To explore the clinical significance of serum C-type lectin domain 1（CTLD1） for prognosis of patients with idiopathic membranous nephropathy（IMN）. Methods A total of 116 patients with IMN diagnosed in Shengjing Hospital from September 2016 to December 2019 were selected as the case group, and healthy volunteers with age and gender matching in the physical examination center during the same period were selected as the health control group. Clinical data of patients in case group were collected and followed up for ≥ 2 years to record treatment and outcome. The expression level of PLAZR antigen and CTLD1 antigen epitope were detected by ELISA. The differences of clinical indexes between CTLD1 positive group and negative group were compared, and the prognostic influencing factors of IMN patients were analyzed. b>Results There was a statistical difference in CTLD1 expression level between health control group and case group（P

Emulsions prepared using myofibrillar protein (MP) as an emulsifier have poor stability under low NaCl condition. The effect of high-intensity ultrasound (HIU) treatment (frequency of 20 kHz, and power of 450 W) for different periods of time (0, 3, 6, 9, and 12 min) on the emulsifying properties of chicken MP under low NaCl condition (0.15 mol/L NaCl) and the stability and rheological properties of MP emulsions were investigated. The results showed that compared with the control group, the emulsifying activity index (EAI) and emulsion stability index (ESI) of MP significantly increased with increasing ultrasonic treatment time (P < 0.05). The Turbiscan stability index (TSI) and particle size of MP emulsions decreased significantly with increasing ultrasonication time, and the absolute value of the zeta potential significantly increased (P < 0.05). The rheological analysis showed that ultrasound treatment significantly improved the viscoelasticity of MP emulsions. The oil-water interfacial tension analysis showed that ultrasound treatment effectively enhanced the mobility of MP, and rapidly decreased the interfacial tension. Meanwhile, ultrasound treatment significantly increased the amount of adsorbed protein in MP emulsions (P < 0.05), indicating that ultrasound treated MP contributed to emulsion stability. As observed by cold-field scanning electron microscopy, the emulsion prepared with MP treated by ultrasound for 12 min had the smallest droplet size. In conclusion, ultrasound treatment can significantly improve the emulsion stability of MP under low NaCl condition, which provides a theoretical reference for the application of ultrasound treatment to reduced-salt emulsified meat products.