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In this study, chitosan was used to enhance the photodynamic antibacterial effect of curcumin through ionic interactions, and the antibacterial mechanism of this coating against Staphylococcus aureus at the cellular level was clarified from the aspects of morphological characteristics, cell membrane function, energy metabolism, and DNA structure. The results showed that chitosan significantly improve the antibacterial effect. The number of S. aureus decreased by 6.89 (lg(CFU/mL)) after the coating solution containing 15 mg/L curcumin was exposed to 420 nm blue light for 5 min. Curcumin concentration and illumination time were the major factors affecting the antibacterial effect of this technique. The photodynamic inactivation treatment produced highly oxidizing reactive oxygen species (ROS), damaging the cell membrane and increasing membrane permeability, thus leading to the leakage of cell contents and cell shrinkage. It also led to an increase in intracellular ROS levels, which disrupted the structure of endogenous enzymes to trigger the breakdown of the bacterial defense system and the oxidative decomposition of macromolecules such as DNA and proteins, eventually causing the death of S. aureus. Therefore, chitosan/curcumin photodynamic coating has application potential in controlling foodborne pollution of S. aureus.

Phytoglycogen (PG), a carbohydrate polymer extracted from sugar-containing mutant seeds of plants, is a natural dendrimer-like glucan nanoparticle with high safety. The highly branched structure of phytoglycogen that is externally compact and internally loose provides it with high water retention, low viscosity, good dispersion stability, strong antioxidant and antibacterial activity, film-forming capacity, and excellent load capacity. Thus, in recent years, phytoglycogen has gradually become one of the research hotspots. However, there are few reports on the extraction, structural analysis, and comprehensive utilization of phytoglycogen so far. Therefore, this review focuses on the structure and properties of phytoglycogen, discusses the latest extraction methods for phytoglycogen, summarizes its application in foods, and provides an outlook on future research prospects, aiming to provide a theoretical basis for expanding the application of phytoglycogen.

Background Heart rate variability (HRV) is commonly used to evaluate the short-term prognosis of coronary artery diseaseas a well-known non-invasive indicator of cardiac autonomic function. Percutaneous coronary intervention (PCI) is a commonly usedsuigical treatment of coronary artery disease, however, major adverse cardiac event (MACE) such as malignant arrhythmias and recurrent myocardial infarction are common after suigical treatment. Although dual antiplatelet therapy (DAPT) can reduce the occurrence of MACE to a certain extent, it is prone to be complicated with gastrointestinal bleeding, and unable to consistently improve the prognosis of PCI. Ocular acupuncture can effectively reduce the duration and frequency of chest pain, and exercise therapy can enhance the function of heart and blood vessels. The application of ocular acupuncture and exercise combination therapy (OAECT) after PCI remains to be explored. Objective To investigate the effect of OAECT on postoperative heart rate variability and prognosis of patients treated with PCI. Methods A total of 32 CHD patients after PCI with moderate and low risk attending Hospital of Chengdu University of Traditional Chinese Medicine were selected and randomly divided into the OAECT group and drug treatment group in a 1∶1 allocation ratio. Patients in the OAECT group received OAECT in addition to DAPT, patients in the drug treatment group received DAPT alone, patients in both 2 groups completed the 2-week intervention. The data of patients was collectedas follows: (1) Baseline indicators: gender, age, height, weight, blood pressure, respiratory rate, interval between onset and intervention, education level, occupation, severity of coronary artery disease, and number of underlying diseases. (2) Main indicators: HRV within 24 h after PCI and on the day of the end of 2-week intervention, including the standard deviation of all normal to normal RR intervals (SDNN) , standard deviation of all 5-minute RR intervals (SDANN) , mean of the standard deviation of all NN intervals for all 5-min segment of 24 hours (SDNN index) , root mean square of difference between adjacent NN intervals (rMSSD) , percent of NN50 in the total number of NN intervals (PNN50) , high frequency (HF) , low frequency (LF) low frequency/high frequency (LF/HF) values. Prognosis at 2, 4, and 8 weeks after the intervention assessed by MACE, including cardiac or all-cause deaths, malignant arrhythmias such as ventricular tachycardia and ventricular fibrillation, severe heart failure, recurrent myocardial infarction, repeat PCI and chest pain recorded by telephone and outpatient consultations. (3) Secondary indicators: C-reactive protein (CRP) , N-terminal pro B type natriuretic peptide (NT-proBNP) , creatine kinase isoenzyme (CK-MB) , high-sensitivity troponin I (hs-TnI) . (4) Safety indicators: the occurrence of complications after PCI such as subcutaneous hematoma, skin lesions, muscle soreness, respiratory abnormalities and stroke, all the outcome indicators were measured within 24 hours after PCI and on the day of the end of 2-week intervention. Results There was no significant difference in LF/HF, SDNN, SDANN, SDNN index, LF, HF, RMSSD and PNN50 between the 2 groups (P>0.05) . There were significant differences in LF/HF, SDNN and SDANN (P0.05) . The incidence rates of MACE and adverse reactions in the OAECT group were lower than DAPT group (P

Fluoride-salt-cooled high-temperature reactor coupled with SCO2 Brayton cycle power generation system has the advantages of high inherent safety, high efficiency, compact structure, and waterless cooling. However, the cold end of the SCO2 Brayton cycle system operates near the critical point and is very sensitive to the cold end parameters, which seriously affects the performance of the cycle system. In addition, when the cold end parameters cross the critical point, the liquefied mass can seriously threaten the safety of the compressor and even the cycle system, therefore, the investigation of the characteristics of the cold end parameters during the dynamic process becomes the key to the safe and stable operation of the SCO2 Brayton cycle system. This paper took the SCO2 Brayton cycle system of a small fluoride-salt-cooled high-temperature reactor as the research object. Matlab/Simulink software was used as the simulation platform, and the Refprop interface was embedded to calculate physical properties. The one-dimensional dynamic simulation model was established for compressors, turbines, heat exchangers, reactors, and other thermal equipment through energy conservation and mass conservation. On this basis, the dynamic characteristics of the system under the disturbance of the cooling water flow of the SCO2 pre-cooler were studied, and the influence of the cold end parameters on the system performance during the variable load was explored. The results show that the disturbance of the cooling water flow of the SCO2 pre-cooler directly affects the inlet temperature of the main compressor, which in turn seriously affects the stable operation of the whole system, so it is necessary to impose certain control means to ensure the stability of the pre-cooler outlet temperature during the operation of the system. Due to the role of the thermal inertia of the reactor and the interaction between the reactor and the heat exchanger, the hot end of the system fluctuates obviously and then affects the cold end, so the reactor is the main reason for the longterm fluctuations of the cold end. In the process of load reduction, the cold end parameters of the system gradually approach the critical point, resulting in increasingly drastic changes in carbon dioxide density at the inlet of the main compressor, which leads to the sensitivity of the main compressor to the inlet temperature and inlet pressure gradually increases. At the low load state, the main compressor inlet temperature is disturbed by 1 ℃, the highest change of main compressor inlet density is 262 kg/m3, the highest change of main compressor outlet pressure is 7 MPa, and the highest change of main compressor efficiency is 6.82%. The main compressor inlet pressure is disturbed by 0.1 MPa, the highest change of main compressor inlet density is 228 kg/m3, the highest change of main compressor outlet pressure is 6.33 MPa, and the highest change of main compressor efficiency is 6.23%. However, the inlet temperature and inlet pressure of the main compressor have a small and almost negligible effect on the outlet temperature.