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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.

In order to investigate the intrinsic relationship between protein characteristics and quality changes during the hot air drying of shrimp, Penaeus vannamei was dried by hot air at 55 ℃ after being boiled in 3% salt solution for 2 minutes. We studied changes in the microstructure and quality of shrimp, and systematically investigated changes in the oxidative degradation degree, intramolecular valence bonds, and secondary and tertiary structure of protein. The results showed that the drying treatment gradually decreased the L*, a* and b* values of shrimp, and changed the texture characteristics, and the hardness, adhesiveness and chewiness were increased to 344.78 N, 45.01 mJ and 116.50 mJ at the end of drying, respectively. In addition, oxidative denaturation and degradation of proteins occurred; the total sulfhydryl content decreased to 0.36 μmol/g at the end of drying, while the carbonyl content increased to 2.03 nmol/mg protein, and the trichloroacetic acid (TCA)-soluble peptide content increased to 0.91 μmol/g. The protein structure was significantly changed; the relative contents of ionic and hydrogen bonds decreased, the relative contents of hydrophobic and disulfide bonds increased, the secondary structure was transformed from α-helix to β-fold, β-turn and random coil, the intensity of tryptophan fluorescence decreased, and the tertiary structure was also changed. Pearson correlation analysis showed that the color changes were mainly related to protein oxidation and protein degradation and denaturation significantly affected the textural properties of shrimp. This study can provide theoretical support for further improving the quality of dried shrimp products.

In this study, we experimentally showcase the microfiber evanescent-field photothermal gas detection by exploiting all-fiber MHz-level frequency shift scheme. Based on the acousto-optic interaction effect, the low-frequency shifts of 0.9 MHz and 1.83 MHz can be obtained through the cyclic conversion between the transverse core modes LP01 and LP11 in the few-mode fiber. Our proposed all-fiber frequency shifters show flexible MHz-level up(down) frequency shifts with superior sideband rejection ratio (over 40 dB) and low insertion loss (less than 1 dB). Furthermore, an all-fiber heterodyne interferometric detection system is implemented by leveraging the above low-frequency shifters, in which around 1-μm-diameter microfiber is investigated for photothermal gas detection. A pump-probe configuration is employed to obtain the photothermal effect induced by the gas absorption of the modulated evanescent field. By demodulating the phase of the beat signal output by the interferometer, an equivalent detection limit (1σ) of 32 ppm and a response time of 22 s are achieved for ammonia, as well as 0.24 % instability within 48 pump cycles. Given its compact all-fiber configuration and high sensitivity with fast response, the experimental results can pave the way for widespread applications like heterodyne detection, fiber optical sensors, and interplanetary coherent communications.

The major bioactive components and flavor characteristics of Toona sinensis buds from different production areas such as Sichuan, Shaanxi, Shandong, Shanxi, Hebei and Yunnan were explored. The overall odor was evaluated by sensory evaluation, and the volatile components were analyzed using electronic nose and gas chromatography-ion mobility spectrometry (GC-IMS) in order to analyze the differences in the flavor characteristics of T. sinensis buds from different production areas. The sensory evaluation results showed that the odor of T. sinensis buds from Yunnan was rich and pleasant, while the odor of T. sinensis buds from Shaanxi was irritating. The results of electronic nose analysis showed that the contents of aromatics and long-chain alkanes in T. sinensis buds from the six production areas were similar, while the contents of nitrogen oxides and sulfides were quite different. A total of 76 volatile substances were identified by GC-IMS, including 12 alcohols, 10 esters, 9 pyrazines, 9 ketones, 8 terpenoids, 7 organic sulfides, 7 aldehydes, 6 acids, 4 phenols and 4 other compounds. The principal component analysis (PCA) of electronic nose and GC-IMS data showed that the flavor of T. sinensis buds from Yunnan was unique, and the flavors of T. sinensis buds from Sichuan, Shaanxi and Shandong were similar. T. sinensis buds from Shanxi was different from those from other geographical origins, and the content of flavor substances in T. sinensis buds from Hebei was low. The results of this study may provide a theoretical basis for the screening of T. sinensis for deep processing.

Abstract In early spring or winter, supercooled raindrops impact on transmission lines and accumulate ice on its surface frequently, which may induce galloping vibration occurs. Studies on collision coefficient or icing mostly focus on key parameters of wind velocities, raindrop sizes and conductor diameters, whereas few involve electric field. In order to clarify the influence of the direct current electric field on the collision coefficient of transmission lines, a calculation formula of the mass flow rate of raindrops was proposed, and the process of raindrops hitting the conductor surface is numerically calculated by the Euler–Lagrange method. The effects of electric field intensity, conductor diameter, cross‐sectional shape, wind velocity, raindrop diameter and charge density on the collision coefficient of transmission lines are analyzed. The results show that the collision coefficient decreases with the increase of electric intensity. As the electric intensity increases from 0 to 66.7 kV/cm, the collision coefficient decreases about 33%. Because of the repulsion between the conductor and raindrops, more raindrops move away from the conductor surface and collision coefficient decreases. The collision coefficient of the actual conductor under no electric field is slightly smaller than that of the simplified circular cross‐section. Under DC electric field, the collision coefficient of the conductor decreases with wind velocity increase up to 8 m/s. Beyond that threshold, the collision coefficient is almost constant.

Background The prevalence of neurodevelopmental disorders in premature infants is high, and there is an urgent need to improve neurodevelopmental outcomes of them. There are few reports on amplitude-integrated electroencephalography (aEEG) -assessed effect of multisensory (MS) interventions on brain function of premature infants by aEEG. Objective To evaluate the effect of MS interventions on improving brain function of premature infants. Methods A single-center, randomized controlled trial was conducted. One hundred and twenty-six premature infants who were admitted to Department of Pediatrics, the First Affiliated Hospital of Guangxi Medical University from October 2020 to September 2021 were selected and randomly divided into control group (n=63) and intervention group (n=63) by random numbers according Excel. Both groups received routine treatment and nursing care, the intervention group additionally received MS interventions developed by our team (including auditory, tactile, visual and vestibular interventions) , twice a day, 15 minutes each time. The time of intervention lasted for at least 7 days for both groups. Before and 7 days after the intervention, the lower boundary voltage, bandwidth, and aEEG score during the quiet sleep (QS) period and active sleep (AS) period, average time and total time of QS period were monitored by AEEG. The Neonatal Behavioral Neurological Assessment (NBNA) was used to evaluate the neurobehavior. The Gesell Developmental Schedules (GDS) was used to evaluate the development quotient at the corrected age of one month. Results 119 premature infants completed the study, including 59 cases in the control group and 60 cases in the intervention group. Seven days after intervention, intervention group had higher lower boundary voltage〔 (5.47±0.92) μV vs (5.10±0.87) μV〕and narrower bandwidth〔 (18.90±1.90) μV vs (19.78±2.50) μV〕 during QS period than the control group (P0.05) . Moreover, intervention group had longer average time of QS period 〔 (25.67±6.95) min vs (23.29±4.87) min〕 and longer total time of QS period 〔 (62.80±18.89) min vs (55.27±20.65) min〕 than control group (P< 0.05) . Intervention group also had higher total score of NBNA 〔 (34.82±2.97) vs (33.12±3.49) 〕 (P< 0.05) . At the corrected age of one month, intervention group had higher developmental quotient scores in terms of gross motor 〔 (52.83±10.93) vs (48.83±10.11) 〕, fine motor〔 (51.67±11.05) vs (47.71±9.15) 〕, adaptive development 〔 (55.28±11.65) vs (50.31±10.14) 〕, language 〔 (53.40±11.29) vs (49.41±9.82) 〕 and personal-social〔 (53.57±10.57) vs (49.51±9.35) 〕 than the control group (P

We previously reported that the peptide ST2-104 (CBD3, for Ca2+ channel-binding domain 3), derived from the collapsin response mediator protein 2 (CRMP2)–a cytosolic phosphoprotein, protects neuroblastoma cells against β-amyloid (Aβ) peptide-mediated toxicity through engagement of a phosphorylated CRMP2/NMDAR pathway. Abnormal aggregation of Aβ peptides (e.g., Aβ25–35) leads to programmed cell death (apoptosis) as well autophagy–both of which contribute to Alzheimer's disease (AD) progression. Here, we asked if ST2-104 affects apoptosis and autophagy in SH-SY5Y neuroblastoma challenged with the toxic Aβ25–35 peptide and subsequently mapped the downstream signaling pathways involved. ST2-104 protected SH-SY5Y cells from death following Aβ25–35 peptide challenge by reducing apoptosis and autophagy as well as limiting excessive calcium entry. Cytotoxicity of SHY-SY5Y cells challenged with Aβ25–35 peptide was blunted by ST2-104. The autophagy activator Rapamycin blunted the anti-apoptotic activity of ST2-104. ST2-104 reversed Aβ25-35-induced apoptosis via inhibiting Ca2+/CaM-dependent protein kinase kinase β (CaMKKβ)-mediated autophagy, which was partly enhanced by STO-609 (an inhibitor of CaMKKβ). ST2-104 attenuated neuronal apoptosis by inhibiting autophagy through a CaMKKβ/AMPK/mTOR signaling hub. These findings identify a mechanism whereby, in the face of Aβ25–35, the concerted actions of ST2-104 leads to a reduction in intracellular calcium overload and inhibition of the CaMKKβ/AMPK/mTOR pathway resulting in attenuation of autophagy and cellular apoptosis. These findings define a mechanistic framework for how ST2-104 transduces "outside" (calcium channels) to "inside" signaling (CaMKKβ/AMPK/mTOR) to confer neuroprotection in AD. [ABSTRACT FROM AUTHOR]