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Aerosol microorganisms are important constituents of aerosols. They participate in physical and chemical reactions in the air and are also closely related to disease transmission and human health. With the SARS-CoV-2 pandemic， aerosol microorganisms have become a public health topic of great concern. Studying the composition and influencing factors of the air microbiome therefore has significant public health implications. Due to the limitations of traditional technologies for sampling and determination， the aerosol microbiome has not been fully understood. However， with the development and maturity of high-throughput sequencing technology， the aerosol microbiome has shown promising research prospects. This article reviews the composition， characteristics， detection methods and influencing factors of aerosol microorganisms， providing basic knowledge for further research on the air microbiome. In-depth research on microbial aerosols has significant implications on urban air quality control， national security and public health.

Aviation medical rescue has the advantage of quick response and safe in emergency rescue and enters a stage of rapid growth. Given a late start of Aviation medical rescue in China, its shortcoming lies in dispatch system, equipment allocation, management system and personnel training. These papers summarized the development status of aviation medical rescue, and provided suggestions for the development of Aviation medical rescue business in China. (航空医疗救援具有迅速安全的优势, 目前在国内处于快速发展阶段, 由于起步较晚, 目前仍面临调度体制不完善、设备配给不足、管理制度欠缺、人员培训不规范等问题。本文主要综述了国内外航空医疗救援的发展现状, 并提出相关建议, 以期进一步促进国内航空医疗救援事业的发展。)

This paper summarized the key points of postoperative monitoring and management of a patient undergoing pulmonary thromboendarterectomy with extracorporeal circulation and deep hypothermic circulatory arrest. Key points of monitoring and management included Hemodynamic monitoring, respiratory monitoring, continued anticoagulation and related issues. It is required to enhance the monitoring of vital signs and carry our targeted interventions, in order to improve the postoperative rehabilitation of the patient. pulmonary arterial hypertension. (本文总结1例深低温体外循环下行肺动脉血栓内膜剥脱术患者术后监测管理要点, 包括血流动力学监测、呼吸系统监护、持续抗凝的注意事项及观察要点等。通过密切的监测, 及时掌握患者的恢复情况, 并针对性实施干预, 是促进患者术后康复的重要措施。)

The functionalization of aromatic N‐heterocycles through silylium activation demonstrates exceptional selectivity and efficiency. Density functional theory (DFT) calculations unveil the detailed silylium catalysis mechanism and elucidate the origins of selectivity in this reaction. The phosphoramidimidate sulfonamide (PADI) precatalyst orchestrates of the catalytic cycle via three elementary steps. The Brønsted acidity of precatalyst significantly influences both the formation of silylium‐based Lewis acid active species and the silylium activation of pyridine. Unlike disulfonimide (DSI)‐type precatalysts, both Tf2NH and PADI precatalysts with strong acidities can easily promote the generation of activated silylium pyridine species. A semi‐enclosed ′rigid' electronegative cavity in PADI‐type anions constructs a well‐defined recognition site, facilitating engagement with the positively charged silylium pyridine species. Due to the high electrophilicity and less steric demand at the C4‐position of the pyridine substrate, the product with C4‐regioselectivity was predominantly generated. [ABSTRACT FROM AUTHOR]

Objective: To investigate the mechanism of Baicalin on the hypoxic injury of H9c2 cardiomyocytes induced by co-balt chloride (CoCl2). Methods: Cobalt chloride (CoCl2) was used to establish a hypoxic injury model in cardiomyocytes, and different concentrations of Baicalin were added for culturing,respectively. The normoxic culture was set as the control group, and the cobalt chloride cultured H9c2 cardiomyocytes were set as the CoCl2 group. The hypoxic H9c2 cardiomyocytes pretreated with Ba- icalin and/or Y27632 (Rho kinase inhibitor) were set as the CoCl2+Baicalin group, CoCl2+Y27632 group and CoCl2+Baicalin+ Y27632 group. Cell proliferation was assessed using the cytotoxicity assay kit (CCK8) assay,and reactive oxygen species (ROS) levels were detected using a fluorescence method. The activity of superoxide dismutase (SOD) in cardiomyocytes was detected by WST-8. The concentration of propylene glycol (MDA) was determined by TBA method. Meanwhile, the expression of RhoA, ROCK1, ROCK2, TNF-α and IL-1 β were analyzed by Western blot as well. Results : After treatment of H9c2 cells for 24 h, 1 000 μmol/L CoCl2 and 75 μmol/L Baicalin showed better cell viability in the treatment of hypoxic injury of cardiomyocytes. The cell activity of the CoCl2 group was significantly lower than that of the control group, and the pre-protective effect of Baicalin on hypoxia-induced cells could significantly increase the cell activity. Compared with the control group, ROS expression level and MDA content in cardiomyocytes of the CoCl2 group increased,protein expression levels of RhoA, ROCK1, ROCK2, TNF-α and IL-1β up-regulated,and SOD activity decreased. Compared with the CoCl2 group, CoCl2+Baicalin could inhibit the expression of ROS and MDA content, up-regulate SOD activity, and down-regulate the expression levels of RhoA, ROCK1, ROCK2, TNF-α and IL-1β,while adding Y27632(Rho kinase inhibitor) significantly enhanced the protective effect of Baicalin. Conclusion: Ba- icalin could alleviate inflammatory and oxidative stress responses to CoCl2-induced injury in H9c2 cardiomyocytes, and its mecha- nism might be related to the inhibition of ROS-dependent RhoA/ROCK pathway. [ABSTRACT FROM AUTHOR]

BACKGROUND: In recent years, it has been reported that peroneus longus tendon can be used as a new graft material for anterior cruciate ligament reconstruction and can achieve the same effect as hamstring tendon. Therefore, it is necessary to systematically evaluate the two graft materials for anterior cruciate ligament reconstruction. OBJECTIVE: To evaluate the clinical effect of reconstruction of anterior cruciate ligament with peroneus longus tendon and hamstring tendon by meta-analysis. METHODS: We retrieved controlled clinical trials which compared the long peroneal tendons and hamstring tendons in reconstructing anterior cruciate ligament respectively in Chinese database (Wan Fang, CNKI, VIP, Chinese biological medicine) and English database (Ovid, PubMed, Web of Science, Embase, the Cochrane library). The retrieval time was from database creation to March 2019. Literature screening and evaluation and data extraction were performed by two evaluators. Meta-analysis was evaluated using Revman5.3 software. RESULTS AND CONCLUSION: (1) A total of 413 Chinese or English literatures were retrieved and 10 of them were included in the final analysis. Among 647 patients receiving anterior cruciate ligament reconstruction, 271 patients used peroneus longus tendon reconstruction and 376 patients used hamstring tendon reconstruction. (2) Meta-analysis results: postoperative functional score: There was significant difference in Lysholm score at postoperative 12 months (MD=1.23, 95%CI[0.31, 2.51], P=O.OOO 9) and IKDC score at postoperative 6 months (MD=3.19, 95%CI[0.07, 6.31], P=0.02) between peroneus longus tendon reconstruction and hamstring tendon groups. The occurrence of postoperative complications in the peroneus longus tendon group was significantly lower than that in the hamstring tendon group (OR=0.15, 95%CI[0.03, 0.69]. P=0.01). However, there were no significant differences in Tegnerscores, degree of joint motion, degree of joint relaxation at postoperative 6 and 12 months between peroneus longus tendon reconstruction and hamstring tendon groups. No significant difference was found in Lysholm score at postoperative 6 months and in IKDC score at postoperative 12 months between these two groups. The results showed that the clinical effect of peroneus longus tendon in reconstruction of anterior cruciate ligament was comparable to that of hamstring tendon; in the peroneus longus tendon reconstruction group, the Lysholm score at postoperative 12 months and IKDC score at postoperative 6 months were significantly superior to those in the hamstring tendon group. The incidence of postoperative complications in the peroneus longus tendon reconstruction group was lower than that in the hamstring tendon group. The peroneus longus tendon can be clinically recommended to substitute hamstring tendon in the reconstruction of the anterior cruciate ligament. However, the quality of included literatures is limited; therefore higher quality of evidence is required to validate this conclusion. [ABSTRACT FROM AUTHOR]

Soft/hard xMn0.6Zn0.4Fe2O4@(1−x)Sr0.85Ba0.15Fe12O19 (x = 0.15, 0.30, and 0.45) core/shell magnetic composites have been synthesized by the two-step ball-milling-assisted ceramic process. The products are characterized by x-ray powder diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), a vibrating sample magnetometer (VSM). The XRD analysis indicates the coexistence of ZnFe2O4 and SrFe12O19 phases. FT-IR results show that an Sr0.85Ba0.15Fe12O19 shell is on the surface of the Mn0.6Zn0.4Fe2O4 core. When Mn0.6Zn0.4Fe2O4@Sr0.85Ba0.15Fe12O19 precursor is calcined at 900°C, the crystallite size of obtained core/shell composites is between 33.50 ± 0.50 nm and 47.91 ± 0.72 nm in core Mn0.6Zn0.4Fe2O4 and between 59.34 ± 0.89 nm and 67.61 ± 1.01 nm in shell Sr0.85Ba0.15Fe12O19. Magnetic characterization indicates that the specific saturation magnetization of xMn0.6Zn0.4Fe2O4@(1−x)Sr0.85Ba0.15Fe12O19 composites decreases with the increase in mass ratio of soft-to-hard magnetic phases. Compared with bare Sr0.85Ba0.15Fe12O19 calcined at 950°C, the specific saturation magnetization of the composites is decreased and coercivity is markedly increased. This is attributed to the exchange-coupling interaction between the hard and soft magnetic phases due to formation of the core/shell structure. The 0.15Mn0.6Zn0.4Fe2O4@0.85Sr0.85Ba0.15Fe12O19 composite calcined at 700°C has higher squareness (Mr/Ms = 0.5401 ± 0.0065) and coercivity (4288.09 ± 42.88 Oe) values compared with the bare Sr0.85Ba0.15Fe12O19, which are useful for high-density magnetic recording and enhanced memory storage. [ABSTRACT FROM AUTHOR]