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Based on Doppler radar observation and reanalysis data, the statistical characteristics of mesovortices (MVs) during the first rainy season (April–June) in Guangdong, South China, from 2017 to 2019 are studied, including their spatiotemporal distributions, structural features and favorable environmental conditions. The results show that the MVs usually exhibit short lifetimes; about 70% last for less than 30 min. The intensity and horizontal scale of the MVs are proportional to their lifetime. Long-lived MVs have larger horizontal scales and stronger intensities than short-lived ones. The MVs are mainly observed over the Pearl River Delta region, followed by western Guangdong Province, but relatively fewer in both eastern and northern Guangdong Province. The uneven spatial distribution of the MVs is closely related to the differences in the topographical features and the environment conditions over South China. MVs are prone to form over flat regions. The Pearl River Delta and eastern Guangdong regions are relatively flat compared to the more mountainous western and northern Guangdong regions. Moreover, the monsoonal south-westerlies, water vapor flux, atmospheric instability and vertical wind shear over southwest Guangdong are significantly larger than those in other regions and are favorable for the formation of MVs. The occurrence frequencies of MVs in central and southern parts of Guangdong display similar diurnal variations, reaching the peak during the late afternoon and early evening while dropping to the minimum overnight. However, the situation is opposite in northern Guangdong, with the peak overnight and the minimum during the late afternoon and early evening. The regional differences in diurnal variation are likely related to the moving direction of mesoscale convective systems (MCSs) in Guangdong. [ABSTRACT FROM AUTHOR]

Objective. To explore the effects of epidural anesthesia and general anesthesia on perioperative cognitive function and deep vein thrombosis (DVT) in patients undergoing total knee arthroplasty (TKA). Methods. Total of 68 patients undergoing TKA in our hospital from September 2019 to March 2021 were selected and divided into the control group under general anesthesia and the observation group under epidural anesthesia according to the different anesthesia methods, 34 patients in each group. TKA was selected in both groups and performed by the same group of physicians, anesthesiologists, and nursing staff. The mean arterial pressure (MAP), heart rate (HR), and blood oxygen saturation (SpO2) were observed immediately before anesthesia (T1), 30 min after anesthesia (T2), after surgery (T3), and 1 d after surgery (T4). The changes of platelet (PLC), fibrinogen (Fbg), prothrombin time (PT), activated partial thrombin time (APTT), and other coagulation indicators were recorded. The Montreal Cognitive Assessment (MoCA) scores before surgery and 1 d and 3 d after surgery were observed. The blood samples of the two groups were collected before surgery and 1 d and 3 d after surgery, and the levels of brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) in the peripheral blood of the two groups were measured by ELISA. The number of postoperative mental disorders and DVT in the two groups was calculated. Results. The MAP and HR of T4 were lower than those of T1, T2, and T3. The MAP of T2, T3, and T4 in the observation group was lower than that in the control group (P < 0.05), and the SpO2 of T1–T4 in the two groups did not change significantly, and there was no significant difference between the two groups (P > 0.05). Compared with T1, there was no significant difference in PLC, Fbg, and PT in the observation group T4 (P > 0.05), and APTT was lower than T1 (P < 0.05). The PLC, PT, and APTT of T4 in the control group were all lower than those of T1 (P < 0.05), and there was no significant difference between Fbg and T1 (P > 0.05). The PLC, Fbg, and PT of T4 in the observation group were higher than those in the control group, while APTT was lower than that in the control group (P < 0.05). The MoCA scores of patients in both groups on the 1st and 3rd day after operation were lower than those before operation, and the observation group was higher than that in the control group (P < 0.05). The BDNF and NGF of patients in both groups were lower than those before operation on the 1st day after operation, and the BDNF and NGF in the observation group were higher than those in the control group on the 1st and 3rd day after operation (P < 0.05). The mental disorder (2.94%) and DVT incidence (2.94%) in the observation group were lower than those in the control group (29.41%, 26.47%) (P < 0.05). Conclusion. Epidural anesthesia for patients with TKA can obtain better clinical effects, maintain stable hemodynamic and coagulation states, reduce stress response of patients at the same time, and reduce perioperative cognitive dysfunction and the incidence of DVT in patients. [ABSTRACT FROM AUTHOR]

Diabetic retinopathy (DR) is a leading cause of vision impairment and blindness among diabetics. We aimed to explore whether long-term exposure to residential greenness was beneficial to DR. We used data from a large-scale, cross-sectional screening survey conducted in 129 cities of 27 provincial regions of China from 2018 to 2021 among patients with diabetes. We measured residential greenness exposure as the 3-year average of annual maximum Normalized Difference Vegetation Index (NDVI) at a spatial resolution of 250 m. DR was assessed by ophthalmologists based on fundus photographs. The primary outcome was DR, and secondary outcome included DR severity status (i.e., nonproliferative and proliferative), hallmarks of retinal lesions and macular oedema. A total of 484,380 adult participants with diabetes were included in the current analysis, and 15.7% of them were diagnosed with DR. NDVI was inversely and linearly associated with DR prevalence, and an increment of 0.1 NDVI was associated with a 10% (9%–10%) decrease in DR prevalence. Significant and inverse associations were further found for nonproliferative and proliferative DR, hallmarks of lesions and macular oedema. The association between greenness and DR was stronger among participants who were older, obese, lived in the south, had longer duration of diabetes or did not take antidiabetic medications. This large-scale nationwide study provides the first-hand epidemiological evidence on the associations of residential greenness with DR. Our findings highlight the importance of residential greenness in alleviating DR risk especially in an era of aging and urbanization. • The first to examine the relationship between greenness and diabetic retinopathy (DR). • Greenness exposure was almost linearly associated with decreased odds of DR. • Greenness was inversely associated with nonproliferative and proliferative DR. • Greenness was inversely associated with hallmarks of DR and macular oedema. [ABSTRACT FROM AUTHOR]