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Regional ecological security pattern (ESP) can provide the basis for regional territorial spatial planning and urban ecological protection. Taking the Wuhan metropolitan area as the study area, a binary logistic regression model was used to quantify the evolutionary driving forces and transformation risk of ecological land. An identification framework of ecological source based on "quality-risk-demand" was constructed to identify ecological source by calculating the ecological land comprehensive value from three aspects of ecological land quality, degradation risk, and human demand. The ecological resistance surface was calculated according to land-use type and nighttime light data, further using circuit theory to identify the spatial range and its key areas of ecological corridors, and to identify the specific spatial range of ESP and their priority area. The results showed ecological sources were 382.4 km2, accounting for 17.3% of the metropolitan area. The area of ecological corridors in the terrestrial ecosystem (TEC) was 14.38 km2, with an average width of 77.8 m, including 4.99 km2 of pinch points and 3.71 km2 of barriers, indicating poor actual connectivity of the TEC. Ecological corridors in the aquatic ecosystem (AEC) were 107.67 km long, including 57.86 km of pinch points and 14.24 km of barriers, indicating poor substitutability of the AEC. Overall, the ESP of "three horizontals, three verticals, and four clusters" were identified, where sources, pinch points and barriers were the priority areas for protection and restoration in constructing it. Existing protection spaces were within the ecological source range, and the identification results of the ecological corridor were highly consistent with the actual situation, verifying the ecological significance of the identification framework. This study focuses on the needs of urban residents, combining the intrinsic quality and extrinsic risks of urban ecological land, proposes an integrated framework for identifying urban ecological sources, identifies the spatial range of ecological corridors and their key areas based on circuit theory, and attempts to provide a quantitative framework and case reference for ESP construction in other urban areas. • Quantifying the socioeconomic-natural driving forces of ecological land changes. • Creating a map of the transformation risk of urban ecological land. • Proposing "quality-risk-demand" framework to construct ecological security pattern. • Identifying specific spatial range of ecological corridor and its priority area. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to estimate the number of blood donors during the COVID-19 incubation period across China.Study Design and Methods: In this study, we developed a predictive model to estimate the number of blood donors during the COVID-19 incubation period among 34 provincial regions in China. Our main assumption was that blood donors of all ages in different regions have a stable blood donation intention and the same infection risk.Results: First, we estimated the number of blood donors during the COVID-19 incubation period in Wuhan city, Hubei Province, and China, from December 31, 2019 to March 17, 2020. Second, we compared the number of blood donors during the COVID-19 incubation period in all provinces across China. In addition, we found that if all RBCs, plasma, and cryoprecipitation were stored in isolation until the 14th day, the potential risk of SARS-CoV-2 transmission through blood transfusion was reduced by at least 65.77% after the blood donor safely passed the COVID-19 incubation period. Moreover, if the detection of SARS-CoV-2 RNA was carried out on all platelets, the potential risk would be reduced by 77.48%.Conclusions: Although the risk is low, with the rapid spread of the COVID-19 and the appearance of alarmingly high infectivity and a high fatality rate, appropriate measures should be taken by health departments to ensure the safety of clinical blood. [ABSTRACT FROM AUTHOR]