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In this paper, four widely used temporal compositing algorithms, i.e. median, maximum NDVI, medoid, and weighted scoring-based algorithms, were evaluated for annual land cover classification using monthly Landsat time series data. Four study areas located in California, Texas, Kansas, and Minnesota, USA were selected for image compositing and land cover classification. Results indicated that images composited using weighted scoring-based algorithms have the best spatial fidelity compared to other three algorithms. In addition, the weighted scoring-based algorithms have superior classification accuracy, followed by median, maximum NDVI, and medoid in descending order. However, the median algorithm has a significant advantage in computational efficiency which was ∼70 times that of weighted scoring-based algorithms, and with overall classification accuracy just slightly lower (∼0.13% on average) than weighted scoring-based algorithms. Therefore, we recommended the weighted scoring-based compositing algorithms for small area land cover mapping, and median compositing algorithm for the land cover mapping of large area considering the balance between computational complexity and classification accuracy. The findings of this study provide insights into the performance difference between various compositing algorithms, and have potential uses for the selection of pixel-based image compositing technique adopted for land cover mapping based on Landsat time series data. [ABSTRACT FROM AUTHOR]

Objective. The purpose of this meta-analysis was to investigate the effect of periprocedural myocardial injury (PPMI) on long-term all-cause mortality in patients undergoing transcatheter aortic valve replacement (TAVR) and to explore potential factors associated with mortality risk. Design. The PubMed, Embase, and Cochrane Library databases were searched up to April 2022. Studies reporting the effect of PPMI on the risk of long-term all-cause mortality were included. The summary odds ratio (OR) was calculated using a random effects model. Additionally, meta-regression and subgroup analyses were conducted according to specific research characteristics to explore sources of heterogeneity. Results. Fourteen studies involving 6,415 patients who underwent TAVR showed that the occurrence of PPMI was associated with a higher risk of long-term mortality. Subgroup analysis showed that in the group of aged ≥82 years, men accounted for less than 50%, coronary artery disease patients accounted for more than 50%, and the proportion of patients with chronic kidney disease accounted for more than 60%, the proportion of patients with atria fibrillation accounted for less than 30%, and the Society of Thoracic Surgeons predicted risk of mortality score was >8 points, patients with PPMI had higher long-term all-cause mortality than those without PPMI. Conclusions. Among the patients who underwent TAVR, those who developed PPMI had higher long-term all-cause mortality. [ABSTRACT FROM AUTHOR]