Automated extraction of Camellia oleifera crown using unmanned aerial vehicle visible images and the ResU-Net deep learning model.

As one of the four most important woody oil-tree in the world, Camellia oleifera has significant economic value. Rapid and accurate acquisition of C. oleifera tree-crown information is essential for enhancing the effectiveness of C. oleifera tree management and accurately predicting fruit yield. This study is the first of its kind to explore training the ResU-Net model with UAV (unmanned aerial vehicle) images containing elevation information for automatically detecting tree crowns and estimating crown width (CW) and crown projection area (CPA) to rapidly extract tree-crown information. A Phantom 4 RTK UAV was utilized to acquire high-resolution images of the research site. Using UAV imagery, the tree crown was manually delineated. ResU-Net model's training dataset was compiled using six distinct band combinations of UAV imagery containing elevation information [RGB (red, green, and blue), RGB-CHM (canopy height model), RGB-DSM (digital surface model), EXG (excess green index), EXG-CHM, and EXG-DSM]. As a test set, images with UAV-based CW and CPA reference values were used to assess model performance. With the RGB-CHM combination, ResU-Net achieved superior performance. Individual tree-crown detection was remarkably accurate (Precision = 88.73%, Recall = 80.43%, and F1score = 84.68%). The estimated CW (R 2 = 0.9271, RMSE = 0.1282 m, rRMSE = 6.47%) and CPA (R 2 = 0.9498, RMSE = 0.2675 m2, rRMSE = 9.39%) values were highly correlated with the UAV-based reference values. The results demonstrate that the input image containing a CHM achieves more accurate crown delineation than an image containing a DSM. The accuracy and efficacy of ResU-Net in extracting C. oleifera tree-crown information have great potential for application in non-wood forests precision management.

Angiographic uterine artery chemoembolization followed by vacuum aspiration: an efficient and safe treatment for managing complicated cesarean scar pregnancy.

PURPOSE: To evaluate uterine artery chemoembolization (UAEC) followed by vacuum aspiration as a conservative treatment for complicated cesarean scar pregnancy. METHODS: A retrospective review was performed of women presenting with cesarean scar pregnancy between January 2002 and December 2008. The medical record was evaluated to determine the method of treatment. RESULTS: During the time period studied, 13 women were identified who underwent UAEC followed by vacuum aspiration. 12 women successfully had bilateral UAEC followed by vacuum aspiration alone, one woman had unilateral UAEC followed by vacuum aspiration but subsequently required laparotomy. All 13 women were successfully cured and retained uterus, there was no case with severe complicating disease. With the follow-up period, two women who were planning future pregnancy conceived, and spontaneous abortion occurred in one of them during the first trimester, another had an elective cesarean delivery at term. CONCLUSIONS: UAEC combined with vacuum aspiration is technically feasible and may help avoid laparotomy in women with cesarean scar pregnancy.