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Backfat thickness (BF) is closely related to the service life and reproductive performance of sows. The dynamic monitoring of sows' BF is a critical part of the production process in large-scale pig farms. This study proposed the application of a hybrid CNN-ViT (Vision Transformer, ViT) model for measuring sows' BF to address the problems of high measurement intensity caused by the traditional contact measurement of sows' BF and the low efficiency of existing non-contact models for measuring sows' BF. The CNN-ViT introduced depth-separable convolution and lightweight self-attention, mainly consisting of a Pre-local Unit (PLU), a Lightweight ViT (LViT) and an Inverted Residual Unit (IRU). This model could extract local and global features of images, making it more suitable for small datasets. The model was tested on 106 pregnant sows with seven randomly divided datasets. The results showed that the CNN-ViT had a Mean Absolute Error (MAE) of 0.83 mm, a Root Mean Square Error (RMSE) of 1.05 mm, a Mean Absolute Percentage Error (MAPE) of 4.87% and a coefficient of determination (R-Square, R2) of 0.74. Compared to LviT-IRU, PLU-IRU and PLU-LviT, the CNN-ViT's MAE decreased by more than 12%, RMSE decreased by more than 15%, MAPE decreased by more than 15% and R² improved by more than 17%. Compared to the Resnet50 and ViT, the CNN-ViT's MAE decreased by more than 7%, RMSE decreased by more than 13%, MAPE decreased by more than 7% and R2 improved by more than 15%. The method could better meet the demand for the non-contact automatic measurement of pregnant sows' BF in actual production and provide technical support for the intelligent management of pregnant sows. [ABSTRACT FROM AUTHOR]

Pyridotriazoles are an important subclass of azacyclic compounds. Although known in early 1950s, these compounds aroused little attention in synthetic chemistry for a long time. This situation has changed during the past years as ever‐increasing recognitions on their rich properties and reactivities. Particularly, the recent exploration on their potentials as carbene or metal carbene precursors in denitrogenative transformations catalytically or non‐catalytically has met considerable success. A lot of new synthetic approaches towards azacyclic compounds such as indolizines, imidazopyridines, pyridoisoquinolinones and pyridoindoles as well as a wide range of functionalized pyridines have been established based on the transformations of pyridotriazoles. Meanwhile, a considerable number of new reactions are developed for the synthesis of pyridotriazoles. In particular, the development of new transition‐metal catalyzed tandem reactions has enabled selective generation of diverse pyridotriazoles in efficient manners from simple starting materials. This review surveys main advances in this field over the last two decades and aims to provide an up‐to‐date overview on the knowledge of pyridotriazole chemistry. [ABSTRACT FROM AUTHOR]

Physiological repair of large-sized bone defects is great challenging in clinic due to a lack of ideal grafts suitable for bone regeneration. Decalcified bone matrix ( DBM ) is considered as an ideal bone regeneration scaffold, but low cell seeding efficiency and a poor osteoinductive microenvironment greatly restrict its application in large-sized bone regeneration. To address these problems, we proposed a novel strategy of bone regeneration units ( BRUs ) based on microgels produced by photo-crosslinkable and microfluidic techniques, containing both the osteogenic ingredient DBM and vascular endothelial growth factor ( VEGF ) for accurate biomimic of an osteoinductive microenvironment. The physicochemical properties of microgels could be precisely controlled and the microgels effectively promoted adhesion, proliferation, and osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) in vitro . BRUs were successfully constructed by seeding BMSCs onto microgels, which achieved reliable bone regeneration in vivo . Finally, by integrating the advantages of BRUs in bone regeneration and the advantages of DBM scaffolds in 3D morphology and mechanical strength, a BRU -loaded DBM framework successfully regenerated bone tissue with the desired 3D morphology and effectively repaired a large-sized bone defect of rabbit tibia. The current study developed an ideal bone biomimetic microcarrier and provided a novel strategy for bone regeneration and large-sized bone defect repair., Competing Interests: The authors declare no competing interests., (© 2021 The Authors.)