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With the increasing demand for power in society, there is much live equipment in substations, and the safety and standardization of live working of workers are facing challenges. Aiming at these problems of scene complexity and object diversity in the real-time detection of the live working safety of substation workers, an adaptive multihead structure and lightweight feature pyramid-based network (AHLNet) is proposed in this study, which is based on YOLOV3. First, we take AH-Darknet53 as the backbone network of YOLOV3, which can introduce an adaptive multihead (AMH) structure, reduce the number of network parameters, and improve the feature extraction ability of the backbone network. Second, to reduce the number of convolution layers of the deeper feature map, a lightweight feature pyramid network (LFPN) is proposed, which can perform feature fusion in advance to alleviate the problem of feature imbalance and gradient disappearance. Finally, the proposed AHLNet is evaluated on the datasets of 16 categories of substation safety operation scenarios, and the average prediction accuracy MAP50reaches 82.10%. Compared with YOLOV3, MAP50is increased by 2.43%, and the number of parameters is 90 M, which is only 38% of the number of parameters of YOLOV3. In addition, the detection speed is basically the same as that of YOLOV3, which can meet the real-time and accurate detection requirements for the safe operation of substation staff.

MicroRNAs play critical roles in the occurrence and progression in various cancers including colorectal cancer. Here, we found that microRNA-30a expression was significantly downregulated in colorectal cancer tissues compared to adjacent noncancerous tissues, and the suppression levels of microRNA-30a were significantly associated with tumor differentiation and lymph node metastasis. We also discovered that the expression level of microRNA-30a was inversely proportional to the invasive potential of several colorectal cancer cell lines. Moreover, overexpression of microRNA-30a in colorectal cancer cells inhibited activity of cell migration and invasion. Luciferase reporter assay confirmed metadherin could be a direct target of microRNA-30a, as the overexpression of microRNA-30a decreased metadherin expression at both the protein and messenger RNA levels. Furthermore, the knockdown of metadherin expression in SW620 significantly decreased cell metastasis and invasion. The upregulation of metadherin at the protein level negatively correlated with the expression of microRNA-30a in colorectal cancer tissues, and this upregulation could partially attenuate the effect induced by microRNA-30a. These findings indicate that microRNA-30a may act as a tumor suppressor in colorectal cancer and that microRNA-30a represses cell migration and invasion by decreasing metadherin, highlighting the therapeutic potential of microRNA-30a and metadherin in colorectal cancer treatment.