Improved edge lightweight YOLOv4 and its application in on-site power system work

A“cloud-edge-end”collaborative system architecture is adopted for real-time security management of power system on-site work,and mobile edge computing equipment utilizes lightweight intelligent recognition algorithms for on-site risk assessment and alert.Owing to its lightweight and fast speed,YOLOv4-Tiny is often deployed on edge computing equipment for real-time video stream detection;however,its accuracy is relatively low.This study proposes an improved YOLOv4-Tiny algorithm based on attention mechanism and optimized training methods,achieving higher accuracy without compromising the speed.Specifically,a convolution block attention module branch is added to the backbone network to enhance the feature extraction capability and an efficient channel attention mechanism is added in the neck network to improve feature utilization.Moreover,three optimized training methods:transfer learning,mosaic data augmentation,and label smoothing are used to improve the training effect of this improved algorithm.Finally,an edge computing equipment experimental platform equipped with an NVIDIA Jetson Xavier NX chip is established and the newly developed algorithm is tested on it.According to the results,the speed of the improved YOLOv4-Tiny algorithm in detecting on-site dress code compliance datasets is 17.25 FPS,and the mean average precision(mAP)is increased from 70.89%to 85.03%.

Transcriptome and metabolome analysis reveal that oral secretions from Helicoverpa armigera and Spodoptera litura influence wound-induced host response in cotton

Cotton(Gossypium hirsutum)is an important fiber crop worldwide.Insect attack causes cotton yield and quality losses.However,little is known about the mechanism of cotton response to insect attack.We simulated insect feeding by applying insect oral secretions(OS)to wounds,and combined transcriptome and metabolome analysis to investigate how OS from two major pest species(Helicoverpa armigera and Spodoptera litura)affect cotton defense responses.We found that respectively 12,668 and 13,379 genes were differentially expressed in comparison with wounding alone.On addition of OS,the jasmonic acid signaling pathway was rapidly and strongly induced,whereas genes involved in salicylic acid biosynthesis were downregulated.On constructing a coexpression gene network,we identified a hub gene encoding a leucine-rich repeat receptor kinase that may play an important role in early signal recognition and transduction.OS from the two insect species altered the abundance of flavonoid-related compounds in different patterns.Gossypol remained in lower concentration after OS application than after wounding alone,suggesting a suppressive effect of OS on cotton defense response.This study illustrated transcriptional and metabolic changes of cotton in responding to OS from two chewing insect species,identified potential key response genes,and revealed evidence for OS inhibition of wounding-induced cotton defense response.

Identification and selection of resistance to Bemisia tabaci among 550 cotton genotypes in the field and greenhouse experiments

Plants have developed sophisticated systems to cope with herbivore challenge, including morphological barriers and secondary metabolites to reduce damage. In this study, 550 Gossypium genotypes were evaluated for whitefly(Bemisia tabaci) resistance in five experiments including two in the field and three in the greenhouse, with23 resistant and 19 susceptible genotypes selected.Whitefly-resistance index determination showed that a leaf having a high density of hairs had resistance to whitfly egg/nymph production. Longer leaf hairs were also important for resistance. This study revealed that okra shaped leaves reduced adult whitefly oviposition preference, while glabrous leaves and high hair density helped not only in the reduction of the adults but also decreased oviposition preference. Gossypol was also observed to be involved in the reduction of adult whitefly development and/or survival.

A near-complete genome assembly of Catharanthus roseus and insights into its vinblastine biosynthesis and high susceptibility to the Huanglongbing pathogen

Dear Editor,Catharanthus roseus,an important medicinal plant native to Madagascar,is the sole source of the two important anticancer drugs vinblastine and vincristine,which are synthesized by the monoterpene-derived indole alkaloid(MIA)pathway(Das et al.,2020).It is also an important model plant for the study of Huanglongbing(HLB),a devastating citrus disease that causes severe economic losses worldwide(Ma et al.,2022).Vincristine is an FDA-approved drug that has been used for acute lymphocytic leukemia,lymphoid blast crisis of chronic myeloid leukemia,and Hodgkin’s/non-Hodgkin’s lymphoma(Below and M Das,2021).