FV-MViT: Mobile Vision Transformer for Finger Vein Recognition.

In addressing challenges related to high parameter counts and limited training samples for finger vein recognition, we present the FV-MViT model. It serves as a lightweight deep learning solution, emphasizing high accuracy, portable design, and low latency. The FV-MViT introduces two key components. The Mul-MV2 Block utilizes a dual-path inverted residual connection structure for multi-scale convolutions, extracting additional local features. Simultaneously, the Enhanced MobileViT Block eliminates the large-scale convolution block at the beginning of the original MobileViT Block. It converts the Transformer's self-attention into separable self-attention with linear complexity, optimizing the back end of the original MobileViT Block with depth-wise separable convolutions. This aims to extract global features and effectively reduce parameter counts and feature extraction times. Additionally, we introduce a soft target center cross-entropy loss function to enhance generalization and increase accuracy. Experimental results indicate that the FV-MViT achieves a recognition accuracy of 99.53% and 100.00% on the Shandong University (SDU) and Universiti Teknologi Malaysia (USM) datasets, with equal error rates of 0.47% and 0.02%, respectively. The model has a parameter count of 5.26 million and exhibits a latency of 10.00 milliseconds from the sample input to the recognition output. Comparison with state-of-the-art (SOTA) methods reveals competitive performance for FV-MViT.

Coexistence of cry9 with the vip3A Gene in an Identical Plasmid of Bacillus thuringiensis Indicates Their Synergistic Insecticidal Toxicity.

Bacillus thuringiensis (Bt) strains may express several insecticidal proteins with synergistic features, achieving high insecticidal toxicity and delaying development of resistance in insect pests. Previous work showed that Cry9Aa and Vip3Aa proteins present synergistic activity against Chilo suppressalis. In this study, genome-wide analysis of 489 Bt genomes revealed that cry9A was associated with the vip3A gene in seven Bt strains. Among all Bt genomes analyzed, not a single strain was found to have the cry9A gene alone without the presence of the vip3A gene. The complete genome sequencing of two Bt strains, 4AP1 and 4AO1, revealed that cry9A and vip3A genes were located in the same plasmid in both strains. The genome context analysis suggested a recombination mechanism responsible for the insertion of the cry9A gene into the plasmid containing vip3A. The coexistence of Cry9A with Vip3A proteins in strain 4AP1 was confirmed by liquid chromatography-tandem mass spectrometry and western blot analyses. Furthermore, another Cry9 protein codified by the gene in the identical plasmid also showed synergistic activity with the Vip3A protein. Overall, our results support that cry9 genes coexisted with vip3A and that complete genome sequencing combined with protein expression analysis may be used to identify associations of insecticidal proteins with potential synergistic toxicity.

An improved PCR-restriction fragment length polymorphism (RFLP) method for the identification of cry1-type genes.

The cry1-type genes of Bacillus thuringiensis represent the largest cry gene family, which contains 50 distinct holotypes. It is becoming more and more difficult to identify cry1-type genes using current methods because of the increasing number of cry1-type genes. In the present study, an improved PCR-restriction fragment length polymorphism (PCR-RFLP) method which can distinguish 41 holotypes of cry1-type genes was developed. This improved method was used to identify cry1-type genes in 20 B. thuringiensis strains that are toxic to lepidoptera. The results showed that the improved method can efficiently identify single and clustered cry1-type genes and can be used to evaluate cry1-type genes in novel strain collections of B. thuringiensis. Among the detected cry1-type genes, we identified four novel genes, cry1Ai, cry1Bb, cry1Ja, and cry1La. The bioassay results from the expressed products of the four novel cry genes showed that Cry1Ai2, Cry1Bb2, and Cry1Ja2 were highly toxic against Plutella xylostella, whereas Cry1La2 exhibited no activity. Moreover, Cry1Ai2 had good lethal activity against Ostrinia furnacalis, Hyphantria cunea, Chilo suppressalis, and Bombyx mori larvae and considerable weight loss activity against Helicoverpa armigera.