The effect of Bt Cry9Ee toxin on honey bee brood and adults reared in vitro, Apis mellifera (Hymenoptera: Apidae).

The effects of Bt Cry9Ee toxin on honey bee, Apis mellifera L., survival, developmental rate, larval weight, pollen consumption, and midgut bacterial diversity were tested in the laboratory. Honey bee larvae and adults were reared in vitro and fed a diet that contained Cry9Ee toxin at 0.01, 0.1, 1, and 10 mg/L. Cry9Ee toxin 0.01, 0.1, and 1 mg/L in diet used in this study may represent a value closer to field relevance and the highest concentration is unlikely to be encountered in the field and thus represent a worst case scenario. The dependent variables were compared for groups of honey bees feeding on treated diet and those feeding on negative control (no addition of a test substance), solvent control (0.01 mM Na2CO3), and positive control diet (dimethoate 45 mg/L). Bt Cry9Ee toxin did not affect survival or larval weight, and the result was great confidence in accepting the null hypothesis by power analysis. The effect on development rates and pollen consumption were the inconclusive results because the post-hoc power was less than 0.8. Furthermore, the midgut bacterial structure and compositions were determined using high-throughput sequencing targeting the V3-V4 regions of the 16S rDNA. All core honey bee intestinal bacterial class such as γ-Proteobacteria, Actinobacteria, α-Proteobacteria, Bacilli, ß-Proteobacteria, and Bacteroidia were detected, and no significant changes were found in the species diversity and richness between Cry9Ee treatments and laboratory control.

Classify Motor Imagery by a Novel CNN with Data Augmentation.

The brain-computer interface (BCI) based on electroencephalography (EEG) converts the subject's intentions into control signals. For the BCI, the study of motor imagery has been widely used. In recent years, a classification method based on a convolutional neural network (CNNs) has been proposed. However, most of the existing methods use a single convolution scale on CNN, and another problem that affects the results is limited training data. To solve these problems, we propose a mixed-scale CNN architecture, and a data augmentation method is used to classify the EEG of motor imagery. After classifying the BCI competition IV dataset 2b, the average classification accuracy is 81.52%. Compared with the existing methods, our method has a better classification result. This method effectively solves the problems existing in the existing CNN-based motor imagery classification methods, and it improves the classification accuracy.

Effects of three common pesticides on survival, food consumption and midgut bacterial communities of adult workers Apis cerana and Apis mellifera.

The acute and chronic toxicity of 3 common pesticides, namely, amitraz, chlorpyrifos and dimethoate, were tested in Apis mellifera and Apis cerana. Acute oral toxicity LC50 values were calculated after 24 h of exposure to contaminated syrup, and chronic toxicity was tested after 15 days of exposure to 2 sublethal concentrations of pesticides. The toxicity of the tested pesticides to A. mellifera and A. cerana decreased in the order of dimethoate > chlorpyrifos > amitraz. A. mellifera was slightly more sensitive to chlorpyrifos and dimethoate than A. cerana, while A. cerana was more sensitive to amitraz than A. mellifera. Chronic toxicity tests showed that 1.0 mg/L dimethoate reduced the survival of the two bee species and the food consumption of A. mellifera, while 1.0 mg/L amitraz and 1.0 mg/L chlorpyrifos did not affect the survival or food consumption of the two bee species. The treatment of syrup with amitraz at a concentration equal to 1/10th of the LC50 value did not affect the survival of or diet consumption by A. mellifera and A. cerana; however, chlorpyrifos and dimethoate at concentrations equal to 1/10th of their respective LC50 values affected the survival of A. cerana. Furthermore, intestinal bacterial communities were identified using high-throughput sequencing targeting the V3V4 regions of the 16S rDNA gene. All major honey bee intestinal bacterial phyla, including Proteobacteria (62.84%), Firmicutes (34.04%), and Bacteroidetes (2.02%), were detected. There was a significant difference in the microbiota species richness of the two species after 15 days; however, after 30 days, no significant differences were found in the species diversity and richness between A. cerana and A. mellifera exposed to 1.0 mg/L amitraz and 1.0 mg/L chlorpyrifos. Overall, our results confirm that acute toxicity values are valuable for evaluating the chronic toxicity of these pesticides to honey bees.

The Herbicide Glyphosate Negatively Affects Midgut Bacterial Communities and Survival of Honey Bee during Larvae Reared in Vitro.

Effects of glyphosate on survival, developmental rate, larval weight, and midgut bacterial diversity of Apis mellifera were tested in the laboratory. Larvae were reared in vitro and fed diet containing glyphosate 0.8, 4, and 20 mg/L. The dependent variables were compared with negative control and positive control (dimethoate 45 mg/L). Brood survival decreased in 4 or 20 mg/L glyphosate treatments but not in 0.8 mg/L, and larval weight decreased in 0.8 or 4 mg/L glyphosate treatments. Exposure to three concentrations did not affect the developmental rate. Furthermore, the intestinal bacterial communities were determined using high-throughput sequencing targeting the V3-V4 regions of the 16S rDNA. All core honey bee intestinal bacterial phyla such as Proteobacteria (30.86%), Firmicutes (13.82%), and Actinobacteria (11.88%) were detected, and significant changes were found in the species diversity and richness in 20 mg/L glyphosate group. Our results suggest that high concentrations of glyphosate are deleterious to immature bees.