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Insect infestations cause substantial changes in the leaves they attack, but the effects of insect infestation on photosynthesis and gene expression in the whole infestation period are rarely reported. In this study, the effects of poplar aphid (Chaitophorus populialbae Boyer de Fonscoloube) on photosynthetic rate and gene expression of Populus alba var. pyramidalis were studied, from 2 to 36 days after low-density aphid inoculation (DAI). The results revealed a dynamic change of photosynthesis in poplar after aphid infestation: compensatory increased at 8 DAI, was inhibited at 17 DAI, but repaired after 21 DAI. Aphid infestation promoted the expression of the majority of differentially expressed genes (DEGs) at 4, 6, 8, and 21 DAI. The DEGs were enriched into a plant–pathogen interaction, plant hormone signal transduction, and MAPK signaling pathway, suggesting a significant but transient resistance to disease or other stresses. Photosynthesis-related DEGs were downregulated at 8 DAI, which might result in photosynthetic inhibition at 17 DAI. The expression of flavonoid biosynthesis-related DEGs dynamic changed from all downregulated at 2 DAI to almost all upregulated at 21 DAI, suggesting a persistent resistance to insect infestation. This study reveals dynamic changes in photosynthesis, resistance to pathogens, and insects in poplar leaves after aphid infestation. [ABSTRACT FROM AUTHOR]

In complex and heterogeneous geoenvironments, landslides exhibit varying features in different environments, and data in landslide inventories are imbalanced. Existing data-driven landslide susceptibility evaluation (LSE) methods overlook environmental heterogeneity and cannot reliably predict regions with few samples. Alternatively, global random negative sampling strategies may produce imbalanced positive and negative samples in some environments, contributing to inaccurate predictions. This article proposes a graph neural network (GNN) constrained by environmental consistency (GNN-EC) to overcome these problems. The GNN-EC consists of graphs with nodes, and edges. A graph represents the environmental relationships in the study area. Nodes are geographic units delineated from terrain polygon approximation. Edges capture the relationships between node-pairs. Additionally, the weights of edges reflect the similarity between two node environments. A GNN aggregates node information in the graph for LSE. Our experiment showed that the proposed method outperformed the common machine learning methods: increasing prediction accuracy by approximately 7, 5–6 and 3–4% compared to the artificial neural network (ANN), the support vector machine (SVM) and the random forest (RF), respectively. Moreover, our method can maintain high prediction accuracy, even with a small training set. [ABSTRACT FROM AUTHOR]

In the current technological world, artificially intelligent deep learning techniques are adapted in many fields. This advanced technology is also used in the field of education. In this study, people will conduct research on the optimization of ideological and political education strategies in colleges and universities based on deep learning. Deep learning is often a machine learning technique that uses artificial neural networks that allow a machine to imitate human behaviour. Ideological and political education deals with the social studies implied by the political scenario. Ideological and political education aims to teach the younger generation social, economic, and political awareness. In our proposed system, people will deploy the deep learning algorithm named brute force algorithm to optimize ideological and political education in colleges and universities. The teaching optimization is performed by automating the training of the deep learning model. The results were compared with the existing K-means algorithm, and it is observed that the proposed system has achieved a higher accuracy of 99.12% in optimizing the educational strategies. [ABSTRACT FROM AUTHOR]

Agrilus mali Matsumura is a wood-boring beetle that aggressively attacks species of the genus Malus, that has recently caused serious damage to the wild apple tree M. sieversii (Lebed.) in the western Tianshan Mountains in Xinjiang. It was first detected there in the early 1990s and spread rapidly, being thus considered a regional invasive pest. To explore the possible outbreak mechanism of the local population and characterize the genetic differentiation of A. mali across different regions of China, we used three mitochondrial genes (COI , COII , and CytB) to investigate the genetic diversity and genetic structure of 17 A. mali populations containing 205 individuals collected from five Chinese provinces. Among them, nine populations were from the western Tianshan Mountains. Ultimately, of the 136 pairwise F st comparisons, 99 showed high genetic differentiation among overall populations, and Tianshan populations exhibited significant differentiation with most of the non-Tianshan populations. Furthermore, A. mali populations represented relatively abundant haplotypes (54 haplotypes). Nine populations from the Tianshan Mountains showed 32 haplotypes (26 of which were unique), displaying relatively high genetic diversity. Additionally, the Mantel test revealed population genetic differentiation among either overall populations or the Tianshan Mountains populations, likely caused by geographical isolation. Phylogenic relationships showed that all populations clustered into three clades, and Tianshan Mountains populations, including CY, occupied one of the three clades. These results suggest that A. mali in the western Tianshan region has possibly been present in the area for a long period, and may not have been introduced recently. Highly frequent gene flows within Tianshan populations are possibly caused by human activities and may enhance the adaptability of A. mali along the western Tianshan Mountains, leading to periodic outbreaks. These findings enhance our understanding of jewel beetle population genetics and provide valuable information for pest management. [ABSTRACT FROM AUTHOR]

Wild apple forests in the Tian Shan Mountains in north‐western China have been adversely affected by an unknown disease in recent years. Symptoms attributed to this disease that affects wild apple trees include xylem browning and dieback which are suggestive of infection by Fusarium species. Therefore, the research team conducted the first survey for Fusarium in the afflicted wild apple forests. Twig samples with symptoms of xylem browning and dieback were collected in the Xinyuan, Gongliu, Yining and Huocheng Counties of Xinjiang Uighur Autonomous Region in China. Based on phylogenetic analyses and morphological observation, sixty strains of Fusarium accounted for 48% of the total number of fungi isolated from samples were subsequently classified into six species including twenty‐four F. avenaceum, seventeen F. solani, ten F. tricinctum, five F. proliferatum, two F. sporotrichioides and two unfamiliar Fusarium sp. 1. The five previously known species of Fusarium were then tested for pathogenicity to leaves and twigs in vitro. The results indicated that all of the species, except for F. tricinctum, can cause obvious lesions on the leaves of host plants and on the twigs of Fuji and wild apple. This is the first report of Fusarium species pathogenicity in Xinjiang wild apple forests, confirming a new host for these pathogens in this study. [ABSTRACT FROM AUTHOR]

In this study, we sequenced the mitochondrial (mt) genome of Agrilus mali (Coleoptera: Buprestidae) using next-generation sequencing, and accordingly annotated 13 protein-coding, 22 tRNA, and 2 rRNA genes and a 1458-bp non-coding region. Comparative analysis indicated that the mt genome of A. mali is relatively conserved, with a typical gene content and order identical to those of other coleopterans. However, the newly sequenced mt genome is characterized by a relatively higher A + T content compared with that of other species within the family Buprestidae. Phylogenetic analysis based on Bayesian inference revealed that the evolutionary relationship among the six infraorders of the suborder Polyphaga is (Scirtiformia + (Elateriformia + ((Scarabaeiformia + Staphyliniformia) + (Bostrichiformia + (Cucujiformia))))). However, the topology indicated that the family Buprestidae is a sister group to other Polyphaga infraorders, excluding Scirtiformia as a monophyly, and thus the monophyly of Elateriformia was not supported. This study not only presents the mt genome of a species in the family Buprestidae and a comparative analysis of jewel beetles but also examines the contribution of mt genomes in elucidating phylogenetic relationships within the suborder Polyphaga of Coleoptera. [ABSTRACT FROM AUTHOR]

The ideal mapping geometry in a Fizeau interferometer is to map equal height increments on a flat object and equal angle increments on a spherical surface to equal heights on the detector. So the initial intent of the optical design of Fizeau transmission spheres (TSs) is to provide R-θ mapping geometry for equal angle increments. The corresponding unequal heights mapping will introduce retrace error as coma when linear carrier fringes exist. On the contrary, equal heights mapping with R-sin θ mapping geometry will avoid linear carrier fringes induced coma error. These two different mapping geometries conflict especially for the TS with a small f-number. In this paper, we will first explore the design and the performance of the f/0.75  TS according to the two different mapping geometries, and then evaluate the mapping geometry for the commercial ZYGO f/0.75  TS, and give some engineering notes for the designers, the metrologists, and the fabricators in the optical laboratory.

Microsatellite markers were developed for epidemiological studies on the black locust gall midge Obolodiplosis robiniae (Haldeman) (Diptera: Cecidomyiidae), a native North America pest introduced to Europe and Asia. Polymorphism at each locus was tested on 68 individuals from six populations reared from infected host leaves of Robinia pseudoacacia L. collected in China. Fourteen loci were found to be polymorphic, with the number of alleles ranging from 3 to 10. The observed heterozygosity varied evenly from 0.2667 to 0.6540. For populations, the observed heterozygosity ranged from 0.1429 to 1.000. The allele frequency of the predominant allele varied from 0.250 to 0.500. All loci with negative FST values indicated heterozygote excess in each locus with six populations. Of 14 loci, four were observed to have FST values up to 0.05, which indicated negligible genetic differentiation within the population. Significant deviations (P < 0.05) from the expected Hardy-Weinberg equilibrium, as evaluated using the Markov chain algorithm for each locus and for all six populations, were observed, and genotypic linkage disequilibrium was clearly detected. These markers represent a useful tool to design strategies for integrated pest management and in the study of population evolution in this important introduced pest., (© The Author 2015. Published by Oxford University Press on behalf of the Entomological Society of America.)