Detection Transformer with Multi-Scale Fusion Attention Mechanism for Aero-Engine Turbine Blade Cast Defect Detection Considering Comprehensive Features.

Casting defects in turbine blades can significantly reduce an aero-engine's service life and cause secondary damage to the blades when exposed to harsh environments. Therefore, casting defect detection plays a crucial role in enhancing aircraft performance. Existing defect detection methods face challenges in effectively detecting multi-scale defects and handling imbalanced datasets, leading to unsatisfactory defect detection results. In this work, a novel blade defect detection method is proposed. This method is based on a detection transformer with a multi-scale fusion attention mechanism, considering comprehensive features. Firstly, a novel joint data augmentation (JDA) method is constructed to alleviate the imbalanced dataset issue by effectively increasing the number of sample data. Then, an attention-based channel-adaptive weighting (ACAW) feature enhancement module is established to fully apply complementary information among different feature channels, and further refine feature representations. Consequently, a multi-scale feature fusion (MFF) module is proposed to integrate high-dimensional semantic information and low-level representation features, enhancing multi-scale defect detection precision. Moreover, R-Focal loss is developed in an MFF attention-based DEtection TRansformer (DETR) to further solve the issue of imbalanced datasets and accelerate model convergence using the random hyper-parameters search strategy. An aero-engine turbine blade defect X-ray (ATBDX) image dataset is applied to validate the proposed method. The comparative results demonstrate that this proposed method can effectively integrate multi-scale image features and enhance multi-scale defect detection precision.

Exercise is the dominant factor affecting the development of teenagers' eyesight-Based on the Bayesian model averaging.

Objective: The model uncertainty may result in inconsistency about the environmental factors of myopia among students, and the Bayesian model average (BMA) is an effective way to eliminate it. We aimed to explore the influencing factors of myopia in primary and middle school students by BMA. Methods: The data came from the 2021 National Surveillance of Common Diseases and Health Influencing Factors of students. By stratified random cluster sampling, the physical and mental health status of students in Tianjin and the factors affecting their physical health, such as diet, exercise, mental stress, school bullying, sleep time, and internet use, were investigated. The sample consisted of 8,457 primary school students, 8,191 junior middle school students, and 5,901 senior middle school students. Besides the physical examination, we used computer optometry (non-ciliary paralysis) to screen myopia. And we used BMA to select the risk factors through the BMS package in R. Results: The exercise was the only factor that affected the eyesight of junior and senior middle schoolers by BMA, with the posterior probability of 0.9736 and 0.9762, but not for the primary students. And we failed to select variables that affected eyesight in grades 4-6 of primary school. Conclusion: The exercise was a strong influencing factor for the eyesight of students in Tianjin's junior and senior middle schools.

cDNA isolation and functional characterization of UDP-glucose 4-epimerase from Davallia divaricate.

UDP-glucose 4-epimerase (UGE) is a universal enzyme responsible for interconversion of UDP-glucose and UDP-galactose. However, the gene encoding UGE from Davallia divaricate is elusive. In this study, two UGE genes, ddUGE1 and ddUGE2, were isolated and cloned from D. divaricate using a transcriptome-guided search strategy. Two unigenes sharing high sequence identity with UGE homologous genes were selected from transcriptome assembly. The enzymes, further functionally expressed in Escherichia coli, exhibit narrow substrate specificity. The biochemical characterization assays of DdUGE1 and DdUGE2 showed good thermal and pH stability, and metal ion independence, which provides a meaningful feature for biotechnological applications.[Formula: see text].

[Research progress in natural allopyranosides].

The pharmacological activities of natural glycosides are closely related to the polyfunctional sugar moieties. Modification of active natural products by glycosylation can change the stereochemical configuration, improve the solubility, tune up the activities and change pharmacokinetic properties for higher efficacy and better selectivity. Compared with the common D-glucose, D-allose, a C-3 epimer of D-glucose rarely exists in nature, but it plays an important role in food, health, medicine, and so on. It is not easily metabolized in the living organisms, but can be used as a safe and low-calorie sweetener. The natural allopyranosides are absolute conjugation forms which are same as other glucopyranosides and rhamnopyranosides with a broad array of biological activities. This article summarizes the major progresses made in phytochemistry and biological activity studies of these compounds. Structure-activity relationship analyses of partial anti-tumor and anti-diabetic allopyranosides were performed regarding the data reported in the literatures. These insights may provide a theoretical and experimental reference for the discovery of new drug and drug design based on allopyranosides.

Identification of Development and Pathogenicity Related Gene in Botrytis cinerea via Digital Gene Expression Profile.

BACKGROUND: Botrytis cinerea, a haploid Euascomycete fungus that infects numerous crops, has been used as a model system for studying molecular phytopathology. Botrytis cinerea adopts various modes of infection, which are mediated by a number of pathogenicity and virulence-related genes. Many of these genes have not been reported previously. OBJECTIVES: This study aimed to investigate development and pathogenicity-related genes between a novel nonpathogenic mutant and the Wild Type (WT) in B. cinerea. MATERIALS AND METHODS: Digital Gene Expression (DGE) tag profiling can reveal novel genes that may be involved in development and pathogenicity of plant pathogen. A large volume of B. cinerea tag-seq was generated to identify differential expressed genes by the Illumina DGE tag profiling technology. RESULTS: A total of 4,182,944 and 4,182,021 clean tags were obtained from the WT and a nonpathogenic mutant stain (BCt89), respectively, and 10,410 differentially expressed genes were identified. In addition, 84 genes were expressed in the WT only while 34 genes were expressed in the mutant only. A total of 664 differentially expressed genes were involved in 91 Kyoto Encyclopedia of Genes and Genome pathways, including signaling and metabolic pathways. CONCLUSIONS: Expression levels of 1,426 genes were significantly up-regulated in the mutant compared to WT. Furthermore, 301 genes were down-regulated with False Discovery Rates (FDR) of < 0.001 and absolute value of log2 Ratio of ≥ 1.

[Discussion on the botanical origin of Isatidis radix and Isatidis folium based on DNA barcoding].

This paper aimed to investigate the botanical origins of Isatidis Radix and Isatidis Folium, and clarify the confusion of its classification. The second internal transcribed spacer (ITS2) of ribosomal DNA, the chloroplast matK gene of 22 samples from some major production areas were amplified and sequenced. Sequence assembly and consensus sequence generation were performed using the CodonCode Aligner. Phylogenetic study was performed using MEGA 4.0 software in accordance with the Kimura 2-Parameter (K2P) model, and the phylogenetic tree was constructed using the neighbor-joining methods. The results showed that the length of ITS2 sequence of the botanical origins of Isatidis Radix and Isatidis Folium was 191 bp. The sequence showed that some samples had several SNP sites, and some samples had heterozygosis sites. In the NJ tree, based on ITS2 sequence, the studied samples were separated into two groups, and one of them was gathered with Isatis tinctoria L. The studied samples also were divided into two groups obviously based on the chloroplast matK gene. In conclusion, our results support that the botanical origins of Isatidis Radix and Isatidis Folium are Isatis indigotica Fortune, and Isatis indigotica and Isatis tinctoria are two distinct species. This study doesn't support the opinion about the combination of these two species in Flora of China.

[Studies on the leaf epidermal features of Lepidium (Brassicaceae) from China].

OBJECTIVE: Classification and diagnostic study on Lepidiumn (Brassicaceae) from China. METHODS: Leaf epidermal mi-cromophology of 10 species of Lepidium from China were observed by using LM (light microscope) and SEM (scaning electron microscope). RESULTS: The stomatal apparatuses present both on the adaxial epidermis and the abaxial epidermis. The type of stomatal apparatuses is mainly anisocytic, rarely anomocytic and only occasionally paracytic. The leaf epidermal cells of Lepidium are usually irregular or polygonal in shape. The patterns of anticlinal walls are straight, arched, sinuolate or sinuous. The leaf features of Lepidium have better consistency. The morphology of the upper epidermis and the lower epidermis is similar, and with simple trichomes or glabrous on the leaf surface. Under SEM observation, the inner margin of the outer stomatal rim is nearly smooth or sinuolate, and the cuticular membrane of the leaf epidermis is striate. The shapes of leaf epidermal cells, the patterns of anticlinal walls, the types of stomatal ap-paratuses, the stomatal index, the stomatal size and the characters of the cuticular membrane of the leaf epidermis have important reference for differentiating species of Lepidium. CONCLUSION: The leaf epidermal features can serve as a criterion of distinguishing species in the genus Lepidium (Brassicaceae) from China, and also provide new evidence for rational use and exploitation of medical resources in Lepidium.

[Spatial correlation between non-agricultural land expansion and soil quality in Suzhou City].

Based on the layer of non-agricultural land expansion interpreted from 4 Landsat TM images in 1984, 1995, 2000 and 2003 and the soil quality map, the patterns of non-agricultural land expansion occurring on soil quality levels in Suzhou City were analyzed. It was indicated that the non-agricultural land expansion happened mainly on the soils with high quality during 1984-2003. 90% of the expansion took place on the soils with moderately high quality (grade 2), and the next was those with high quality (grade 1). In the meanwhile, the expansion on the soils with moderate (grade 3) and low quality (grade 4) was only less than 1% of total area. From the viewpoint of soil quality, we should ponder more over the opinion on "dynamic balance of total amount of arable land between occupying and supplementing".