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With the increasing number of multi runway airports in China,it is of great significance to study the optimal design and evaluation method of taxiway operation scheme in maneuvering area of multi runway airport for promoting the intensive and efficient utilization of airport surface resources.The“fixed,one-way,forward and circular”,which is the design principle of taxiway operation scheme in maneuvering area of multi runway airport is given,as well as the design paradigm of“one-sided operation”and“two-sided operation”taxiway operation scheme for isolated operation scenario of parallel runway;Based on the“flight alternative taxiing path library”and the given basic principles and paradigms of taxiway operation scheme design,it is comprehensively working out to optimize the taxiway operation scheme in the maneuvering area.Taking Chengdu Tianfu International Airport as an example,three alternative operation schemes of taxiway in maneuvering area are designed,and AirTOp software is used for simulation and quantitative analysis for typical daily flight sorties.The results show that the design method of taxiway operation scheme in maneuvering area of multi runway airport is helpful to alleviate flight taxi delay,taxi conflict waiting time and taxi conflict proportion,The simulation evaluation method is suitable for the comparison and demonstration of surface operation schemes under large flight volume.

Simple Summary: The growth pattern of the Chinese soft-shelled turtle (Pelodiscus sinensis) is remarkably sexually dimorphic. However, the molecular mechanism of this phenomenon has been studied mainly in the gonadal tissues of P. sinensis, and no article has been published on the study of sex differentiation in the brain of P. sinensis. Here, we performed a whole transcriptome analysis of the brains of adult female and male P. sinensis. We obtained a set of differentially expressed genes and transcription factors, which we annotated with GO and KEGG, and screened some genes and pathways related to growth. In addition, through GESA analysis, we screened out two genes, LHX1 and FGF7, which are related to both growth and sex differentiation, and through protein interaction analysis of these genes, we screened out eight genes and verified the expression levels of these eight genes in the brain of P. sinensis by qRT-PCR, which supported the reliability and accuracy of our transcriptome analysis. This study provides a solid foundation for analyzing the growth mechanism of sexual dimorphism in P. sinensis and even other turtles. The Chinese soft-shelled turtle (Pelodiscus sinensis) is an economically important species in aquaculture, and its growth pattern is characterized by significant sexual dimorphism. However, the underlying molecular mechanisms of this phenomenon have mostly been investigated in the gonadal tissues of P. sinensis, and there are no articles on sex differentiation from the brain of P. sinensis. Here, we analyzed transcriptomes of the brains of adult male and female P. sinensis using high-throughput Illumina sequencing technology, establishing a set of differential genes and differential transcription factors. The data showed that there were 908 genes with significant differences in expression, of which 357 genes were up-regulated and 551 genes were down-regulated. We annotated using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG), and screened some genes and pathways related to growth. There were 282 growth-related differential genes and 181 sex-related differential genes. We screened the genes' growth hormone receptor (GHR) and vascular endothelial growth factor A (VEGFA), which may be related to the growth of P. sinensis. The pathways related to the growth and development of P. sinensis are the growth hormone synthesis, secretion, and action pathway; the MAPK (mitogen-activated protein kinase) pathway; and the calcium signaling pathway. In addition, through gene set enrichment analysis (GSEA), we screened out two genes, LIM homeobox protein 1 (LHX1) and fibroblast growth factor 7 (FGF7), which are related to both growth and sex differentiation, and through protein interaction analysis of these genes, we screened out eight genes, including LHX1, FGF7, GHR, fibroblast growth factor 4 (FGF4), EGFR, BMP3, GLI family zinc finger 2 (GLI2), and neuronal differentiation 1 (NEUROD1), and verified the expression levels of these eight genes in the brain of the P. sinensis by real-time quantitative PCR (qRT-PCR), which supported the reliability and accuracy of our transcriptome analysis. Our study provides a solid foundation for analyzing the mechanisms of sexual-dimorphic growth of P. sinensis and even other turtles. [ABSTRACT FROM AUTHOR]

The Northern snakehead (Channa argus) is a significant economic aquaculture species in China. Exhibiting sexual dimorphism in the growth rate between females and males, mono-sex breeding holds substantial value for aquaculture. This study employed GWAS and transcriptome analysis were applied to identify sex determination genomic regions and develop sex-specific markers. A total of 270 single-nucleotide polymorphisms (SNPs) and 31 insertion-deletions (InDels) were identified as being sexually dimorphic through GWAS and fixation index (Fst) scanning. Based on GWAS results, two sex-specific InDel markers were developed, effectively distinguishing genetic sex for XX females, XY males, and YY super-males via (polymerase chain reaction) PCR amplification. A major genomic segment of approximately 115 kb on chromosome 3 (Chr 03) was identified as the sex-determination region. A comparative transcriptome analysis of gonads for three sexes identified 158 overlapping differentially expressed genes (DEGs). Additionally, three sex-related candidate genes were identified near the sex determination region, including id2, sox11, and rnf144a. Further studies are required to elucidate the functions of these genes. Overall, two sex-specific InDel markers support a male heterogametic XX/XY sex-determination system in Northern snakeheads and three candidate genes offer new insights into sex determination and the evolution of sex chromosomes in teleost fish. [ABSTRACT FROM AUTHOR]

Magnetic soft continuum robots (MSCRs) hold significant potential in fulfilling the requirements of vascular interventional robots, enabling safe access to difficult-to-reach areas with enhanced active maneuverability, shape morphing capabilities, and stiffness variability. Their primary advantage lies in their tether-less actuation mechanism that can safely adapt to complex vessel structures. Existing commercial MSCRs primarily employ a magnetic-pull strategy, which suffers from insufficient driving force and a single actuation strategy, limiting their clinical applicability. Inspired by the inchworm crawling locomotion gait, we herein present a novel MSCR that integrates a magnetic sinusoidal actuation mechanism with adjustable frequency and kirigami structures. The developed MSCRs consist of two permanent magnets connected by a micro-spring, which is coated with a silicone membrane featuring a specific notch array. This design enables bio-inspired crawling with controllable velocity and active maneuverability. An analytical model of the magnetic torque and finite element analysis (FEA) simulations of the MSCRs has been constructed. Additionally, the prototype has been validated through two-dimensional in-vitro tracking experiments with actuation frequencies ranging from 1 to 10 Hz. Its stride efficiency has also been verified in a three-dimensional (3D) coronary artery phantom. Diametrically magnetized spherical chain tip enhances active steerability. Kirigami skin is coated over the novel guidewire and catheter, not only providing proximal anchorage for improved stride efficiency but also serving similar function as a cutting balloon. Under the actuation of an external magnetic field, the proposed MSCRs demonstrate the ability to traverse bifurcations and tortuous paths, indicating their potential for dexterous flexibility in pathological vessels. [ABSTRACT FROM AUTHOR]

With the increasingly busy operation of civil aviation airspace,how to build an effective and reasonable mathematical model from the perspective of quantitative analysis to quantify the risk of route flight collision and improve the scientific nature of route planning and management is a problem faced by the industry. A risk assessment method of vertical collision during route flight based on improved Event model is proposed. In this method,the cuboid collision box in the original event model is replaced by two spliced elliptic cone collision boxes which conform to the velocity vector distribution of the aircraft in space to calculate the probability of the aircraft passing through the adjacent altitude layers. The vertical collision risk formula of the aircraft in the improved route is derived by using the area size ratio of the improved front and rear collision boxes. The collision risk parameters obtained by formula are verified. The results show that the vertical collision risk calculated by the improved method is about 13% of the original cuboid event model and 67% of the original ellipsoid event model. It is feasible to use this method for quantitative evaluation.

Current research on apron conflict detection is often limited to the interaction between the aircraft as a whole and other objects, making it difficult to accomplish targeted identification of vulnerable and high‐cost aircraft components. However, the implementation of detailed aircraft identification is of great significance to enhance the safety of airport surface operations. Based on the excellent performance of High‐Resolution Network (HRNet) in keypoint detection, a lightweight end‐to‐end keypoint detection network, namely Squeeze and Excitation High‐Resolution Network (SEHRNet), is proposed in this paper to solve the problems of HRNet's slower computation and more redundancy. First, the errors arising from coordinate transformations in the coding and decoding process are solved by an improved feature map coding and decoding process. Second, replace the BasicBlock in HRNet with the Depthwise separable convolutions based on the Squeeze‐and‐Excitation Networks, which drastically cuts the computational cost of the network. Third, the improved Bottleneck module is used to further enhance the capability of feature extraction. Experimental results prove that, based on the aircraft keypoint detection dataset, the SEHRNet proposed in this paper shows stronger applicability compared to the current mainstream networks. Compared with the original HRNet, the improved network has higher accuracy, faster speed, and lighter model for aircraft keypoint detection. [ABSTRACT FROM AUTHOR]

In this paper, a data-driven framework aimed at investigating how weather factors affect the spatio-temporal patterns of air traffic flow in the terminal maneuvering area (TMA) is presented. The framework mainly consists of three core modules, namely, trajectory structure characterization, flow pattern recognition, and association rule mining. To fully characterize trajectory structure, abnormal trajectories and typical operations are sequentially extracted based on a deep autoencoder network with two specially designed loss functions. Then, using these extracted elements as basic components to further construct and cluster per-hour-level descriptions of airspace structure, the spatio-temporal patterns of air traffic flow can be recognized. Finally, the association rule mining technique is applied to find sets of weather factors that often appear together with each flow pattern. Experimental analysis is demonstrated on two months of arrival flight trajectories at Hong Kong International Airport (HKIA). The results clearly show that the proposed framework effectively captures spatial anomalies, fine-grained trajectory structures, and representative flow patterns. More importantly, it also reveals that those flow patterns with non-conforming behaviors result from complex interactions of various weather factors. The findings provide valuable insights into the causal relationships between weather factors and changes in flow patterns, greatly enhancing the situational awareness of TMA. [ABSTRACT FROM AUTHOR]

Narrow-headed softshell turtles constitute a group of critically endangered freshwater turtles that belong to the family Trionychidae. Here, we determine the complete mitogenome of the Burmese narrow-headed softshell turtle Chitra vandijki. The length of the mitochondrial genome was 16,614 bp, composed of 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and twelve noncoding regions. The phylogenetic analysis strongly indicated that C. vandijki is closely related to C. indica. The mitochondrial genome will contribute to the genetic research and conservation of C. vandijki in the future.

Rheumatoid arthritis (RA) is an autoimmune disease that significantly impacts quality of life by disrupting CD4+ T cell immune homeostasis. The identification of a low-side-effect drug for RA treatment is urgently needed. Our previous study suggests that Trichinella spiralis paramyosin (Ts-Pmy) has immunomodulatory effects, but its potential effect on CD4+ T cell response in RA remains unclear. In this study, we used a murine model to investigate the role of rTs-Pmy in regulating CD4+ T cell differentiation in collagen-induced arthritis (CIA). Additionally, we assessed the impact of rTs-Pmy on CD4+ T cell differentiation towards the Th1 and Th17 phenotypes, which are associated with inflammatory responses in arthritis, using in vitro assays. The results demonstrated that rTs-Pmy administration reduced arthritis severity by inhibiting Th1 and Th17 response while enhancing Treg response. Prophylactic administration of Ts-Pmy showed superior efficacy on CIA compared to therapeutic administration. Furthermore, in vitro assays demonstrated that rTs-Pmy could inhibit the differentiation of CD4+ T cells into Th1 and Th17 while inducing the production of Tregs, suggesting a potential mechanism underlying its therapeutic effects. This study suggests that Ts-Pmy may ameliorate CIA by restoring the immune balance of CD4+ T cells and provides new insights into the mechanism through which helminth-derived proteins exert their effects on autoimmune diseases. [ABSTRACT FROM AUTHOR]

To adapt to the intelligent management of traffic flow in modern aviation, this study improves the algorithm according to the data exercise method and establishes the mathematical model and vector model of intelligent motion coordinates. Moreover, according to the simulation test method, this study analyzes the six-degree-of-freedom equation of motion in the coordinate system of the civil aviation aircraft and uses the simulation method to regard the civil aviation as a rigid body with a certain mass and mass distribution. In addition, this study builds an intelligent model based on the demand analysis, and according to the actual demand, this study combines the simulation method to analyze the structure of the intelligent management model of air traffic flow. Finally, this study uses the experimental analysis method to verify the effect of the model proposed in this study and combines the experimental research to verify that the model proposed in this study has a certain effect., Author(s): Junhao Liu (corresponding author) [1]; Qing Cheng [1]; Yuanji Wang [1]; Changqi Yang [1]; Rui Zhou [1]; Xinping Zhu [1]; Di Yao [1]; Junjie Zhou [1]; Yaqian Du [1]; [...]