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Abstract Space-air-ground integrated networks comprise a multi-level heterogeneous integrated network that combines satellite-based, aerial, and terrestrial networks. With the increasing human exploration of space and growing demands for internet applications, space-air-ground integrated networks have gradually emerged as the direction for communication network development. These networks face various challenges such as extensive coverage, diverse communication node types, low-quality communication links, and simultaneous operation of multiple network protocols. However, the rapid development and widespread application of artificial intelligence and machine learning technologies in recent years have offered new perspectives and solutions for the communication architecture and routing algorithm research within space-air-ground integrated networks. In these networks, not all nodes can typically communicate directly with satellites; instead, a specific set of specialized communication nodes facilitates data communication between aerial and satellite networks due to their superior communication capabilities. Consequently, in contrast to traditional communication architectures, space-air-ground integrated networks, particularly in the terrestrial layer, often need to address challenges related to the diversity of communication node types and low-quality communication links. A well-designed routing approach becomes crucial in addressing these issues. Therefore, this paper proposes an AODV routing network protocol based on an improved ant colony algorithm (AC-AODV), specifically designed for the terrestrial layer within the space-air-ground integrated networks. By integrating information such as the type, energy, and location of communication nodes, this protocol aims to facilitate network communication. The objective is to guide information flow through nodes that are more suitable for communication, either by relaying communication or by connecting with satellites through specialized nodes. This approach alleviates the burden on ordinary nodes within the terrestrial communication network, thereby enhancing the overall network performance. In this protocol, specialized nodes hold a higher forwarding priority than regular nodes. When a source node needs to transmit data, it enters the route discovery phase, utilizing its own type, location, and energy information as heuristic data to calculate forwarding probabilities. Subsequently, it broadcasts route request (RREQ) messages to find the path. Upon receiving the RREQ message, the destination node sends an RREP message for updating information elements and selects the optimal path based on these information elements. Compared to AODV, AC-AODV shows significant improvements in performance metrics such as transmission latency, throughput, energy conversion rate, and packet loss rate.

Introduction: Allotetraploid upland cotton (Gossypium hirsutum L.) is native to the Mesoamerican and Caribbean regions, had been improved in the southern United States by the mid-eighteenth century, was then dispersed worldwide. However, a Hainan Island Native Cotton (HIC) has long been grown extensively on Hainan Island, China. Objectives: Explore HIC’s evolutionary relationship and genomic diversity with other tetraploid cottons, its origin and whether it was used for YAZHOUBU (Yazhou cloth, World Intangible Cultural Heritage) weaving, and the role of structural variations (SVs) in upland cotton domestication. Methods: We assembled a high-quality genome of one HIC plant. We performed phylogenetic analysis, divergence time estimation, principal component analysis and population differentiation estimation using cotton assemblies and/or resequencing data. SVs were detected by whole-genome comparison. A F2 population was used for linkage analysis and to study effects of SVs. Buoyancy and salt water tolerance tests for seeds were conducted. Results: We found that the HIC belongs to G. purpurascens. G. purpurascens is best classified as a primitive race of G. hirsutum. The potential for long range transoceanic dispersal of G. purpurascens seeds was proved. A set of SVs, selective sweep regions between G. hirsutum races and cultivars, and quantitative trait loci (QTLs) of eleven agronomic traits were obtained. SVs, especially large-scale SVs, were found to have important effects on cotton domestication and improvement. Of them, eight large-scale inversions strongly associated with yield and fiber quality have probably undergone artificial selection in domestication. Conclusion: G. purpurascens including HIC is a primitive race of G. hirsutum, probably disperse to Hainan from Central America by floating on ocean currents, may have been partly domesticated, planted and was likely used for YAZHOUBU weaving in Hainan much earlier than the Pre-Columbian period. SV plays an important role in cotton domestication and improvement.

Measuring pilot mental workload (MWL) is crucial for enhancing aviation safety. However, MWL is a multi-dimensional construct that could be affected by multiple factors. Particularly, in the context of a more automated cockpit setting, the traditional methods of assessing pilot MWL may face challenges. Heart rate variability (HRV) has emerged as a potential tool for detecting pilot MWL during real-flight operations. This review aims to investigate the relationship between HRV and pilot MWL and to assess the performance of machine-learning-based MWL detection systems using HRV parameters. A total of 29 relevant papers were extracted from three databases for review based on rigorous eligibility criteria. We observed significant variability across the reviewed studies, including study designs and measurement methods, as well as machine-learning techniques. Inconsistent results were observed regarding the differences in HRV measures between pilots under varying levels of MWL. Furthermore, for studies that developed HRV-based MWL detection systems, we examined the diverse model settings and discovered that several advanced techniques could be used to address specific challenges. This review serves as a practical guide for researchers and practitioners who are interested in employing HRV indicators for evaluating MWL and wish to incorporate cutting-edge techniques into their MWL measurement approaches.

Broomrape (Orobanche cumana) is one of the most important parasitic plants that drastically reduces sunflower yield. The majority of existing resistance varieties have become insufficient for crop protection. Breeding for broomrape resistance is regarded as the most effective and environmentally friendly control measure. In this paper, mapping of a resistance gene for broomrape races E was performed in a recombinant inbred line population by bulk segregate analyses (BSA) combined with genotyping by-sequencing technology. One QTL with resistance candidate genes was mapped on 5 ​kb interval location from 157,393,001 to 157,850,000 on chromosome 3, the other QTL was located at 5,000 bp interval location from 173,910,001 to 173,915,000 on chromosome 14. Genomic region on candidate interval of chromosome 3 revealed 6 genes with potential resistance for broomrape including transcription factor MYB1R1, Phylloplanin, histone-lysine N-methyltransferase, methylglutaconyl-CoA hydratase, fasciclin-like arabinogalactan protein and fatty acid dehydrogenase. Two resistant genes on candidate interval of chromosome 14 were discovered with potential resistance for broomrape, which were ABC transporter C family member and Ethylene-responsive transcription factor. These precise locations would be valuable for selecting resistant genotypes in future.

Dugesia japonica is an excellent animal model for studying the regeneration mechanism due to its characteristics of rapid regeneration and easy breeding. PacBio sequencing was performed on the intact planarians (In) and regenerating planarians of 1 day (1d), 3 days (3d), and 5 days (5d) after amputation. The aim of this study is to deeply profile the transcriptome of D. japonica and to evaluate its regenerate changes. Using robust statistical analysis, we identified 5931, 5115, and 4669 transcripts differentially expressed between 1d and In, 3d and In, 5d and In, respectively. A total of 63 key transcripts were screened from these DETs. These key transcripts enhance the expression in different regenerate stages respectively to regulate specific processes including signal transduction, mitosis, protein synthesis, transport and degradation, apoptosis, neural development, and energy cycling. Finally, according to the biological processes involved in these potential key transcripts, we propose a hypothesis of head regeneration model about D. japonica. In addition, the weighted gene co-expression network analysis provides a new way to screen key transcripts from large amounts of data. Together, these analyses identify a number of potential key regulators controlling proliferation, differentiation, apoptosis, and signal transduction. What’s more, this study provides a powerful data foundation for further research on planarians regeneration.

As wind power technologies become maturer, the monopile foundation of offshore wind turbine is widely used because of its simple structure, few occupied space and low cost. However, under severe sea conditions, the impact of nonlinear wave load applied against the monopile foundation on the system structure safety cannot be ignored. In this paper, the 5MW offshore wind turbine of the National Renewable Energy Laboratory (NREL) was taken as the research object, and the computational fluid analysis software ‘STARCCM +’ was used to study the hydrodynamic characteristics of the monopile foundation of the wind turbine under different wave parameters. This paper mainly analyzed the upper wave, pressure and wave forces around the monopile foundation of the wind turbine under the same period and different wave heights. And the wave force calculated by CFD was compared with the result based on potential flow theory. The research results showed that with the rise of wave height, the upper wave, pressure and wave force around the monopile foundation increase continuously, and the second-peak phenomenon appeared at some measuring points on the water surface of the monopile foundation. Because the CFD method considers the fluid viscosity and is more in line with the real sea conditions, it is more accurate to obtain wave forces based on this method.

Fusarium wilt (FW) is one of the most economically damaging cotton diseases worldwide, causing yellowing, wilting, defoliation, vascular tissue damage and ultimately death. Identification of molecular markers linked to FW genes is vital to incorporate resistance into elite cotton cultivars. An intraspecific F2 in Gossypium hirsutum L. was developed by crossing with a highly resistant cultivar Zhongmiansuo 35 (ZMS35) and a susceptible cultivar Junmian 1 to screen simple sequence repeats (SSRs) closely linked to the FW resistance gene. FW was identified in F2:3 families by evaluating seedling leaf symptoms and vascular tissue damage at plant maturity under natural field infection conditions over 2 years. The results showed that FW resistance segregated in a 3:1 ratio as a simple monogenic trait in F2:3 families. Molecular mapping identified a FW resistance gene closely linked with the SSR marker JESPR304−280 in chromosome D3(c17). We proposed to name this gene FW R. A composite interval mapping method detected four QTLs for FW resistance in Chr.A7(c7), D1(c15), D9(c23) and D3, respectively. Among them, one major QTL (LOD > 20) was tagged near marker JESPR304 within an interval of 0.06–0.2 cM, and explained over 52.5–60.9% of the total phenotypic variance. The data confirmed the existence of a major gene in Chr.D3. This is the first report of molecular mapping of a major gene contributing FW resistance in cotton. The present research therefore provides an opportunity to understand the genetic control of resistance to FW and conduct molecular marker-assisted selection breeding to develop FW resistant cultivars. [ABSTRACT FROM AUTHOR]

Aerosol retention occurs when it penetrates through micro-leakage paths within the containment after nuclear reactor accidents. Aerosol particles are deposited by mechanisms such as gravity sedimentation, Brownian diffusion, entrance effect, and turbulence deposition, and the deposition efficiency is affected by the carrier gas flow conditions. Therefore, it is necessary to study aerosol deposition characteristics within micro-leakage paths under laminar and turbulent flow regimes. In this work, an experimental facility consisting of two circuits was established for investigating the flow characteristics and aerosol deposition behaviors. In the flow test circuit, the flow resistance characteristics of air within the Re range of 40 to 3 600 are obtained by measuring the pressure differential and volume flow rate. In the aerosol test circuit, the penetration of aerosols is obtained by measuring the particle size distribution and concentration at the inlet and outlet of the micro-leakage paths. The experimental configuration encompassed the use of capillaries with diameters of 350, 550, 800, and 1 000 μm and length of 52 mm, as well as a rectangular micro-channel with dimensions of 26 μm×30 mm×52 mm to simulate micro-leakage paths. The aerosol comprises polydisperse TiO2 dust particles with a mass median diameter of less than 1 μm. The results of the flow testing reveal that, in both capillaries and rectangular micro-channel, the variation curve of the Cd·Re (Cd is Darcy resistance coefficient) with Re significantly deviates from the traditional laminar characteristic curve within a range of ±5% when the Re reaches 700, indicating that the gas flow has transitioned into turbulent flow. Under laminar flow conditions, it is observed that within capillaries with diameters of 800 and 1 000 μm, aerosol deposition is not evident at Re ranging from 380 to 600. The particle size distributions at the inlet and outlet are similar, with the penetration exceeding 90%. However, within rectangular micro-channels at Re between 40 and 130, as the Re increases, the aerosol penetration increases from 12% to 50%. During to the differences in size and structure feature, rectangular micro-channel has an obvious entrance effect compared with thin wall capillary. With the increase of the Re, the lift force of particles generated by the entrance gas velocity gradient leads to a reduction in entrance deposition, so the penetration is enhanced. Under turbulent flow condition, it is observed that within capillaries with diameters of 350, 550, and 800 μm, the aerosol penetration shows a decreasing trend as Re increases from 800 to 3 600. In the test with capillary diameter of 550 μm and Re of 2 100, the proportion of larger particles shows significantly reduced. Aerosol deposition predominantly occurs within the vortex diffusion-impaction region and the inertia-dominated region, with the effect of turbulent eddies, the fluctuating velocity of particles towards the wall intensifies, accelerating the deposition of aerosols.