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Nuclear pore complexes (NPCs) mediate the nucleocytoplasmic transport of macromolecules. Here we provide a structure of the isolated yeast NPC in which the inner ring is resolved by cryo-EM at sub-nanometer resolution to show how flexible connectors tie together different structural and functional layers. These connectors may be targets for phosphorylation and regulated disassembly in cells with an open mitosis. Moreover, some nucleoporin pairs and transport factors have similar interaction motifs, which suggests an evolutionary and mechanistic link between assembly and transport. We provide evidence for three major NPC variants that may foreshadow functional specializations at the nuclear periphery. Cryo-electron tomography extended these studies, providing a model of the in situ NPC with a radially expanded inner ring. Our comprehensive model reveals features of the nuclear basket and central transporter, suggests a role for the lumenal Pom152 ring in restricting dilation, and highlights structural plasticity that may be required for transport.

With the development of advanced aviation engines in the direction of high thrust-to-weight ratio and lightweight, a series of lightweight aviation materials such as titanium alloys, nickel-based high-temperature alloys, and ceramic-based composite materials have emerged and been widely used for the key components in the aerospace field, and have also become the main production materials for aero-engine blades. However, due to the stress concentration sensitivity of carbide and the anisotropy and brittle mechanism of composite materials, the fatigue failure problem is gradually highlighted. Existing studies show that the fatigue resistance performance of aero-engine blades has important relationship with its processing process, which in turn affects the service performance and service life of the equipment. Grinding, as the final material removal process for aero-engine blades, directly determines the final surface integrity and fatigue resistance of the blades while obtaining precise profiles. In order to understand the characteristics of blades processed by new lightweight aviation materials, and provide guidance for the processing of aero-engine blades for optimization of fatigue performance, the application of typical aero-engine blade materials and the research status of anti-fatigue grinding technology are summarized. Firstly, the characteristics of typical lightweight and high-strength aeronautical materials and their application in the production of aero-engine blades are briefly described. Secondly, the method of high surface integrity grinding and the key technology of anti-fatigue processing of aero-engine blades are analyzed. Finally, the research on anti-fatigue grinding of aero-engine blades is prospected.

Seawater intrusion has a significant impact on the irrigation quality of agricultural water, thereby posing a threat to plant growth and development. We hypothesized that the rhizosphere of tea plants harbors beneficial microorganisms, which may improve the tolerance of tea plants to seawater stress. This study utilized 16s and ITS techniques to analyze microbial community shifts in the tea plant rhizosphere and non-rhizosphere under seawater stress conditions. The findings suggest that seawater stress leads to a reduction in microbial diversity, although the rhizosphere microbial diversity in stressed soils showed a relatively higher level. Moreover, the rhizosphere of the tea plant under seawater stress exhibited an enrichment of plant growth-promoting rhizobacteria alongside a higher presence of pathogenic fungi. Network analysis revealed that seawater stress resulted in the construction of a more complex and stable rhizosphere microbial network compared to normal conditions. Predictions of bacterial potential functions highlighted a greater diversity of functional groups, enhancing resource utilization efficiency. In general, the rhizosphere microorganisms of tea plants are jointly selected by seawater and the host. The microorganisms closely related to the rhizosphere of tea plants are retained and, at the same time, attract beneficial microorganisms that may alleviate stress. These findings provide new insights into plant responses to saline stress and have significant implications for leveraging vegetation to enhance the resilience of coastal saline soils and contribute to economic progress. [ABSTRACT FROM AUTHOR]

Sauropus androgynus (S. androgynus) (2n = 4x = 52) is one of the most popular functional leafy vegetables in South and Southeast Asia. With its rich nutritional and pharmaceutical values, it has traditionally had widespread use for dietary and herbal purposes. Here, the genome of S. androgynus was sequenced and assembled, revealing a genome size of 1.55 Gb with 26 pseudo-chromosomes. Phylogenetic analysis traced back the divergence of Sauropus from Phyllanthus to approximately 29.67 million years ago (Mya). Genome analysis revealed that S. androgynus polyploidized around 20.51 Mya and shared a γ event about 132.95 Mya. Gene function analysis suggested that the expansion of pathways related to phloem development, lignin biosynthesis, and photosynthesis tended to result in the morphological differences among species within the Phyllanthaceae family, characterized by varying ploidy levels. The high accumulation of ascorbic acid in S. androgynus was attributed to the high expression of genes associated with the L-galactose pathway and recycling pathway. Moreover, the expanded gene families of S. androgynus exhibited multiple biochemical pathways associated with its comprehensive pharmacological activity, geographic adaptation and distinctive pleasurable flavor. Altogether, our findings represent a crucial genomic asset for S. androgynus, casting light on the intricate ploidy within the Phyllanthaceae family. [ABSTRACT FROM AUTHOR]

In order to realize ankle recovery,a kind of auxiliary device for ankle rehabilitation based on a ball pair is developed. The device adopts the center ball pair as the support,and 3S’PS’ branch chain as drive system,the three-dimensional motion of the working platform can be formed,and the dorsal flexion/plantar flexion movement,varus/valgus movement and adduction/abduction movement can be realized for ankle. Based on introducing the structure of the rehabilitation device,an inverse kinematic modeling and analysis for the device are performed. Arming at the multiple kind of movement patterns of system,an inverse kinematic modeling and analysis are completed respectively. The related calculation formulas are deduced and relation charts of motion angle between working platform and motor are plotted by using the Matlab. The research process provides a reference for the mechanism analysis of similar structure.

In order to realize ankle joint auxiliary rehabilitation,a kind of auxiliary device for ankle joint rehabilitation based on center ball pair is developed. The device adopts the center ball pair as the support,and 3S’PS’ branch chain as drive system. The rehabilitation device can form the three-dimensional motions of the working platform,which can realize auxiliary rehabilitation for ankle joint. The configuration of the device is introduced in detail,and movement process for the working platform to realize any posture is analyzed for the device. The calculation formulas of displacement,velocity and acceleration are deduced. On the basis of this,the concrete examples of motion analysis for device satisfying the motion constraint condition are given respectively,the basis for the design of the device control system is provided. The research process provide a reference for the motion analysis of similar structures.