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Facing the challenges of in-situ utilization of lunar regolith resources, applying an external electric field to manipulate lunar particles has become a promising method for space particle control, which mainly depends on the particle charging properties in the applied electric field. Using the surficial lunar regolith samples brought back from the Moon by the Chang’e-5 mission (CE5 LS), this work successively studied their charging properties, particle dynamics, and their collision damages to aerospace materials under the action of an external electric field in high-vacuum conditions. The results indicated that the charging process and electrostatic projection of lunar regolith particles under high-vacuum conditions were different from those under atmosphere conditions. The particle diameter range of CE5 LS used in the experiment is 27.7–139.0 μm. For electric field strength of 3–12 kV·cm−1, the charge obtained by CE5 LS is 4.8 × 10−15–4.7 × 10−13 C and the charge-to-mass ratio is 1.2 × 10−5–6.8 × 10−4 C·kg−1. The CE5 LS is easier to be negatively charged in an external electric field. Furthermore, significant damages were observed on the target impact surfaces, indicating severe influences of lunar regolith particles on aerospace materials. Our work contributes to a more comprehensive understanding of physical mechanisms controlling the lunar regolith shielding and utilization, and will inspire broad efforts to develop the lunar in-situ engineering solutions.

Finding water resources is a crucial objective of lunar missions. However, both hydroxyl (OH) and natural water (H2O) have been reported to be scarce on the Moon. We propose a potential method for obtaining water on the Moon through H2O formation via endogenous reactions in lunar regolith (LR), specifically through the reaction FeO/Fe2O3 + H → Fe + H2O. This process is demonstrated using LR samples brought back by the Chang’E-5 mission. FeO and Fe2O3 are lunar minerals containing Fe oxides. Hydrogen (H) retained in lunar minerals from the solar wind can be used to produce water. The results of this study reveal that 51–76 mg of H2O can be generated from 1 g of LR after melting at temperatures above 1,200 K. This amount is ∼10,000 times the naturally occurring OH and H2O on the Moon. Among the five primary minerals in LR returned by the Chang’E-5 mission, FeTiO3 ilmenite contains the highest amount of H, owing to its unique lattice structure with sub-nanometer tunnels. For the first time, in situ heating experiments using a transmission electron microscope reveal the concurrent formation of Fe crystals and H2O bubbles. Electron irradiation promotes the endogenous redox reaction, which is helpful for understanding the distribution of OH on the Moon. Our findings suggest that the hydrogen retained in LR is a significant resource for obtaining H2O on the Moon, which is helpful for establishing a scientific research station on the Moon.

The stem tips of Zizania latifolia at different development stages were used as research materials. The expression stability of nine candidate reference genes (ACT1, H2B, UBI, EF-1α, GAPDH, β-actin, 60S, SKIP and AQP) were evaluated using qRT-PCR. The data were analyzed with GeNorm and NormFinder software. Present results indicated that the expression of ACT1 was stable and that it could be used as the optimal reference gene for studying the development stage of gall formation. ACT1 was selected as the reference gene to verify the expression level of the correlative genes in the gall formation stage of Z. latifolia. Our results were consistent with the previous transcriptome sequencing results. This study revealed that ACT1 was the classic reference gene for the analysis of correlative genes in all of the gall development stages of Z. latifolia.

Melting and solidification of lunar regolith are pivotal for comprehending the evolutionary dynamics of lunar volcanism, geology, and impact history. Additionally, insights gained from these processes can contribute to the advancement of in situ resource utilization technologies, for instance additive manufacturing and resource extraction systems. Herein, we conduct the direct observation of the melting and rapid solidification of lunar particles returned by the Chang’E 5 mission. The melting temperature and melting sequence were obtained. Bubble generation, growth, and release were clearly observed, with a maximum bubble diameter of 5 µm, which is supposed to be according to the release of volatiles that embedded in the particles. During the solidification process, evident crystallization occurred with incremental crystal growth rate approximately of 27 nm/s. Scanning electron microscopy and energy-dispersive x-ray spectroscopy results verified that the Fe-rich mineral crystalizes first. These results would improve the understanding of the evolution of lunar volcanism, geology, and impact history.

ObjectiveTo promote the development and therapeutic application of new medications, it is crucial to conduct a thorough investigation into the mechanism by which the traditional Chinese herb pair of Haizao-Kunbu (HK) treats Graves’ disease (GD).Materials and methodsChemical ingredients of HK, putative target genes, and GD-associated genes were retrieved from online public databases. Using Cytoscape 3.9.1, a compound-gene target network was established to explore the association between prosperous ingredients and targets. STRING, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes pathway analyses visualized core targets and disease pathways. Additionally, we conducted a refined analysis of the binding interactions between active ingredients and their respective targets. To visualize these findings, we employed precise molecular docking techniques. Furthermore, we carried out molecular dynamics simulations to gain insights into the formation of more tightly bound complexes.ResultsWe found that there were nine key active ingredients in HK, which mainly acted on 21 targets. These targets primarily regulated several biological processes such as cell population proliferation, protein phosphorylation, and regulation of kinase activity, and acted on PI3K-AKT and MAPK pathways to treat GD. Analysis of the molecular interaction simulation under computer technology revealed that the key targets exhibited strong binding activity to active ingredients, and Fucosterol-AKT1 and Isofucosterol-AKT1 complexes were highly stable in humans.ConclusionThis study demonstrates that HK exerts therapeutic effects on GD in a multi-component, multi-target, and multi-pathway manner by regulating cell proliferation, differentiation, inflammation, and immunomodulatory-related targets. This study provides a theoretical foundation for further investigation into GD.

Smut fungi display a uniform life cycle including two phases: a saprophytic phase in vitro and a parasitic phase in host plants. Several apathogenic smut fungi are found, lacking suitable hosts in their habitat. Interestingly, MT-type Ustilago esculenta was found to maintain a parasitic life, lacking the saprophytic phase. Its long period of asexual proliferation in plant tissue results in severe defects in certain functions. In this study, the growth dynamics of U. esculenta in plant tissues were carefully observed. The mycelia of T- and MT-type U. esculenta exhibit rapid growth after karyogamy and aggregate between cells. While T-type U. esculenta successfully forms teliospores after aggregation, the aggregated mycelia of MT-type U. esculenta gradually disappeared after a short period of massive proliferation. It may be resulted by the lack of nutrition such as glucose and sucrose. After overwintering, infected Zizania latifolia plants no longer contained diploid mycelia resulting from karyogamy. This indicated that diploid mycelia failed to survive in plant tissues. It seems that diploid mycelium only serves to generate teliospores. Notably, MT-type U. esculenta keeps the normal function of karyogamy, though it is not necessary for its asexual life in plant tissue. Further investigations are required to uncover the underlying mechanism, which would improve our understanding of the life cycle of smut fungi and help the breeding of Z. latifolia.

Zizania latifolia (Z. latifolia) is a popular aquatic vegetable with various nutrients in south China, but little is known about its cultivars and growing seasons in terms of the nutritional components. This work aims to characterize the nutrients of five Z. latifolia cultivars in different growing seasons. The results showed that Z. latifolia samples differed in terms of chemical parameters, which were significantly affected by variety, growing season, and their interaction. Zhejiao No. 8, harvested in the autumn, stood out with the highest levels of vitamin C. Tangxiajiao and Zhejiao No. 1 contained the highest values of total soluble solids, reducing sugar, soluble proteins, and amino acids. Significant differences were observed between the autumn Z. latifolia and spring samples; the former were of higher quality than the latter based on hierarchical clustering analysis and principal component analysis. Moreover, total amino acids (TAA) and glutamic acid (GLU) were selected as the key indicators for Z. latifolia comprehensive quality by multiple linear regression analysis. This study provides essential information on Z. latifolia quality characteristics corresponding to cultivars and growing seasons, which lays the foundation for promoting the quality improvement of Z. latifolia scientifically.

The Zizania latifolia is usually infected by the obligate parasitic fungus Ustilago esculenta to form an edible fleshy stem which is an aquatic vegetable called Jiaobai in China. The infection by the teliospore (T) strain of U. esculenta induces Z. latifolia forming gray fleshy stems, while the mycelia-teliospore (MT) strain of U. esculenta induces white fleshy stems which are more suitable for edibility than gray fleshy stems. The mechanism of this phenomenon is still largely unknown. One of the possible causes is the diversity of endophytic microbial communities between these two fleshy stems. Therefore, we utilized fungal ITS1 and bacterial 16S rDNA amplicon sequencing to investigate the diversity of endophytic microbial communities in the two different fleshy stems of Z. latifolia. The results revealed that the α diversity and richness of endophytic fungi in white Z. latifolia were significantly greater than in gray Z. latifolia. The dominant fungal genus in both fleshy stems was U. esculenta, which accounted for over 90% of the endophytic fungi. The community composition of endophytic fungi in gray and white Z. latifolia was different except for U. esculenta, and a negative correlation was observed between U. esculenta and other endophytic fungi. In addition, the dominant bacterial genus in gray Z. latifolia was Alcaligenaceae which is also negatively correlated with other bacterium communities. Additionally, the co-occurrence network of white Z. latifolia was found to have a stronger scale, connectivity, and complexity compared to that of gray Z. latifolia. And the detected beneficial bacteria and pathogens in the stems of Z. latifolia potentially compete for resources. Furthermore, the function of endophytic bacteria is more abundant than endophytic fungi in Z. latifolia. This research investigated the correlation between the development of Z. latifolia fleshy stems and endophytic microbial communities. Our findings indicate that the composition of endophytic microbial communities is closely related to the type of Z. latifolia fleshy stems. This research also suggests the potential utilization of specific microbial communities to enhance the growth and development of Z. latifolia, thereby contributing to the breeding of Z. latifolia.

Due to low runtime overhead and simple implementation of DM (Deadline Monotonic) scheduling, it is widely used in real-time systems. Aiming at the schedulability test problem of the sporadic task DM scheduling under uniprocessor, a density upper bound of 0.693 is analyzed, which can determine the schedulability of a task set in linear time. The theoretical analysis process is carried out in three steps. Firstly, the case is considered where the task set contains only two tasks and the deadline ratio between the tasks is less than 2. Secondly, the case is considered where the task set contains multiple tasks and the deadline ratio between any two tasks is still less than 2. Finally, the case is considered where the task set contains multiple tasks and the deadline ratio between tasks is an arbitrary value. The experimental results show that the upper bound of density is higher than related methods and the run time overhead is much lower than that of other available exact schedulability tests. The time complexity is $O(1)$ when a task is dynamically added to a task set, while that of other methods increases rapidly along with the number of tasks. In addition, we combined this upper bound and other tests to further propose an exact schedulability test, which effectively reduces the running time overhead by 30.8% compared with the state-of-the-art schedulability test. Due to the high efficiency of our schedulability test, an online schedulability test can be implemented in open real-time systems.

Abstract Background Ustilago esculenta, a typical dimorphic fungus could infect Zizania latifolia and induce host stem swollen to form an edible vegetable called Jiaobai in China. The strains differentiation especially in the mating ability and pathogenicity is closely related to different phenotypes of Jiaobai formed in the fields. Dimorphic switching, a tightly regulated processes, is essential for the pathogenetic development of dimorphic fungi. In responses to environment cues, dimorphic switching can be activated through two conserved cell signaling pathways-PKA and MAPK pathways. Previous study indicated that exogenous arginine could induce hyphal formation in several dimorphic fungi through hydrolysis by arginase, but inhibit the dimorphic transition of U. esculenta. We conducted this study to reveal the function of arginine on dimorphic transition of U. esculenta. Results In this study, we found that arginine, but not its anabolites, could slow down the dimorphic transition of U. esculenta proportionally to the concentration of arginine. Besides, UeArginase, predicated coding arginase in U. esculenta was cloned and characterized. UeArginase mutants could actually increase the content of endogenous arginine, and slow down the dimorphic transition on either nutritious rich or poor medium. Either adding exogenous arginine or UeArginase deletion lead to down regulated expressions of UePkaC, UePrf1, mfa1.2, mfa2.1, pra1 and pra2, along with an increased content of arginine during mating process. Conclusion Results of this study indicated a direct role of arginine itself on the inhibition of dimorphic transition of U. esculenta, independent of its hydrolysis by UeArginase.