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Ustilaginoidea virens is the causal agent of rice false smut, which can be a highly destructive disease of rice. The plasma membrane phosphatase Psr1 proteins, which act as a regulator of the salinity stress response in yeast, are widely distributed across fungi, but their functional characterization is sketchy. In this study, we characterized the functions of Psr1 protein, UvPsr1, in U. virens. Analyses of the ΔUvpsr1 and its complementation strain showed that UvPsr1 is required for normal mycelial growth, conidiation and tolerance to oxidative, osmotic and cell wall stresses. When rice panicles were inoculated with the ΔUvpsr1 strains, no symptoms of false smut disease developed, showing that UvPSR1 also contributes to the pathogenicity of the fungus. The deletion mutant of UvPSR1 also appeared to produce a smaller titer of toxic compounds able to inhibit elongation of the germinated seeds. In conclusion, our results indicated that UvPsr1 is a new pathogenic factor of U. virens.

Rice false smut disease, which is caused by the fungus Ustilaginoidea virens, is currently one of the most devastating rice fungal diseases in the world. Rice false smut disease not only causes severe yield loss and grain quality reduction, but also threatens food safety due to its production of mycotoxins. In this review, the most recent progresses regarding the life cycle, infection processes, genome and genetic diversity, pathogenic gene and disease resistance in rice were summarized in order to provide theoretical basis for the control of U. virens. We also proposed some future directions and key questions that need to be addressed for a better understanding of the molecular mechanism that leads to rice false smut disease and the prospects for sustainable control of rice false smut. Keywords: Ustilaginoidea virens, Rice false smut disease, Life cycle, Infection process, Pathogenesis gene, Disease resistance

The battery capacity of lithium battery will decay at low temperature, and the battery performance will seriously decline at extremely low temperature, and the electrolyte will also freeze. Therefore, lithium batteries need to be preheated at low temperature. This paper selects 22 Ah lithium iron phosphate battery as the research object. The preheating scheme of PTC aluminum plate heating plate for lithium battery was designed by thermal parameter calculation and simulation method. The preheating scheme was optimized by changing the number (2, 3 and 4 pieces) and size (120%, 80% and 60% lithium battery size) of PTC heating plate. The results show that when heating 6 pieces of 22 Ah lithium iron phosphate battery, the preheating effect of 3 pieces of PTC heating plate close to the size of lithium battery is the best.

Rapid fabricating and harnessing stimuli-responsive behaviors of microscale bio-compatible hydrogels are of great interest to the emerging micro-mechanics, drug delivery, artificial scaffolds, nano-robotics, and lab chips. Herein, we demonstrate a novel femtosecond laser additive manufacturing process with smart materials for soft interactive hydrogel micro-machines. Bio-compatible hyaluronic acid methacryloyl was polymerized with hydrophilic diacrylate into an absorbent hydrogel matrix under a tight topological control through a 532 nm green femtosecond laser beam. The proposed hetero-scanning strategy modifies the hierarchical polymeric degrees inside the hydrogel matrix, leading to a controllable surface tension mismatch. Strikingly, these programmable stimuli-responsive matrices mechanized hydrogels into robotic applications at the micro/nanoscale (

Understanding the hydrogen (H) capacity, which represents the tritium capacity in Li2TiO3 crystal has become an important aspect of the tritium release process of nuclear fusion. In this work, a systematic density-functional-theory (DFT) study is performed to investigate the trapping and accumulation of H in Li2TiO3 crystal. In perfect crystal, the H adsorption properties are investigated and the maximum number of trapped H atoms are obtained. In the defect models, by calculating the trapping energy and Bader charge, we find that a Li vacancy can capture four H atoms while the capacity of a Ti vacancy is seven and then other H atoms tend to be trapped by interstitial sites outside the vacancy. Then the H capacity both inside and outside the vacancy in the defect models is studied and analyzed. According to our calculations, crystals containing a vacancy present stronger H trapping abilities than perfect crystals, especially for the crystal with a Ti vacancy. In addition, the increase of H atoms in the vacancy facilitates the formation of the neighboring vacancy so that more H atoms can be accommodated in the crystal with vacancy. Our results reveal the H capacity of different Li2TiO3 models, which provide theoretical support for related tritium release experiments. [ABSTRACT FROM AUTHOR]

Employing traditional Galerkin method, a coupled-mode flutter is predicted in the supercritical region of simply-supported pipes which constitutes a paradox since the internal flow effect is conservative and there is no energy to sustain the oscillation. Although there is a consensus that the flutter does not exist, the intrinsic mechanism remains to be clarified. This study has found that the internal flow induced Coriolis force term cannot be decoupled in traditional Galerkin method which leads to the dissatisfaction of the convergence conditions required in weighted residual approach (WRA). Moreover, the disparities in the predicted complex frequencies have been witnessed at different base function numbers when the internal flow velocity is sufficiently large. A modified Galerkin method adopting a new set of weighting functions is proposed based on WRA, and the Coriolis force term disappears by use of the orthogonality relations (it is stated that the Coriolis force is not directly omitted). Thus, a convergent solution for the set of residual functions which are identically equal to zeros can be guaranteed. Employing the modified method, the convergence in simulations is confirmed and the flutter phenomenon does not occur. This study can be a workbench for the study on the unsolved or partly solved issues in simulations of fluid-conveying pipes. Moreover, it has demonstrated that the predictions in traditional Galerkin method overestimate the natural frequencies, and it becomes more profound in higher-order natural modes at larger internal flow velocities which are of practice significance for dynamic analysis of flexible pipeline systems. [ABSTRACT FROM AUTHOR]

Near-infrared laser radiation based on Nd3+-doped yttrium ortho-aluminate (Nd:YAlO3, Nd:YAP) has garnered significant interest regarding solid-state lasers. Nevertheless, the crystal microstructures and electronic characteristics of Nd:YAP are still unclear, and the unique physical properties underlying its enormous applications require clarification. In this study, we conducted first-principles calculations at the atomic level to explore the electronic properties and mechanical characteristics of both pure YAP and Nd3+-doped YAP. The results suggest that the substitution of the Y3+ ion site with the Nd3+ impurity ion induces slight structural distortion in the YAP crystal lattice. An impurity band emerges between the original conduction band and the valence band, attributed to the 4f orbital of the Nd3+ ion, exerting a substantial influence on the narrowing of the band gap. Through an analysis of the mechanical characteristics of both pure YAP and Nd:YAP, we conclude that the incorporation of Nd3+ atoms leads to a reduction in the mechanical properties of YAP to a certain extent. Our study can serve as a foundational data source for investigations into material performance, especially for the application of Nd:YAP in solid-state laser systems. [ABSTRACT FROM AUTHOR]