115 research outputs found

    A critical role of a plant-specific TFIIB-related protein, BRP1, in salicylic acid-mediated immune response

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    An integral part of plant immunity is transcription reprogramming by concerted action of specific transcription factors that activate or repress genes through recruitment or release of RNA polymerase II (Pol II). Pol II is assembled into Pol II holoenzyme at the promoters through association with a group of general transcription factors including transcription factor IIB (TFIIB) to activate transcription. Unlike other eukaryotic organisms, plants have a large family of TFIIB-related proteins with 15 members in Arabidopsis including several plant-specific TFIIB-related proteins (BRPs). Molecular genetic analysis has revealed important roles of some BRPs in plant reproductive processes. In this study, we report that Arabidopsis knockout mutants for BRP1, the founding member of the BRP protein family, were normal in growth and development, but were hypersusceptible to the bacterial pathogen Psuedomonas syringae. The enhanced susceptibility of the brp1 mutants was associated with reduced expression of salicylic acid (SA) biosynthetic gene ISOCHORISMATE SYNTHASE 1 (ICS1) and SA-responsive PATHOGENESIS-RELATED (PR) genes. Pathogen-induced SA accumulation was reduced in the brp1 mutants and exogenous SA rescued the brp1 mutants for resistance to the bacterial pathogen. In uninfected plants, BRP1 was primarily associated with the plastids but pathogen infection induced its accumulation in the nucleus. BRP1 acted as a transcription activator in plant cells and binded to the promoter of ICS1. These results collectively indicate that BRP1 is a functionally specialized transcription factor that increasingly accumulates in the nucleus in response to pathogen infection to promote defense gene expression

    TaCA: Upgrading Your Visual Foundation Model with Task-agnostic Compatible Adapter

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    Visual foundation models like CLIP excel in learning feature representations from extensive datasets through self-supervised methods, demonstrating remarkable transfer learning and generalization capabilities. A growing number of applications based on visual foundation models are emerging, including innovative solutions such as BLIP-2. These applications employ pre-trained CLIP models as upstream feature extractors and train various downstream modules to accomplish diverse tasks. In situations involving system upgrades that require updating the upstream foundation model, it becomes essential to re-train all downstream modules to adapt to the new foundation model, which is inflexible and inefficient. In this paper, we introduce a parameter-efficient and task-agnostic adapter, dubbed TaCA, that facilitates compatibility across distinct foundation models while ensuring enhanced performance for the new models. TaCA allows downstream applications to seamlessly integrate better-performing foundation models without necessitating retraining. We conduct extensive experimental validation of TaCA using different scales of models with up to one billion parameters on various tasks such as video-text retrieval, video recognition, and visual question answering. The results consistently demonstrate the emergent ability of TaCA on hot-plugging upgrades for visual foundation models. Codes and models will be available at https://github.com/TencentARC/TaCA

    Extremely large magnetoresistance in topologically trivial semimetal α\alpha-WP2_2

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    Extremely large magnetoresistance (XMR) was recently discovered in many non-magnetic materials, while its underlying mechanism remains poorly understood due to the complex electronic structure of these materials. Here, we report an investigation of the α\alpha-phase WP2_2, a topologically trivial semimetal with monoclinic crystal structure (C2/m), which contrasts to the recently discovered robust type-II Weyl semimetal phase in β\beta-WP2_2. We found that α\alpha-WP2_2 exhibits almost all the characteristics of XMR materials: the near-quadratic field dependence of MR, a field-induced up-turn in resistivity following by a plateau at low temperature, which can be understood by the compensation effect, and high mobility of carriers confirmed by our Hall effect measurements. It was also found that the normalized MRs under different magnetic fields has the same temperature dependence in α\alpha-WP2_2, the Kohler scaling law can describe the MR data in a wide temperature range, and there is no obvious change in the anisotropic parameter γ\gamma value with temperature. The resistance polar diagram has a peanut shape when field is rotated in ac\textit{ac} plane, which can be understood by the anisotropy of Fermi surface. These results indicate that both field-induced-gap and temperature-induced Lifshitz transition are not the origin of up-turn in resistivity in the α\alpha-WP2_2 semimetal. Our findings establish α\alpha-WP2_2 as a new reference material for exploring the XMR phenomena.Comment: 18 pages, 12 figure

    Janus fibrous membrane with enhanced air filtration performance and oneway water transport capability for advanced face mask filters

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    During the winter season, the discomfort of wearing face masks is exacerbated by the accumulation of exhaled moisture within the face mask, significantly impairing user comfort. Addressing this issue, our study focuses on the development of a high- performance air filtration material endowed with a one-way water transport function. Herein, we meticulously crafted four distinct electrospun Janus fibrous membranes and conducted a comprehensive evaluation of their filtration performance and on-way water transport capabilities. To substantiate our experimental findings, we also performed CFD simulations to access the simulated pressure drop and water penetration process of the fibrous membranes using the CFD method. These simulation results provided valuable insights into the practical performance of the fibrous membranes under varying conditions, offering a promising solution to enhance both filtration performance and functionality of filtration materials for face masks used in challenging environmental conditions

    Long-distance continuous-variable quantum key distribution over 202.81 km fiber

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    Quantum key distribution (QKD) provides secure keys resistant to code-breaking quantum computers. The continuous-variable version of QKD offers the advantages of higher secret key rates in metropolitan areas, as well as the use of standard telecom components that can operate at room temperature. However, the transmission distance of these systems (compared with discrete-variable systems) are currently limited and considered unsuitable for long-distance distribution. Herein, we report the experimental results of long distance continuous-variable QKD over 202.81 km of ultralow-loss optical fiber by suitably controlling the excess noise and employing highly-efficient reconciliation procedures. This record-breaking implementation of the continuous-variable QKD doubles the previous distance record and shows the road for long-distance and large-scale secure QKD using room-temperature standard telecom components

    Stability of layer-by-layer nanofiltration membranes in highly saline streams

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    Layer-by-layer (LBL) assembly is an essential method for the preparation of nanofiltration (NF) membranes, offering tunable charge and pore size, high water permeability, and good anti-fouling properties, making them highly suitable for resource recovery, seawater desalination, and other fields. Despite their advantages, LBL NF membranes suffer from salinity instability, limiting their use in highly saline streams. This perspective review provides a summary of the fundamental physical and chemical principles of LBL assembly related to the salinity stability of LBL NF membranes. We critically analyze the driving force of LBL assembly, the binding strength of polyelectrolyte (PE) pairs, and the overcompensation of LBL membranes. We also discuss the factors affecting overcompensation level with respect to two different time scales. Furthermore, we examine the relationship between overcompensation level and salinity stability of LBL membranes, considering physical (osmotic pressure) and chemical (Le Chatelier's principle) aspects. Our analysis demonstrates that the salinity stability of LBL NF membranes in highly saline solutions can be improved by selecting PEs with stronger binding strength, increasing the overcompensation level, and chemical crosslinking. These methods not only enhance the salinity stability of LBL NF membranes but also offer greater potential for their future application in highly saline streams
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