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Hydrogen sulfide positively regulates autophagy and the expression of hypoxia response-related genes under submergence to enhance the submergence tolerance of Arabidopsis. Flooding seriously endangers agricultural production, and it is quite necessary to explore the mechanism of plant response to submergence for improving crop yield. Both hydrogen sulfide (H

Drought represents a major threat to crop growth and yields. Strigolactones (SLs) contribute to regulating shoot branching by targeting the SUPPRESSOR OF MORE AXILLARY GROWTH2 (MAX2)-LIKE6 (SMXL6), SMXL7 and SMXL8 for degradation in a MAX2-dependent manner in Arabidopsis. Although SLs are implicated in plant drought response, the functions of the SMXL6, 7 and 8 in the SL-regulated plant response to drought stress have remained unclear. Here, we performed transcriptomic, physiological and biochemical analyses of smxl6, 7, 8 and max2 plants to understand the basis for SMXL6/7/8-regulated drought response. We found that three D53 (DWARF53)-Like SMXL members, SMXL6, 7 and 8, are involved in drought response as the smxl6smxl7smxl8 triple mutants showed markedly enhanced drought tolerance compared to wild type (WT). The smxl6smxl7smxl8 plants exhibited decreased leaf stomatal index, cuticular permeability and water loss, and increased anthocyanin biosynthesis during dehydration. Moreover, smxl6smxl7smxl8 were hypersensitive to ABA-induced stomatal closure and ABA responsiveness during and after germination. In addition, RNA-sequencing analysis of the leaves of the D53-like smxl mutants, SL-response max2 mutant and WT plants under normal and dehydration conditions revealed an SMXL6/7/8-mediated network controlling plant adaptation to drought stress via many stress- and/or ABA-responsive and SL-related genes. These data further provide evidence for crosstalk between ABA- and SL-dependent signaling pathways in regulating plant responses to drought. Our results demonstrate that SMXL6, 7 and 8 are vital components of SL signaling and are negatively involved in drought responses, suggesting that genetic manipulation of SMXL6/7/8-dependent SL signaling may provide novel ways to improve drought resistance.

Background Emergency and intensive care unit nurses are the main workforce fighting against COVID-19. Their professional identity may affect whether they can actively participate and be competent in care tasks during the pandemic. Objective To examine the level of and changes in professional identity of Chinese emergency and intensive care unit nurses as the COVID-19 pandemic builds. Methods A cross-sectional survey composed of the Professional Identity Scale for Nurses plus 2 open-ended questions was administered to Chinese emergency and intensive care unit nurses through an online questionnaire. Results Emergency and intensive care unit nurses had a medium level of professional identity. Participants’ total and item mean scores in 5 professional identity dimensions were higher than the professional identity norm established by Liu (P < .001). The greatest mean item score difference was in the dimension of professional identity evaluation (3.57 vs 2.88, P < .001). When asked about their feelings witnessing the COVID-19 situation and their feelings about participating in frontline work, 68.9% and 83.9%, respectively, reported positive changes in their professional identity. Conclusions The professional identity of emergency and intensive care unit nurses greatly improved during the early stages of the COVID-19 pandemic. This finding may be attributed to more public attention and recognition of nurses’ value, nurses’ professional fulfillment, and nurses’ feelings of being supported, motivated, respected, and valued.

To understand the functions of Populus euphratica CPD (PeCPD) and DWF4 (PeDWF4), the responses to exogenous phytohormone in Arabidopsis-PeCPD and -PeDWF4 transgenic lines (PeCPD-TL and PeDWF4-TL) and corresponding wild type (WT) seedlings were investigated. Results showed that all of PeCPD-TL, PeDWF4-TL and WT seedlings cultured on the mediums containing 2,4-dichlorophenoxyacetic acid (2,4-D) + 6-benzylaminopurin (6-BA) or 2,4-D + 6-BA + brassinolide (BL) could be dedifferentiated to callus with 100% frequency, but they displayed strong differences in callus formation sites, callus growth rates (CGRs) and tissue dedifferentiation degrees. On the medium containing 2,4-D alone, the seedlings of all the plants could formed callus, but callus formation times (CFTs) were delayed, and callus formation rates (CFRs) were differentially decreased. After adding lower concentrations of BL, their CFRs were all restored to 100%, but tissue dedifferentiation degrees were obviously lower than these on the mediums with 2,4-D + 6-BA or 2,4-D + 6-BA + BL. On the mediums containing 6-BA or 6-BA + BL, the seedlings of all the plants failed to produce callus. Semi-quantitative RT-PCR analysis also showed that the transcription levels of PeCPD, PeDWF4, AtCPD and AtDWF4 in PeCPD-TL, PeDWF4-TL and WT were evidently different. These results suggest that PeCPD and PeDWF4 play similar but not exactly the same roles in the regulation of callus morphogenesis of Arabidopsis seedlings, and that BL can partially replace the role of cytokinin to induce callus formation through interacting with auxin.

As the global climate changes, the frequency and severity of flood disasters have increased significantly, seriously affecting agricultural production. Hydrogen sulfide (H2S), as a gaseous signal molecule, plays an important role in plant development and stress adaptation. Previous studies suggested that H2S acts as an oxygen sensor when animals experience hypoxia. However, the role of H2S in the response and adaptation to flooding-induced hypoxia stress in plants is poorly understood. Here, we report that pretreatment with exogenous H2S or Cys significantly improved tolerance to submergence in Arabidopsis. Total submergence of soil-grown Arabidopsis increased the levels of endogenous H2S and its main endogenously generated product, cysteine (Cys) over time, and altered the expression of H2S or Cys biosynthesis- or metabolism-related genes, implying that the H2S-Cys homeostasis may contribute to regulation of tolerance to flooding. Transcriptomic and metabolomic analyses demonstrated that exogenous H2S-pretreatment activated hypoxia-responsive transcription factors and hypoxia sensing-related genes in a timely manner and limited cellular activities associated with growth through regulation of hormonal signaling, but had less influence on transcripts associated with photosynthesis. H2S-pretreatment also altered the levels of metabolites, particularly of amino acids and plant hormones, during submergence. Taken together, this study provides new insight into how H2S regulates tolerance to submergence-induced hypoxia stress and lays the foundation to design new strategies for the improvement of submergence resistance in crops.

Radio frequency identification (RFID) is one of the key technologies in Internet of Things. The mass and uncertainty of RFID raw data limit the development of the technology seriously. Through the analysis of the uncertain data, an RFID data cleaning framework based on selection mechanism (CFBS) is established. The framework introduces selection mechanism, and can select the optimal cleaning lines according to the cleaning nodes’ judgment conditions. It reduces the delay generated by data transmission and cleaning, because it needn’t travel all the cleaning nodes in cleaning framework. The experimental results show that the cleaning framework can ease the pressure of data transmission, and improve the efficiency of data cleaning greatly.