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Summary: Arabidopsis RESISTANCE TO POWDERY MILDEW 8.1 (RPW8.1) is an important tool for engineering broad‐spectrum disease resistance against multiple pathogens. Ectopic expression of RPW8.1 leads to enhanced disease resistance with cell death at leaves and compromised plant growth, implying a regulatory mechanism balancing RPW8.1‐mediated resistance and growth. Here, we show that RPW8.1 constitutively enhances the expression of transcription factor WRKY51 and activates salicylic acid and ethylene signalling pathways; WRKY51 in turn suppresses RPW8.1 expression, forming a feedback regulation loop. RPW8.1 and WRKY51 are both induced by pathogen infection and pathogen−/microbe‐associated molecular patterns. In ectopic expression of RPW8.1 background (R1Y4), overexpression of WRKY51 not only rescues the growth suppression and cell death caused by RPW8.1, but also suppresses RPW8.1‐mediated broad‐spectrum disease resistance and pattern‐triggered immunity. Mechanistically, WRKY51 directly binds to and represses RPW8.1 promoter, thus limiting the expression amplitude of RPW8.1. Moreover, WRKY6, WRKY28 and WRKY41 play a role redundant to WRKY51 in the suppression of RPW8.1 expression and are constitutively upregulated in R1Y4 plants with WRKY51 being knocked out (wrky51 R1Y4) plants. Notably, WRKY51 has no significant effects on disease resistance or plant growth in wild type without RPW8.1, indicating a specific role in RPW8.1‐mediated disease resistance. Altogether, our results reveal a regulatory circuit controlling the accumulation of RPW8.1 to an appropriate level to precisely balance growth and disease resistance during pathogen invasion. [ABSTRACT FROM AUTHOR]

Confidential and stable complex systems are characterized by high confidentiality requirements, continuous and stable operation requirements, and complex network structure, but existing evaluation models has a single dimension of security objectives and lack the correlation analysis among indicators. In view of this, a comprehensive security evaluation model based on the correlation analysis of indicators is proposed and eight security objectives covering confidentiality, availability, controllability, identifiability, personnel organization, risk management, enterprise grading and sustainability at three levels of product, system and service have been established. Taking the confidentiality of the smart medical IoT as an example, a sorting and weight confirmation algorithm based on index correlation is constructed, and the fuzzy comprehensive evaluation method is used to evaluate the selected system.

The continuous urbanization leads to increasing pressure on the ecological environment. It is a key point to measure regional ecological environment quality objectively, accurately and quickly from multiple directions in ecological research. In this study, the normalized vegetation index ( NDVI), wet index ( WET), land surface temperature ( LST), and normalized difference building-soil index (NDBSI) were extracted from the aspects of greenness, humidity, heat and dryness. The ecological quality of Xiongan New Area between 1995 and 2015 was evaluated by integrating selected indicators to measure the remote sensing ecological index ( RSEI) with principal component analysis technology based on ENVI platform. The results showed that the average RSEI of Xiongan New Area was 0.724, 0.710, and 0.682 in 1995, 2004 and 2015, respectively, showing a downward trend. RSEI mainly changed from 4, 5 to 1, 2 and 3 in the study area from 1995 to 2015. Ecological quality improved and deteriorated area accounted for 8.9% and 20.9% of the total area respectively. The ecological quality improved area was mainly located in the east and south of Xiongxian County, because a large area of forests and gardens was highly valued and strictly protected by the local government. The ecological quality deteriorated area was in the periphery of the town and the surrounding area of Baiyangdian due to the sharp decline of the water area of Baiyang-dian and the continuous urbanization. The three-year average correlation coefficient between RSEI and each component index was 0.80, which was higher than that between other component indices. Our results showed that RSEI could efficiently integrate the information of each component index and comprehensively and accurately reflect the ecological quality of the study area. [ABSTRACT FROM AUTHOR]

Summary: The Arabidopsis gene RESISTANCE TO POWDERY MILDEW8.1 (RPW8.1) confers resistance to virulent fungal and oomycete pathogens that cause powdery mildew and downy mildew, respectively. However, the underlying mechanism remains unclear. Here, we show that ectopic expression of RPW8.1 boosts pattern‐triggered immunity (PTI) resulting in enhanced resistance against different pathogens in both Arabidopsis and rice. In Arabidopsis, transcriptome analysis revealed that ectopic expression of RPW8.1‐YFP constitutively up‐regulates expression of many pathogen‐associated molecular pattern (PAMP‐)‐inducible genes. Consistently, upon PAMP application, the transgenic line expressing RPW8.1‐YFP exhibited more pronounced PTI responses such as callose deposition, production of reactive oxygen species, expression of defence‐related genes and hypersensitive response‐like cell death. Accordingly, the growth of a virulent bacterial pathogen was significantly inhibited in the transgenic lines expressing RPW8.1‐YFP. Conversely, impairment of the PTI signalling pathway from PAMP cognition to the immediate downstream relay of phosphorylation abolished or significantly compromised RPW8.1‐boosted PTI responses. In rice, heterologous expression of RPW8.1‐YFP also led to enhanced resistance to the blast fungus Pyricularia oryzae (syn. Magnaporthe oryzae) and the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo). Taken together, our data suggest a surprising mechanistic connection between RPW8.1 function and PTI, and demonstrate the potential of RPW8.1 as a transgene for engineering disease resistance across wide taxonomic lineages of plants. [ABSTRACT FROM AUTHOR]

A systematic study of the “size effect” of zirconia nanocrystals on nickel-catalyzed reforming of methane with CO2 shows that extremely stable Ni/ZrO2 catalysts are obtainable by hydrogen reduction of impregnated nickel nitrate on zirconia particles with sizes less than 25 nm. The same preparation method with larger particles of zirconia results in catalyst samples that deactivate rapidly in the reforming reaction. Comprehensive characterization with XRD, TPR/TPD, and TEM shows that the stable Ni/ZrO2 catalysts are better described as nanocomposites of size comparable to Ni metal (9-15 nm) and zirconia (7-25 nm) nanoparticles. The high percentage of the Ni-zirconia boundary or perimeter in the nanocomposite catalysts is believed to be crucial for the extremely stable catalytic activity. [ABSTRACT FROM AUTHOR]

Many rice microRNAs have been identified as fine-tuning factors in the regulation of agronomic traits and immunity. Among them, Osa-miR535 targets SQUAMOSA promoter binding protein-like 14 (OsSPL14) to positively regulate tillers but negatively regulate yield and immunity. Here, we uncovered that Osa-miR535 targets another SPL gene, OsSPL4, to suppress rice immunity against Magnaporthe oryzae. Overexpression of Osa-miR535 significantly decreased the accumulation of the fusion protein SPL4 TBS -YFP that contains the target site of Osa-miR535 in OsSPL4. Consistently, Osa-miR535 mediated the cleavage of OsSPL4 mRNA between the 10th and 11th base pair of the predicted binding site at the 3' untranslated region. Transgenic rice lines overexpressing OsSPL4 (OXSPL4) displayed enhanced blast disease resistance accompanied by enhanced immune responses, including increased expression of defense-relative genes and up-accumulated H 2 O 2 . By contrast, the knockout mutant osspl4 exhibited susceptibility. Moreover, OsSPL4 binds to the promoter of GH3.2, an indole-3-acetic acid-amido synthetase, and promotes its expression. Together, these data indicate that Os-miR535 targets OsSPL4 and OsSPL4-GH3.2, which may parallel the OsSPL14-WRKY45 module in rice blast disease resistance., (© 2022 The Authors. The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.)

The continuous urbanization leads to increasing pressure on the ecological environment. It is a key point to measure regional ecological environment quality objectively, accurately and quickly from multiple directions in ecological research. In this study, the normalized vegetation index (NDVI), wet index (WET), land surface temperature (LST), and normalized difference building-soil index (NDBSI) were extracted from the aspects of greenness, humidity, heat and dryness. The ecological quality of Xiongan New Area between 1995 and 2015 was evaluated by integrating selected indicators to measure the remote sensing ecological index (RSEI) with principal component analysis technology based on ENVI platform. The results showed that the average RSEI of Xiongan New Area was 0.724, 0.710, and 0.682 in 1995, 2004 and 2015, respectively, showing a downward trend. RSEI mainly changed from 4, 5 to 1, 2 and 3 in the study area from 1995 to 2015. Ecological quality improved and deteriorated area accounted for 8.9% and 20.9% of the total area respectively. The ecological quality improved area was mainly located in the east and south of Xiongxian County, because a large area of forests and gardens was highly valued and strictly protected by the local government. The ecological quality deteriorated area was in the periphery of the town and the surrounding area of Baiyangdian due to the sharp decline of the water area of Baiyangdian and the continuous urbanization. The three-year average correlation coefficient between RSEI and each component index was 0.804, which was higher than that between other component indices. Our results showed that RSEI could efficiently integrate the information of each component index and comprehensively and accurately reflect the ecological quality of the study area.

The Arabidopsis gene RESISTANCE TO POWDERY MILDEW8.1 (RPW8.1) confers resistance to virulent fungal and oomycete pathogens that cause powdery mildew and downy mildew, respectively. However, the underlying mechanism remains unclear. Here, we show that ectopic expression of RPW8.1 boosts pattern-triggered immunity (PTI) resulting in enhanced resistance against different pathogens in both Arabidopsis and rice. In Arabidopsis, transcriptome analysis revealed that ectopic expression of RPW8.1-YFP constitutively up-regulates expression of many pathogen-associated molecular pattern (PAMP-)-inducible genes. Consistently, upon PAMP application, the transgenic line expressing RPW8.1-YFP exhibited more pronounced PTI responses such as callose deposition, production of reactive oxygen species, expression of defence-related genes and hypersensitive response-like cell death. Accordingly, the growth of a virulent bacterial pathogen was significantly inhibited in the transgenic lines expressing RPW8.1-YFP. Conversely, impairment of the PTI signalling pathway from PAMP cognition to the immediate downstream relay of phosphorylation abolished or significantly compromised RPW8.1-boosted PTI responses. In rice, heterologous expression of RPW8.1-YFP also led to enhanced resistance to the blast fungus Pyricularia oryzae (syn. Magnaporthe oryzae) and the bacterial pathogen Xanthomonas oryzae pv. oryzae (Xoo). Taken together, our data suggest a surprising mechanistic connection between RPW8.1 function and PTI, and demonstrate the potential of RPW8.1 as a transgene for engineering disease resistance across wide taxonomic lineages of plants., (© 2017 The Authors. Plant Biotechnology Journal published by Society for Experimental Biology and The Association of Applied Biologists and John Wiley & Sons Ltd.)

Objective: To investigate the colony variation in Actinobacillus actinomycetemcomitans (Aa) from rough to smooth and recognize its different morphology during laboratory translations., Methods: Primary strains isolated from subgingival plaque of two juvenile periodontitis patients were repeatedly subcultured on agar plates and broth; for broth culture, every generation was translated in broth and on solid medium separately to observe the corresponding morphologies of Aa grow in broth., Results: Three smooth strains of Aa from the broth culture were obtained. The process was about 7-8 generations: colonies changed from a small and adherence phenotype to a bigger and sediment ones and finally the culture supernatant became turbid; the corresponding morphologies grow on agar exhibiting an adherent, small rough colony phenotype which had a star-shaped internal structure converted gradually to a kind of bigger, opaque, nonadherent, smooth phenotype, then the colony extended out from the margin of the colony and finally converted to a flat, almost parent morphology and the same time the star-like inner structure converted to a simpler and smaller type and finally disappeared. We could not get completely smooth variants of Aa from agar., Conclusions: The variation in colony morphology of Aa from rough to smooth is a process, in which the colony was gradually wetter and bigger and at the same time gradually lost the inner structure. During this process three colony morphologies at least can be seen, including rough, opaque smooth and almost translucent smooth.