Partially-hiding functional encryption for degree-2 polynomials with fine-grained access control

1 Introduction Boneh et al.[1]first systematically introduce the concept of Functional Encryption(FE)which overcomes all-or-nothing limitation of traditional public key encryption.However,FE hides a potential problem:even if the secret key is obtained legitimately,once it is released,it can be used forever.This leads to that the secret key may leak information inherently.To deal with this problem and make FE more practical,Abdalla et al.[2]recently constructed inner-product FE(IPFE)with fine-grained access control achieving strong security guarantees under standard assumptions.

Bacterial biogeography in China and its association to land use and soil organic carbon

●6102 high-quality sequencing results of soil bacterial samples were re-analyzed.●The type of land use was the principal driver of bacterial richness and diversity.●SOC content is positively correlated with key bacteria and total nitrogen content.Soil organic carbon(SOC)is the largest pool of carbon in terrestrial ecosystems and plays a crucial role in regulating atmospheric CO_(2) concentrations.Identifying the essential relationship between soil bacterial communities and SOC concentration is complicated because of many factors,one of which is geography.We systematically re-analyzed 6102 high-quality bacterial samples in China to delineate the bacterial biogeographic distribution of bacterial communities and identify key species associated with SOC concentration at the continental scale.The type of land use was the principal driver of bacterial richness and diversity,and we used machine learning to calculate its influence on microbial composition and their co-occurrence relationship with SOC concentration.Cultivated land was much more complex than forest,grassland,wetland and wasteland,with high SOC concentrations tending to enrich bacteria such as Rubrobacter,Terrimonas and Sphingomona.SOC concentration was positively correlated with the amounts of soil total nitrogen and key bacteria Xanthobacteraceae,Streptomyces and Acidobacteria but was negatively correlated with soil pH,total phosphorus and Micrococcaceae.Our study combined the SOC pool with bacteria and indicated that specific bacteria may be key factors affecting SOC concentration,forcing us to think about microbial communities associated with climate change in a new way.

Cadmium induced a non-coding RNA microRNA535 mediates Cd accumulation in rice

Identifying key regulators related to cadmium(Cd)tolerance and accumulation is the main factor for genetic engineering to improve plants for bioremediation and ensure crop food safety.MicroRNAs(miRNAs),as fine-tuning regulators of genes,participate in various abiotic stress processes.MiR535 is an ancient conserved non-coding small RNA in land plants,positively responding to Cd stress.We investigated the effects of knocking out(mir535)and overexpressing miR535(mir535 and OE535)under Cd stress in rice plants in this study.The mir535 plants showed better Cd tolerance than wild type(WT),whereas the OE535 showed the opposite effect.Cd accumulated approximately 71.9%and 127%in the roots of mir535 and OE535 plants,respectively,compared to WT,after exposure to 2μmol/L Cd.In brown rice,the total Cd accumulation of OE535 and mir535 was about 78%greater and 35%lower than WT.When growing in 2 mg/kg Cd of soil,the Cd concentration was significantly lower in mir535 and higher in OE535 than in the WT;afterward,we further revealed the most possible target gene SQUAMOSA promoter binding-like transcription factor 7(SPL7)and it negatively regulates Nramp5 expression,which in turn regulates Cd metabolism.Therefore,the CRISPR/Cas9 technology may be a valuable strategy for creating new rice varieties to ensure food safety.

Machine learning models reveal how biochar amendment affects soil microbial communities

The biochar amendment plays a vital role in maintaining soil health largely due to its effects on soil microbial communities.However,individual cases and the variability in biochar properties are not sufficient to draw universal conclusions.The present study aimed to reveal how the biochar application affects soil microbial communities.Metadata of 525 ITS and 128816S rRNA sequencing samples from previous studies were reanalyzed and machine learning models were applied to explore the dynamics of soil microbial communities under biochar amendment.The results showed that biochar considerably changed the soil bacterial and fungal community composition and enhanced the relative abundances of Acidobacteriota,Firmicutes,Basidiomycota,and Mortierellomycota.Biochar enhanced the robustness of the soil microbial community but decreased the interactions between fungi and bacteria.The random forest model combined with tenfold cross-validation were used to predict biomarkers of biochar response,indicating that potentially beneficial microbes,such as Gemmatimonadetes,Microtrichales,Candidatus_Kaiserbacteria,and Pyrinomonadales,were enriched in the soil with biochar amendment,which promoted plant growth and soil nutrient cycling.In addition,the biochar amendment enhanced the ability of bacteria to biosynthesize and led to an increase in fungal nutrient patterns,resulting in an increase in the abundance and diversity of saprophytic fungi that enhance soil nutrient cycling.The machine learning model more accurately revealed how biochar affected soil microbial community than previous independent studies.Our study provides a basis for guiding the reasonable use of biochar in agricultural soil and minimizing its negative effects on soil microecosystem.

The mechanism of different cyanobacterial responses to glyphosate

Glyphosate, the most extensively used herbicide globally, has raised ecotoxicological concerns because it can be transported into the aquatic environment and cause adverse effects on the aquatic system. However, the functional mechanism of glyphosate on cyanobacteria are not completely disentangled. In this study, we selected six common cyanobacteria to evaluate glyphosate effects on cyanobacterial growth in monoculture experiment. Results showed that the growth of five tested cyanobacterial species were promoted under different degrees, and only Pseudanabaena was inhibited by glyphosate. In the phylogenetic tree based on gene sequences of 5-enol-pyruvylshikimate-3-phosphate synthase(EPSPS),a target for glyphosate, we found that the position of Pseudanabaena is the closest to plant,which was sensitive to glyphosate, thereby explaining the inhibitory effect of Pseudanabaena following glyphosate exposure. The primary degraded metabolites or analogs did not induce cyanobacterial growth, laterally demonstrating that glyphosate was used as a source of phosphorus to accelerate cyanobacterial growth because phosphorus levels increased in the medium of glyphosate treatment. Overall, this study provides a better understanding of the influence of glyphosate on the composition of aquatic microbiota and explains the mechanism of cyanobacterial response to glyphosate.

Assessment of residual chlorine in soil microbial community using metagenomics

Chlorine-containing disinfectants have been widely used around the world for the prevention and control of the COVID-19 pandemic.However,at present,little is known about the impact of residual chlorine on the soil micro-ecological environment.Herein,we treated an experimental soil-plant-microbiome microcosm system by continuous irrigation with a low concentration of chlorine-containing water,and then analyzed the influence on the soil microbial community using metagenomics.After 14-d continuous chlorine treatment,there were no significant lasting effect on soil microbial community diversity and composition either in the rhizosphere or in bulk soil.Although metabolic functions of the rhizosphere microbial community were affected slightly by continuous chlorine treatment,it recovered to the original status.The abundance of several resistance genes changed by 7 d and recovered by 14 d.According to our results,the chlorine residue resulting from daily disinfection may present a slight long-term effect on plant growth(shoot length and fresh weight)and soil micro-ecology.In general,our study assisted with environmental risk assessments relating to the application of chlorine-containing disinfectants and minimization of risks to the environment during disease control,such as COVID-19.

Comparison of the toxicity of silver nanoparticles and silver ions on the growth of terrestrial plant model Arabidopsis thaliana

Silver nanoparticles （AgNPs） are one of the most widely used nanomaterials, but the mechanism of AgNP toxicity in terrestrial plants is still unclear. We compared the toxic effects of AgNPs and Ag＋ on Arabidopsis thaliana at the physiological, ultrastructural and molecular levels. AgNPs did not affect seed germination; however, they showed stronger inhibitory effect on root elongation than Ag＋ . The results of transmission electron microscopy and metal content analysis showed that AgNPs could be accumulated in leaves. These absorbed AgNPs disrupted the thylakoid membrane structure and decreased chlorophyll content, which can inhibit plant growth. By comparison, a small amount of Ag＋ was absorbed by seedlings, and it did not pronouncedly affect chloroplast structure and other metal ion absorption as AgNPs did. Compared with Ag＋ , AgNPs could alter the transcription of antioxidant and aquaporin genes, indicating that AgNPs changed the balance between the oxidant and antioxidant systems, and also affected the homeostasis of water and other small molecules within the plant body. All the data from physiological, ultrastructural and molecular levels suggest that AgNPs were more toxic than Ag＋ .

Alteration of dominant cyanobacteria in different bloom periods caused by abiotic factors and species interactions

Freshwater cyanobacterial blooms have drawn public attention because they threaten the safety of water resources and human health worldwide.Heavy cyanobacterial blooms outbreak in Lake Taihu in summer annually and vanish in other months.To find out the factors impacting the cyanobacterial blooms,the present study measured the physicochemical parameters of water and investigated the composition of microbial community using the 16S rRNA gene and internal transcribed spacer amplicon sequencing in the months with or without bloom.The most interesting finding is that two major cyanobacteria,Planktothrix and Microcystis,dramatically alternated during a cyanobacterial bloom in 2016,which is less mentioned in previous studies.When the temperature of the water began increasing in July,Planktothrix appeared first and showed as a superior competitor for M.aeruginosa in NO3^−-rich conditions.Microcystis became the dominant genus when the water temperature increased further in August.Laboratory experiments confirmed the influence of temperature and the total dissolved nitrogen(TDN)form on the growth of Planktothrix and Microcystis in a co-culture system.Besides,species interactions between cyanobacteria and non-cyanobacterial microorganisms,especially the prokaryotes,also played a key role in the alteration of Planktothrix and Microcystis.The present study exhibited the alteration of two dominant cyanobacteria in the different bloom periods caused by the temperature,TDN forms as well as the species interactions.These results helped the better understanding of cyanobacterial blooms and the factors which contribute to them.

Pollutant toxicology with respect to microalgae and cyanobacteria

Microalgae and cyanobacteria are fundamental components of aquatic ecosystems.Pollution in aquatic environment is a worldwide problem.Toxicological research on microalgae and cyanobacteria can help to establish a solid foundation for aquatic ecotoxicological assessments.Algae and cyanobacteria occupy a large proportion of the biomass in aquatic environments;thus,their toxicological responses have been investigated extensively.However,the depth of toxic mechanisms and breadth of toxicological investigations need to be improved.While existing pollutants are being discharged into the environment daily,new ones are also being produced continuously.As a result,the phenomenon of water pollution has become unprecedentedly complex.In this review,we summarize the latest findings on five kinds of aquatic pollutants,namely,metals,nanomaterials,pesticides,pharmaceutical and personal care products(PPCPs),and persistent organic pollutants(POPs).Further,we present information on emerging pollutants such as graphene,microplastics,and ionic liquids.Efforts in studying the toxicological effects of pollutants on microalgae and cyanobacteria must be increased in order to better predict the potential risks posed by these materials to aquatic ecosystems as well as human health.

Effects of imazethapyr spraying on plant growth and leaf surface microbial communities in Arabidopsis thaliana

Imazethapyr (IM) is an acetolactate synthase (ALS)-inhibiting herbicide that has been widely used in recent years.However,IM spraying can lead to the accumulation of herbicide residues in leaves.Here,we determined the effects of IM spraying on the plant growth and leaf surface microbial communities of Arabidopsis thaliana after 7 and 14 days of exposure.The results suggested that IM spraying inhibited plant growth.Fresh weight decreased to 48% and 26% of the control value after 7 and 14 days,respectively,of 0.035 kg/ha IM exposure.In addition,anthocyanin content increased 9.2-fold and 37.2-fold relative to the control content after 7 and 14 days of treatment,respectively.Furthermore,IM spraying destroyed the cell structures of the leaves,as evidenced by increases in the number of starch granules and the stomatal closure rate.Reductions in photosynthetic efficiency and antioxidant enzyme activity were observed after IM spraying,especially after 14 days of exposure.The diversity and evenness of the leaf microbiota were not affected by IM treatment,but the composition of community structure at the genus level was altered by IM spraying.Imazethapyr application increased the abundance of Pseudomonas,a genus that includes species pathogenic to plants and humans,indicating that IM potentially increased the abundance of pathogenic bacteria on leaves.Our findings increase our understanding of the relationships between herbicide application and the microbial community structures on plant leaves,and they provide a new perspective for studying the ecological safety of herbicide usage.

Diclofop-methyl affects microbial rhizosphere community and induces systemic acquired resistance in rice

Diclofop-methyl（DM）,a widely used herbicide in food crops,may partly contaminate the soil surface of natural ecosystems in agricultural area and exert toxic effects at low dose to nontarget plants.Even though rhizosphere microorganisms strongly interact with root cells,little is known regarding their potential modulating effect on herbicide toxicity in plants.Here we exposed rice seedlings（Xiushui 63） to 100 μg/L DM for 2 to 8 days and studied the effects of DM on rice rhizosphere microorganisms,rice systemic acquired resistance（SAR） and rice-microorganisms interactions.The results of metagenomic 16 S rDNA Illumina tags show that DM increases bacterial biomass and affects their community structure in the rice rhizosphere.After DM treatment,the relative abundance of the bacterium genera Massilia and Anderseniella increased the most relative to the control.In parallel,malate and oxalate exudation by rice roots increased,potentially acting as a carbon source for several rhizosphere bacteria.Transcriptomic analyses suggest that DM induced SAR in rice seedlings through the salicylic acid（but not the jasmonic acid） signal pathway.This response to DM stress conferred resistance to infection by a pathogenic bacterium,but was not influenced by the presence of bacteria in the rhizosphere since SAR transcripts did not change significantly in xenic and axenic plant roots exposed to DM.The present study provides new insights on the response of rice and its associated microorganisms to DM stress.

Leaf metabolic influence of glyphosate and nanotubes on the Arabidopsis thaliana phyllosphere

Chemical exposure can indirectly affect leaf microbiota communities,but the mechanism driving this phenomenon remains largely unknown.Results revealed that the co-exposure of glyphosate and multi-carbon nanotubes(CNTs)caused a synergistic inhibitory effect on the growth and metabolism of Arabidopsis thaliana shoots.However,only a slight inhibitory effect was induced by nanotubes or glyphosate alone at the tested concentrations.Several intermediate metabolites of nitrogen metabolism and fatty acid synthesis pathways were upregulated under the combined treatment,which increased the amount of energy required to alleviate the disruption caused by the combined treatment.Additionally,compared with the two individual treatments,the glyphosate/nanotube combination treatment induced greater fluctuations in the phyllosphere bacterial community members with low abundance(relative abundance(RA)<1%)at both the family and genus levels,and among these bacteria some plant growth promotion and nutrient supplement related bacteria were markable increased.Strikingly,strong correlations between phyllosphere bacterial diversity and metabolites suggested a potential role of leaf metabolism,particularly nitrogen and carbohydrate metabolism,in restricting the range of leaf microbial taxa.These correlations between phyllosphere bacterial diversity and leaf metabolism will improve our understanding of plant-microbe interactions and the extent of their drivers of variation and the underlying causes of variability in bacterial community composition.

Lessons learned from COVID-19 on potentially pathogenic soil microorganisms

1 Pathogenic soil microbes:an issue of international concern The current Coronavirus Disease 2019(COVID-19)pandemic,and previous H1N1 and SARS epidemics,were not completely accidental.The transfer of viruses and other microorganisms among humans,animals,plants,and environmental compartments(e.g.,soil or water)is a common natural phenomenon(Zhu et al.,2017;Zhu et al.,2020),but the frequencies of disease epidemics and pandemics have been increasing(Wu,2017;Zhang and Gao,2018).Agricultural intensification is postulated to be one of the most pervasive factors exacerbating these problems in the 20-first century(Foley et al.,2011).Current agricultural practices disturb the microbial world,accelerate the evolution of pathogen resistance and virulence,and together with host-range expansions and host jumps contribute to severe outbreaks of disease(Vannier et al.,2019).

Metabolomic modulations in a freshwater microbial community exposed to the fungicide azoxystrobin

An effective broad-spectrum fungicide,azoxystrobin(AZ),has been widely detected in aquatic ecosystems,potentially affecting the growth of aquatic microorganisms.In the present study,the eukaryotic alga Monoraphidium sp.and the cyanobacterium Pseudanabaena sp.were exposed to AZ for 7 days.Our results showed that 0.2–0.5 mg/L concentrations of AZ slightly inhibited the growth of Monoraphidium sp.but stimulated Pseudanabaena sp.growth.Meanwhile,AZ treatment effectively increased the secretion of total organic carbon(TOC)in the culture media of the two species,and this phenomenon was also found in a freshwater microcosm experiment(containing the natural microbial community).We attempted to assess the effect of AZ on the function of aquatic microbial communities through metabolomic analysis and further explore the potential risks of this compound.The metabonomic profiles of the microcosm indicated that the most varied metabolites after AZ treatment were related to the citrate cycle(TCA),fatty acid biosynthesis and purine metabolism.We thereby inferred that the microbial community increased extracellular secretions by adjusting metabolic pathways,which might be a stress response to reduce AZ toxicity.Our results provide an important theoretical basis for further study of fungicide stress responses in aquatic microcosm microbial communities,as well as a good start for further explorations of AZ detoxification mechanisms,which will be valuable for the evaluation of AZ environmental risk.

Enantioselective effects of imazethapyr residues on Arabidopsis thaliana metabolic profile and phyllosphere microbial communities

Imazethapyr(IM)is a widely used acetolactate synthase-inhibiting chiral herbicide.It has long-term residuals that may be absorbed by the human body through the edible parts of plants,such as vegetable leaves or fruits.Here,we selected a model plant,Arabidopsis thaliana,to determine the effects of R-IM and S-IM on its leaf structure,photosynthetic efficiency,and metabolites,as well as the structures of microorganisms in the phyllosphere,after 7 days of exposure.Our results indicated enantiomeric differences in plant growth between R-IM and S-IM;133μg/kg R-IM showed heavier inhibition of photosynthetic efficiency and greater changes to subcellular structure than S-IM.R-IM and S-IM also had different effects on metabolism and leaf microorganisms.S-IM mainly increased lipid compounds and decreased amino acids,while R-IM increased sugar accumulation.The relative abundance of Moraxellaceae human pathogenic bacteria was increased by R-IM treatment,indicating that R-IM treatment may increase leaf surface pathogenic bacteria.Our research provides a new perspective for evaluating the harmfulness of pesticide residues in soil,phyllosphere microbiome changes via the regulation of plant metabolism,and induced pathogenic bacterial accumulation risks.

Abundance cannot represent antibiotic resistance risk

Antibiotic resistance is increasing in the soil environments(Chen et al.,2019a;Zhu et al.,2019)and transferring into human body via plant microbiome,which can be exacerbated by the food chain,direct contact pathway,and globalization process(Chen et al.,2019b).