Comparative genomics reveals the adaptation of ammonia-oxidising Thaumarchaeota to arid soils.

Thaumarchaeota are predominant in oligotrophic habitats such as deserts and arid soils, but their adaptations to these arid conditions are not well understood. In this study, we assembled 23 Thaumarchaeota genomes from arid and semi-arid soils collected from the Inner Mongolia Steppe and the Qinghai-Tibet Plateau. Using a comparative genomics approach, integrated with 614 Thaumarchaeota genomes from public databases, we identified the traits and evolutionary forces that contribute to their adaptations to aridity. Our results showed that the newly assembled genomes represent an early diverging group within the lineage of ammonia-oxidising Thaumarchaeota. While the genomic functions previously identified in arid soil lineages were conserved across terrestrial, shallow-ocean and deep-ocean lineages, several traits likely contribute to Thaumarchaeota's adaptation to aridity. These include chlorite dismutase, arsenate reductase, V-type ATPase and genes dealing with oxidative stresses. The acquisition and loss of traits at the last common ancestor of arid soil lineages may have facilitated the specialisation of Thaumarchaeota in arid soils. Additionally, the acquisition of unique adaptive traits, such as a urea transporter, Ca2+ :H+ antiporter, mannosyl-3-phosphoglycerate synthase and phosphatase, DNA end-binding protein Ku and phage shock protein A, further distinguishes arid soil Thaumarchaeota. This study provides evidence for the adaptations of Thaumarchaeota to arid soil, enhancing our understanding of the nitrogen and carbon cycling driven by Thaumarchaeota in drylands.

The Construction of Binary Phase Electrolyte Interface for Highly Stable Zinc Anodes.

Metal zinc is a promising anode candidate of aqueous zinc-ion batteries due to high theoretical capacity, low cost, and high safety. However, it often suffers from hydrogen evolution reaction (HER), dendrite growth, and formation of by-products. Herein, a triethyl phosphate (TEP)/H2 O binary phase electrolyte (BPE) interface is developed by introducing TEP-based electrolyte-wetted hydrophobic polypropylene (PP) separator onto the Zn anode surface. The equilibrium of the BPE interface depends on the comparable surface tensions of H2 O-based and TEP-based electrolytes on hydrophobic PP separator surfaces. The BPE interface induces Zn2+ solvation structure conversion from [Zn(H2 O)x ]2+ to [Zn(TEP)n (H2 O)y ]2+ , where most solvated H2 O molecules are removed. In [Zn(TEP)n (H2 O)y ]2+ , the residual H2 O molecules can be further constrained by the formation of H bonds between TEP and H2 O molecules. Consequently, the ionization of solvated H2 O molecules is effectively suppressed, and HER and by-products are effectively restricted on Zn anode surfaces in BPE. As a result, Zn anodes exhibit a high Coulombic efficiency of 99.12% and superior cycling performance of 6000 h, which is much higher than the case in single-phase aqueous electrolytes. To illustrate the feasibility of BPE in full cells, the Zn/Alx V2 O5 batteries are assembled based on the BPE and exhibited enhanced cycling performance.

Synergetic modulation on ionic association and solvation structure by electron-withdrawing effect for aqueous zinc-ion batteries.

Aqueous zinc-ion batteries are emerging as one of the most promising large-scale energy storage systems due to their low cost and high safety. However, Zn anodes often encounter the problems of Zn dendrite growth, hydrogen evolution reaction, and formation of by-products. Herein, we developed the low ionic association electrolytes (LIAEs) by introducing 2, 2, 2-trifluoroethanol (TFE) into 30 m ZnCl2 electrolyte. Owing to the electron-withdrawing effect of -CF3 groups in TFE molecules, in LIAEs, the Zn2+ solvation structures convert from larger aggregate clusters into smaller parts and TFE will construct H-bonds with H2O in Zn2+ solvation structure simultaneously. Consequently, ionic migration kinetics are significantly enhanced and the ionization of solvated H2O is effectively suppressed in LIAEs. As a result, Zn anodes in LIAE display a fast plating/stripping kinetics and high Coulombic efficiency of 99.74%. The corresponding full batteries exhibit an improved comprehensive performance such as high-rate capability and long cycling life.

Core root-associated prokaryotic community and its relationship to host traits across wheat varieties.

The root-associated microbiomes play important roles in plant growth. However, it is largely unknown how wheat variety evolutionary relatedness shapes each subcommunity in the root microbiome and, in turn, how these microbes affect wheat yield and quality. Here we studied the prokaryotic communities associated with the rhizosphere and root endosphere in 95 wheat varieties at regreening and heading stages. The results indicated that the less diverse but abundant core prokaryotic taxa occurred among all varieties. Among these core taxa, we identified 49 and 108 heritable amplicon sequence variants, whose variations in relative abundances across the root endosphere and rhizosphere samples were significantly affected by wheat variety. The significant correlations between phylogenetic distance of wheat varieties and prokaryotic community dissimilarity were only observed in non-core and abundant subcommunities in the endosphere samples. Again, wheat yield was only significantly associated with root endosphere microbiota at the heading stage. Additionally, wheat yield could be predicted using the total abundance of 94 prokaryotic taxa as an indicator. Our results demonstrated that the prokaryotic communities in the root endosphere had higher correlations with wheat yield and quality than those in the rhizosphere; thus, managing root endosphere microbiota, especially core taxa, through agronomic practices and crop breeding, is important for promoting wheat yield and quality.

Biocrust diazotrophs and bacteria rather than fungi are sensitive to chronic low N deposition.

Anthropogenic long-term nitrogen (N) deposition may dramatically impact biocrusts due to the overarching N limitation of soil biota in deserts. Even low levels of N may reach a critical loading threshold altering biocrust constituents and function. To identify the impact of chronic and continuous low levels of N deposition on biocrusts, we created a realistic gradient mirroring anthropogenic N addition rate (2:1 NH4 + : NO3 - rates: 0.3, 0.5, 1.0, 1.5, 3 g N m-2  yr-1 ) and measured the response of bacteria and fungi within cyanobacterial-dominated biocrusts over 8 years in a temperate desert, the Gurbantunggut Desert, China. We found that once N deposition reached 1.5 g N m-2  yr-1 biocrust bacterial communities, including diazotrophs, were altered while no such tipping point existed for fungi. Above the threshold, bacterial richness was enhanced, the relative abundance of Chloroflexi, FBP and Gemmatimonadetes was elevated, and diazotrophs shifted from being dominated by Nostocaceae and Scytonemataceae (Cyanobacteria) to free-living Bradyrhizobiaceae (Alphaproteobacteria). Alternatively, the relative recovery of a few fungal species within the Lecanorales, Pleosporales and Verrucariales became either enriched or diminished due to N deposition. The chronic addition of N resulted in a dense and interconnected bacterial co-occurrence network that accentuated a functional shift from networks dominated by phototrophic species within the Nostocaceae, Xenococcaceae, Phormidiaceae and Scytonemataceae (Cyanobacteria) to ammonia-oxidizing species within the Nitrosomonadaceae (Betaproteobacteria) and nitrifying bacteria [i.e. Nitrospiraceae (Nitrospirae)]. Based on structural equation models, the effects of N additions on biocrust constituents were imposed through indirect effects on pH, soil electrical conductivity and ammonium concentrations. In summary, biocrust constituents are generally insensitive to chronic low levels of N depositions until rates reach above 1.5 g N m-2  yr-1 with diazotrophs being the most sensitive biocrust constituents followed by bacteria and finally fungi. Ultimately once the threshold is reached N deposition favours biocrust constituents utilizing inorganic N and other C sources over relying on phototrophic and/or N-fixing cyanobacteria for C and N.

Integrated organic and inorganic fertilization and reduced irrigation altered prokaryotic microbial community and diversity in different compartments of wheat root zone contributing to improved nitrogen uptake and wheat yield.

The effect of long-term water and integrated fertilization on prokaryotic microorganisms and their regulation for crop nutrient uptake remains unknown. Therefore, the impact of soil water and integrated fertilization after eight years on prokaryotic microbial communities in different compartments of root zone and their association with wheat nitrogen (N) absorption and yield were investigated. The results showed that compared with fertilization treatments (F), water regimes (W) more drastically modulated the prokaryotic microbial community structure and diversity in bulk soil, rhizosphere and endosphere. The increase of irrigation improved the prokaryotic diversity in the rhizosphere and endosphere while decreased the diversity in the bulk soil. Application of organic fertilizers significantly improved soil organic matter (SOM) and nutrient contents, increased rhizosphere and endophytic prokaryotic microbial diversity, and elevated the relative abundance of aerobic ammonia oxidation and nitrification-related functional microorganisms in rhizosphere and endosphere. Increasing irrigation elevated the relative abundance of functional microorganisms related to aerobic ammonia oxidation and nitrification in the rhizosphere and endosphere. Soil water content (SWC) and NH4+-N as well as NO3--N were key predictors of prokaryotic microbial community composition under W and F treatments, respectively. Appropriate application of irrigation and organic fertilizers increased the relative abundance of some beneficial bacteria such as Flavobacterium. Water and fertilization treatments regulated the prokaryotic microbial communities of bulk soil, rhizosphere and endosphere by altering SWC and SOM, and provided evidence for the modulation of prokaryotic microorganisms to promote nitrogen uptake and wheat yield under long-term irrigation and fertilization. Conclusively, the addition of organic manure (50 %) with inorganic fertilizers (50 %) and reduced amount of irrigation (pre-sowing and jointing-period irrigation) decreased the application amount of chemical fertilizers and water, while increased SOM and nutrient content, improved prokaryotic diversity, and changed prokaryotic microbial community structure in the wheat root zone, resulting in enhanced nutrient uptake and wheat yield.

Rational Design of ZnMn2 O4 Quantum Dots in a Carbon Framework for Durable Aqueous Zinc-Ion Batteries.

Manganese oxides are promising cathode materials for aqueous zinc-ion batteries (ZIBs) due to their high energy density and low cost. However, in their discharging processes, the Jahn-Teller effect and Mn3+ disproportionation often lead to irreversible structural transformation and Mn2+ dissolution, deteriorating the cycling stability of ZIBs. Herein, ZnMn2 O4 quantum dots (ZMO QDs) were introduced into a porous carbon framework by in-situ electrochemically inducing Mn-MIL-100-derived Mn3 O4 quantum dots and the carbon composite. In such ZMO QDs and carbon composite, the quantum dot structure endows ZnMn2 O4 with a shorter ion diffusion route and more active sites for Zn2+ . The conductive carbon framework is beneficial to the fast transport of electrons. Furthermore, at the interface between the ZMO QDs and the carbon matrix, the Mn-O-C bonds are formed. They can effectively suppress the Jahn-Teller effect and manganese dissolution of discharge products. Therefore, Zn/ZMO QD@C batteries display remarkably enhanced electrochemical performance.

A Symmetric All-Organic Proton Battery in Mild Electrolyte.

All-organic proton batteries are attracting extensive attention due to their sustainability merits and excellent rate capability. Generally, strong acids (e.g. H2 SO4 ) have to be employed as the electrolytes to provide H+ for all-organic proton batteries due to the high H+ intercalation energy barrier. Until now, the design of all-organic proton batteries in mild electrolytes is still a challenge. Herein, a poly(2,9-dihydroquinoxalino[2,3-b]phenazine) (PO) molecule was designed and synthesized, where the adjacent C=N groups show two different chemical environments, resulting in two-step redox reactions. Moreover, the two reactions possess considerable voltage difference because of the large LUMO energy gap between PO and its reduction product. More impressively, the C=N groups endow the π-conjugated PO molecule with H+ uptake/removal in the ZnSO4 electrolyte. As a result, a symmetric all-organic proton battery is achieved in a mild electrolyte for the first time, which exhibits enhanced electrochemical performance and also broadens the chemistry of proton-based batteries.

Coordination of root auxin with the fungus Piriformospora indica and bacterium Bacillus cereus enhances rice rhizosheath formation under soil drying.

Moderate soil drying (MSD) is a promising agricultural technique that can reduce water consumption and enhance rhizosheath formation promoting drought resistance in plants. The endophytic fungus Piriformospora indica (P. indica) with high auxin production may be beneficial for rhizosheath formation. However, the integrated role of P. indica with native soil microbiome in rhizosheath formation is unclear. Here, we investigated the roles of P. indica and native bacteria on rice rhizosheath formation under MSD using high-throughput sequencing and rice mutants. Under MSD, rice rhizosheath formation was significantly increased by around 30% with P. indica inoculation. Auxins in rice roots and P. indica were responsible for the rhizosheath formation under MSD. Next, the abundance of the genus Bacillus, known as plant growth-promoting rhizobacteria, was enriched in the rice rhizosheath and root endosphere with P. indica inoculation under MSD. Moreover, the abundance of Bacillus cereus (B. cereus) with high auxin production was further increased by P. indica inoculation. After inoculation with both P. indica and B. cereus, rhizosheath formation in wild-type or auxin efflux carrier OsPIN2 complemented line rice was higher than that of the ospin2 mutant. Together, our results suggest that the interaction of the endophytic fungus P. indica with the native soil bacterium B. cereus favors rice rhizosheath formation by auxins modulation in rice and microbes under MSD. This finding reveals a cooperative contribution of P. indica and native microbiota in rice rhizosheath formation under moderate soil drying, which is important for improving water use in agriculture.

Patterns and Drivers of nirK-Type and nirS-Type Denitrifier Community Assembly along an Elevation Gradient.

nirK-type and nirS-type denitrifier communities mediate the conversion of nitrite to nitric oxide, which is the key step in denitrification. Results of previous studies have indicated that nirK-type and nirS-type denitrifiers may occupy different niches; however, the mechanisms and drivers of their responses to environmental changes within community assembly are poorly understood. In this study, we evaluated the distribution and assembly of nirK-type and nirS-type denitrifier communities along an elevation gradient from 1,800 to 4,100 m at Mount Gongga, China. Results showed that elevational patterns of alpha diversity in nirK-type and nirS-type denitrifier communities followed hump-backed patterns along the elevation gradient. However, nirK-type denitrifier communities formed two distinct clusters that were primarily separated by elevation, whereas nirS-type denitrifier communities formed three distinct clusters that were primarily separated by forest type along the elevation gradient. Moreover, deterministic processes were dominant in governing the assemblages of nirK-type and nirS-type denitrifiers. Soil pH was a key factor influencing the alpha and beta diversity of the nirK-type denitrifier communities, whereas plant richness was a primary variable influencing nirS-type denitrifiers. Additionally, our work revealed that soil denitrification potential was mainly explained by the variation in the beta diversity of denitrifier communities rather than the alpha diversity of denitrifier communities or denitrifier abundances over a large elevation gradient, and nirK-type denitrifiers played more important roles in soil denitrification. These results may contribute to predicting the consequences of global changes on denitrifier communities and their ecological services. IMPORTANCE Mount Gongga is the highest peak in the Hengduan Mountain region and is located at the southeastern fringe of the Tibetan Plateau, Sichuan Province, southwest China. As a transitional zone between the Tibetan Plateau and Sichuan Basin, Gongga Mountain features particularly diverse topography, geology, climate, and biodiversity and is a globally significant hot spot of biodiversity. In this contribution, we comprehensively describe the diversity and assembly of denitrifier communities along an elevation gradient on Gongga Mountain. Our findings established for the first time that the distribution patterns of beta diversity and driving factors differed between nirK-type and nirS-type denitrifier communities, and deterministic processes were dominant in shaping communities of denitrifiers. Moreover, the beta diversity of denitrifier communities rather than alpha diversity or denitrifier abundance played an important role in explaining denitrification potential, and the beta diversity of nirK-type denitrifier communities was more important than nirS-type denitrifier communities in soil denitrification. This work provides crucial insights into the spatial distribution of denitrifier communities and their ecological function and increases our understanding of the mechanisms underlying spatial distribution of community assembly along large elevation gradients.

The assembly of wheat-associated fungal community differs across growth stages.

Plant-associated fungal communities play a vital role in plant adaptations, physiological functions, and productivity. Therefore, it is important to reveal the mechanisms driving the assembly of these communities. Yet it is still not fully understood how community assembly and structure differentiate in plant compartments, growth seasons, and varieties at large geographic distances. In this study, we analyzed bulk soil and plant-associated fungal communities of five wheat varieties across two growth stages in three biogeographic sites with distances of about 324, 534, or 800 km apart between any two locations. Our results indicated that the fungal community varied primarily across the sample types (leaf endosphere, root endosphere, rhizosphere, and bulk soil), followed by growth stage. Compared with the regreening stage, lower α-diversity and more dominance by abundant species in the fungal community were observed in wheat-associated compartments (four sample types except for bulk soil) at the heading stage. Additionally, within each wheat-associated compartment across every growth stage, location had stronger effects on fungal community assembly than the wheat variety. The effects of variety on fungal community assembly were location specific as were the growth-stage patterns of varietal effects on leaf endosphere and rhizosphere fungal communities. We further detected a less diverse but abundant core fungal taxa that could be grouped into three clusters associated mainly with location. This study characterized the interplay effects between plant selection (compartment, growth stage, variety) and environment (location) on wheat-associated mycobiomes by determining drivers of fungal community assembly and core fungal taxa in field conditions. KEY POINTS: • Fungal community assembly was mainly shaped by sample type and growth stage • A lower diversity and more abundant core fungal taxa were shown at heading stage • Location had stronger effects on fungal community assembly than variety.

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Soil genesis is important for ecological restoration of red mud disposal area. Soil genesis of red mud and the microbial mechanism were studied by analyzing the change of physicochemical and biochemical characteristics of red mud. We analyzed the microbial community structure in a red mud disposal area without any human-induced restoration through a space for time substitution approach. The results showed that, with the increases of storage time, the physical parameters of porosity, water-stable aggregates content, and mean weight diameter increased, but the bulk density decreased. The chemical parameters, including pH, electrical conductivity, acid neutralizing capacity, and exchangeable sodium percentage, decreased with increasing storage time. The bio-chemical parameters of total organic carbon, total nitrogen, available phosphorus, microbial biomass carbon and basal respiration increased, but the metabolic quotient decreased. The Shannon diversity index increased, and the dominant microflora in red mud changed from the oxygenic photosynthetic bacteria Cyanobacteria and thanaerobic anoxygenic phototrophic bacteria Chlorobi and Chloroflexi to Proteobacteria, Actinobacteria and Firmicutes. The ratio between eutrophic and oligotrophic bacteria substantially increased. The micromorphology results showed that the microorga-nism-red mud aggregates were formed through adsorption, linkage, intertwinement and package between red mud particles, microbial cells and their metabolites. The red mud biotope changed spontaneously from extreme and oligotrophic into soil-like under natural stockpiling. The soil genesis process was mediated by microbes through increasing nutrient level, decreasing alkalinity and sali-nity, and improving soil structure.

Scalable Assembly of Flexible Ultrathin All-in-One Zinc-Ion Batteries with Highly Stretchable, Editable, and Customizable Functions.

Aqueous zinc-ion batteries (ZIBs) are considered to be a promising candidate for flexible energy storage devices due to their high safety and low cost. However, the scalable assembly of flexible ZIBs is still a challenge. Here, a scalable assembly strategy is developed to fabricate flexible ZIBs with an ultrathin all-in-one structure by combining blade coating with a rolling assembly process. Such a unique all-in-one integrated structure can effectively avoid the relative displacement or detachment between neighboring components to ensure continuous and effective ion- and/or loading-transfer capacity under external deformation, resulting in excellent structural and electrochemical stability. Furthermore, the ultrathin all-in-one ZIBs can be tailored and edited controllably into desired shapes and structures, further extending their editable, stretchable, and shape-customized functions. In addition, the ultrathin all-in-one ZIBs display the ability to integrate with perovskite solar cells to achieve an energy harvesting and storage integrated system. These enlighten a broad area of flexible ZIBs to be compatible with highly flexible and wearable electronics. The scaling-up assembly strategy provides a route to design other ultrathin all-in-one energy storage devices with stretchable, editable, and customizable behaviors.

microeco: an R package for data mining in microbial community ecology.

A large amount of sequencing data is produced in microbial community ecology studies using the high-throughput sequencing technique, especially amplicon-sequencing-based community data. After conducting the initial bioinformatic analysis of amplicon sequencing data, performing the subsequent statistics and data mining based on the operational taxonomic unit and taxonomic assignment tables is still complicated and time-consuming. To address this problem, we present an integrated R package-'microeco' as an analysis pipeline for treating microbial community and environmental data. This package was developed based on the R6 class system and combines a series of commonly used and advanced approaches in microbial community ecology research. The package includes classes for data preprocessing, taxa abundance plotting, venn diagram, alpha diversity analysis, beta diversity analysis, differential abundance test and indicator taxon analysis, environmental data analysis, null model analysis, network analysis and functional analysis. Each class is designed to provide a set of approaches that can be easily accessible to users. Compared with other R packages in the microbial ecology field, the microeco package is fast, flexible and modularized to use and provides powerful and convenient tools for researchers. The microeco package can be installed from CRAN (The Comprehensive R Archive Network) or github (https://github.com/ChiLiubio/microeco).

Phosphodiesterase-2 inhibitor reverses post-traumatic stress induced fear memory deficits and behavioral changes via cAMP/cGMP pathway.

Phosphodiesterase 2 is one of the phosphodiesterase (PDEs) family members that regulate cyclic nucleotide (namely cAMP and cGMP) concentrations. The present study determined whether PDE2 inhibition could rescue post-traumatic stress disorder (PTSD)-like symptoms. Mice were subjected to single prolonged stress (SPS) and treated with selective PDE2 inhibitor Bay 60-7550 (0.3, 1, or 3 mg/kg, i.p.). The behavioral tests such as forced swimming, sucrose preference test, open field, elevated plus maze, and contextual fear paradigm were conducted to determine the effects of Bay 60-7550 on SPS-induced depression- and anxiety-like behavior and fear memory deficits. The results suggested that Bay 60-7550 reversed SPS-induced depression- and anxiety-like behavior and fear memory deficits. Moreover, Bay 60-7550 prevented SPS-induced changes in the adrenal gland index, synaptic proteins synaptophysin and PSD95 expression, PKA, PKG, pCREB, and BDNF levels in the hippocampus and amygdala. These effects were completely prevented by PKG inhibitor KT5823. While PKA inhibitor H89 also prevented Bay 60-7550-induced pCREB and BDNF expression, but only partially prevented the effects on PSD95 expression in the hippocampus. These findings suggest that Bay 60-7550 protects mice against PTSD-like stress induced traumatic injury by activation of cGMP- or cAMP-related neuroprotective molecules, such as synaptic proteins, pCREB and BDNF.

Local community assembly mechanisms shape soil bacterial ß diversity patterns along a latitudinal gradient.

Biodiversity patterns across geographical gradients could result from regional species pool and local community assembly mechanisms. However, little has been done to separate the effects of local ecological mechanisms from variation in the regional species pools on bacterial diversity patterns. In this study, we compare assembly mechanisms of soil bacterial communities in 660 plots from 11 regions along a latitudinal gradient in eastern China with highly divergent species pools. Our results show that ß diversity does not co-vary with γ diversity, and local community assembly mechanisms appear to explain variation in ß diversity patterns after correcting for variation in regional species pools. The variation in environmental conditions along the latitudinal gradient accounts for the variation in ß diversity through mediating the strength of heterogeneous selection. In conclusion, our study clearly illustrates the importance of local community assembly processes in shaping geographical patterns of soil bacterial ß diversity.

Thermal-Gated Polymer Electrolytes for Smart Zinc-Ion Batteries.

Smart self-protection is essential for addressing safety issues of energy-storage devices. However, conventional strategies based on sol-gel transition electrolytes often suffer from unstable self-recovery performance. Herein, smart separators based on thermal-gated poly(N-isopropylacrylamide) (PNIPAM) hydrogel electrolytes were developed for rechargeable zinc-ion batteries (ZIBs). Such PNIPAM-based separators not only display a pore structure evolution from opened to closed states, but also exhibit a surface wettability transition from hydrophilic to hydrophobic behaviors when the temperature rises. This behavior can suppress the migration of electrolyte ions across the separators, realizing the self-protection of ZIBs at high temperatures. Furthermore, the thermal-gated behavior is highly reversible, even after multiple heating/cooling cycles, because of the reversibility of temperature-dependent structural evolution and hydrophilic/hydrophobic transition. This work will pave the way for designing thermal-responsive energy-storage devices with safe and controlled energy delivery.

Engineering Active Sites of Polyaniline for AlCl2 + Storage in an Aluminum-Ion Battery.

The reversible capacity of AlCl4 - intercalation/de-intercalation in conventional cathodes of aluminum-ion batteries (AIBs) is difficult to improve due to the large size of AlCl4 - anions. Therefore, it is highly desirable to realize the intercalation/de-intercalation of smaller Al-based ions. Here, we fabricated polyaniline/single-walled carbon nanotubes (PANI/SWCNTs) composite films and protonated the PANI nanorods. The protonation endows PANI with more active sites and enhanced conductivity. Hyper self-protonated PANI (PANI(H+ )) exhibits reversible AlCl2 + intercalation/de-intercalation during the discharge/charge process. As a result, the discharge capacity of the Al/PANI(H+ ) battery is twice as high as that of the initial composite films. PANI(H+ )@SWCNT electrodes also have a stable cycling life with only 0.003 % capacity decay per cycle over 8000 cycles. Owing to the excellent mechanical properties, PANI(H+ )@SWCNT composite films can act as the electrodes of flexible AIBs.

Distinct mechanisms shape soil bacterial and fungal co-occurrence networks in a mountain ecosystem.

Understanding microbial network assembly is a promising way to predict potential impacts of environmental changes on ecosystem functions. Yet, soil microbial network assembly in mountain ecosystems and its underlying mechanisms remain elusive. Here, we characterized soil microbial co-occurrence networks across 12 altitudinal sites in Mountain Gongga. Despite differences in habitats, soil bacterial networks separated into two different clusters by altitude, namely the lower and higher altitudes, while fungi did not show such a pattern. Bacterial networks encompassed more complex and closer relationships at the lower altitudes, while fungi had closer relationships at the higher altitudes, which could be attributed to niche differentiation caused by high variations in soil environments and plant communities. Both abiotic and biotic factors (e.g. soil pH and bacterial community composition) shaped bacterial networks. However, biotic factors played more important roles than the measured abiotic factors for fungal network assembly. Further analyses suggest that multiple mechanisms including niche overlap/differentiation, cross-feeding and competition between microorganisms could play important roles in shaping soil microbial networks. This study reveals microbial co-occurrence networks in response to different ecological factors, which provides important insights into our comprehensive understanding of microbial network assembly and their functional potentials in mountain ecosystems.

Flexible all-in-one zinc-ion batteries.

The recent development of flexible and wearable electronic devices has increased the demand for energy storage devices with excellent flexibility and structural stability. Aqueous zinc-ion batteries (ZIBs) are promising energy storage devices due to their low cost, high safety, and eco-friendliness. Therefore, flexible ZIBs have to be considered. Herein, we design the flexible all-in-one ZIBs, where the reduced graphene oxide/polyaniline (rGO/PANI) cathode, cellulose nanofiber (CNF) separator, and exfoliated graphene (EG)/Zn anode are integrated together using an all-freeze-casting strategy. The continuous seamless connection of such all-in-one ZIBs can avoid displacing and detaching between the electrodes and separator under different bending states and improve the load-transfer capacity and interface strength between the neighboring component layers. As a result, the all-in-one ZIBs show excellent flexibility and superior electrochemical stability under different bending states.