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Microplastics, as an emerging pollutant of global importance, have been well documented in aquatic ecosystems. However, little is known about the effects of microplastics on agroecosystems, particularly for soil microbial communities. Herein, microplastics collected from cotton fields in Xinjiang, China, were analysed with a scanning electron microscope (SEM) and high-throughput sequencing to investigate the attached bacterial communities. Microplastic surfaces, especially pits and flakes, were colonized by various microorganisms, suggesting active hydrolysis of plastic debris. The bacterial communities colonizing microplastics were significantly different in structure from those in the surrounding soil, plant litter and macroplastics. In addition, statistical analysis of differentially abundant OTUs showed that microplastics serve as a "special microbial accumulator" in farmland soil, enriching some taxa that degrade polyethylene, such as Actinobacteria, Bacteroidetes and Proteobacteria. Co-occurrence network analysis revealed that the biotic interactions between microorganisms on microplastics are as complex as those in soil, and Acidobacteria, Chloroflexi, Gemmatimonadetes, and Bacteroidetes are considered keystone species in bacterial communities. Collectively, the findings imply that microplastics acted as a distinct habitat for bacteria in farmland soil, which increases our understanding of microplastic pollution.

Long-lived T-memory stem cells (TSCM ) are key to both naturally occurring and vaccine-conferred protection against infection. These cells are characterized by the CD45RA+ CCR7+ CD95+ phenotype. Significant heterogeneity within the TSCM population is recognized, but distinguishing surface markers and functional characterization of potential subsets are lacking. Human CD8 TSCM subsets were identified in healthy subjects who had been previously exposed to CMV or Influenza (Flu) virus in flow cytometry by expression of CD122 or CXCR3, and then characterized in proliferation, multipotency, self-renewal, and intracellular cytokine production (TNF-α, IL-2, IFN-γ), together with transcriptomic profiles. The TSCM CD122hi -expressing subset (versus CD122lo ) demonstrated greater proliferation, greater multipotency, and enhanced polyfunctionality with higher frequencies of triple positive (TNF-α, IL-2, IFN-γ) cytokine-producing cells upon exposure to recall antigen. The TSCM CXCR3lo subpopulation also had increased proliferation and polyfunctional cytokine production. Transcriptomic analysis further showed that the TSCM CD122hi population had increased expression of activation and homing molecules, such as Ccr6, Cxcr6, Il12rb, and Il18rap, and downregulated cell proliferation inhibitors, S100A8 and S100A9. These data reveal that the TSCM CD122hi phenotype is associated with increased proliferation, enhanced multipotency and polyfunctionality with an activated memory-cell like transcriptional profile, and hence, may be favored for induction by immunization and for adoptive immunotherapy.

For double network (DN) hydrogels, their performance can be tuned by adjusting the interaction between their two networks. A novel DN hydrogel toughening approach is proposed by employing Janus nanoparticles (JNs) as crosslinkers to gain a conjoined-network hydrogel. First, a kind of JNs modified by amino groups and quaternary ammonium salt is synthesized, named R

Although the ubiquitous presence of microplastics in various environments is increasingly well studied, knowledge of the effects of microplastics on ambient microbial communities is still insufficient. To estimate the response of soil bacterial community succession and temporal turnover to microplastic amendment, a soil microcosm experiment was carried out with polyethylene microplastics. The soil samples under control and microplastic amendment conditions were collected for sequencing analysis using Illumina MiSeq technology. Microplastic amendment was found to significantly alter soil bacterial community structure, and the community differences were increased linearly with the incubation time. Compared with the turnover rate of bacterial community in the control samples (0.0103, p

This review focuses on the research progress of sulfide solid electrolytes. Two systems of (100-x)Li2S-xP2S5 and Li2S-MxSy-P2S5 are systematically reviewed from four aspects, the crystal structure, conductivity, stability and application. The methods for preparing sulfide solid electrolytes are summarized, and, their advantages and disadvantages are compared and analysed. Sulfide solid electrolytes with high conductivities are closely related to their crystal structures, and they can be improved via doping, such as substitution doping, interstitial doping, dual-doping, etc. The conductivities are introduced and summarized according to their classifications. Experimental studies and theoretical results are discussed in parallel to illustrate the relationship between the conductivity and crystal structure. Furthermore, the stabilities of sulfide electrolytes with lithium metal, active materials, organic solvents and humid air are reviewed separately, and corresponding methods for improvement are proposed. Finally, according to the different functions of sulfide electrolytes in all-solid-state lithium batteries (ASSLBs), they are categorized and generalized scientifically in terms of composite electrolyte, buffer material and electrolyte. Additionally, the techniques proposed in the recent works to achieve sufficient contact between the sulfide solid electrolyte and the electrode in the ASSLBs are summarized. The present review aims to provide a thorough understanding of the properties of sulfide solid electrolytes, including conductivity, structure, and stability, to allow for more efficient and target-oriented research to improve the performance of sulfides-based ASSLBs.

In this work, we developed a very facile strategy, i.e. dual dynamic crosslinking, to prepare a high performance injectable hydrogel. Poly(vinyl alcohol) (PVA) was crosslinked by 4-carboxyphenylboronic acid (CPBA) through the generation of borate bonding and ionic interaction to bridge the polymer chains in the presence of calcium ions. The dynamic gathering of CPBA could induce a self-reinforcing effect inside the hydrogel matrix, leading to high tensile and compressive moduli of the hydrogel over 1.0 MPa including the highest compressive modulus up to 5.6 MPa. Meanwhile, the mechanical properties of the hydrogel can be broadly and accurately tuned. And owing to the flexible PVA network, the hydrogel is ultra-tough, showing maximum tensile strain, tensile and compressive fracture energies up to 1600%, 600 kJ m−2 and 25 kJ m−2, respectively. Besides, the dynamic bonding overcomes the barriers to forming an injected strong hydrogel, e.g. to obtain a modulus and a fracture energy exceeding 1.0 MPa and 40 kJ m−2, by using a commercial dual-syringe kit under physiological conditions. Such a mild gelation procedure benefits the administration, 3D encapsulation and proliferation of cells of the hydrogels. The application of the PVA hydrogel was demonstrated by effective cartilage repair.

The inferior cycle performance of All-solid-state lithium batteries (ASSLBs) resulting from the low mixed ionic and electronic conductivity in the electrodes, as well as the large interfacial resistance between the electrodes and the electrolyte need to be overcome urgently for commercial applications. Here, an advanced cell construction strategy has been proposed, in which a cohesive and highly conductive poly(oxyethylene) (PEO)-based electrolyte is employed both in the cathode layer and in the interface of the electrolyte/anode, leading to an ASSLB with superior interfacial contact between the electrolyte and the electrodes, and forming a three-dimensional ionic conductive network in the cathode layer. Especially, the NASICON-type ionic conductor covered with the PEO-based polymer, integrating the advantages of an inorganic electrolyte and organic electrolyte, presents an enhanced electrochemical stability and an excellent compatibility with the Li electrode. Consequently, the ASSLBs of LiFePO4 (LFP)/Li with this advanced construction strategy exhibit excellent interfacial compatibility, ultralong cycle life and high capacity, i.e., a reversible discharge capacity maintained at 127.8 mA h g−1 for the 1000th cycle at 1C with a retention of 96.6%, and an initial discharge capacity of 153.4 mA h g−1 with a high retention of 99.9% after 200 cycles at 0.1C. Besides, the high-voltage monopolar stacked batteries with a bipolar structure can be fabricated conveniently, showing an open circuit voltage (OCV) of 6.63 V with a good cycle performance. In particular, the ASSLBs present outstanding safety in terms of nail penetration and burning in fire. Therefore, this advanced cell construction strategy may generate tremendous opportunities in the search for novel emerging solid-state lithium metal batteries.

For treating bone defects in periarticular fractures, there is a lack of biomaterial with injectable characteristics, tough structure, and osteogenic capacity for providing a whole-structure support and osteogenesis in the defect area. An injectable hydrogel is an ideal implant, however is weak as load-bearing scaffolds. Herein, a new strategy, i.e., an in situ formation of "active" composite double network (DN), is raised for the preparation of an injectable strong hydrogel particularly against compression. As a demonstration, 4-carboxyphenylboronic acid grafted poly(vinyl alcohol) (PVA) is crosslinked using calcium ions to provide a tough frame while bioactive glass (BG) microspheres are associated by poly(ethylene glycol) to obtain an interpenetrated inorganic network for reinforcement. The injected PVA/BG DN hydrogel gains compressive strength, modulus, and fracture energy of 34 MPa, 0.8 MPa, and 40 kJ m-2 , respectively. Then, the properties can be "autostrengthened" to 57 MPa, 2 MPa, and 65 kJ m-2 by mineralization in 14 days. In vivo experiments prove that the injected DN hydrogel is more efficient to treat femoral supracondylar bone defects than the implanted bulk DN gel. The work suggests a facile way to obtain a strong hydrogel with injectability, cytocompatibility, and tailorable functionality.

Three types of inorganic electrolytes [Li10GeP2S12 (LGPS), 75Li2S·24P2S5·1P2O5 (LPOS), Li1.5Al0.5Ge1.5(PO4)3 (LAGP)] with different particle sizes and electrochemical properties are selected as active fillers incorporated into poly(ethylene oxide) (PEO) matrix to fabricate hybrid solid electrolytes. The optimum composition of each filler is found in consideration of ionic conductivity. Their electrochemical characteristics are investigated. The optimal conductivities are 1.60 × 10−5, 1.18 × 10−5, and 2.12 × 10−5 S cm−1 at room temperature for PEO-1%LGPS, PEO-1%LPOS, and PEO-20%LAGP, respectively. The electrochemical stability windows of these hybrid solid electrolytes are all above 5 V (vs. Li+/Li). The results show that these fillers have positive effects on the ionic conductivity, lithium ion transference number, and electrochemical stability. The relationship between the type of filler and electrochemical properties has been investigated. All-solid-state cells LiFePO4/Li are fabricated and present fascinating electrochemical performance with high capacity retention and good cycling stability. This work provides promising electrolytes prepared by a simple method.

A new class of copolymer electrolytes with tunable network structure is successfully designed and prepared via a facile one-pot reaction. The trimethylolpropane triglycidyl ether (TMPEG) is cross-linked with poly (ethylene glycol) diamine (NPEG) to create well-defined solid network polymer electrolyte (SNPE). The network structure could be tuned by changing the molar ratio of TMPEG and NPEG or the molecular weight of NPEG. The effects of molecular weight of NPEG and molar ratio of EO/Li + on the ionic conductivity are systematically investigated. The optimal electrolyte TMPEG-NPEG4K[2:1]-16:1 presents a maximum conductivity of 1.10 × 10 −4 S cm −1 under 30 °C, and an 18-fold ionic conductivity enhancement in that of PEO-based electrolyte. Furthermore, it also exhibits wide electrochemical window (0–5.4 V), excellent compatibility with metallic Li, and superior mechanical properties. The all-solid-state lithium batteries LiFePO 4 /Li are assembled with TMPEG-NPEG4K[2:1]-16:1 electrolyte, and present good cycling and rate performance under 60 °C. The initial discharge specific capacities of the batteries are 161.7 mAh g −1 at 0.2 C and 132.7 mAh g −1 at 1 C, and the capacity retention ratio can be retained at 90.6% and 90.5% after 100 cycles. This new copolymer electrolyte may become a promising candidate for applications in all-solid-state lithium battery.

Four types of Li 1.5 Al 0.5 Ge 1.5 (PO 4 ) 3 (LAGP) with different particle sizes are selected as active fillers incorporated into polyethylene oxide (PEO) matrix to fabricate PEO/LAGP hybrid electrolytes at drying room. The results show that LAGP particles have a positive effect on the ionic conductivity, lithium ion transference number, electrochemical stabilities and mechanical properties. Among the PEO/LAGP hybrid electrolytes, the PEO-20%LAGP-I hybrid electrolyte exhibits a maximum ionic conductivity of 6.76 × 10 − 4 S cm − 1 and an electrochemical window of 0–5.3 V at 60 °C. The possible reasons for conductivities improving are discussed through characterizing the phase transition behaviors of electrolytes. All-solid-state battery LiFePO 4 /Li is fabricated and presents fascinating electrochemical performance with high capacity retention (close to 90% after 50 cycles at 60 °C) and attractive capacities of 166, 155, 143 and 108 mAh g − 1 at current rates of 0.1, 0.2, 0.5 and 1 C, respectively. This work provides a promising PEO/LAGP hybrid electrolyte prepared by a simple method which can be manufactured easily in industry scale.

A new solid polymer electrolyte (SPE) PEO-LiTFSI-1%LGPS-10%SN is successfully prepared via a convenient method with low cost. The effect of SN on the ionic conductivity of PEO-based electrolyte is systematically investigated. It presents a maximum conductivity of 9.10 × 10 −5 S·cm −1 at 25 °C, and a 15-fold ion conductivity enhancement in PEO-LiTFSI. It exhibits wide electrochemical window (0–5.5 V) and excellent compatibility with metallic Li. The LiFePO 4 /Li batteries exhibit a good cycling and rate performance under 40 °C, whose maximum discharge specific capacity at 0.1 C is 160.6 mAh·g −1 , and 94.7% can be retained after 60 cycles. At 0.5C, the maximum discharge specific capacity is 138.4 mAh·g −1 , and capacity retention close to 90% even after 100 cycles. The reasons of activation process are discussed. This new SPE with outstanding electrochemical performance is a promising solid electrolyte candidate for applications in all-solid-state lithium battery.

Li10GeP2S12 (LGPS) is incorporated into polyethylene oxide (PEO) matrix to fabricate composite solid polymer electrolyte (SPE) membranes. The lithium ion conductivities of as-prepared composite membranes are evaluated, and the optimal composite membrane exhibits a maximum ionic conductivity of 1.21 × 10−3 S cm−1 at 80 °C and an electrochemical window of 0–5.7 V. The phase transition behaviors for electrolytes are characterized by DSC, and the possible reasons for their enhanced ionic conductivities are discussed. The LGPS microparticles, acting as active fillers incorporation into the PEO matrix, have a positive effect on the ionic conductivity, lithium ion transference number and electrochemical stabilities. In addition, two kinds of all-solid-state lithium batteries (LiFeO4/SPE/Li and LiCoO2/SPE/Li) are fabricated to demonstrate the good compatibility between this new SPE membrane and different electrodes. And the LiFePO4/Li battery exhibits fascinating electrochemical performance with high capacity retention (92.5% after 50 cycles at 60 °C) and attractive capacities of 158, 148, 138 and 99 mAh g−1 at current rates of 0.1 C, 0.2 C, 0.5 C and 1 C at 60 °C, respectively. It is demonstrated that this new composite SPE should be a promising electrolyte applied in solid state batteries based on lithium metal electrode.

Soil archaea plays a vital role in the functioning of dryland ecosystems, which are expected to expand and get drier in the future as a result of climate change. However, compared with bacteria and fungi, the impacts of increasing aridity on archaea in these ecosystems remain largely unknown. Here, soil samples were collected along a typical aridity gradient in semi-arid regions in Inner Mongolia, China, to investigate whether and how the increasing aridity affects archaeal communities. The results showed that archaeal richness linearly decreased with increasing aridity. After partialling out the effects of soil properties based on partial least squares regression, the significant aridity-richness relationship vanished. The composition of archaeal communities was distributed according to the aridity gradient. These variations were largely driven by the changes in the relative abundance of Thaumarchaeota, Euryarchaeota and unclassified phyla. Niche-based processes were predominant in structuring the observed archaeal aridity-related pattern. The structural equation models further showed that aridity indirectly reduced archaeal richness through improving soil electrical conductivity (EC) and structured community composition by changing soil total nitrogen (TN). These results suggested that soil salinization and N-losses might be important mechanisms underlying the increasing aridity-induced alterations in archaeal communities, and highlighted the importance of soil niches in mediating the indirect impacts of increasing aridity on archaea.

Concerns regarding microplastic contamination have spread from aquatic environments to terrestrial systems with a growing number of studies have been reported. Notwithstanding, the potential effects on soil ecosystems remain largely unexplored. In this study, the effects of polyethylene microplastics on soil enzymatic activities and the bacterial community were evaluated, and the microbiota colonizing on microplastics were also investigated. Microplastic amendment (2000 fragments per kg soil) significantly increased the urease and catalase activities in soil after 15 days, and no discernible alteration of invertase activities was detected. Results from high-throughput sequencing of 16S rRNA revealed that the alpha diversities (richness, evenness, and diversity) of the microbiota in soil were not obviously changed by the PE amendment, whereas the diversity indexes of microbiota on plastic fragments were significantly lower than those in the control and amended soils. Different taxonomic composition was observed in between the control and amended soils after 90 days of incubation. Bacterial assemblages with distinct community structure colonized the PE microplastics. Additionally, several taxa including plastic-degrading bacteria and pathogens were more abundant on microplastics. Simultaneously, the predicted functional profiles showed that the pathways of amino acid metabolism and xenobiotics biodegradation and metabolism were higher on the microplastics. These results indicated that microplastics in soil, compared with those in aquatic environments, can also act as a distinct microbial habitat, potentially altering the ecological functions of soil ecosystems.

In this study, carbide slag loaded on ferric oxide (CS/Fe2O3) was synthesized as the catalyst for the transesterification of the soybean oil to biodiesel. The results indicated that CS/Fe2O3 catalyst showed superior catalytic activity and stability for the transesterification, which was related to the formation of Ca2Fe2O5 phase in the catalyst. In addition, the catalytic activity of CS/Fe2O3 was also affected by the precursors of the support and the molar ratio of calcium and iron in the catalyst. The catalyst with ferric chloride as the precursor performed the best catalytic performance, which was associated with the smallest mean pore diameter and the largest specific area. In addition, ferric oxide as a support could improve the stability of the CS/Fe2O3. Physical and chemical indexes of the produced biodiesel were analyzed and the results showed that the properties of the fuel met the requirement of the American Society for Testing Materials standard to be used as a green alternative source of the diesel.