Dual-functional ionic liquids additive enables dendrite-free Zn anode with ultra-long cycle life over one year.

Zn anodes suffer from the formation of uncontrolled dendrites aggravated by the uneven electric field and the insulating by-product accumulation in aqueous zinc-ion batteries (AZIBs). Here, an effective strategy implemented by 1-butyl-3-methylimidazolium hydrogen sulfate (BMIHSO4) additive is proposed to synergistically tune the crystallographic orientation of zinc deposition and suppress the formation of zinc hydroxide sulfate for enhancing the reversibility on Zn anode surface. As a competing cation, BMI+ is proved to preferably adsorb on Zn-electrode compared with H2O molecules, which shields the "tip effect" and inhibits the Zn-deposition agglomerations to inducing the horizontal growth along Zn (002) crystallographic texture. Simultaneously, the protonated BMIHSO4 additives could remove the detrimental OH- in real-time to fundamentally eliminate the accumulation of 6Zn(OH)2·ZnSO4·4H2O and Zn4SO4(OH)6·H2O on Zn anode surface. Consequently, Zn anode exhibits an ultra-long cycling stability of one year (8762 h) at 0.2 mA cm-2/0.2 mAh cm-2, 3600 h at 2 mA cm-2/2 mAh cm-2 with a high plating cumulative capacity of 3.6 Ah cm-2, and a high average Coulombic efficiency of 99.6 % throughout 1000 cycles. This work of regulating Zn deposition texture combined with eliminating notorious by-products could offer a desirable way for stabilizing the Zn-anode/electrolyte interface in AZIBs.

Surface Degradation of Single-crystalline Ni-rich Cathode and Regulation Mechanism by Atomic Layer Deposition in Solid-State Lithium Batteries.

Single-crystalline Ni-rich cathode (SC-NCM) has attracted increasing interest owing to its greater capacity retention in advanced solid-state lithium batteries (SSLBs), while suffers from severe interfacial instability during cycling. Here, via atomic layer deposition, Li3 PO4 is introduced to coat SC-NCM (L-NCM), to suppress undesired side reaction and enhance interfacial stability. The dynamic degradation and surface regulation of SC-NCM are investigated inside a working SSLB by in situ atomic force microscopy (AFM). We directly observe the uneven cathode electrolyte interphase (CEI) and surface defects on pristine SC-NCM particle. Remarkably, the formed amorphous LiF-rich CEI on L-NCM maintains its initial structure upon cycling, and thus endows the battery with improved cycling stability and excellent rate capability. Such on-site tracking provides deep insights into surface mechanism and structure-reactivity correlation of SC-NCM, and thus benefits the optimizations of SSLBs.

In Situ Characterization of Over-Lithiation of Organosulfide-Based Lithium Metal Anodes.

Over-lithiated organosulfides, such as sulfurized polyacrylonitrile (SPAN), are promising candidates of lithium metal anode (LMA) protection since they could form robust solid electrolyte interphases (SEIs), which is the key toward stable lithium metal batteries. So far, the mechanism of over-lithiation and evolution of the electrode surface is poorly understood. Herein, several in situ techniques were employed to study the over-lithiation process in SPAN, including in situ Raman spectroscopy to reveal the chemical transformation and in situ electrochemical atomic force microscopy (EC-AFM) to visualize interfacial evolution. The results undoubtedly prove the breaking of the C-S bond and formation of the C-Li bond during the over-lithiation process. The nucleophilic C-Li could further trigger the decomposition of the electrolyte to form an inorganic-organic hybrid SEI on the surface of SPAN, which allows uniform Li deposition and significantly improves the cycle stability of LMAs, as supported by the in situ EC-AFM characterization as well as a series of full cell tests. New insights into the over-lithiation mechanism of SPAN should facilitate the design of organosulfides to construct stable lithium metal anodes.

Identification of an Apis cerana zinc finger protein 41 gene and its involvement in the oxidative stress response.

Zinc finger proteins (ZFPs) are a class of transcription factors that contain zinc finger domains and play important roles in growth, aging, and responses to abiotic and biotic stresses. These proteins activate or inhibit gene transcription by binding to single-stranded DNA or RNA and through RNA/DNA bidirectional binding and protein-protein interactions. However, few studies have focused on the oxidation resistance functions of ZFPs in insects, particularly Apis cerana. In the current study, we identified a ZFP41 gene from A. cerana, AcZFP41, and verified its function in oxidative stress responses. Real-time quantitative polymerase chain reaction showed that the transcription level of AcZFP41 was upregulated to different degrees during exposure to oxidative stress, including that induced by extreme temperature, UV radiation, or pesticides. In addition, the silencing of AcZFP41 led to changes in the expression patterns of some known antioxidant genes. Moreover, the activities of the antioxidant enzymes catalase (CAT), superoxide dismutase (SOD), peroxidase (POD), and glutathione S-transferase (GST) in AcZFP41-silenced honeybees were higher than those in a control group. In summary, the data indicate that AcZFP41 is involved in the oxidative stress response. The results provide a theoretical basis for further studies of zinc finger proteins and improve our understanding of the antioxidant mechanisms of honeybees.

Micromechanism in All-Solid-State Alloy-Metal Batteries: Regulating Homogeneous Lithium Precipitation and Flexible Solid Electrolyte Interphase Evolution.

Sulfide-based solid-state electrolytes (SSEs) matched with alloy anodes are considered as promising candidates for application in all-solid-state batteries (ASSBs) to overcome the bottlenecks of the lithium (Li) anode. However, an understanding of the dynamic electrochemical processes on alloy anode in SSE is still elusive. Herein, in situ atomic force microscopy gives insights into the block-formation and stack-accumulation behaviors of Li precipitation on an Li electrode, uncovering the morphological evolution of nanoscale Li deposition/dissolution in ASSBs. Furthermore, two-dimensional Li-indium (In) alloy lamellae and the homogeneous solid electrolyte interphase (SEI) shell on the In electrode reveal the precipitation mechanism microscopically regulated by the alloy anode. The flexible and wrinkle-structure SEI shell further enables the electrode protection and inner Li accommodation upon cycles, elucidating the functional influences of SEI shell on the cycling behaviors. Such on-site tracking of the morphological evolution and dynamic mechanism provide an in-depth understanding and thus benefit the optimizations of alloy-based ASSBs.

Dynamic Evolution of a Cathode Interphase Layer at the Surface of LiNi0.5Co0.2Mn0.3O2 in Quasi-Solid-State Lithium Batteries.

Intensive understanding of the surface mechanism of cathode materials, such as structural evolution and chemical and mechanical stability upon charging/discharging, is crucial to design advanced solid-state lithium batteries (SSLBs) of tomorrow. Here, via in situ atomic force microscopy monitoring, we explore the dynamic evolution process at the surface of LiNi0.5Co0.2Mn0.3O2 cathode particles inside a working SSLB. The dynamic formation process of the cathode interphase layer, with an inorganic-organic hybrid structure, was real-time imaged, as well as the evolution of its mechanical property by in situ scanning of the Derjaguin-Muller-Toporov modulus. Moreover, different components of the cathode interphase layer, such as LiF, Li2CO3, and specific organic species, were identified in detailat different stages of cycling, which can be directly correlated with the impedance buildup of the battery. In addition, the transition metal migration and the formation of new phases can further exacerbate the degradation of the SSLB. A relatively stable cathode interphase is key to improving the performance of SSLBs. Our findings provide deep insights into the dynamic evolution of surface morphology, chemical components and mechanical properties of the cathode interphase layer, which are pivotal for the performance optimization of SSLBs.

Reconfiguring Organosulfur Cathode by Over-Lithiation to Enable Ultrathick Lithium Metal Anode toward Practical Lithium-Sulfur Batteries.

An ultrathick lithium metal anode (LMA) is a prerequisite for developing practical lithium-sulfur (Li-S) batteries that simultaneously meet the requirements of high areal capacity, lean electrolyte, and limited excess Li. Inspired by the electrochemical process for an organosulfur cathode, herein, we reconfigure such a sulfur cathode by using an overlithiation strategy to enable the formation of a high performance LMA. Specifically, an applicable ultrathick LMA is successfully constructed by overlithiating a well-known organosulfur cathode material, sulfurized polyacrylonitrile (SPAN). SPAN contains a polymeric pyridine structure with an outstanding lithium-ion affinity, so that it can act as a lithiophilic matrix. More importantly, a Li2S-rich solid electrolyte interphase (SEI) can be generated on the surface of SPAN during the overlithiation process. The synergistic effect of the lithiophilic matrix and a robust SEI leads to a dense deposition of lithium, which enables one to form an ultrathick LMA (159 µm, 30 mAh cm-2) with high Coulombic efficiency (99.7%). Such an LMA paired with a sulfur cathode of high areal capacity (up to 16 mAh cm-2) shows stable cycling under practical conditions of a lean electrolyte (2.2 µL mgS-1) and a negative-to-positive capacity (N/P) ratio as low as 1.3. The applicability of the ultrathick LMA was further verified with Li-S pouch cells, indicating a highly prospective route toward realization of practical Li-S batteries.

Gender differences among homicide offenders with schizophrenia in Hunan Province, China.

This study aimed to understand the demographic, clinical and criminological characteristics of Chinese homicide offenders with schizophrenia from a gender-based perspective. Information on all homicide offenders with schizophrenia who received forensic psychiatric assessment between 2010 and 2016 in Hunan Province, China, was systematically retrieved (n = 669). Gender differences in the above characteristics were analyzed, and independent correlates of homicide were explored. The male to female ratio of homicide offenders was about 4:1. Proportionally more males were single, unemployed and younger when committing their first crime than was apparent in females. Male perpetrators were more often influenced by delusions. Females were more likely to target their close family members. For males, living in rural areas and having a family history of mental disorder were positively associated with homicide, while having a criminal history and being unemployed were negatively associated. For females, younger age was positively, while being unmarried and unemployment were negatively associated with homicide. Our results indicate significant gender differences among Chinese homicide offenders with schizophrenia in demographic, clinical and criminological characteristics and in independent correlates of homicide. Further research in this field, especially aims at determining risk factors for crime in this population, should take the gender differences into account.

Juvenile hormone mediates the positive effects of nitrogen fertilization on weight and reproduction in pea aphid.

BACKGROUND: The positive effects of nitrogen fertilization on the performance of phytophagous insects have been reported extensively; the physiological and molecular basis involved, however, is largely unclear. Here, we test experimentally whether enhancement of juvenile hormone (JH) is responsible for the increased weight and fecundity of pea aphid (Acyrthosiphon pisum) under nitrogen fertilization. RESULTS: Aphids fed on Medicago truncatula with nitrogen fertilization have a greater amino acid content, higher weight at the fourth instar and adult stage, and produce more offspring than those without nitrogen fertilization. Furthermore, nitrogen fertilization upregulates the transcripts of JH biosynthesis-related genes and increases JH titre at the fourth instar and adult stage, suggesting that JH is involved in the positive responses of aphids to nitrogen fertilization. Application of 100 ng JH increases adult weight and fecundity in aphids fed on M. truncatula without nitrogen fertilization. Conversely, impairing JH signalling by pharmacologically inhibiting the target of rapamycin pathway or by knocking down JH biosynthetic gene decreases adult weight and fecundity in aphids fed on M. truncatula with nitrogen fertilization, whereas application of JH rescued the phenotype. CONCLUSION: The increased JH titre at the fourth instar and adult stage is required for the increases of weight and fecundity of A. pisum under nitrogen fertilization. © 2018 Society of Chemical Industry.

The nitrate-reduction gene cluster components exert lineage-dependent contributions to optimization of Sinorhizobium symbiosis with soybeans.

Receiving nodulation and nitrogen fixation genes does not guarantee rhizobia an effective symbiosis with legumes. Here, variations in gene content were determined for three Sinorhizobium species showing contrasting symbiotic efficiency on soybeans. A nitrate-reduction gene cluster absent in S. sojae was found to be essential for symbiotic adaptations of S. fredii and S. sp. III. In S. fredii, the deletion mutation of the nap (nitrate reductase), instead of nir (nitrite reductase) and nor (nitric oxide reductase), led to defects in nitrogen-fixation (Fix- ). By contrast, none of these core nitrate-reduction genes were required for the symbiosis of S. sp. III. However, within the same gene cluster, the deletion of hemN1 (encoding oxygen-independent coproporphyrinogen III oxidase) in both S. fredii and S. sp. III led to the formation of nitrogen-fixing (Fix+ ) but ineffective (Eff- ) nodules. These Fix+ /Eff- nodules were characterized by significantly lower enzyme activity of glutamine synthetase indicating rhizobial modulation of nitrogen-assimilation by plants. A distant homologue of HemN1 from S. sojae can complement this defect in S. fredii and S. sp. III, but exhibited a more pleotropic role in symbiosis establishment. These findings highlighted the lineage-dependent optimization of symbiotic functions in different rhizobial species associated with the same host.

MucR Is Required for Transcriptional Activation of Conserved Ion Transporters to Support Nitrogen Fixation of Sinorhizobium fredii in Soybean Nodules.

To achieve effective symbiosis with legume, rhizobia should fine-tune their background regulation network in addition to activating key genes involved in nodulation (nod) and nitrogen fixation (nif). Here, we report that an ancestral zinc finger regulator, MucR1, other than its paralog, MucR2, carrying a frameshift mutation, is essential for supporting nitrogen fixation of Sinorhizobium fredii CCBAU45436 within soybean nodules. In contrast to the chromosomal mucR1, mucR2 is located on symbiosis plasmid, indicating its horizontal transfer potential. A MucR2 homolog lacking the frameshift mutation, such as the one from S. fredii NGR234, can complement phenotypic defects of the mucR1 mutant of CCBAU45436. RNA-seq analysis revealed that the MucR1 regulon of CCBAU45436 within nodules exhibits significant difference compared with that of free-living cells. MucR1 is required for active expression of transporters for phosphate, zinc, and elements essential for nitrogenase activity (iron, molybdenum, and sulfur) in nodules but is dispensable for transcription of key genes (nif/fix) involved in nitrogen fixation. Further reverse genetics suggests that S. fredii uses high-affinity transporters to meet the demand for zinc and phosphate within nodules. These findings, together with the horizontal transfer potential of the mucR homolog, imply an intriguing evolutionary role of this ancestral regulator in supporting nitrogen fixation.

Genetic divergence of bradyrhizobium strains nodulating soybeans as revealed by multilocus sequence analysis of genes inside and outside the symbiosis island.

The genus Bradyrhizobium has been considered to be a taxonomically difficult group. In this study, phylogenetics and evolutionary genetics analyses were used to investigate divergence levels among Bradyrhizobium strains nodulating soybeans in China. Eleven genospecies were identified by sequence analysis of three phylogenetic and taxonomic markers (SMc00019, thrA, and truA). This was also supported by analyses of eight genes outside the symbiosis island ("off-island" genes; SMc00019, thrA, truA, fabB, glyA, phyR, exoN, and hsfA). However, seven genes inside the symbiosis island ("island" genes; nifA, nifH, nodC, nodV, fixA, trpD, and rhcC2) showed contrasting lower levels of nucleotide diversity and recombination rates than did off-island genes. Island genes had significantly incongruent gene phylogenies compared to the species tree. Four phylogenetic clusters were observed in island genes, and the epidemic cluster IV (harbored by Bradyrhizobium japonicum, Bradyrhizobium diazoefficiens, Bradyrhizobium huanghuaihaiense, Bradyrhizobium liaoningense, Bradyrhizobium daqingense, Bradyrhizobium sp. I, Bradyrhizobium sp. III, and Bradyrhizobium sp. IV) was not found in Bradyrhizobium yuanmingense, Bradyrhizobium sp. II, or Bradyrhizobium elkanii. The gene flow level of island genes among genospecies is discussed in the context of the divergence level of off-island genes.

Replicon-dependent differentiation of symbiosis-related genes in Sinorhizobium strains nodulating Glycine max.

In order to investigate the genetic differentiation of Sinorhizobium strains nodulating Glycine max and related microevolutionary mechanisms, three housekeeping genes (SMc00019, truA, and thrA) and 16 symbiosis-related genes on the chromosome (7 genes), pSymA (6 genes), and pSymB (3 genes) were analyzed. Five distinct species were identified among the test strains by calculating the average nucleotide identity (ANI) of SMc00019-truA-thrA: Sinorhizobium fredii, Sinorhizobium sojae, Sinorhizobium sp. I, Sinorhizobium sp. II, and Sinorhizobium sp. III. These species assignments were also supported by population genetics and phylogenetic analyses of housekeeping genes and symbiosis-related genes on the chromosome and pSymB. Different levels of genetic differentiation were observed among these species or different replicons. S. sojae was the most divergent from the other test species and was characterized by its low intraspecies diversity and limited geographic distribution. Intergenic recombination dominated the evolution of 19 genes from different replicons. Intraspecies recombination happened frequently in housekeeping genes and symbiosis-related genes on the chromosome and pSymB, whereas pSymA genes showed a clear pattern of lateral-transfer events between different species. Moreover, pSymA genes were characterized by a lower level of polymorphism and recombination than those on the chromosome and pSymB. Taken together, genes from different replicons of rhizobia might be involved in the establishment of symbiosis with legumes, but these symbiosis-related genes might have evolved differently according to their corresponding replicons.