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Summary statement: High solar radiation exacerbated the negative effects of extreme drought on plant growth and fine root traits. Ectomycorrhizae did not compensate for fine roots under drought stress. Fine roots biomass determined the role of ectomycorrhizal fungi, supporting the energy limitation hypothesis. [ABSTRACT FROM AUTHOR]

Organosulfur materials containing sulfur–sulfur bonds are an emerging class of high‐capacity cathodes for lithium storage. However, it remains a great challenge to achieve rapid conversion reaction kinetics at practical testing conditions of high cathode mass loading and low electrolyte utilization. In this study, a Li‐rich pyrolyzed polyacrylonitrile/selenium disulfide (pPAN/Se2S3) composite cathode is synthesized by deep lithiation to address the above challenges. The Li‐rich molecular structure significantly boosts the lithium storage kinetics by accelerating lithium diffusivity and improving electronic conductivity. Even under practical test conditions requiring a lean electrolyte (Electrolyte/sulfur ratio of 4.1 μL mg−1) and high loading (7 mg cm−2 of pPAN/Se2S3), DL‐pPAN/Se2S3 exhibits a specific capacity of 558 mAh g−1, maintaining 484 mAh g−1 at the 100th cycle with an average Coulombic efficiency of near 100%. Moreover, it provides (electro)chemically stable Li resources to offset Li consumption over charge–discharge cycles. As a result the as‐fabricated anode‐free cell shows a superior cycling stability with 90% retention of the initial capacity over 45 cycles. This study provides a novel approach for fabricating high‐energy and stable Li–SPAN cells. [ABSTRACT FROM AUTHOR]

Background: Central poststroke pain (CPSP) is one of the primary sequelae following stroke, yet its underlying mechanisms are poorly understood. Methods: By lesioning the lateral thalamic nuclei, we first established a CPSP model that exhibits mechanical and thermal hypersensitivity. Innocuous mechanical stimuli following the thalamic lesion evoked robust neural activation in somatosensory corticospinal neurons (CSNs), as well as in the deep dorsal horn, where low threshold mechanosensory afferents terminate. In this study, we used viral‐based mapping and intersectional functional manipulations to decipher the role of somatosensory CSNs and their spinal targets in the CPSP pathophysiology. Results: We first mapped the post‐synaptic spinal targets of lumbar innervating CSNs using an anterograde trans‐synaptic AAV1‐based strategy and showed these spinal interneurons were activated by innocuous tactile stimuli post‐thalamic lesion. Functionally, tetanus toxin‐based chronic inactivation of spinal neurons targeted by CSNs prevented the development of CPSP. Consistently, transient chemogenetic silencing of these neurons alleviated established mechanical pain hypersensitivity and innocuous tactile stimuli evoked aversion linked to the CPSP. In contrast, chemogenetic activation of these neurons was insufficient to induce robust mechanical allodynia typically observed in the CPSP. Conclusion: The CSNs and their spinal targets are required but insufficient for the establishment of CPSP hypersensitivity. Our study provided novel insights into the neural mechanisms underlying CPSP and potential therapeutic interventions to treat refractory central neuropathic pain conditions. [ABSTRACT FROM AUTHOR]

The ever‐growing pursuit of high energy density batteries has triggered extensive efforts toward developing alkali metal (Li, Na, and K) battery (AMB) technologies owing to high theoretical capacities and low redox potentials of metallic anodes. Typically, for new battery systems, the electrolyte design is critical for realizing the battery electrochemistry of AMBs. Conventional electrolytes in alkali ion batteries are generally unsuitable for sustaining the stability owing to the hyper‐reactivity and dendritic growth of alkali metals. In this review, we begin with the fundamentals of AMB electrolytes. Recent advancements in concentrated and fluorinated electrolytes, as well as functional electrolyte additives for boosting the stability of Li metal batteries, are summarized and discussed with a special focus on structure–composition–performance relationships. We then delve into the electrolyte formulations for Na‐ and K metal batteries, including those in which Na/K do not adhere to the Li‐inherited paradigms. Finally, the challenges and the future research needs in advanced electrolytes for AMB are highlighted. This comprehensive review sheds light on the principles for the rational design of promising electrolytes and offers new inspirations for developing stable AMBs with high performance. [ABSTRACT FROM AUTHOR]

Stakeholders of PPP projects may induce opportunistic behaviors in long-term cooperation. Existing studies emphasized the inhibitory effect of trust on opportunistic behaviors, but most of them simplified the trust relationship into a two-subject perspective. From the perspective of social network analysis, this research constructs a network-level trust relationship between the stakeholders of PPP projects. The index analysis of the trust network shows that the PPP project stakeholders have obvious centrality and there are structural holes in the networks. From the perspective of the stakeholder alliance, different forms of alliances differ in the degree, betweenness, and closeness centrality of the trust network. On this basis, the analysis results of different trust network indicators match the corresponding preventive measures of opportunistic behavior, and this research provides comprehensive suggestions for project management. [ABSTRACT FROM AUTHOR]

Intra-organization and inter-organization collaboration and governance are becoming increasingly important for megaprojects. Different stakeholders form intricate links in a network structure. This study explores the role and effect of hybrid governance on complex network projects, such as urban rail transit projects. This included conducting a questionnaire survey with 116 professionals from organizations involved in urban rail transit projects and adopting structural equation modelling to analyze the data. The results analyzed the levels of intra-organization and inter-organization trust under the conditions of power asymmetry and power sharing. A higher level of power asymmetry was associated with lower hybrid governance performance. In contrast, a higher level of power sharing is associated with better hybrid governance performance. The results are generalizable to other projects with complicated organizational and network relationships. [ABSTRACT FROM AUTHOR]

Overexploitation of magnesium has caused serious environmental pollution, and the ecological restoration of magnesite mines has attracted increasing attention in China. The aim of this study was to assess the effects of phytoremediation with Robinia pseudoacacia (RP) on soil quality and microbial communities in magnesite mines. Here, soil samples were collected from restored areas (R. pseudoacacia), natural forest (NF), and unrestored areas (CK), and the soil microbial communities were assessed by Illumina high‐throughput sequencing. Phytoremediation with R. pseudoacacia could alleviate soil alkalization and contribute to the accumulation of soil nutrients. A total of 531,329 effective 16S rRNA and 596,344 valid Internal Transcribed Spacer rRNA gene sequences were obtained, which were classified into 30 bacterial and 12 fungal phyla. The predominant bacterial and fungal phyla were Proteobacteria and Ascomycota, respectively. Bacterial diversity indices of RP were higher than those of the CK, both of which were lower than those in the NF site. While, fungal Chao1 and ACE (abundance‐based coverage estimator) indices of RP were higher than those of the CK and even surpassed those in the NF site. Soil microbial communities significantly differed among different treatments, and the effects of soil factors on microbial communities were comprehensive and not determined by a single factor. Generally, these results indicated that phytoremediation with R. pseudoacacia could effectively improve the soil environment of the abandoned magnesium mine, which provide useful insights and practical references for the suitable species that would be planted on magnesite mine for restoration. [ABSTRACT FROM AUTHOR]

Recently, Jiao and co-workers reported an unprecedented gold-catalyzed nitrogenation of alkynes with trimethylsilyl azide through C-C and C≡C bond cleavages. In this reaction, the acidic additive controls the chemoselectivity for the formation of either carbamides or aminotetrazoles from an internal alkyne. In this study, density functional theory calculations were performed to clarify the mechanism and origin of this chemoselectivity. A systematic search shows that the acidities of CH3SO3H and CF3SO3H determine which of the two reaction pathways is followed and, thus, the chemoselectivity. CH3SO3H favors the hydroxylation step and eventually leads to carbamide production. In contrast, CF3SO3H, which is a stronger acid than CH3SO3H, favors trimethylsilyl removal and eventually generates aminotetrazoles. This acid-dependent chemoselectivity also applies to terminal alkynes and is consistent with the corresponding experimental results. Both CH3SO3H and CF3SO3H form carbamides preferentially because the hydrogen atom in a terminal alkyne promotes nucleophilic hydration more effectively than the n-butyl group in an internal alkyne. [ABSTRACT FROM AUTHOR]

Transition metal oxides hold great promise as high‐energy anodes in next‐generation lithium‐ion batteries. However, owing to the inherent limitations of low electronic/ionic conductivities and dramatic volume change during charge/discharge, it is still challenging to fabricate practically viable compacted and thick TMO anodes with satisfactory electrochemical performance. Herein, with mesoporous cobalt–boride nanoflakes serving as multifunctional bridges in ZnCo2O4 micro‐/nanospheres, a compacted ZnCo2O4/Co–B hybrid structure is constructed. Co–B nanoflakes not only bridge ZnCo2O4 nanoparticles and function as anchors for ZnCo2O4 micro‐/nanospheres to suppress the severe volume fluctuation, they also work as effective electron conduction bridges to promote fast electron transportation. More importantly, they serve as Li+ transfer bridges to provide significantly boosted Li+ diffusivity, evidenced from both experimental kinetics analysis and density functional theory calculations. The mesopores within Co–B nanoflakes help overcome the large Li+ diffusion barriers across 2D interfaces. As a result, the ZnCo2O4/Co–B electrode delivers high gravimetric/volumetric/areal capacities of 995 mAh g−1/1450 mAh cm−3/5.10 mAh cm−2, respectively, with robust rate capability and long‐term cyclability. The distinct interfacial design strategy provides a new direction for designing compacted conversion‐type anodes with superior lithium storage kinetics and stability for practical applications. A compacted Co–B/ZnCo2O4 hybrid structure is constructed with Co–B nanoflakes serving as multifunctional bridges in ZnCo2O4 micro‐/nanospheres. They not only act as robust mechanical bridges to buffer the severe volume fluctuation but also work as ionic/electronic conduction bridges to accelerate the lithium storage kinetics. Compacted and thick electrodes can be fabricated with robust rate capability and long‐term cyclability. [ABSTRACT FROM AUTHOR]

The article presents chemical equation for the article "Copper-Mediated C(sp 3 )-H Azidation with Me3SiN3 : Synthesis of Imidazoles from Ketones and Aldehydes" by Z. Xie and others, published in the journal "Chemical Communications" in 2016.