Glioblastoma (GBM) is an incurable and highly heterogeneous brain tumor, originating from human neural stem/progenitor cells (hNSCs/hNPCs) years ahead of diagnosis. Despite extensive efforts to characterize hNSCs and end-stage GBM at bulk and single-cell levels, the de novo gliomagenic path from hNSCs is largely unknown due to technical difficulties in early-stage sampling and preclinical modeling. Here, we established two highly penetrant hNSC-derived malignant glioma models, which resemble the histopathology and transcriptional heterogeneity of human GBM. Integrating time-series analyses of whole-exome sequencing, bulk and single-cell RNA-seq, we reconstructed gliomagenic trajectories, and identified a persistent NSC-like population at all stages of tumorigenesis. Through trajectory analyses and lineage tracing, we showed that tumor progression is primarily driven by multi-step transcriptional reprogramming and fate-switches in the NSC-like cells, which sequentially generate malignant heterogeneity and induce tumor phenotype transitions. We further uncovered stage-specific oncogenic cascades, and among the candidate genes we functionally validated C1QL1 as a new glioma-promoting factor. Importantly, the neurogenic-to-gliogenic switch in NSC-like cells marks an early stage characterized by a burst of oncogenic alterations, during which transient AP-1 inhibition is sufficient to inhibit gliomagenesis. Together, our results reveal previously undercharacterized molecular dynamics and fate choices driving de novo gliomagenesis from hNSCs, and provide a blueprint for potential early-stage treatment/diagnosis for GBM.

Electrocatalytic nitrogen reduction reaction (NRR) is a promising alternative to the traditional Haber-Bosch process. However, the sluggish kinetics and competitive hydrogen evolution reaction result in poor NH 3 yield and low Faradaic efficiency (FE). Herein, single bismuth atoms incorporated hollow titanium nitride nanorods encapsulated in nitrogen-doped carbon layer (NC) supported on carbon cloth (NC/Bi SAs/TiN/CC) is constructed for electrocatalytic NRR. Impressively, as an integrated electrode, it exhibits a superior ammonia yield rate of 76.15 μg mg cat −1 h −1 (9859 μg 𝝁mol Bi −1 h −1 ) at −0.8 V versus RHE and a high FE of 24.60% at −0.5 V versus RHE in 0.1 m Na 2 SO 4 solution, which can retain stable performance in 10 h continuous operation, surpassing the overwhelming majority of reported Bi-based NRR catalysts. Coupling various characterizations with theory calculations, it is disclosed that the unique monolithic core-shell configuration with porous structure endows abundant accessible active sites, outstanding charge-transfer property, and good stability, while the cooperation effect of Bi SAs and TiN can simultaneously promote the hydrogenation of N 2 into NH 3 * on the TiN surface and the desorption of NH 3 * to release NH 3 on the Bi SA sites. These features result in the significant promotion of NRR performance.

Membrane-based gas separation exhibits many advantages over other conventional techniques; however, the construction of membranes with simultaneous high selectivity and permeability remains a major challenge. Herein, (LDH/FAS)n-PDMS hybrid membranes, containing two-dimensional sub-nanometre channels were fabricated via self-assembly of unilamellar layered double hydroxide (LDH) nanosheets and formamidine sulfinic acid (FAS), followed by spray-coating with a poly(dimethylsiloxane) (PDMS) layer. A CO2 transmission rate for (LDH/FAS)25-PDMS of 7748 GPU together with CO2 selectivity factors (SF) for SF(CO2/H2), SF(CO2/N2) and SF(CO2/CH4) mixtures as high as 43, 86 and 62 respectively are observed. The CO2 permselectivity outperforms most reported systems and is higher than the Robeson or Freeman upper bound limits. These (LDH/FAS)n-PDMS membranes are both thermally and mechanically robust maintaining their highly selective CO2 separation performance during long-term operational testing. We believe this highly-efficient CO2 separation performance is based on the synergy of enhanced solubility, diffusivity and chemical affinity for CO2 in the sub-nanometre channels.

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attractive application potentials as battery-type anodes. [2] Heteroatom doping as one of the most popular strategies has improved Li-ion diffusion kinetics of carbons. [3] However, the dopants are mainly limited to nonmetal heteroatoms, such as N, S, and P. In fact, theoretical simulations suggested that, compared with nonmetal doping, doping of single atomic metals (SAMs) in carbon can better increase adsorption energy, decrease diffusion energy barriers, and exceptionally improve storage capacity. [4] Additionally, experimental investigations show that SAMs in carbon networks are usually coordinated by nonmetal atoms such as N, O, P, and C, [5,6] so SAMs together with their coordination atoms are just like atomic-scale metal compounds such as oxide, nitride, phosphide, and carbide. These metal compounds, especially nanosized ones composited with carbon, are well-known highly active Li-ion storage materials. [7] In the SAM-doped carbon, atomic-scale metal compounds are expected to own higher activity than those nanosized ones due to atomic interface interaction between SAMs and carbon. [6,8] Therefore, doping of SAMs will be a new pathway to design amazing carbon anodes for LICs. Carbon-supported SAMs have exhibited promising application in various catalysis fields. [5,9] Nevertheless, application of SAMs in LICs has not yet been carried out. Pyrolysis using organic precursors and metal compounds as sources is one of the most popular methods to synthesize SAM-doped carbon. [5,9a] During pyrolysis, heteroatoms of organic precursors are converted to nonmetal anchoring sites to stabilize metal atoms. Metal atoms are apt to aggregate due to high surface energy. Various strategies have been employed to suppress metal aggregation such as spatial confinement, [10] Zn-evaporation, [11] constraint of uncoordinated groups, [12] and polymer encapsulation. [13] However, these efforts mainly focus on the static modulation on the organic precursors and metal sources. In fact, evolution of metal atoms and anchoring sites during pyrolysis is a dynamic process. [13c] On the one hand, migration of metal atoms becomes more active at high temperature. On the other hand, nonmetal anchoring sites are not static but dramatically decreased by pyrolysis. Limited anchoring sites are not enough to support high loading of SAMs. The mass content of SAMs is generally less than 1.5 wt%, [5d] which is still Carbon-supported single atomic metals (SAMs) have attracted great interest in energy research. However, it is still a great challenge to control the content of SAMs in carbon. In this work, a dynamic inhibition strategy is proposed to achieve content-controllable synthesis of Cu atoms loaded in carbon nanofibers (CNFs) using polyacrylonitrile (PAN) and Cu(NO 3) 2 as precursors by electrospinning. Interestingly, N-anchoring sites in PAN-derived carbon matrix are dynamically increased to inhibit the aggregation of Cu atoms. Therefore, Cu atom content can be linearly controlled by adjusting the ratio of Cu(NO 3) 2 /PAN, and a high mass conten...

Inorganic–organic hybrid films containing two‐dimensional nanosheets have shown good gas barrier performance, but moderate tensile property, because of the rigid characteristics of covalent or ionic bonds between the assembly units. In this work, we used LDH nanosheets rich in hydroxyl groups as building units, followed by modification of tannic acid (TA), to assemble with polyethylene oxide (PEO) through hydrogen bonds. Compared with previous work, the tensile property and oxygen barrier performance of (TA@LDH/PEO)n films have been significantly improved. A 50‐bilayer TA@LDH/PEO film, deposited on a 1 mm thick natural rubber substrate, results in a 29× reduction (contrast with bare substrate) in oxygen transmission rate and maintains its good barrier property even under a large elongation of 120%. The excellent tensile and gas barrier properties are attributed to the ductility of hydrogen bond network among building blocks and the significant prolongation of oxygen transmission path induced by LDH nanosheets.

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