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Photocatalytic conversion of CO 2 into syngas is highly appealing, yet still suffers from the undesirable product yield due to the sluggish carrier transfer and the uncontrollable affinity between catalytic sites and intermediates. Here we report the fabrication of Co sites with tunable electron localization capability on two dimensional (2D) nanosheets assembled three dimensional (3D) ordered macroporous framework (3DOM-NS). The as-prepared Co-based 3DOM-NS catalysts exhibit attractive photocatalytic performances toward CO 2 reduction, among which the cobalt sulfide one (3DOM Co-SNS) shows the highest syngas generation rate up to 347.3 μmol h −1 under the irradiation of visible light and delivers a remarkable catalytic activity (1150.7 μmol h −1 ) in a flow reaction system under natural sunlight. Mechanism studies reveal that the high electron localization of metal sites in 3DOM Co-SNS strengthens the interaction between Co and HCOO* via the orbital interactions of d yz / d xz - p and s - s , thus facilitating the cleaving process of C-O bond. Additionally, the ordered macroporous framework with nanosheet subunits elevates the transfer efficiency of photoexcited electrons, which contributes to its high activity. Efficient photocatalytic conversion of CO 2 into syngas is a promising but challenging technology. Here, the authors report a phase transformation method to produce Co sites with tunable electron localization on multi-dimensional architecture framework that can improve the syngas evolution kinetics.

Single-atom (SA) catalysts provide extensive possibilities in pursuing fantastic catalytic performances, while their preparation still suffers from metal aggregation and pore collapsing during pyrolysis. Here we report a versatile medium-induced infiltration deposition strategy for the fabrication of SAs and hetero-SAs (M a N 4 /M b N 4 @NC; M a  = Cu, Co, Ni, Mn, M b  = Co, Cu, Fe, NC = N-doped carbon). In-situ and control experiments reveal that the catalyst fabrication relies on the “step-by-step” evolution of M a -containing metal-organic framework (MOF) template and M b -based metal precursor, during which molten salt acts as both pore generator in the MOF transformation, and carrier for the oriented infiltration and deposition of the latter to eventually yield metal SAs embedded on hierarchically porous support. The as-prepared hetero-SAs show excellent catalytic performances in the general synthesis of 33 kinds of natural flavones. The highly efficient synthesis is further strengthened by the reliable durability of the catalyst loaded in a flow reactor. Systematic characterizations and mechanism studies suggest that the superior catalytic performances of CuN 4 /CoN 4 @NC are attributed to the facilitated O 2 activating-splitting process and significantly reduced reaction energy barriers over CoN 4 due to the synergetic interactions of the adjacent CuN 4 . The preparation of single-atom catalysts still suffers from metal aggregation and pore collapsing during pyrolysis. Here the authors report a versatile medium-induced infiltration deposition strategy for the fabrication of a series of single-atom and hetero-single-atom catalysts.

The diffusion limitations on gas storage and catalytic reaction of microporous materials can often be overcome if they are incorporated into a mesoporous structure with much larger pores. Shen et al. grew ordered arrays of microcrystals of the ZIF-8 metal-organic framework, in which zinc ions are bridged by 2-methylimidazole linkers, inside a porous polystyrene template. These materials showed higher reaction rates for the Knoevenagel reaction between benzaldehydes and malononitriles and better catalyst recyclability. Science , this issue p. 206 A double-solvent method and templating are used to grow ordered arrays of metal-organic framework microcrystals. We constructed highly oriented and ordered macropores within metal-organic framework (MOF) single crystals, opening up the area of three-dimensional–ordered macro-microporous materials (that is, materials containing both macro- and micropores) in single-crystalline form. Our methodology relies on the strong shaping effects of a polystyrene nanosphere monolith template and a double-solvent–induced heterogeneous nucleation approach. This process synergistically enabled the in situ growth of MOFs within ordered voids, rendering a single crystal with oriented and ordered macro-microporous structure. The improved mass diffusion properties of such hierarchical frameworks, together with their robust single-crystalline nature, endow them with superior catalytic activity and recyclability for bulky-molecule reactions, as compared with conventional, polycrystalline hollow, and disordered macroporous ZIF-8.

Gallic acid is an active phenolic acid widely distributed in plants, and there is compelling evidence to prove its anti-inflammatory effects. NLRP3 inflammasome dysregulation is closely linked to many inflammatory diseases. However, how gallic acid affects the NLRP3 inflammasome remains unclear. Therefore, in the present study, we investigated the mechanisms underlying the effects of gallic acid on the NLRP3 inflammasome and pyroptosis, as well as its effect on gouty arthritis in mice. The results showed that gallic acid inhibited lactate dehydrogenase (LDH) release and pyroptosis in lipopolysaccharide (LPS)-primed and ATP-, nigericin-, or monosodium urate (MSU) crystal-stimulated macrophages. Additionally, gallic acid blocked NLRP3 inflammasome activation and inhibited the subsequent activation of caspase-1 and secretion of IL-1β. Gallic acid exerted its inhibitory effect by blocking NLRP3-NEK7 interaction and ASC oligomerization, thereby limiting inflammasome assembly. Moreover, gallic acid promoted the expression of nuclear factor E2-related factor 2 (Nrf2) and reduced the production of mitochondrial ROS (mtROS). Importantly, the inhibitory effect of gallic acid could be reversed by treatment with the Nrf2 inhibitor ML385. NRF2 siRNA also abolished the inhibitory effect of gallic acid on IL-1β secretion. The results further showed that gallic acid could mitigate MSU-induced joint swelling and inhibit IL-1β and caspase 1 (p20) production in mice. Moreover, gallic acid could moderate MSU-induced macrophages and neutrophils migration into joint synovitis. In summary, we found that gallic acid suppresses ROS generation, thereby limiting NLRP3 inflammasome activation and pyroptosis dependent on Nrf2 signaling, suggesting that gallic acid possesses therapeutic potential for the treatment of gouty arthritis.

Single cluster catalysts (SCCs) are considered as versatile boosters in heterogeneous catalysis due to their modifiable single cluster sites and supports. In this work, we report subnanometric Cu clusters dispersed on Fe-doped MoO 2 support for biomass-derived furfural upgrading. Systematical characterizations suggest uniform Cu clusters (composing four Cu atoms in average) are homogeneously immobilized on the atomically Fe-doped ultrafine MoO 2 nanocrystals (Cu 4 /Fe 0.3 Mo 0.7 O 2 @C). The atomic doping of Fe into MoO 2 leads to significantly modified electronic structure and consequently charge redistribution inside the supported Cu clusters. The as-prepared Cu 4 /Fe 0.3 Mo 0.7 O 2 @C shows superior catalytic performance in the oxidative coupling of furfural with C 3 ~C 10 primary/secondary alcohols to produce C 8 ~C 15 aldehydes/ketones (aviation biofuel intermediates), outperforming the conventionally prepared counterparts. DFT calculations and control experiments are further carried out to interpret the structural and compositional merits of Cu 4 /Fe 0.3 Mo 0.7 O 2 @C in the oxidative coupling reaction, and elucidate the reaction pathway and related intermediates. Single cluster catalysts are considered as versatile boosters in heterogeneous catalysis. Here the authors report subnanometric Cu clusters dispersed on Fe-doped MoO 2 support exhibits attractive performance in furfural valorization to C8-C15 aviation biofuels via a newly developed reaction route.

Quasi-one-dimensional covalent organic frameworks have emerged as promising platforms for photochemical energy conversion due to their low density of basal sites, abundant edge sites, and dual-chain-like structure. However, the development of quasi-one-dimensional covalent organic frameworks in photocatalysis is still highly hindered by their limited linkage chemistry. Herein, we report an enaminone-linked quasi-one-dimensional covalent organic framework. The polar enaminone bonds together with dual-chain-like structure endow enaminone-linked quasi-one-dimensional covalent organic framework with broad light adsorption and effective excitonic dissociation abilities. Significantly, a high CO yield of 3045 μmol g -1 with approximately 100% selectivity was achieved in a 24 h reaction under gas-solid conditions. More interestingly, the hydrogen atom on nitrogen site in enaminone bond could assist in the activation of CO 2 molecule via hydrogen-bond interaction. This interaction leads to the strongest adsorption ability for CO 2 and the lowest energy barrier for the rate-determining step during CO 2 reduction over enaminone-linked quasi-one-dimensional covalent organic framework compared to those over mixture-linked quasi-one-dimensional covalent organic framework and imine-linked quasi-one-dimensional covalent organic framework counterparts. All of these factors directly contribute to the enhanced activity of enaminone-linked quasi-one-dimensional covalent organic framework in the photocatalytic CO 2 reduction to CO. This study reports a new kind of En-Q1DCOF. The polar enaminone bonds and dual-chain-like structure endow En-Q1DCOF excellent photoelectric conversion performance. Furthermore, the N-site H atom in enaminone facilitates CO₂ activation via H-bonding.

Direct conversion of CH 4 into liquid oxygenates under mild conditions is of great significance but remains challenging due to the high dissociation energy of inert C-H bond. Here we report the fabrication of a dual atomic Fe and Pd catalyst with periodic macroporous structure (Fe 1 -Pd 1 OMNC) toward the direct CH 4 conversion at room temperature. Mechanism studies reveal that a charge polarization region (O δ− -Fe-Pd δ+ ) is formed in-situ on Fe-Pd atomic sites upon oxidant activation, wherein the electron-rich O δ⁻ and electron-deficient Pd δ+ regions can respectively capture the H δ⁺ and CH 3 δ⁻ in CH 4 and lead to the activation of C-H bond. As a result, Fe 1 -Pd 1 OMNC demonstrates attractive photothermal catalytic performance toward the selective oxidation of CH 4 under Xe lamp irradiation, achieving the productivities of C1 oxygenates as high as 0.754 mmol h −1 and 0.035 mmol h −1 when using H 2 O 2 or O 2 as the oxidant, respectively. This work reports a catalyst with atomically dispersed Fe and Pd dual sites for photothermal catalytic CH 4 oxidation, and demonstrates that the in-situ formation of charge-polarized regions can induce the polarization and cleavage of C-H bonds.

Dysregulated alternative splicing has been closely linked to the initiation and progression of tumors. Nevertheless, the precise molecular mechanisms through which splicing factors regulate endometrial cancer progression are still not fully understood. This study demonstrated elevated expression of the splicing factor SNRPB in endometrial cancer samples. Furthermore, our findings indicate that high SNRPB expression is correlated with poor prognosis in patients with endometrial cancer. Functionally, SNRPB inhibition hindered the proliferative and metastatic capacities of endometrial cancer cells. Mechanistically, we revealed that SNRPB knockdown decreased POLD1 expression and that POLD1 intron 22 was retained after SNRPB silencing in endometrial cancer cells, as determined via RNA sequencing data analysis. The retained intron 22 of POLD1 created a premature termination codon, leading to the absence of amino acids 941–1,107 and the loss of the site of interaction with PCNA, which is essential for POLD1 enzyme activity. In addition, POLD1 depletion decreased the increase in the malignancy of endometrial cancer cells overexpressing SNRPB. Furthermore, miR-654-5p was found to bind directly to the 3′ untranslated region of SNRPB, resulting in SNRPB expression inhibition in endometrial cancer. Antisense oligonucleotide-mediated SNRPB inhibition led to a decrease in the growth capacity of a cell-derived xenograft model and a patient with endometrial cancer-derived xenograft model. Overall, SNRPB promotes the efficient splicing of POLD1 by regulating intron retention, ultimately contributing to high POLD1 expression in endometrial cancer. The oncogenic SNRPB–POLD1 axis is an interesting therapeutic target for endometrial cancer, and antisense oligonucleotide-mediated silencing of SNRPB may constitute a promising therapeutic approach for treating patients with endometrial cancer. Targeting SNRPB offers new hope for endometrial cancer Endometrial cancer is a common cancer in women, with rising cases linked to obesity. This study focuses on a protein called SNRPB, which is involved in RNA splicing. SNRPB is found in high levels in endometrial cancer and is linked to poor outcomes. Researchers used various methods, including bioinformatics and lab experiments, to study SNRPB’s role. They found that reducing SNRPB levels slowed cancer cell growth and spread. They also discovered that SNRPB affects another protein, POLD1, which is important for DNA replication and repair. Lowering SNRPB led to changes in POLD1 that hindered cancer progression. This study suggests that targeting SNRPB with antisense oligonucleotides, which are short DNA or RNA molecules designed to block specific genes, could be a promising treatment strategy. This approach could lead to new therapies for endometrial cancer in the future. This summary was initially drafted using artificial intelligence, then revised and fact-checked by the author.

A Cu-PP hydrogel with 3D network was synthesized using a simple in-situ polymerization method. PA (phytic acid) acts as the dopants and crosslinking agent to form PANI-PA (polyaniline-phytic acid) hydrogel via in-situ polymerization of aniline. PA is also used as a chelating agent to coordinate with Cu2+ ion due to the high coordination capacity. When irradiated by light, Cu2+ was slowly reduced to form Cu NPs, distributing uniformly in the 3D matrix of PANI-PA. The 3D network nanostructure ensures a complete contact between the photocatalyst and water, promoting the separation of electrons and holes. The introduction of PANI-PA improves the separation efficiency of electron-hole pairs, where PANI-PA acts as a hole reservoir to trap the holes generated by Cu NPs, hindering the recombination of electron-hole pairs. The Cu0.2-PP hydrogel with a copper content of 30.8% exhibits the best hydrogen production rate (6.09 mmol·g−1·h−1), which is 6.7 times greater than that of pure Cu NPs.

Gold-copper alloys have rich forms. Here we report an atomically resolved [Au 52 Cu 72 ( p -MBT) 55 ] + Cl − nanoalloy ( p -MBT = SPh- p -CH 3 ). This nanoalloy exhibits unusual structural patterns. First, two Cu atoms are located in the inner 7-atom decahedral kernel (M 7 , M = Au/Cu). The M 7 kernel is then enclosed by a second shell of homogold (Au 47 ), giving rise to a two-shelled M 54 (i.e. Au 52 Cu 2 ) full decahedron. A comparison of the non-truncated M 54 decahedron with the truncated homogold Au 49 kernel in similar-sized gold nanoparticles provides for the first time an explanation for Marks decahedron truncation. Second, a Cu 70 (SR) 55 exterior cage resembling a 3D Penrose tiling protects the M 54 decahedral kernel. Compared to the discrete staple motifs in gold:thiolate nanoparticles, the Cu-thiolate surface of Au 52 Cu 72 forms an extended cage. The Cu-SR Penrose tiling retains the M 54 kernel’s high symmetry ( D 5h ). Third, interparticle interactions in the assembly are closely related to the symmetry of the particle, and a “quadruple-gear-like” interlocking pattern is observed. The formation of Marks truncated decahedra in nanoparticles is ubiquitous but the mechanism has not been fully understood. Here, the authors provide atomic-level insights by creating a non-truncated Au 52 Cu 72 (SR) 55 decahedral nanocluster and comparing it with the truncated homogold decahedra.