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Atomic-level coordination engineering is an efficient strategy for tuning the catalytic performance of single-atom catalysts (SACs). However, their rational design has so far been plagued by the lack of a universal correlation between the coordination symmetry and catalytic properties. Herein, we synthesised planar-symmetry-broken CuN 3 (PSB-CuN 3 ) SACs through microwave heating for electrocatalytic CO 2 reduction. Remarkably, the as-prepared catalysts exhibited a selectivity of 94.3% towards formate at −0.73 V vs. RHE, surpassing the symmetrical CuN 4 catalyst (72.4% at −0.93 V vs. RHE). In a flow cell equipped with a PSB-CuN 3 electrode, over 90% formate selectivity was maintained at an average current density of 94.4 mA cm −2 during 100 h operation. By combining definitive structural identification with operando X-ray spectroscopy and theoretical calculations, we revealed that the intrinsic local symmetry breaking from planar D 4 h configuration induces an unconventional dsp hybridisation, and thus a strong correlation between the catalytic activity and microenvironment of metal centre (i.e., coordination number and distortion), with high preference for formate production in CuN 3 moiety. The finding opens an avenue for designing efficient SACs with specific local symmetries for selective electrocatalysis. Atomic-level coordination influences the properties of single-atom-catalysts but is difficult to precisely engineer. Here, authors study the role of local symmetry manipulation, finding planar-symmetry-broken CuN 3 catalysts outperform highly symmetrical CuN 4 for CO 2 electroreduction to formic acid.

Seawater electrolysis offers a renewable, scalable, and economic means for green hydrogen production. However, anode corrosion by Cl - pose great challenges for its commercialization. Herein, different from conventional catalysts designed to repel Cl - adsorption, we develop an atomic Ir catalyst on cobalt iron layered double hydroxide (Ir/CoFe-LDH) to tailor Cl - adsorption and modulate the electronic structure of the Ir active center, thereby establishing a unique Ir-OH/Cl coordination for alkaline seawater electrolysis. Operando characterizations and theoretical calculations unveil the pivotal role of this coordination state to lower OER activation energy by a factor of 1.93. The Ir/CoFe-LDH exhibits a remarkable oxygen evolution reaction activity (202 mV overpotential and TOF = 7.46 O 2 s −1 ) in 6 M NaOH+2.8 M NaCl, superior over Cl - -free 6 M NaOH electrolyte (236 mV overpotential and TOF = 1.05 O 2 s −1 ), with 100% catalytic selectivity and stability at high current densities (400-800 mA cm −2 ) for more than 1,000 h. The seawater oxidation reaction faces challenges from competitive chloride oxidation reaction. Herein, the authors have utilized chlorine adsorption to modulate the single-atom Ir coordination state and promote seawater oxidation and catalyst stability.

Pressure-induced charge density wave (CDW) state can overcome the low-temperature limitation for practical application, thus seeking its traces in experiments is of great importance. Herein, we provide spectroscopic evidence for the emergence of room temperature CDW order in the narrow pressure range of 10–15 GPa in bulk VSe 2 . Moreover, we discovered an 8-coordination structure of VSe 2 with C2/m symmetry in the pressure range of 35–65 GPa by combining the X-ray absorption spectroscopy, X-ray diffraction experiments, and the first-principles calculations. These findings are beneficial for furthering our understanding of the charge modulated structure and its behavior under high pressure.

Inhibitors of cyclin-dependent kinases (Cdks) have been reported to have activities in many types of cancer cells by inhibiting Cdk7 and Cdk9, which control transcription. SNS-032 is a potent and selective inhibitor of Cdk2, Cdk7 and Cdk9 and has emerged in clinical trials. Here, we examined the viability of MCF-7 and MDA-MB-435 breast cancer cells in the presence of SNS-032 and observed a dose-dependent inhibition of cellular proliferation in both cell lines. SNS-032 had a direct apoptosis-inducing effect through both the extrinsic and intrinsic apoptotic pathways in breast cancer cells as shown by a dose-dependent increase in Annexin V-positive cells and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells, as well as activation of caspase-8, -9 and poly(ADP-ribose) polymerase (PARP). At the molecular level, SNS-032 induced a marked dephosphorylation of serine 2 and 5 of RNA polymerase (RNA Pol) II and blocked RNA synthesis. Consistent with the inherently rapid turnover rates of their transcripts and proteins, the anti-apoptotic proteins Mcl-1 and X-linked inhibitor of apoptosis protein (XIAP) were rapidly reduced on exposure to SNS-032. Our results also indicated that SNS-032 suppressed the growth of breast cancer xenografts in mice. These data demonstrate that the use of SNS-032 may be a rational and novel therapeutic strategy for human breast cancer and warrants further clinical investigation.

Residual antibiotics can enter soil and water bodies through organic fertilizers with food safety risk via plants absorption, while how do plant growth and quinolone accumulation respond to residual antibiotics levels in soil or water is not clear. Hydroponic experiment in greenhouse was conducted with floating seedlings of tobacco as model plant to investigate the responses of quinolone antibiotics accumulation and plant growth to different levels of ciprofloxacin (CIP) and norfloxacin (NOR). Results showed that CIP and NOR inhibited the growth of tobacco seedlings. The plant height, stem circumference, maximum leaf width, and maximum leaf area of tobacco seedlings were significantly decreased. So as to the plant biomass of leaves, stems, and roots. Accumulation of CIP in the tobacco seedlings in the T3 was 1.1 times that of the tobacco seedlings in the T1, NOR in the T4 was 1.2 times that of the tobacco seedlings in the T1. And the higher the concentration, the more significant the inhibitory effect. Both antibiotics can be absorbed and accumulated by tobacco seedlings. Additionally, the inhibitory effect of CIP was greater than that of NOR.