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While the mild production of syngas (a mixture of H2 and CO) from CO2 and H2O is a promising alternative to the coal‐based chemical engineering technologies, the inert nature of CO2 molecules, unfavorable splitting pathways of H2O and unsatisfactory catalysts lead to the challenge in the difficult integration of high CO2 conversion efficiency with produced syngas with controllable H2/CO ratios in a wide range. Herein, we report an efficient plasma‐driven catalytic system for mild production of pure syngas over porous metal–organic framework (MOF) catalysts with rich confined H2O molecules, where their syngas production capacity is regulated by the in situ evolved ligand defects and the plasma‐activated intermediate species of CO2 molecules. Specially, the Cu‐based catalyst system achieves 61.9 % of CO2 conversion and the production of pure syngas with wide H2/CO ratios of 0.05 : 1–4.3 : 1. As revealed by the experimental and theoretical calculation results, the in situ dynamic structure evolution of Cu‐containing MOF catalysts favors the generation of coordinatively unsaturated metal active sites with optimized geometric and electronic characteristics, the adsorption of reactants, and the reduced energy barriers of syngas‐production potential‐determining steps of the hydrogenation of CO2 to *COOH and the protonation of H2O to *H. [ABSTRACT FROM AUTHOR]

Background: Benzene and its metabolite hydroquinone (HQ) are widely used in daily life, and long‐term exposure to benzene or HQ can induce acute myeloid leukemia (AML). Circular RNAs (circRNAs) are mostly produced by reverse splicing of gene exon mRNA precursors. The modulation of circRNA expression is connected to leukemia progression; however, the molecular mechanism is still unknown. Materials and methods: In this study, the cells were divided into four groups: PBS control group (PBS‐TK6), TK6 malignantly transformed cells induced by 10.0 μmol/L HQ (HQ‐TK6), and HQ‐TK6 cells treated with 5 μmol/L 5‐AzaC (DNA methyltransferase inhibitor) for 24 h (HQ + 5‐AzaC). HQ‐TK6 cells were treated with 200 nmol/L TSA (histone deacetylation inhibitor) for 24 h (HQ + TSA). qRT–PCR was used to identify the differential hsa_circ_401351 expression between the four groups. We further determined the hsa_circ_401351 promoter methylation level with methylation‐specific PCR. DNMT1 and DNMT3b were knocked down by CRISPR/Cas9 to elucidate the specific molecular mechanism of hsa_circ_401351 in HQ‐TK6 cells. CCK‐8 and flow cytometry detected cell proliferation and apoptosis, respectively, after hsa_circ_401351 was overexpressed in HQ‐TK6 cells. Results: Compared with the PBS‐TK6 group, the expression of hsa_circ_401351 was found to be lower in the HQ‐TK6 group. Nevertheless, treatment with 5‐AzaC or TSA increased hsa_circ_401351 expression, with the upregulation being more pronounced in the TSA group. The expression of hsa_circ_401351 in the DNMT1 knockdown group was dramatically increased by 50% compared to that in the control group, and the DNA methylation level of the hsa_circ_401351 promoter region was decreased. When hsa_circ_401351 was overexpressed, HQ‐TK6 cell proliferation was significantly slowed after 48 h compared with the control group. Flow cytometry showed that cells were mainly arrested in G1 phase, and apoptosis was significantly enhanced. Similarly, qRT–PCR and Western blot data showed significant reductions in Caspase‐3 mRNA and protein production, and Bcl‐2 mRNA levels were also elevated. Conclusions: Overall, our research showed that elevated DNMT1 expression in HQ‐TK6 cells increased methylation levels and decreased expression of the hsa_circ_401351 promoter region, limiting its ability to suppress HQ‐TK6 cell growth and enhance apoptosis. [ABSTRACT FROM AUTHOR]

Local officials play active and important roles in the high-quality agricultural development process in China. In this study, the DEA-SBM model was used to measure the level of agricultural quality development in China, and Tobit regression was conducted to analyze the impacts of officials on agricultural quality development in China. The results showed that between 1997 and 2016, the agricultural GTFP exhibited a downward trend before following an upward trend in China. The personal characteristics of officials had important effects on the development of agricultural quality. In different development stages, officials had diverse effects on agricultural quality development.

Hydroquinone (HQ), one of the main active metabolites of benzene, can induce the abnormal expression of long non-coding RNA (lncRNA). Studies have shown that lncRNA plays an important role in the occurrence of hematologic tumors induced by benzene or HQ. However, the molecular mechanism remains to be elucidated. Here, we investigated the molecular mechanism by which poly(ADP-ribose)polymerase 1 (PARP-1) interacts with DNA methyltransferase 1 (DNMT1) to regulate promoter methylation mediated linc01132 expression in HQ-induced TK6 malignant transformed cells (HQ-MT). The results revealed that the expression of linc01132 was increased in benzene-exposed workers and HQ-MT cells. The methylation of linc01132 promoter region was inhibited. Furthermore, in HQ-MT cells treated with 5-Aza-2′-deoxycytidine (5-AzaC) (DNA methyltransferase inhibitor) or trichostatin A (TSA) (histone deacetylation inhibitor), the expression of linc01132 was increased due to the regulation of DNA promoter methylation level by inhibiting DNMT1 expression. The methylation level of linc01132 promoter was correlated negatively with the expression of linc01132 in benzene-exposed workers, indicating that DNA methylation may contribute the expression of linc01132. Knockout of DNMT1, not DNMT3b, increased the expression of linc01132 as well as the demethylation of linc01132 promoter in HQ-MT cells. It was found that by knockdown PARP-1, the expression of DNMT1 in the nucleus was increased by immunofluorescence confocal microscopy, leading to the inhibition of hypermethylation in the promoter region of linc01132. Therefore, PARP-1 inhibits DNA methyltransferase (DNMT)-mediated promoter methylation and plays a role in linc01132 expression in benzene-exposed workers or HQ-MT cells, and is associated with benzene or HQ induced leukemia progression. [ABSTRACT FROM AUTHOR]

In view of power quality problems of low power factor, voltage dips and flicker of power system caused by impact load, a compensation method of dynamic reactive power with fast thyristor switched capacitor was put forward. The method adopts reactive current detection algorithm based on improved instantaneous reactive power theory and the new type of incomplete differential PID control algorithm to fastly compensate reactive of impact loads. The experimental results show that the method not only can improve power factor of the system, but also can stabilize voltage of the transformer output, enhance control precision and response speed of the system.

T‐acute lymphoblastic leukemia/lymphoma (T‐ALL/LBL) is a malignant neoplasm of immature lymphoblasts. Terminal deoxynucleotidyl transferase (TDT) is a template‐independent DNA polymerase that plays an essential role in generating diversity for immunoglobulin genes. T‐ALL/LBL patients with TDT− have a worse prognosis. However, how TDT− promotes the disease progression of T‐ALL/LBL remains unknown. Here we analyzed the prognosis of T‐ALL/LBL patients in Shanghai Children's Medical Center (SCMC) and confirmed that TDT− patients had a higher rate of recurrence and remission failure and worse outcomes. Cellular experiments demonstrated that TDT was involved in DNA damage repair. TDT knockout delayed DNA repair, arrested the cell cycle and decreased apoptosis to induce the accumulation of chromosomal abnormalities and tolerance to abnormal karyotypes. Our study demonstrated that the poor outcomes in TDT− T‐ALL/LBL might be due to the drug resistance (VP16 and MTX) induced by chromosomal abnormalities. Our findings revealed novel functions and mechanisms of TDT in T‐ALL/LBL and supported that hematopoietic stem cell transplantation (HSCT) might be a better choice for these patients. [ABSTRACT FROM AUTHOR]

To rationally design photocatalysts with high generation rate and selectivity of target product remains an ongoing challenge for CO2 conversion in pure H2O. Herein, from the viewpoint of enhancing the separation efficiency of photoinduced electron‐hole pairs and the adsorption ability of CO2 molecule, we have constructed a series of Z‐scheme defective heterojunctions of BiOBr nanosheets and hollow NH2‐functionalized metal‐organic framework (MOF) MIL‐125 with Ti ions as metal centers (noted as NH2‐MIL‐125(Ti)). Systematic characterization demonstrates that the BiOBr nanosheets are anchored on the surface of hollow NH2‐MIL‐125(Ti), which facilitates the efficient visible‐light‐driven catalytic reduction of CO2 to CO with nearly 100% selectivity by pure H2O. Especially, the CO generation rate of optimized catalyst with oxygen vacancies reaches 459.7 μmol g−1 h−1, which is higher than those of all the previously reported photocatalysts without sacrificial reagents. This approach provides a new insight for using inorganic semiconductors to fabricate semiconducting MOFs for high‐efficiency photocatalytic reduction CO2 into value‐added chemicals by pure H2O. [ABSTRACT FROM AUTHOR]