Decarboxylative C−H functionalization reactions are highly attractive methods for forging carbon–carbon bonds considering their inherent step‐ and atom‐economical features and the pervasiveness of ...carboxylic acids and C−H bonds. An ideal approach to achieve these dehydrogenative transformations is through hydrogen evolution without using any chemical oxidants. However, effective couplings by decarboxylative carbon–carbon bond formation with proton reduction remain an unsolved challenge. Herein, we report an electrophotocatalytic approach that merges organic electrochemistry with photocatalysis to achieve the efficient direct decarboxylative C−H alkylation and carbamoylation of heteroaromatic compounds through hydrogen evolution. This electrophotocatalytic method, which combines the high efficiency and selectivity of photocatalysis in promoting decarboxylation with the superiority of electrochemistry in effecting proton reduction, enables the efficient coupling of a wide range of heteroaromatic bases with a variety of carboxylic acids and oxamic acids. Advantageously, this method is scalable to decagram amounts, and applicable to the late‐stage functionalization of drug molecules.
A broadly applicable electrophotocatalytic method for the direct decarboxylative C−H alkylation and carbamoylation of heteroarenes has been developed. This method combines the advantages of photocatalysis and electrochemistry to enable the functionalization of a broad range of substrates and to allow the decarboxylative C−H functionalization reactions to proceed by H2 evolution, obviating the need for oxidizing reagents and proton acceptors.
This study aims to examine the properties of composites that different carbon materials with different measurements can reinforce. Using a melt compounding method, this study combines polypropylene ...(PP) and graphene nano-sheets (GNs) or carbon fiber (CF) to make PP/GNs and PP/CF conductive composites, respectively. The DSC results and optical microscopic observation show that both GNs and CF enable PP to crystalize at a high temperature. The tensile modulus of PP/GNs and PP/CF conductive composites remarkably increases as a result of the increasing content of conductive fillers. The tensile strength of the PP/GNs conductive composites is inversely proportional to the loading level of GNs. Containing 20 wt% of GNs, the PP/GNs conductive composites have an optimal conductivity of 0.36 S/m and an optimal EMI SE of 13 dB. PP/CF conductive composites have an optimal conductivity of 10−6 S/m when composed of no less than 3 wt% of CF, and an optimal EMI SE of 25 dB when composed of 20 wt% of CF.
The methyltransferase like 3 （METTL3）-containing methyltransferase complex catalyzes the N6-methyladenosine （m6A） formation, a novel epitranscriptomic marker; however, the nature of this complex ...remains largely unknown. Here we report two new components of the human m6A methyltransferase complex, Wilms＇ tumor 1-associating protein （WTAP） and methyltransferase like 14 （METTL14）. WTAP interacts with METTL3 and METTL14, and is required for their localization into nuclear speckles enriched with pre-mRNA processing factors and for catalytic ac- tivity of the m6A methyltransferase in vivo. The majority of RNAs bound by WTAP and METTL3 in vivo represent mRNAs containing the consensus m6A motif. In the absence of WTAP, the RNA-binding capability of METTL3 is strongly reduced, suggesting that WTAP may function to regulate recruitment of the m6A methyltransferase complex to mRNA targets. Furthermore, transcriptomic analyses in combination with photoactivatable-ribonucleoside-en- hanced crosslinking and immunoprecipitation （PAR-CLIP） illustrate that WTAP and METTL3 regulate expression and alternative splicing of genes involved in transcription and RNA processing. Morpholino-mediated knockdown targeting WTAP and/or METTL3 in zebrafish embryos caused tissue differentiation defects and increased apoptosis. These findings provide strong evidence that WTAP may function as a regulatory subunit in the m6A methyltransferase complex and play a critical role in epitranscriptomic regulation of RNA metabolism.
Aim
To explore whether WeChat platform‐based treatment of women with gestational diabetes mellitus (GDM) reduces the risk of perinatal complications and explore factors affecting gestational age at ...delivery.
Methods
Pregnant women with GDM (n = 107) and normal glucose tolerance (n =50, group C) according to oral glucose tolerance test (OGTT) results during gestational weeks 24–28 were included. Women with GDM were divided into groups A (n =57) and B (n =50) according to informed consent. According to GDM treatment norms, group B was given routine outpatient treatment and health education guidance. In addition to the interventions in group B, group A was given access to both a smartphone‐based telemedicine system and articles providing continuous health education. The PBG level in groups A and B was compared, as were differences in maternal and fetal outcomes. Data were analyzed by t‐test, analysis of variance (anova), chi‐square test and multiple linear regression, with P < 0.05 considered significant.
Results
Fasting blood glucose (FBG) and 2‐h postprandial blood glucose (PBG) were significantly lower and premature delivery was significantly less likely in group A than in group B (all P < 0.05). Compared with group B, caesarean section was more likely in group A (P < 0.05). Pregnancy‐induced hypertension had a higher incidence in group B than in group C (P < 0.05). Gestational age at delivery was associated with OGTT2h, premature fetal membrane rupture and self‐monitoring of blood glucose.
Conclusion
GDM treatment based on the WeChat platform effectively reduces FBG and 2‐h PBG and may improve pregnancy outcomes. However, 1‐h PBG was not affected by treatment. Obstetricians should consider the OGTT2h value to increase gestational age at delivery.
ObjectiveTo investigate the relationship between job satisfaction, work stress, work–family conflict and turnover intention, and explore factors associated with turnover intention, among physicians ...in Guangdong Province, China.MethodsFrom August to October 2013, physicians completed questionnaires and scales with regard to their job satisfaction, work stress, work–family conflict, and turnover intention. Binary logistic regression and structural equation modelling (SEM) were used in data analysis.ResultsA total of 3963 physicians were approached, with 3563 completing the questionnaire. The mean score of the overall perception of turnover intention of physicians who worked in Guangdong was 2.71 on a scale ranging from 1 to 6. Hours worked per week, working in an urban/rural area, type of institution, and age significantly impacted on turnover intention. Turnover intention was directly and negatively related to job satisfaction, and it was directly, indirectly and positively related to work stress and work–family conflict.ConclusionJob satisfaction, work stress, work–family conflict, hours worked per week, working in an urban/rural area, types of institution and age are influencing factors of turnover intention. Reducing working hours, raising salary, providing more opportunities for career development and training, supporting and encouraging physicians by senior managers could potentially contribute to the reduction in turnover intention.
A convenient and rapid detection method for methanol in ethanol remains a major challenge due to their indistinguishable physical properties. Herein, a novel fluorescence probe based on perovskite ...was successfully designed to overcome this bottleneck. We report a new zero‐dimensional (0D) hybrid perovskite of MP2InxSb1−xCl7 ⋅ 6 H2O (MP=2‐methylpiperazine) displaying an unusual green light emission with near‐unity photoluminescence quantum yield. Remarkably, this 0D perovskite exhibits reversible methanol‐response luminescence switching between green and yellow color but fail in any other organic vapors. Even for blended alcohol solutions, the luminescent probe exhibits excellent sensing performance with multiple superiorities of rapid response time (30 s) and ultra‐low detection limit (40 ppm), etc. Therefore, this 0D perovskite can be utilized as a perfect fluorescence probe to detect traces of methanol from ethanol with ultrahigh sensitivity, selectivity and repeatability. To the best of our knowledge, this work represents the first perovskite as fluorescence probe for methanol with wide potential in environmental monitoring and methanol detection, etc.
0D hybrid lead‐free halide displays highly efficient broadband green light emission with a near‐unity photoluminescence quantum yield, and acts as a unique fluorescence sensor for methanol in ethanol with ultrahigh selectivity, sensitivity and repeatability as well as fast response time.
Advances in the chemical and electrochemical transformation of carbon and water are vital for delivering affordable and environmentally friendly energy sources and chemicals. Central to this ...challenge is the performance of materials. Traditionally, noble metal particles or metal complexes have been used as catalysts for many reactions. Recently, 3d transition‐metal single‐site catalysts (3dTM‐SSCs) have emerged as potentially transformational candidates for the next‐generation high‐performance noble‐metal‐free catalysts. Designing catalysts at the molecular level can lead to a more efficient utilization of metal atoms and at the same time enhance catalytic performance under harsh reaction conditions. Despite this promise, several fundamental issues remain, in particular the structural evolution of 3dTM‐SSCs during the synthesis, the molecular‐level insights into the structure of the active sites, catalytic mechanisms, and the long‐term cycling stability. Here, the material chemistries that facilitate the 3dTM‐SSCs generation through a controlled pyrolytic synthesis are discussed, with focus on elucidating the underlying performance descriptors that can tune the catalytic properties in various critical reactions in carbon and water cycles. The current challenges and possible solutions for improving these novel catalytic materials are also highlighted.
A critical review is provided on the progress of integrating 3d transition‐metal single‐site catalysts into carbon using support‐assisted pyrolysis, with applications toward key chemical and electrochemical reactions in carbon and water cycles. The latest material chemistry developments that enable the identification of catalytic reaction centers, key performance descriptors that influence catalyst activity and stability, are highlighted.
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