74 research outputs found

    Carbazole isomers induce ultralong organic phosphorescence

    Get PDF
    Commercial carbazole has been widely used to synthesize organic functional materials that have led to recent breakthroughs in ultralong organic phosphorescence1, thermally activated delayed fluorescence2,3, organic luminescent radicals4 and organic semiconductor lasers5. However, the impact of low-concentration isomeric impurities present within commercial batches on the properties of the synthesized molecules requires further analysis. Here, we have synthesized highly pure carbazole and observed that its fluorescence is blueshifted by 54 nm with respect to commercial samples and its room-temperature ultralong phosphorescence almost disappears6. We discover that such differences are due to the presence of a carbazole isomeric impurity in commercial carbazole sources, with concentrations <0.5 mol%. Ten representative carbazole derivatives synthesized from the highly pure carbazole failed to show the ultralong phosphorescence reported in the literature1,7,8,9,10,11,12,13,14,15. However, the phosphorescence was recovered by adding 0.1 mol% isomers, which act as charge traps. Investigating the role of the isomers may therefore provide alternative insights into the mechanisms behind ultralong organic phosphorescence1,6,7,8,9,10,11,12,13,14,15,16,17,18

    Modified Technique of Pancreaticogastrostomy for Soft Pancreas with Two Continuous Hemstitch Sutures: A Single-Center Prospective Study

    Get PDF
    Postoperative pancreatic fistula (POPF) remains a persistent problem after pancreaticoduodenectomy (PD), especially in the presence of a soft, nonfibrotic pancreas. To reduce the risk of POPF, pancreaticogastrostomy (PG) is an optional reconstruction technique for surgeons after PD. This study presents a new technique of PG for a soft, nonfibrotic pancreas with double-binding continuous hemstitch sutures and evaluates its safety and reliability. From January 2011 to June 2012, 92 cases of patients with periampullary malignancy with a soft pancreas underwent this technique. A modified technique of PG was performed with two continuous hemstitch sutures placed in the mucosal and seromuscular layers of the posterior gastric wall, respectively. Then the morbidity and mortality was calculated. This technique was applied in 92 patients after PD all with soft pancreas. The median time for the anastomosis was 12 min (range, 8–24). Operative mortality was zero, and morbidity was 16.3 % (n = 15), including hemorrhage (n = 2), biliary fistula (n = 2), pulmonary infection (n = 1), delayed gastric emptying (DGE; n = 5, 5.4 %), abdominal abscess (n = 3, one caused by PF), and POPF (n = 2, 2.2 %). Two patients developed a pancreatic fistula (one type A and one type B) classified according to the International Study Group on Pancreatic Fistula. The described technique is a simple and safe reconstruction procedure after PD, especially for patients with a soft and fragile pancreas. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11605-013-2183-8) contains supplementary material, which is available to authorized users

    Aspect of Clusters Correlation at Light Nuclei Excited State

    Full text link
    The correlation of αα\alpha\alpha was probed via measuring the transverse momentum pTp_{T} and width δpT\delta p_{T} of one α\alpha, for the first time, which represents the spatial and dynamical essentialities of the initial coupling state in 8^{8}Be nucleus. The weighted interaction vertex of 3α\alpha reflected by the magnitudes of their relative momentums and relative emission angles proves the isosceles triangle configuration for 3α\alpha at the high excited energy analogous Hoyle states.Comment: 8 pages, 9 figure

    Variation of Tensor Force due to Nuclear Medium Effect

    Full text link
    The enhancement of Jπ(T)J^{\pi}(T)=3+^{+}(0) state with isospin T=0T=0 excited by the tensor force in the free 6^{6}Li nucleus has been observed, for the first time, relative to a shrinkable excitation in the 6^{6}Li cluster component inside its host nucleus. Comparatively, the excitation of Jπ(T)J^{\pi}(T)=0+^{+}(1) state with isospin T=1T=1 for these two 6^{6}Li formations take on an approximately equal excitation strength. The mechanism of such tensor force effect was proposed due to the intensive nuclear medium role on isospin TT=0 state.Comment: 6 pages, 4 figure

    Upgrading ketone synthesis direct from carboxylic acids and organohalides

    No full text
    Due to their abundance and importance in organic chemistry, development of methods for ketone synthesis is essential. Here, the authors report a photoredox, nickel and phosphoranyl radical synergistic cross-electrophile coupling of aromatic acids and aryl/alkyl bromides to directly synthesise ketones

    Identification of small molecule drugs and development of a novel autophagy‐related prognostic signature for kidney renal clear cell carcinoma

    No full text
    Abstract Abnormal autophagic levels have been implicated in the pathogenesis of multiple cancers, however, its role in tumors is complex and has not yet been explored clearly. Hence, we aimed to explore the prognostic values of autophagy‐related genes (ARGs) for kidney renal clear cell carcinoma (KIRC). Differentially expressed ARGs and transcription factors (TFs) were identified in KIRC patients obtaining from the The Cancer Genome Atlas (TCGA) database. Then, networks between TFs and ARGs, gene ontology functional annotations and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis were conducted. Next, we performed consensus clustering, COX regression analysis and Lasso regression analysis to identify the prognostic ARGs. Finally, an individual prognostic index (PI, riskScore) was established. Based on TCGA cohort and ArrayExpress cohort, Survival analysis, ROC curve, independent prognostic analysis, and clinical correlation analysis were also performed to evaluate this PI. Based on differentially expressed ARGs, KIRC patients were successfully divided into two clusters (P = 5.916e‐04). AS for PI, it was constructed based on 11 ARGs and significantly classified KIRC patients into high‐risk group and low‐risk group in terms of OS (P = 4.885e‐15 for TCGA cohort, P = 6.366e‐03 for ArrayExpress cohort). AUC of its ROC curve reached 0.747 for TCGA cohort and 0.779 for ArrayExpress cohort. What's more, this PI was proven to be a valuable independent prognostic factor in both univariate and multivariate COX regression analysis (P < .001). Prognostic nomograms were also performed to visualize the relationship between individual predictors and survival rates in patients with KIRC. By means of connectivity map database, emetine, cephaeline and co‐dergocrine mesilate related to ARGs were found to be negatively correlated with KIRC. This study provided an effective PI for KIRC and also displayed networks between TFs and ARGs. KIRC patients were successfully divided into two clusters based on differentially expressed ARGs. Besides, small molecule drugs related to ARGs were also identified for KIRC

    Copper-Catalyzed Cascade Phosphorylation Initiated Radical Cyclization: Access to 2‑Phosphorylated Pyrrolo[1,2‑<i>a</i>]indole

    No full text
    A copper-catalyzed tandem radical cyclization of 1-(3-phenylprop-2-yn-1-yl)-1<i>H</i>-indole with diphenylphosphine oxides was developed. C–P bond formation was achieved coupled with C­(sp<sup>2</sup>)–H functionalization. It provided an access to construct the pyrrolo­[1,2-<i>a</i>]­indole motif and a series of 2-phosphinoyl-9<i>H</i>-pyrrolo­[1,2-<i>a</i>]­indoles
    corecore