医院安全氛围在护士感知工作环境及满意度间的中介效应分析

目的探讨护士感知工作环境、医院安全氛围和护士满意度之间的关系和影响路径。方法采用便利抽样法,于2021年9月至11月选取成都市2家三级甲等综合医院和1家三级甲等专科医院护士为研究对象,以护士感知工作环境问卷、医院安全氛围量表和工作满意度量表对护士进行调查,采用Pearson相关性分析医院安全氛围、护士感知工作环境与满意度之间相关性,根据相关性检验结果建立路径关系模型,用Bootstrap法进行中介效应检验,深入剖析医院安全氛围在护士感知工作环境和满意度之间的中介效应。结果护士工作环境感知与满意度呈正相关(r=0.428,P<0.01),医院安全氛围与护士工作环境呈正相关(r=0.693,P<0.01),医院安全氛围与护士满意度呈正相关(r=0.466,P<0.01),护士感知工作环境正向预测医院安全氛围(β=0.773,P=0.003),对满意度的正向预测作用差异无统计学意义(β=0.060,P=0.530),医院安全氛围在护士感知工作环境和满意度间的间接效应值为0.414(95%CI 0.557~1.531),占总效应的87.34%。结论医院安全氛围在护士感知工作环境和满意度间起到完全中介作用,促进护理队伍健康稳定发展。

Generation of multi-wavelength square pulses in the dissipative soliton resonance regime by a Yb-doped fiber laser

Multi-wavelength square pulses are generated in the dissipative soliton resonance(DSR) regime by a Yb-doped fiber laser(YDFL) with a long cavity configuration. The spectral filter effect provided by a passive fiber with low-stress birefringence facilitates the establishment of multi-wavelength operation. Through appropriate control of the cavity parameters,a multi-wavelength DSR pulse can be generated in single-and dual-waveband regions. When the multi-wavelength DSR works in the 1038 nm waveband, the pulse duration can broaden from 2 ns to 37.7 ns. The maximum intra-cavity pulse energy is 152.7 nJ. When the DSR works in the 1038 nm and 1080 nm wavebands, the pulse duration can be tuned from2.3 ns to 10.5 ns with rising pump power. The emergence of the 1080 nm waveband is attributed to the stimulated Raman scattering(SRS) effect. Our work might help a deeper insight to be gained into DSR pulses in all-normal-dispersion YDFLs.

Copper-catalyzed C(sp)-H aryl amination enables modular synthesis of quinolines and 2-quinolinones

Herein,we disclose a novel copper-catalyzed C(sp)-H aryl amination of terminal alkynes with anthranils,enabling the rapid generation of highly reactive secondary N-aryl ynamines for the modular synthesis of structurally diverse C2-substituted quinolines and 2-quinolinones.The in-situ formed carbonyl-ynamines are prone to tautomerize to carbonyl-ketenimines,which can efficiently react with a series of nucleophiles,including amines,alcohols,phenols,thiols,thiophenols,active-methylene compounds,and even water to produce various quinoline derivatives with the generation of H_(2)O as a sole and green byproduct.This method also unlocks a practical route to create various quinoline-fused heterocycles and can be successfully applied to the late-stage modification of complex molecules and the concise synthesis of bioactive targets.Mechanistic studies reveal a coppercatalyzed inner-sphere nitrene transfer process by using anthranils as novel aryl nitrene precursors.

Intensifying uneven charge distribution via geometric distortion engineering in atomically dispersed M-N_(x)/S sites for efficient oxygen electroreduction

Fine regulation of geometric structures has great promise to acquire specific electronic structures and improve the catalytic performance of single-atom catalysts,yet it remains a challenge.Herein,a novel seed encapsulation–decomposition strategy is proposed for the geometric distortion engineering and thermal atomization of a series of Cu-N_(x)/S moieties anchored on carbon supports.During pyrolysis,seeds(Cu^(2+),CuO,or Cu_(7)S_(4) nanoparticles)confined in metal organic framework can accommodate single Cu atoms with Cu–N or Cu–S coordination bonds and simultaneously induce C–S or C–N bond cleavage in the second coordination shell of Cu centers,which are identified to manipulate the distortion degree of Cu-N_(x)/S moieties.The severely distorted Cu-N3S molecular structure endows the resultant catalyst with excellent oxygen reduction reaction activity(E_(1/2)=0.885 V)and zinc-air battery performance(peak power density of 210 mW·cm^(−2)),outperforming the asymmetrical and symmetrical Cu-N4 structures.A combined experimental and theoretical study reveals that the geometric distortion of Cu-N_(x)/S moieties creates uneven charge distribution by a unique topological correlation effect,which increases the metal charge and shifts the d-band center toward the Fermi level,thereby optimizing the inter-mediate adsorption energy.

The 4^(th) Cancer Chemoprevention Symposium,Beijing 2016——Cancer Chemoprevention by Dietary Phytochemicals and Traditional Chinese Medicines

2016年7月30～31日，由北京大学药学院主办，深圳福山生物科技有限公司独家赞助的“癌症化学预防论坛-北京2016”顺利召开，来自国内外多家知名研究机构的专家、学者参加了会议，共同探讨化学预防研究的最新进展和发展趋势。

A novel aza-naphthoquinone inhibits tumor growth by inducing apoptosis

Natural product menaquinone has been reported to exhibit antitumor activity mediated by inhibiting IDO-1 enzyme, and naphthoquinone compounds like pyranaphthoquinone have attracted extensive research interests since they share the naphthoquinone pharmacophores. In the present study, a novel series of aza-naphthoquinones was synthesized based on 6,7-dichloroquinoline-5,8-dione structure, and their cytotoxicities were screened using lung cancer cells. Among them CY-26-11 was identified as the most potent one. CY-26-11 concentration-dependently induced apoptosis in A549 human lung adenocarcinoma cells, as indicated by annexin-V staining. Further experimental data show that CY-26-11 down-regulated Bcl-2 while up-regulated Bax and Puma protein levels, and activated caspase-3. Finally, CY-26-11 significantly inhibited the growth of Lewis lung carcinoma xenografts in vivo without significant major toxicities. Taken together, our results demonstrate that CY-26-11 exhibited IDO-l-independent anti-tumor effects both in vitro and in vivo, providing a new anti-tumor mechanism for naphthoquinone compounds.

A small molecule LS-1-2F promotes the endocytosis of macromolecules into tumor cells

In the previous research, we found that anticancer agent LS-1-2 F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2 F on the endocytosis of macromolecules, including fluorescence quantum dots, human serum albumin, single-stranded RNA, and monoclonal antibody, into tumor cells. We found that LS-1-2 F could accelerate the endocytosis of these large molecules by laser confocal microscope and flow cytometry. The effect of LS-1-2 F on the improvement of the internalization efficiency of Herceptin biosimilar was particularly significant. Promoting endocytosis will help increase the efficiency of liquid-phase drug uptake in drug-resistant cancer cells and could potentially facilitate the use of drugs in nanoparticle delivery vehicles.