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Perovskite light-emitting diodes (PeLEDs) own great attention in recent years, due to their narrow emission bandwidth and tunable emission spectrum. E cient red emission is one of most important part for lighting and display. Quasi-two-dimensional (quasi-2D) perovskite could deliver high emission e ciency due to the strong carrier con nement, while the external quantum e ciencies (EQE) of red quasi-2D PeLEDs are ine cient at present, which is due to the complex distribution of different n-value phases in quasi-2D perovskite lms. Here, we nely control the phase distribution of the quasi-2D perovskite by mixing two different large organic cations, which effectively reduce the amount of smaller n index phases, meanwhile the passivation of lead and halide defects in perovskite lms is realized.Accordingly, the PeLEDs showed 25.8% EQE and 1300 cd•m-2 maximum brightness at 680 nm, which exhibit the highest performance for red PeLEDs up to now. Full TextSolution-processed metal halide perovskites have attracted considerable research interest as a new type of semiconductor materials, which has been utilized in solar cells, light-emitting diodes and other optoelectronic devices [1][2][3][4][5][6][7][8] . In particular, Perovskite light-emitting diodes (PeLEDs) have been conferred as the cutting-edging research due to their high performance [9][10][11][12][13][14][15][16] , red emission is very important in the eld of lighting and display. To date, the red PeLEDs have achieved signi cant external quantum e ciencies (EQE) that over 20%, most of them are based on the three-dimensional (3D) and quantum-dot (QD) perovskite material [17][18][19][20][21][22] .Compared with 3D and QD perovskite, quasi-two-dimensional (quasi-2D) perovskite could be more e cient emission material due to its higher exciton binding energy, multi-quantum-well structure and good charge transfer properties [23][24][25][26][27][28] . Ruddlesden-Popper perovskite (RPP) is generally described by the formula of L 2 A n-1 B n X 3n+1 as typical quasi-2D perovskites, which consist of large organic cation L, a small organic or cesium cation A, divalent metal cation B (lead or tin), and halide anion X (Cl -, Bror I -).Although the overall development of red LED is remarkable, the quasi-2D red LEDs are still in arrears of e ciency. The reason may be that ne control of quasi-2D perovskite phase (represents the thickness of the [PbI 6 ] 4octahedra layers capped by the L cations [28][29][30][31] ) distribution is a great challenge, which make the inferior charge injection and serious non-radiative recombination.In this work, we report a general strategy of cospacer cations to control the phase distribution in RPP lms, by mixing a representative of phenethylammonium iodide (PEAI)/ 3-uorophenylethylammonium iodide (m-F-PEA) and 1-naphthylmethylammonium iodide (NMAI) to alloy the RPP lms. These RPP lms show signi cant suppression of small index phase (n=2), and the carrier transport has been improved effectively. At the same time, the mixing of NMA can reduce the metall...

ObjectiveNon-alcoholic fatty liver disease (NAFLD) is the leading cause of end-stage liver diseases worldwide. Understanding NAFLD prevalence and trends over time at the global, regional and national levels is critical to understanding the NAFLD disease burden and creating more tailored prevention strategies.DesignPopulation-based observational study.SettingThe study was global, including 21 regions and 195 countries or territories.Main outcomes measureThe estimated annual percentage change for NAFLD prevalence.ResultsWorldwide, cases of NAFLD have increased from 391.2 million in 1990 to 882.1 million in 2017, with the prevalence rate increasing from 8.2% to 10.9% during the same period. The increasing trends were consistent across sexes. Case numbers were highest in East Asia, followed by South Asia, then North Africa and the Middle East. The highest prevalence of NAFLD was observed in North Africa and the Middle East, while the greatest increase was detected in Western Europe, followed by Tropical Latin America, then high-income North America.ConclusionNearly all countries or territories worldwide have experienced a significant increase in NAFLD prevalence. The greatest increase was observed in Oman. Almost all countries showed a significant increasing trend in NAFLD prevalence over the past three decades. This drastic increase is alarming and suggests that NAFLD has emerged as a new public health concern worldwide. As such, more efficient prevention strategies are urgently needed.

Antimicrobial agents have been used in meat production for decades and its consumption is considered an key driver for the emergence and dissemination of antimicrobial resistance (AMR). However, large-scale studies on AMR changes in animal isolates since the introduction of antimicrobial usage remain scarce. We applied whole genome sequencing analysis to 982 animal-derived Escherichia coli collected in China from 1970s to 2019 and found increasing trends for the presence of numerous antimicrobial resistance genes (ARGs), including those conferring resistance to critically important agents for veterinary ( orfenicol and nor oxacin) and human medicine (colistin, cephalosporins, and meropenem). Extensive diversity and increasing complexity of ARGs and their associated mobile genetic elements (MGEs) such as plasmids were also observed. The plasmids, IncC, IncHI2, IncK, IncI, IncX and IncF played a key role as highly effective vehicles for disseminating ARGs. Correlation analysis also revealed an association between antimicrobial production and emergence of ARGs at a spatial and temporal level. Prohibiting or strictly curtailing antimicrobial use in animals will potentially negate the current trends of AMR as the bacterial genome is highly changeable and using different drugs of the same class, or even unrelated classes, may co-select for MGEs carrying a plethora of co-existing ARGs. Therefore, limiting or ceasing antimicrobial use in animals to control AMR requires careful consideration.

Metal halide perovskites with 3D crystal structures have been attracting widespread attention in the past decade for their outstanding optoelectronic properties and applications. The emergence of low‐dimensional perovskites, which have been successfully demonstrated in varying electronic and optoelectronic applications, offers a number of advantages compared with 3D counterparts due to their tunable and diverse properties. Herein, at first, it is focused on the fundamental understanding about the crystal structure and the unique optical and electronic properties of low‐dimensional perovskite, which are addressed in comparison with 3D perovskites. Moreover, recent developments in application using low‐dimensional perovskite, especially in layered perovskites, are summarized, including solar cells, light‐emitting diodes, photodetectors, lasers, and white‐light emissions, where the main strategies and parameters for enhancing materials properties and the devices performance in varying application are addressed. Finally, the perspectives for the current challenges and the future opportunities of low‐dimensional perovskites are discussed to provide a roadmap to the development in the future.

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BackgroundImatinib (IM), a tyrosine kinase inhibitor (TKI), has markedly improved the survival and life quality of chronic myeloid leukemia (CML) patients. However, the lack of specific biomarkers for IM resistance remains a serious clinical challenge. Recently, growing evidence has suggested that exosome-harbored proteins were involved in tumor drug resistance and could be novel biomarkers for the diagnosis and drug sensitivity prediction of cancer. Therefore, we aimed to investigate the proteomic profile of plasma exosomes derived from CML patients to identify ideal biomarkers for IM resistance.MethodsWe extracted exosomes from pooled plasma samples of 9 imatinib-resistant CML patients and 9 imatinib-sensitive CML patients by ultracentrifugation. Then, we identified the expression levels of exosomal proteins by liquid chromatography-tandem mass spectrometry (LC-MS/MS) based label free quantification. Bioinformatics analyses were used to analyze the proteomic data. Finally, the western blot (WB) and parallel reaction monitoring (PRM) analyses were applied to validate the candidate proteins.ResultsA total of 2812 proteins were identified in plasma exosomes from imatinib-resistant and imatinib-sensitive CML patients, including 279 differentially expressed proteins (DEPs) with restricted criteria (fold change≥1.5 or ≤0.667, p<0.05). Compared with imatinib-sensitive CML patients, 151 proteins were up-regulated and 128 proteins were down-regulated. Bioinformatics analyses revealed that the main function of the upregulated proteins was regulation of protein synthesis, while the downregulated proteins were mainly involved in lipid metabolism. The top 20 hub genes were obtained using STRING and Cytoscape, most of which were components of ribosomes. Moreover, we found that RPL13 and RPL14 exhibited exceptional upregulation in imatinib-resistant CML patients, which were further confirmed by PRM and WB.ConclusionProteomic analysis of plasma exosomes provides new ideas and important information for the study of IM resistance in CML. Especially the exosomal proteins (RPL13 and RPL14), which may have great potential as biomarkers of IM resistance.