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Perovskite materials show exciting potential for light-emitting diodes (LEDs) owing to their intrinsically high photoluminescence efficiency and color purity. The research focusing on perovskite light-emitting diodes (PeLEDs) has experienced an exponential growth in the past six years. The maximum external quantum efficiency of red, green, and blue PeLEDs has surpassed 20%, 20%, and 10%, respectively. Nevertheless, the current PeLEDs are still in the laboratory stage, and the key for further development of PeLEDs is large-area fabrication. In this paper, we briefly discuss the similarities and differences between manufacturing high-quality and large-area PeLEDs and perovskite solar cells. Especially, the general technologies for fabricating large-area perovskite films are also introduced. The effect of charge transport layers and electrodes on large-area devices are discussed as well. Most importantly, we summarize the advances of large-area (active area ≥ 30 mm2) PeLEDs reported since 2017, and describe the methods for optimizing large-area PeLEDs reported in the literature. Finally, the development perspective of PeLEDs is presented for the goal of highly efficient and large-area PeLED fabrication. It is of great significance for the application of PeLEDs in future display and lighting. [ABSTRACT FROM AUTHOR]

Florfenicol is widely used to control respiratory diseases and intestinal infections in food animals. However, there are increasing reports about florfenicol resistance of various clinical pathogens. floR is a key resistance gene that mediates resistance to florfenicol and could spread among different bacteria. Here, we investigated the prevalence of floR in 430 Pseudomonas aeruginosa isolates from human clinical samples and identified three types of floR genes (designated floR , floR-T1 and floR-T2) in these isolates, with floR-T1 the most prevalent (5.3%, 23/430). FloR-T2 was a novel floR variant identified in this study, and exhibited less identity with other FloR proteins than FloRv. Moreover, floR-T1 and floR-T2 identified in P. aeruginosa strain TL1285 were functionally active and located on multi-drug resistance region of a novel incomplete Tn 4371 -like integrative and conjugative elements (ICE) in the chromosome. The expression of the two floR variants could be induced by florfenicol or chloramphenicol. These results indicated that the two floR variants played an essential role in the host's resistance to amphenicol and the spreading of these floR variants might be related with the Tn 4371 family ICE. [ABSTRACT FROM AUTHOR]

This paper presents an alternative approach to identify and classify the group of small flying objects especially drones from others, notably birds and kites (inclusive of kiteflying), in near field, by examining the pattern of their flight paths and trajectories. The trajectories of the drones and other flying objects were extracted from multiple clips of videos including various natural and synthetic database. Four trajectories characteristics are observed and extracted from the object's flight paths, i.e., heading or turning angle, curvature, pace velocity, and pace acceleration. Subsequently, principal component analyses were applied to reduce the number of these trajectory features from 4 to 2 parameters. Multi-class classification by support vector machine (SVM) with non-linear transformation kernel was used. Multiple classification models were developed by several algorithms with various transformation kernels. The hyperparameters were optimized using Bayesian optimization. The performances of the different models are compared through the prediction accuracy of the test data. [ABSTRACT FROM AUTHOR]

Prefabricated buildings (PBs) are a new type of building construction, which are less time-consuming and cause low environmental pollution and resource consumption. They play an important role in industrialized construction and clean production and have gained worldwide attention. However, the high construction costs have become a major obstacle to their popularity and application. This study investigates the factors influencing construction costs of PBs in China using a systematic literature review (SLR), fuzzy interpretive structure modeling (fuzzy ISM), and the Matrice d’Impacts croises-multiplication appliqué an classment (MICMAC) technique. First, 32 influencing factors were identified from the SLR. Second, out of which 16 critical factors were selected and mapped in a hierarchical model through semi-structured interview screening, and the MICMAC technique was used to classify the cost-influencing factors of PBs into different categories. The results revealed that all identified factors played pivotal roles in various capacities and influenced the cost of PB construction. This study may assist administrators and policymakers in better understanding the factors that influence the costs of PBs construction to manage and reduce them. [ABSTRACT FROM AUTHOR]