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This study presents the development of mixed‐ligand quasi‐2D perovskites ((2‐PEA)x(R/S‐2‐BA)2MA1Cs1Pb3Br10+x, x = 0.8, 1.6, 2.4) for circularly polarized light‐emitting diodes (CP‐LEDs). By utilizing the strong confinement effect of 2‐phenylethylammonium (2‐PEA) and the chirality of R/S‐2‐butylammonium (R/S‐2‐BA), room‐temperature circularly polarized luminescence (CPL) across the green to deep blue spectrum is achieved. The green CPL attributes to the transfer of spin‐polarized excitons while the blue CPL originates from direct excitation of luminescent phases with intrinsic chirality. Finally, green and blue CP‐LEDs under ambient are realized. Notably, standard and deep blue CP‐EL is achieved based on 0.8PEA/(R/S‐2‐BA)‐ and 1.2PEA/(R/S‐2‐BA)‐films with impressive electroluminescent asymmetry factors (0.122 and 0.175), highlighting the potential of chiral perovskites in CP‐LEDs and opening avenues for the development of room‐temperature full‐color CP‐EL display. [ABSTRACT FROM AUTHOR]

Background To investigate susceptibility to contezolid, a novel oxazolidinone, multicentre surveillance was conducted involving 2449 strains of Staphylococcus and Enterococcus collected from 65 hospitals across China. Methods The MICs of contezolid, linezolid and other clinically significant antibiotics were determined by the broth microdilution method. Consistency with the broth microdilution method for contezolid was assessed using agar dilution method, as well as disc diffusion and ETEST for linezolid, respectively. WGS was conducted on all 20 linezolid-resistant and 30 randomly non-resistant strains to analyse linezolid resistance genes (optrA , poxtA , cfr) and 23S rRNA mutation sites. Results All strains exhibited WT susceptibility to contezolid, while resistance proportions to daptomycin, vancomycin, teicoplanin, tigecycline and eravacycline ranged from 0% to 5.2% in Staphylococcus , and from 0% to 7.8% in Enterococcus. Linezolid resistance was higher in Enterococcus faecalis (4.4%) compared with Enterococcus faecium (0.2%). Contezolid showed a lower MIC50 (0.5 mg/L) than linezolid (2 mg/L) for methicillin-resistant Staphylococcus. Against Enterococcus , contezolid demonstrated a cumulative MIC percentage of 70% for VRE and 39.1% for E. faecalis (at MIC = 1 mg/L), whereas linezolid showed 0% and 1.1%, respectively. Among the 20 linezolid-resistant Enterococcus strains, all carried the optrA gene without 23S rRNA mutations. For contezolid, MICs were 4 mg/L for 19 strains and 2 mg/L for 1 strain. The ETEST, agar dilution and disc diffusion methods showed essential and categorical agreements of >90% for linezolid, with no major errors or very major errors. Conclusions Contezolid demonstrated significant in vitro antibacterial activity against methicillin-resistant Staphylococcus , VRE and linezolid-resistant E. faecalis. [ABSTRACT FROM AUTHOR]

The surface characteristics of stimuli-responsive Pickering emulsifiers can be modified by external environmental triggers, making them highly versatile in various applications. In this study, we report three novel organic–inorganic composite structure emulsifiers. These emulsifiers were designed with a core of magnetic Fe3O4 particles, surrounded by a protective silica layer, and coated on the exterior with three distinct types of modified chitosan (CS). Experimental results demonstrate that these emulsifiers can stabilize emulsion systems consisting of liquid paraffin and deionized water at a concentration of 0.5 wt%. The unique properties of the modified CS coatings allowed for the controlled demulsification of two types of emulsions by adjusting the proton concentration. Additionally, these emulsifiers exhibited magnetic-responsive demulsification under the control of an external magnetic field. The findings of this study provide valuable insights into the design and construction of multi-responsive chitosan-based magnetic Pickering emulsifiers with controllable properties. [ABSTRACT FROM AUTHOR]

The realization of controlled modulation of ultrashort pulses in the all-solid-state visible ultrafast lasers is a challenge, limited by the development of advanced optical modulation devices. Here, we reported a Ta2PdSe6 photonic device-based controlled visible ultrafast laser that exploits the polarization-dependent optical response of the Ta2PdSe6 photonic device to modulate the pulse width. Ultrashort pulse widths of 33.3 ps and 36.6 ps can be achieved under the horizontal and vertical polarization emission, respectively. This study presents polarization-dependent photonic devices for solid-state lasers, which might lead to the creation of controlled modulation in visible ultrafast lasers. [ABSTRACT FROM AUTHOR]

Background: Osteosarcoma (OS) is the most common primary malignant bone tumor in children and adolescents, with poor outcomes for patients with metastatic disease or chemotherapy resistance. Cirsiliol is a recently found flavonoid with anti-tumor effects in various tumors. However, the effects of cirsiliol in the regulation of aggressive behaviors of OS remain unknown. Methods: The effect of cirsiliol on the proliferation of OS cells was detected using a cell counting kit-8 (CCK-8) assay and 5-ethynyl-2′-deoxyuridine (EdU) staining, while cell apoptosis was detected using flow cytometry. Immunofluorescence was applied to visualize the expression level of the mitochondria, lysosomes and microtubule-associated protein light chain 3 (LC3). A computational molecular docking technique was used to predict the interaction between cirsiliol and the AKT protein. The impact of cirsiliol on resistance was investigated by comparing it between a methotrexate (MTX)-sensitive OS cell line, U2OS, and a MTX-resistant OS cell line, U2OS/MTX. Finally, in situ xenogeneic tumor models were used to validate the anti-tumor effect of cirsiliol in OS. Results: Cirsiliol inhibited cell proliferation and induced apoptosis in both U2OS and U2OS/MTX300 OS cells. In addition, treatment with cirsiliol resulted in G2 phase arrest in U2OS/MTX300 and U2OS cells. Cell fluorescence probe staining results showed impaired mitochondria and increased autophagy in OS cells after treatment with cirsiliol. Mechanistically, it was found that cirsiliol targeted AKT by reducing the phosphorylation of AKT, which further activated the transcriptional activity of forkhead Box O transcription factor 1 (FOXO1), ultimately affecting the function of OS cells. Moreover, in situ tumorigenesis experiments showed that cirsiliol inhibited the tumorigenesis and progression of OS in vivo. Conclusions: Cirsiliol inhibits OS cell growth and induces cell apoptosis by reducing AKT phosphorylation and further promotes FOXO1 expression. These phenomena indicate that cirsiliol is a promising treatment option for OS. [ABSTRACT FROM AUTHOR]

Millions of adenosine (A) to inosine (I) RNA editing events are reported and well‐studied in eukaryotes; however, many features and functions remain unclear in prokaryotes. By combining PacBio Sequel, Illumina whole‐genome sequencing, and RNA Sequencing data of two Klebsiella pneumoniae strains with different virulence, a total of 13 RNA editing events are identified. The RNA editing event of badR is focused, which shows a significant difference in editing levels in the two K. pneumoniae strains and is predicted to be a transcription factor. A hard‐coded Cys is mutated on DNA to simulate the effect of complete editing of badR. Transcriptome analysis identifies the cellular quorum sensing (QS) pathway as the most dramatic change, demonstrating the dynamic regulation of RNA editing on badR related to coordinated collective behavior. Indeed, a significant difference in autoinducer 2 activity and cell growth is detected when the cells reach the stationary phase. Additionally, the mutant strain shows significantly lower virulence than the WT strain in the Galleria mellonella infection model. Furthermore, RNA editing regulation of badR is highly conserved across K. pneumoniae strains. Overall, this work provides new insights into posttranscriptional regulation in bacteria. [ABSTRACT FROM AUTHOR]

Phosphatidylinositol 3-kinase (PI3K) plays an important role in cell proliferation, survival, migration, and metabolism, and has become an effective target for cancer treatment. Meanwhile, inhibiting both PI3K and mammalian rapamycin receptor (mTOR) can simultaneously improve the efficiency of anti-tumor therapy. Herein, a series of 36 sulfonamide methoxypyridine derivatives with three different aromatic skeletons were synthesized as novel potent PI3K/mTOR dual inhibitors based on a scaffold hopping strategy. Enzyme inhibition assay and cell anti-proliferation assay were employed to assess all derivatives. Then, the effects of the most potent inhibitor on cell cycle and apoptosis were performed. Furthermore, the phosphorylation level of AKT, an important downstream effector of PI3K, was evaluated by Western blot assay. Finally, molecular docking was used to confirm the binding mode with PI3Kα and mTOR. Among them, 22c with the quinoline core showed strong PI3Kα kinase inhibitory activity (IC50 = 0.22 nM) and mTOR kinase inhibitory activity (IC50 = 23 nM). 22c also showed a strong proliferation inhibitory activity, both in MCF-7 cells (IC50 = 130 nM) and HCT-116 cells (IC50 = 20 nM). 22c could effectively cause cell cycle arrest in G0/G1 phase and induce apoptosis of HCT-116 cells. Western blot assay showed that 22c could decrease the phosphorylation of AKT at a low concentration. The results of the modeling docking study also confirmed the binding mode of 22c with PI3Kα and mTOR. Hence, 22c is a promising PI3K/mTOR dual inhibitor, which is worthy of further research in the area. [ABSTRACT FROM AUTHOR]

Summary: Linoleic acid has been shown as a very important precursor for meat flavour and heating parameters may affect the reaction of linoleic acid with free amino acids (FAAs) or myofibrillar proteins (MPs) and the production of volatile organic compounds (VOCs). This study was aimed to identify the VOCs during heating of linoleic acid only or with FAAs and MPs for different times by gas chromatography‐ion mobility spectrometry (GC‐IMS). Reaction systems were set up to simulate meat, and the transformation pathway of VOCs was tracked by GC‐IMS. Finally, sixty‐two VOCs were identified, of which the content of aldehydes, which had the greatest impact on the aroma of meat, reached the peak (15.94%) when heated to 60 min and then decreased. Principal component analysis (PCA) showed that the effect of heating temperature on the flavour of the system was much greater than that of heating time, and heating at 90 °C for 60 min might be considered to obtain the best flavour. The results showed that FAAs played a critical role in the formation of VOCs that were derived from the oxidation and thermal degradation of linoleic acid, controlling the composition of FAAs may further optimise the flavour of processed meat products. [ABSTRACT FROM AUTHOR]

Extreme learning machines (ELMs) have gained acceptance owing to their high efficiency and outstanding generalization ability. As a key component of data preprocessing, feature selection methods can decrease the noise or irrelevant data for ELMs. However, ELMs still do not have their own practical feature selection method for their special mechanism. In this study, we proposed a feature selection method for the ELM, named FELM. The proposed algorithm achieves highly efficient dimensionality reduction due to the feature ranking strategy. The FELM can simultaneously complete the feature selection and classification processes. In addition, by incorporating a memorization–generalization kernel into the FELM, the nonlinear case of it is issued (called FKELM). The FKELM can achieve high classification accuracy and extensive generalization by applying the property of memorization of training data. According to the experimental results on different artificial and benchmark datasets, the proposed algorithms achieve significantly better classification accuracy and faster training than the other methods. [ABSTRACT FROM AUTHOR]

A DBU/AgOTf relay‐catalyzed one‐pot reaction of 2‐alkynylbenzaldehydes and α‐diazo esters for the efficient construction of 1,3‐dihydroisobenzofuran derivatives has been documented. This protocol can tolerate a wide range of substrates and its scalability is demonstrated by the gram‐scale reaction. Moreover, the obtained 1,3‐dihydroisobenzofurans can be converted to indanone derivatives by a AgOTf‐catalyzed ring recombination process. Both of the resulting products, 1,3‐dihydroisobenzofurans and indanones, are important structural units of a variety of pharmaceuticals and natural products, and their structures are clearly confirmed by single crystal X‐ray diffraction analysis. [ABSTRACT FROM AUTHOR]

The optimal intermodal nodes and routes are two of the most challenging issues for intermodal participants. We present a two-phase approach that includes the fuzzy c-means clustering method (FCM) and a multi-objective optimization model to solve intermodal location-routing issues. A weighted sum technique and a genetic algorithm (GA) are designed to address this model. The two-phase approach is beneficial in meeting different market demand preferences of intermodal participants. It also has applications in solving the sustainable intermodal location-routing problems, further solving the network optimization problem in large-scale scenarios. A typical intermodal transport network in the Bohai Rim region is used to verify the effectiveness of this approach. The results provide references for the participants in the Bohai Rim region to choose the optimal intermodal nodes and routes. The findings also offer theoretical insights for optimizing intermodal networks in other regions of China, with goals of improving sustainable transport efficiencies. [ABSTRACT FROM AUTHOR]

Nanosecond (ns)‐pulsed air plasmas are promising for environmental and biomedical applications. This paper presented a low‐cost ns‐pulsed plasma system that consists of a two‐stage Cockcroft–Walton voltage multiplier, a spark gap gas switch, and a plasma reactor. This ns power supply generated a uniform air plasma with a volume of 25 × 25 × 2 cm and a maximum ion wind of 0.8 m/s. The ion wind transported aerosols through plasma volume. Aerosols were charged and deposited on the grounded mesh electrode. The direct interactions between reactive ns plasma and deposited aerosols can promote the development of plasma applications. [ABSTRACT FROM AUTHOR]

The process of seismic multiple removal in oil seismic exploration is crucial for the imaging of underground structures with primary reflections. The inclusion of prediction and subtraction in the multiple removal method requires adaptive subtraction to remove the complex differences between the true and modeled multiples. The traditional adaptive subtraction method is generally expressed as a linear regression (LR) problem. In this article, we introduce U-net, a popular deep learning tool, to represent the complex differences between the true and modeled multiples in a nonlinear relationship. Thus, we present adaptive subtraction as a non-LR problem. The modeled multiples and full recorded seismic response with multiples and primaries are used as the input and labels to train U-net. The proposed U-net method is able to avoid over-fitting of the primaries due to the sufficient number of 2-D data windows for the training of U-net, as well as the network parameter regularization and the L1 norm minimization constraint on the primaries. The proposed U-net method attains 20.5 dB and 2.5 dB improvement in the signal-to-noise ratio (SNR) using the first synthetic data and second synthetic (Sigsbee2B) data set, respectively, compared with the traditional LR method, and a qualitative improvement for a real data set test. [ABSTRACT FROM AUTHOR]

The first mercury-catalyzed synthesis of 1,2-diketones by alkyne oxidation has been developed. This inexpensive method extends the potential of mercury catalysis and allows the rapid construction of various 1,2-diketones and α-carbonyl amides in good yields with high functional group tolerance. [ABSTRACT FROM AUTHOR]

The COVID-19, viral influenza, tuberculosis, and other widespread infectious diseases evidence that pathogenic biological aerosols (PBAs) are a serious threat to public health. Different from traditional inactivation methods, such as ultraviolet (UV) light which are only safe to use when people are not present, and high-efficiency particulate filters (HEPA) which merely filter microbes without killing them, atmospheric pressure nonequilibrium plasma (APNP) has shown its tremendous potential in drastically diminishing the aerosol transmission route of the infectious agents through the abatement of PBAs. The key issues to develop high performance APNP based air purification system are critically reviewed. Systematic studies on the hazards of different PBAs and the spread of PBAs in indoor environments guide the development of APNP sources to control communicable diseases. The key six sampling and seven detection methods on PBAs are introduced to analyze the PBA abatement efficiency by APNP. Seven common APNP sources which can remove viruses and bacteria aerosols efficiently developed during the past 8 years are introduced. For the APNP sources with small plasma volume, the electric field and diffusion driven charging are the dominant mechanisms to charge PBAs, while the common methods of dusty plasma research can be adapted to atmospheric-pressure conditions to describe the charging effects of APNP sources with large plasma volume. Plentiful long- and short-lifetime reactive oxygen and nitrogen species (RONS) generated by APNP effectively contribute to inactivation of bacterial aerosols. Current studies suggest that viral aerosols are mainly inactivated by short-lifetime RONS including 1O2, ONOO− and ONOOH. The study on the dissolution and reaction of gaseous RONS in microdroplets and accurate measurements on the evolution of charged PBAs are envisaged to be the focus of future research. Opportunities for multidisciplinary collaborative research to advance the development of next-generation high-performance plasma-based air purifiers are highlighted. [ABSTRACT FROM AUTHOR]

Rain enhancement is the main activity field of weather modification in the countries that suffer from water stress. The charged aerosol is a new man-made condensation nucleus to enhance the water vapor condensation. In this article, the negative-polarity air plasma jet array with plasma volume larger than 2 cm3 was used to generate the charged aerosols. Aerosols are mainly charged in the unipolar atmosphere. The averaged charge number of charged aerosols was measured to be 5818e. The attractive electric force of charged aerosols was more than ten times higher than the sum of thermophoretic forces and diffusophoretic forces. These charged aerosols accelerated the collision–coalescence process inside the cloud chamber, generated large droplets in the range of 40–70 μm, and increased the settling amount of moisture by 58.8% [ABSTRACT FROM AUTHOR]

Building structures may encounter strong wind, earthquake, snowstorm, and other disaster loads during their service period. Therefore, the members and joints may incur different degrees of damages. However, some damaged members and joints can continue functioning after reasonable assessment and repair. In this study, drum-welded hollow spherical joints (DWHSJs) that are used in Beijing's New International Airport were considered as research objects. Experimental and numerical analyses were conducted to investigate the compressive bearing capacity of the DWHSJs and their degradation when they suffered damage. Then, using parametric analysis, the effect of various factors on the degradation of the bearing capacity of damaged joints was revealed. Finally, according to the experimental and numerical analysis results, a practical formula for calculating the bearing capacity of damaged joints under axial compression was proposed. A reduction factor of the bearing capacity based on the residual deformation of joints was introduced in the formula. A comparison showed that the calculation results were relatively consistent with the experimental results. [ABSTRACT FROM AUTHOR]

Adaptive multiple subtraction is an important step for the success of multiple removal after multiple prediction. Generally, the traditional method uses a 2D matching filter to combine the predicted multiples to match with the original data directly. Due to the complicated mismatches between the predicted multiples and true multiples, multiples may be removed aggressively with damaging primaries and vice versa for the traditional method. Especially in complex media, how to balance multiple removal and primary preservation is very important. In this paper we propose to use multi feature-gathers of the predicted multiples for adaptive multiple subtraction. The feature of the predicted multiples is extracted by the convolutional neural network with the predicted multiples as the input and the original data as the output. The multi feature-gathers of the predicted multiples contain more prediction information than the predicted multiples themselves. Therefore, the multi feature-gathers combined by a 3D matching filter can better match with the true multiples than the predicted multiples themselves combined by a 2D matching filter. Synthetic and field data examples demonstrate that the proposed method can better balance multiple removal and primary preservation than the traditional method. [ABSTRACT FROM AUTHOR]

This paper describes a methodology to predict the loads generated by a flexible flapping wing. The three-dimensional, whole field wing deformation was first measured using a non-contact optical technique. The measured deformation and motion were then input to a reduced-order model of the flapping wing to calculate the loads generated. Experiments were performed on a thin rectangular plate of 100 mm wing length flapping in air at a frequency of 15 Hz and stroke amplitude of 40°. The wing deformation as well as wing root loads were measured and showed good agreement with previously published data. A direct numerical simulation of the Navier–Stokes equation with exactly the same configuration, but at lower Reynolds number, provided full-field dataset for the development of data-driven reduced-order models. A modified proper orthogonal decomposition-Galerkin method, which includes extra terms to represent moving boundaries, was applied for reduced-order model development. It was found that the reduced-order model with only eight proper orthogonal decomposition modes was sufficient to show good correlation of loads with direct numerical simulations and experimentally measured trends. [ABSTRACT FROM AUTHOR]