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It has been suggested that a cellularly unstable laminar flame, which is freely propagating in unbounded space, can accelerate and evolve into a turbulent flame with the neighbouring flow exhibiting the basic characteristics of turbulence. Famously known as self-turbulization, this conceptual transition in the flow regime, which arises from local interactions between the propagating wrinkled flamefront and the flow, is critical in extreme events such as the deflagration-to-detonation transition (DDT) leading to supernova explosions. Recognizing that such a transition in the flow regime has not been conclusively demonstrated through experiments, in this work, we present experimental measurements of flow characteristics of flame-generated 'turbulence' for expanding cellular laminar flames. The energy spectra of such 'turbulence' at different stages of cellular instability are analysed. A subsequent scaling analysis points out that the observed energy spectra are driven by the fractal topology of the cellularly unstable flamefront.

High-quality single crystals (SCs) are crucial for advanced photoelectronic devices like light-emitting diodes (LEDs), lasers, and photodetectors. Zero-dimensional organic antimony-based metal halides, such as Gua3SbX6, offer great promise due to their unique structure and high photoluminescence quantum yield (PLQY). However, producing large-sized SCs remains challenging, because the multi-site nucleation leads to parasitic crystal formation, which consumes the abundant precursors. In this study, we utilized zinc acetate as an additive to cultivate centimeter-scale Gua3SbBr6 SCs. Zn2+ ions robustly coordinate with Br− ions, effectively retarding their participation in the SC seed formation and suppressing multi-site nucleation. These optimized SCs were used to fabricate a white light-emitting diode (WLED) with a high color rendering index (CRI) of 89 and a maximum power efficiency of 48.6 lm/W, significantly outperforming conventional WLEDs. This study not only deepens our understanding of crystal growth dynamics but also addresses a key challenge, paving the way for high-performance, eco-friendly photoelectronic devices using Gua3SbBr6 SCs. [ABSTRACT FROM AUTHOR]

The H5N6 avian influenza virus (AIV) is constantly undergoing recombination and evolution with other subtypes of AIV, resulting in various types of recombinant H5N6 viruses. However, the risk to human public health of different recombinant types of H5N6 viruses remains unclear. Recently, two types of different recombinant H5N6 viruses were isolated from chickens. One of the viruses possessed six internal genes originating from H9N2, named A/Chicken/Hubei/112/2020 (H5N6) (abbreviated 112); the other virus possessed PB2, PB1, PA, and NP originating from H5N1, while the M and NS genes were derived from H9N2, named A/Chicken/Hubei/125/2020 (H5N6) (abbreviated 125). Here, we investigated the receptor binding properties, pathogenicity, and transmissibility of the two H5N6 AIVs. The results showed that 112 and 125 could bind α‐2,3‐linked sialic acid receptor (avian‐like receptor) and α‐2,6‐linked sialic acid receptor (human‐like receptor). However, 125 and 112 showed different pathogenicity in mice. Mice infected with 125 lost only a slight body weight and all survived, while mice infected with 112 lost weight rapidly and all died within a week of infection. Furthermore, in the transmission experiment, 125 could only transmit through direct contact, while 112 could transmit not only by direct contact but also by aerosol. The above results indicated that 112 exhibited enhanced pathogenicity and transmissibility compared to 125, suggesting that the H5N6 virus, whose internal genes were derived from H9N2, could pose a greater threat to human health. Therefore, continuous monitoring of different recombinant H5N6 viruses in poultry should be carried out to prevent their transmission to humans. [ABSTRACT FROM AUTHOR]

Contemporary cargo vessel transport constitutes a vital part of the global trade and economy. Thus, it is of primary engineering and design importance to further develop more efficient novel risk analysis and risk assessment methods for large cargo ships. Classical risk assessment and risk analysis methodsmay not always have advantages of efficiently dealing with dynamic system's high dimensionality along with cross-correlations between various critical dimensions. Current study benchmarks state-of-art Gaidai spatiotemporal structural risk assessment method, suitable for multivariate structural dynamic systems versus a well-established bivariate risk assessment method. As an example, for this risk assessment study, an operating container vessel has been selected. The vessel hull had been subjected to large deck panel stresses and accelerations during cross-Atlantic sailing. Risks of losing cargo containers are caused by extreme dynamics being one of the primary concerns for vessel cargo transport. Gaidai multivariate risk assessment methodology, advocated here, opens up new possibilities of predicting efficiently, yet simply potential structural damage/failure risks for nonstationary, nonlinear, multivariate cargo ship dynamic systems, as a whole. Note that advocated novel multivariate risk assessment method may be applied to a wide range of complex marine and offshore engineering systems. [ABSTRACT FROM AUTHOR]

Exosomes contain cell- and cell-state-specific cargos of proteins, lipids, and nucleic acids and play significant roles in cell signaling and cell-cell communication. Current research into exosome-based biomarkers has relied largely on analyzing candidate biomarkers, i.e., specific proteins or nucleic acids. However, this approach may miss important biomarkers that are yet to be identified. Alternative approaches are to analyze the entire exosome system, either by "omics" methods or by techniques that provide "fingerprints" of the system without identifying each individual biomolecule component. Here, we describe a platform of the latter type, which is based on surface-enhanced Raman spectroscopy (SERS) in combination with multivariate analysis, and demonstrate the utility of this platform for analyzing exosomes derived from different biological sources. First, we examined whether this analysis could use exosomes isolated from fetal bovine serum using a simple, commercially available isolation kit or necessitates the higher purity achieved by the "gold standard" ultracentrifugation/filtration procedure. Our data demonstrate that the latter method is required for this type of analysis. Having established this requirement, we rigorously analyzed the Raman spectral signature of individual exosomes using a unique, hybrid SERS substrate made of a graphene-covered Au surface containing a quasi-periodic array of pyramids. To examine the source of the Raman signal, we used Raman mapping of low and high spatial resolution combined with morphological identification of exosomes by scanning electron microscopy. Both approaches suggested that the spectra were collected from single exosomes. Finally, we demonstrate for the first time that our platform can distinguish among exosomes from different biological sources based on their Raman signature, a promising approach for developing exosome-based fingerprinting. Our study serves as a solid technological foundation for future exploration of the roles of exosomes in various biological processes and their use as biomarkers for disease diagnosis and treatment monitoring.