荧光RNA及其生物传感技术研究进展

荧光RNA技术是一种新兴的RNA标记技术,可用于活细胞RNA的原位实时标记与成像,对于人们理解RNA的功能和调控机制发挥着至关重要的作用。基于荧光RNA的生物传感技术可用于活细胞内小分子代谢物以及蛋白质等靶标的实时动态检测,为生命科学基础研究以及生物医学传感技术开发提供极具价值的工具。本文对遗传编码的荧光RNA的发展历程、荧光RNA技术在活细胞RNA成像,以及基于荧光RNA的生物传感技术在活细胞代谢物检测等方面的应用进行了介绍和总结,并对该领域的发展现状和未来发展方向展开讨论和展望,以期为该技术的进一步发展和在相关领域的应用提供参考。

A surrogate model for uncertainty quantification and global sensitivity analysis of nonlinear large-scale dome structures

Full-scale dome structures intrinsically have numerous sources of irreducible aleatoric uncertainties.A large-scale numerical simulation of the dome structure is required to quantify the effects of these sources on the dynamic performance of the structure using the finite element method(FEM).To reduce the heavy computational burden,a surrogate model of a dome structure was constructed to solve this problem.The dynamic global sensitivity of elastic and elastoplastic structures was analyzed in the uncertainty quantification framework using fully quantitative variance-and distribution-based methods through the surrogate model.The model considered the predominant sources of uncertainty that have a significant influence on the performance of the dome structure.The effects of the variables on the structural performance indicators were quantified using the sensitivity index values of the different performance states.Finally,the effects of the sample size and correlation function on the accuracy of the surrogate model as well as the effects of the surrogate accuracy and failure probability on the sensitivity index values are discussed.The results show that surrogate modeling has high computational efficiency and acceptable accuracy in the uncertainty quantification of large-scale structures subjected to earthquakes in comparison to the conventional FEM.

Randomized whispering-gallery-mode microdisk laser arrays via cavity deformations for anti-counterfeiting labels

Optical physical unclonable functions(PUFs)have emerged as a promising strategy for effective and unbreakable anti-counterfeiting.However,the unpredictable spatial distribution and broadband spectra of most optical PUFs complicate efficient and accurate verification in practical anti-counterfeiting applications.Here,we propose an optical PUF-based anti-counterfeiting label from perovskite microlaser arrays,where randomness is introduced through vapor-induced microcavity deformation.The initial perovskite microdisk laser arrays with regular positions and uniform sizes are fabricated by femtosecond laser direct ablation.By introducing vapor fumigation to induce random deformations in each microlaser cavity,a laser array with completely uneven excitation thresholds and narrow-linewidth lasing signals is obtained.As a proof of concept,we demonstrated that the post-treated laser array can provide fixed-point and random lasing signals to facilitate information encoding.Furthermore,different emission states of the lasing signal can be achieved by altering the pump energy density to reflect higher capacity information.A threefold PUF(excited under three pump power densities)with a resolution of 5×5 pixels exhibits a high encoding capacity(1.43×10^(45)),making it a promising candidate to achieve efficient authentication and high security with anti-counterfeiting labels.

Nanowrinkled Carbon Aerogels Embedded with FeN_(x) Sites as Effective Oxygen Electrodes for Rechargeable Zinc-Air Battery

Rational design of single-metal atom sites in carbon substrates by a flexible strategy is highly desired for the preparation of high-performance catalysts for metal-air batteries.In this study,biomass hydrogel reactors are utilized as structural templates to prepare carbon aerogels embedded with single iron atoms by controlled pyrolysis.The tortuous and interlaced hydrogel chains lead to the formation of abundant nanowrinkles in the porous carbon aerogels,and single iron atoms are dispersed and stabilized within the defective carbon skeletons.X-ray absorption spectroscopy measurements indicate that the iron centers are mostly involved in the coordination structure of FeN_(4),with a minor fraction(ca.1/5)in the form of FeN_(3)C.First-principles calculations show that the FeN_(x) sites in the Stone-Wales configurations induced by the nanowrinkles of the hierarchically porous carbon aerogels show a much lower free energy than the normal counterparts.The resulting iron and nitrogen-codoped carbon aerogels exhibit excellent and reversible oxygen electrocatalytic activity,and can be used as bifunctional cathode catalysts in rechargeable Zn-air batteries,with a performance even better than that based on commercial Pt/C and RuO_(2) catalysts.Results from this study highlight the significance of structural distortions of the metal sites in carbon matrices in the design and engineering of highly active single-atom catalysts.