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To guarantee the security and high-efficiency of image transmission, a novel triple-image encryption scheme based on chaotic system, S-box and image compressing is proposed in this paper. Firstly, the combination process is performed by compressing three plain images to 25% and combining the compressed images with a stochastic matrix generated by the 2D-LSCM system to construct a new image. This process makes the proposed image encryption scheme have higher image transmission efficiency comparing to that of the state-of-the-art methods. Then, Z-scan and the proposed coded lock scrambling algorithm with low time complexity is used to randomly scramble the positions of pixels in the new construct image. Next, a cipher image is obtained by performing the diffusion operation on the scrambled image through S-box and chaotic sequences. In addition, the added stochastic matrix in the combination process makes the cipher image dynamic. In other words, the generated cipher images are always different to each other even when they are generated by the proposed encrypt scheme with identical plain images under the same secret keys, which can resist chosen-plaintext attacks. Finally, experimental results and simulation analysis are performed, which shows the proposed scheme can effectively resist common kinds of attacks.

With the rapid development of modern industry, it is urgently needed to measure the biotoxicity of complex chemicals. Microbial electrochemical biotoxicity sensors are an attractive technology; however, their application is usually limited by their stability and reusability after measurements. Here, we improve their performance by encapsulating the electroactive biofilm with polydopamine (PDA), and we evaluate the improvement by different concentrations of heavy metal ions (Cu2+, Ag+, and Fe3+) in terms of inhibition ratio (IR) and durability. Results indicate that the PDA-encapsulated sensor exhibits a more significant detection concentration than the control group, with a 3-fold increase for Cu2+ and a 1.5-fold increase for Ag+. Moreover, it achieves 15 more continuous toxicity tests than the control group, maintaining high electrochemical activity even after continuous toxicity impacts. Images from a confocal laser scanning microscope reveal that the PDA encapsulation protects the activity of the electroactive biofilm. The study, thus, demonstrates that PDA encapsulation is efficacious in improving the performance of microbial electrochemical biotoxicity sensors, which can extend its application to more complex media. [ABSTRACT FROM AUTHOR]

Dearomative 1,3-dipolar cycloadditions of 1-Boc-pyrroles with in situ generated silver α-bromo alkylidenenitronates delivered a series of 3a,6a-dihydro-4-Boc-pyrrolo[2,3-d]isoxazole-2-oxides (17–91% yields) under very mild conditions. N-Deoxygenation of the cycloaddition product gave a dihydro-pyrrolo[2,3-d]isoxazole, elaborations of which produced various functionalized 2,3-dihydropyrroles and pyrrolidines, showcasing the potential utilities of our new strategy of pyrrole dearomatization. [ABSTRACT FROM AUTHOR]

Background: CircRNA‐encoded proteins (CEPs) are emerging as new players in health and disease, and function as baits for the common partners of their cognate linear‐spliced RNA encoded proteins (LEPs). However, their prevalence across human tissues and biological roles remain largely unexplored. The placenta is an ideal model for identifying CEPs due to its considerable protein diversity that is required to sustain fetal development during pregnancy. The aim of this study was to evaluate circRNA translation in the human placenta, and the potential roles of the CEPs in placental development and dysfunction. Methods: Multiomics approaches, including RNA sequencing, ribosome profiling, and LC‐MS/MS analysis, were utilised to identify novel translational events of circRNAs in human placentas. Bioinformatics methods and the protein bait hypothesis were employed to evaluate the roles of these newly discovered CEPs in placentation and associated disorders. The pathogenic role of a recently identified CEP circPRKCB119aa in preeclampsia was investigated through qRT‐PCR, Western blotting, immunofluorescence imaging and phenotypic analyses. Results: We found that 528 placental circRNAs bound to ribosomes with active translational elongation, and 139 were translated to proteins. The CEPs showed considerable structural homology with their cognate LEPs, but are more stable, hydrophobic and have a lower molecular‐weight than the latter, all of which are conducive to their function as baits. On this basis, CEPs are deduced to be closely involved in placental function. Furthermore, we focused on a novel CEP circPRKCB119aa, and illuminated its pathogenic role in preeclampsia; it enhanced trophoblast autophagy by acting as a bait to inhibit phosphorylation of the cognate linear isoform PKCβ. Conclusions: We discovered a hidden circRNA‐encoded proteome in the human placenta, which offers new insights into the mechanisms underlying placental development, as well as placental disorders such as preeclampsia. Key points: A hidden circRNA‐encoded proteome in the human placenta was extensively identified and systematically characterised.The circRNA‐encoded proteins (CEPs) are potentially related to placental development and associated disorders.A novel conserved CEP circPRKCB119aa enhanced trophoblast autophagy by inhibiting phosphorylation of its cognate linear‐spliced isoform protein kinase C (PKC) β in preeclampsia. [ABSTRACT FROM AUTHOR]

Background. Altered maternal serum lipid metabolism is associated with hypertensive disorders in pregnancy (HDP). However, its range in pregnancy and characteristic among different subgroups of HDPs are unclear. Methods. Pregnant women with HDP who underwent antenatal care and delivered in Obstetrics and Gynecology Hospital of Fudan University during January 2018 to August 2022 were enrolled. The levels of total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDLC), low-density lipoprotein cholesterol (LDLC), apolipoprotein (Apo)-A, B, and E, free fatty acids (FFA), and small and dense low-density lipoprotein cholesterol (sdLDL) were measured during 4–16 weeks and 28–42 weeks of pregnancy. Results. A total of 2648 pregnant women were diagnosed with HDP, 1,880 of whom were enrolled for final analysis, including 983 (52.3%) preeclampsia (PE), 676 (36.0%) gestational hypertension (GH), and 221 (11.7%) chronic hypertension (CH). For all HDPs, serum TC, TG, LDLC, HDLC, Apo-A, Apo-B, Apo-E, and sdLDL increased significantly during pregnancy, while FFA decreased significantly. Notably, the levels of TC, LDLC, Apo-B, and sdLDL in PE group were equal to or lower than those in CH group at 4–16 weeks of pregnancy, but increased greatly during pregnancy (P < 0.05). Conclusions. Maternal serum lipid levels changed through pregnancy among women with HDPs. Women complicated with PE seem to have undergone a more significant serum lipid change compared to those with GH or CH. [ABSTRACT FROM AUTHOR]

Network energy resources are limited in communication systems, which may cause energy shortages in mobile devices at the user end. Active Reconfigurable Intelligent Surfaces (A-RIS) not only have phase modulation properties but also enhance the signal strength; thus, they are expected to solve the energy shortage problem experience at the user end in 6G communications. In this paper, a resource allocation algorithm for maximizing the sum of harvested energy is proposed for an active RIS-assisted Simultaneous Wireless Information and Power Transfer (SWIPT) system to solve the problem of low performance of harvested energy for users due to multiplicative fading. First, in the active RIS-assisted SWIPT system using a power splitting architecture to achieve information and energy co-transmission, the joint resource allocation problem is constructed with the objective function of maximizing the sum of the collected energy of all users, under the constraints of signal-to-noise ratio, active RIS and base station transmit power, and power splitting factors. Second, the considered non-convex problem can be turned into a standard convex problem by using alternating optimization, semi-definite relaxation, successive convex approximation, penalty function, etc., and then an alternating iterative algorithm for harvesting energy is proposed. The proposed algorithm splits the problem into two sub-problems and then performs iterative optimization separately, and then the whole is alternately optimized to obtain the optimal solution. Simulation results show that the proposed algorithm improves the performance by 45.2% and 103.7% compared to the passive RIS algorithm and the traditional without-RIS algorithm, respectively, at the maximum permissible transmitting power of 45 dBm at the base station. [ABSTRACT FROM AUTHOR]