Parity–time ( PT ) symmetric lattices have been widely studied in controlling the flow of waves, and recently, moiré superlattices, connecting the periodic and non-periodic potentials, have been introduced for exploring unconventional physical properties in physics, while the combination of both and nonlinear waves therein remains unclear. Here, we report a theoretical survey of nonlinear wave localizations in PT symmetric moiré optical lattices, with the aim of revealing localized gap modes of different types and their stabilization mechanism. We uncover the formation, properties, and dynamics of fundamental and higher-order gap solitons as well as vortical ones with topological charge, all residing in the finite bandgaps of the underlying linear-Bloch wave spectrum. The stability regions of localized gap modes are inspected in two numerical ways: linear-stability analysis and direct perturbance simulations. Our results provide an insightful understanding of soliton physics in combined versatile platforms of PT symmetric systems and moiré patterns.

Solitons in the fractional space, supported by lattice potentials, have recently attracted much interest. The limit of deep 1D and 2D lattices in this system is considered, featuring finite bandgaps separated by nearly flat Bloch bands. Such spectra are also a subject of great interest in current studies. The existence, shapes, and stability of various localized modes, including fundamental gap and vortex solitons, are investigated by means of numerical methods; some results are also obtained with the help of analytical approximations. In particular, the 1D and 2D gap solitons, belonging to the first and second finite bandgaps, are tightly confined around a single cell of the deep lattice. Vortex gap solitons are constructed as four-peak "squares" and "rhombuses" with imprinted winding number S = 1. Stability of the solitons is explored by means of the linearization and verified by direct simulations.

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A large number of certified samples are usually required to build models in the quantitative analysis of complicated matrices in laser-induced-breakdown spectroscopy (LIBS). Because of differences among instruments, including excitation and collection efficiencies, a quantitative model made on one instrument is difficult to apply directly to other instruments. Each instrument requires a large number of samples to model, which is very labor intensive and will hinder the rapid application of the LIBS technique. To eliminate the differences in spectral data from different instruments and reduce the cost of building new models, a piecewise direct standardization method combined with partial least squares (PLS_PDS) is studied in this work. Two portable LIBS instruments with the same configuration are used to obtain spectral data, one of which is called a master instrument because its calibration model is directly built on a large number of labeled samples, and the other of which is called a slave instrument because its model is obtained from the master instrument. The PLS_PDS method is used to build a transfer function of spectra between the master instrument and slave instrument to reduce the spectral difference between two instruments, and thus one calibration model can adapt to different instruments. Results show that for multiple elemental analyses of aluminium alloy samples, the number of samples required for slave modeling was reduced from 51 to 14 after model transferring by PLS_PDS, and the quantitative performance of the slave instrument was close to that of the master instrument. Therefore, the model transfer method can obviously reduce the sample number of building models for slave instruments, and it will be beneficial to advance the application of LIBS.

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Present report evaluates the role of alpha-4 beta-2 nicotinic receptor (α4β2 nAChRs) in the development of cardiopulmonary bypass (CPB) surgery induced brain injury. Brain injury was induced by CPB and animals were treated with α4β2 nAChRs agonist (DHβE 9 mg/kg, s.c.) and α4β2 nAChRs antagonist (MLA 10 mg/kg, i.p.) 3 hr before the induction of CPB in the separate groups. Effect of α4β2 nAChRs agonist was determined on the neurological function in CPB induced brain injured rats. Level of cytokines, ROS and expression of NLRP3, ZO-1 and Occluding proteins were estimated in CPB induced brain injured rats. Effect of α4β2 nAChRs agonist was determined on the neuronal apoptosis and histopathological changes in the brain tissue. Result of the study suggest that neurological score was reversed in α4β2 nAChRs agonist treated group than CPB group. Level of cytokines and ROS was reduced in α4β2 nAChRs agonist treated group than CPB group. Neuronal apoptosis in α4β2 nAChRs agonist treated group was found to be reduced compared to CPB group of rats. Moreover Activation of α4β2 nAChRs ameliorates the altered expression of NLRP3, ZO-1 and Occluding protein in the brain tissue of CPB induced brain injured rats. In conclusion, Data of report suggest that treatment with α4β2 nAChRs agonist protects the brain injury in cardiopulmonary bypass surgery induced brain injury by regulating NLRP3 pathway.