The effects of incident light wavelength difference on the collective stimulated Brillouin scattering in plasmas

The first laser–plasma interaction experiment using lasers of eight beams grouped into one octad has been conducted on the Shenguang Octopus facility.Although each beam intensity is below its individual threshold for stimulated Brillouin backscattering(SBS),collective behaviors are excited to enhance the octad SBS.In particular,when two-color/cone lasers with wavelength separation 0.3 nm are used,the backward SBS reflectivities show novel behavior in which beams of longer wavelength achieve higher SBS gain.This property of SBS can be attributed to the rotation of the wave vectors of common ion acoustic waves due to the competition of detunings between geometrical angle and wavelength separation.This mechanism is confirmed using massively parallel supercomputer simulations with the three-dimensional laser–plasma interaction code LAP3D.

All-optical object identification and threedimensional reconstruction based on optical computing metasurface

Object identification and three-dimensional reconstruction techniques are always attractive research interests in machine vision,virtual reality,augmented reality,and biomedical engineering.Optical computing metasurface,as a two-dimensional artificial design component,has displayed the supernormal character of controlling phase,amplitude,polarization,and frequency distributions of the light beam,capable of performing mathematical operations on the input light field.Here,we propose and demonstrate an all-optical object identification technique based on optical computing metasurface,and apply it to 3D reconstruction.Unlike traditional mechanisms,this scheme reduces memory consumption in the processing of the contour surface extraction.The identification and reconstruction of experimental results from high-contrast and low-contrast objects agree well with the real objects.The exploration of the all-optical object identification and 3D reconstruction techniques provides potential applications of high efficiencies,low consumption,and compact systems.

A nomogram-based immune-serum scoring system predicts overall survival in patients with lung adenocarcinoma

Objective:The immunoscore,which is used to quantify immune infiltrates,has greater relative prognostic value than tumor,node,and metastasis(TNM)stage and might serve as a new system for classification of colorectal cancer.However,a comparable immunoscore for predicting lung adenocarcinoma(LUAD)prognosis is currently lacking.Methods:We analyzed the expression of 18 immune features by immunohistochemistry in 171 specimens.The relationship of immune marker expression and clinicopathologic factors to the overall survival(OS)was analyzed with the Kaplan-Meier method.A nomogram was developed by using the optimal features selected by least absolute shrinkage and selection operator(LASSO)regression in the training cohort(n=111)and evaluated in the validation cohort(n=60).Results:The indicators integrated in the nomogram were TNM stage,neuron-specific enolase,carcino-embryonic antigen,CD8 center of tumor(CT),CD8 invasive margin(IM),Fox P3 CT,and CD45 ROCT.The calibration curve showed prominent agreement between the observed 2-and 5-year OS and that predicted by the nomogram.To simplify the nomogram,we developed a new immune-serum scoring system(I-SSS)based on the points awarded for each factor in the nomogram.Our I-SSS was able to stratify same-stage patients into different risk subgroups.The combination of I-SSS and TNM stage had better prognostic value than the TNM stage alone.Conclusions:Our new I-SSS can accurately and individually predict LUAD prognosis and may be used to supplement prognostication based on the TNM stage.

Kinetic study of transverse electron-scale interface instability in relativistic shear flows

Interfacial magnetic field structures induced by transverse electron-scale shear instability(mushroom instability)are found to be strongly associated with electron and ion dynamics,which in turn will influence the development of the instability itself.We find that high-frequency electron oscillations are excited normal to the shear interface.Also,on a larger time scale,the bulk of the ions are gradually separated under the influence of local magnetic fields,eventually reaching an equilibrium related to the initial shear conditions.Wepresent a theoretical model of this behavior.Such separation on the scale of the electron skin depth will prevent different ions from mixing and will thereafter restrain the growth of higher-order instabilities.We also analyze the role of electron thermal motion in the generation of the magnetic field,and we find an increase in the instability growth rate with increasing plasma temperature.These results have potential for providing a more realistic description of relativistic plasma flows.

Photonic spin Hall effect on the surface of anisotropic two-dimensional atomic crystals

We examine the spin-orbit interaction of light and photonic spin Hall effect on the surface of anisotropic two-dimensional atomic crystals. As an example, the photonic spin Hall effect on the surface of black phosphorus is investigated. The photonic spin Hall effect manifests itself as the spin-dependent beam shifts in both transverse and in-plane directions. We demonstrate that the spin-dependent shifts are sensitive to the orientation of the optical axis, doping concentration, and interband transitions. These results can be extensively extended to other anisotropic two-dimensional atomic crystals. By incorporating the quantum weak measurement techniques, the photonic spin Hall effect holds great promise for detecting the parameters of anisotropic two-dimensional atomic crystals.