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Lunar exploration has drawn attention all over the world, and remote sensing of the lunar surface through the satellite’s optical camera is one of the most important ways to provide scientific data. Although on-orbit measurement is the ultimate goal, lunar exploration is a huge cost project, so researchers should take on-ground simulations and experiments to evaluate the performance of the optical instrument and provide basic references before launch. In this article, we propose an optical imaging chain modeling algorithm that focuses on the physical imaging process from light scattering among the 3-D lunar surface to the optical instrument’s output digital value (DV). Compared to other optical signal measurement simulations, we make progress in considering the 3-D structure of the observed scene, the spectral property of the imaging parameters, and corresponding absolute calibration methods. The proposed method is verified in a scaling experiment for lunar optical remote sensing with a calibrated optical camera, simulated moon soil, and a parallel light source. We compare the imaging simulation results with the experiment results for directly illuminated lunar regions, shadowed lunar regions, and multispectral imaging tasks, and the results show average relative errors (REs) around 2.4%, 11.5%, and 4.3% and coefficients of determination around 0.972, 0.942, and 0.915 for the three cases, respectively. Both the modeling algorithm and the scaling experiment will provide basic analysis for optical imaging in lunar remote sensing before the execution of a real project.

This paper describes the construction of a phase shifter with low loss and small volume. To construct it, we use the two graphene layers that are separated by a hexagonal boron nitride (hBN) and embedded in a silicon waveguide. The refractive index of the waveguide is adjusted by applying a bias voltage to the graphene sheet to create an optical phase shift. This waveguide is a compact device that only has a radius of 5 μm. It has a phase shift of 6π. In addition, the extinction ratio (ER) is 11.6 dB and the insertion loss (IL) is 0.031 dB. Due to its unique characteristics, this device has great potential in silicon on-chip optical interconnection and all-optical multiple-input multiple-output processing.

Objective This study aimed to screen and identify central genes associated with the progression of non-alcoholic fatty liver disease (NAFLD) to hepatocellular carcinoma (HCC), to establish prognostic and clinical prediction models based on the expression of these genes, and to evaluate the intervention of a traditional Chinese medicine (TCM) formula—SPXJF—on the development of NAFLD into HCC through network pharmacology analysis and in vitro and in vivo validation.Methods Datasets for analysis were retrieved from multiple public databases using bioinformatics techniques. Through network pharmacology analysis, SPXJF's active components and their related targets were assessed, while in vitro experiments validated the inhibitory effects of SPXJF on the growth and migration of HepG2 cells.Results The results revealed that the expression levels of the two central genes, regulator of cell cycle gene (RGCC) and atypical chemokine receptor 3 (ACKR3), were closely tied to the survival prognosis of HCC patients. Furthermore, SPXJF significantly inhibited the proliferation and migration of HepG2 cells.Conclusion RGCC and ACKR3, as hub genes, significantly influence HCC patient survival during “NAFLD-HCC” progression. The risk scoring system and prediction model perform well. In vitro experiments showed that SPXJF could inhibit the proliferation and invasion of hepG2 cells. These findings support the discovery of molecular targets for early diagnosis and drug intervention in HCC. They also underscore TCM's potential in anti-HCC strategies and clinical application.

This Letter demonstrates a filterless v-band signals and pulses generator scheme with a tunable optical carrier to sideband ratio (OCSR). Through complete theoretical analysis, the mathematical expression of the OCSR that contains the extinction ratio, phase modulation index, and bias angle is obtained. It is found that the OCSR has a wide tuning range, from 50 to −70??dB. By careful adjustment, a 60 GHz millimeter-wave signal with the OCSR at 50.72 dB and the electrical spurious suppression ratio at 36.6 dB can be achieved. Moreover, the discussions of using optimum OCSR to generate a Nyquist pulse or triangular-shaped pulse are also presented in this Letter.

An approach to reducing the harmonic distortion in frequency-doubled triangular-shaped pulse train generation is proposed. It requires a dual-parallel Mach-Zehnder modulator followed by a section of dispersive fiber, as the key component. The basic principle is to make the expression of optical intensity approximately equal to the Fourier expansion of idea triangular-shaped waveform. A detailed expression of the final optical intensity is given by theory and then verified by simulation. It is found that the impact of the undesired harmonic distortion is greatly reduced.