As a new detection technology, polarization imaging is of great significance in the field of target detection. At present, polarization imaging technology usually adopts visible light polarization imaging. The technique is difficult to image the target in complex background due to its narrow working spectrum and short detection distance. Therefore, based on the principle of full Stokes micro-polarizer array, this paper proposes a multi-spectral polarization imaging scheme and designs a multi-spectral polarization imaging detection system penetrating haze. Conducting indoor and outdoor polarized imaging experiments. Finally, image quality was assessed using metrics such as information entropy (EN), average gradient (AG), and standard deviation (STD). The results show that compared with traditional strength detection, the imaging system has significantly improved detection distance and imaging quality in smoky environments. The imaging system can effectively enhance the contours and details of the target object and improve detection and recognition capabilities.
Diagnostic Imaging , Light , Refraction, Ocular
Since there are usually multiple layers present in a real-world sea fog environment, and because previous studies have tended to analyze sea fog as a single layer rather than as refined layered sea fog, this paper splits sea fog into two categories: water fog and salt fog double-layer environments. By adjusting the optical thickness of the two layers of media, we may investigate the issue of the law governing the transmission of polarized light. In this paper, the analysis is mainly carried out through a simulation and experimental tests. The simulation portion is based mostly on the improved layered Monte Carlo approach, which builds a simulation model more appropriate for multilayer non-spherical media by using the accumulation principle to determine the scattering and transmission properties between layers. The tests are conducted by altering the double-layer medium's optical thickness, incoming wavelength, and polarization state, and then getting the polarization information of visible light after transmission through the complicated environment. The findings demonstrate that the optical thickness of the sea fog double-layer media affects polarized light transmission in a non-negligible way. Longer wavelength polarized light may keep polarization information better as the optical thickness increases, and circularly polarized light has polarization-preserving properties that are superior to linearly polarized light. By contrasting the simulation findings with the experimental data, the consistency of the two conclusions is confirmed, and the study offers a helpful resource for the transmission of polarized light in the sea fog environment.
True natural environments are more complex, and light travels through non-spherical particle media, which can affect the transmission of light. The medium environment of non-spherical particles is more common than that of spherical particles, and some studies have shown that there are differences between spherical and non-spherical particles in polarized light transmission. Therefore, the use of spherical particles instead of non-spherical particles will result in great error. In view of this feature, this paper samples the scattering angle based on the Monte Carlo method, and then constructs a simulation model of a random sampling fitting phase function suitable for ellipsoidal particles. In this study, yeast spheroids and Ganoderma lucidum spores were prepared. The effects of different polarization states and optical thicknesses on the transmission of polarized light at three wavelengths were investigated using ellipsoidal particles with a ratio of 1.5 transverse to vertical axes. The results show that when the concentration of the medium environment increases, the polarized lights of different states all show obvious depolarization, but circularly polarized light has better polarization-preserving characteristics than linearly polarized light, and polarized light with larger wavelengths also shows more stable optical properties. When yeast and Ganoderma lucidum spores were used as the transport medium, the degree of polarization of polarized light had the same trend. However, the equal volume radius of yeast particles is smaller than that of Ganoderma lucidum spores, so when the laser is in the yeast particle medium, the polarization-maintaining property of polarized light is superior. This study provides an effective reference for the variation of polarized light transmission in an atmospheric transmission environment with heavy smoke.
BACKGROUND: Cell division cycle 25A (CDC25A) is a well-recognized regulator of cell cycle progression and is involved in cancer development. This work focused on the function of CDC25A in cervical cancer cell growth and the molecules involved. METHODS: A GEO dataset GSE63514 comprising data of cervical squamous cell carcinoma (CSCC) tissues was used to screen the aberrantly expressed genes in cervical cancer. The CDC25A expression in cancer and normal tissues was predicted in the GEPIA database and that in CSCC and normal cells was determined by RT-qPCR and western blot assays. Downregulation of CDC25A was introduced in CSCC cells to explore its function in cell growth and the cell cycle progression. The potential regulators of CDC25A activity and the possible involved signaling were explored. RESULTS: CDC25A was predicted to be overexpressed in CSCC, and high expression of CDC25A was observed in CSCC cells. Downregulation of CDC25A in ME180 and C33A cells reduced cell proliferation and blocked cell cycle progression, and it increased cell apoptosis. ALX3 was a positive regulator of CDC25A through transcription promotion. It recruited a histone demethylase, lysine demethylase 2B (KDM2B), to the CDC25A promoter, which enhanced CDC25A expression through demethylation of H3k4me3. Overexpression of ALX3 in cells blocked the inhibitory effects of CDC25A silencing. CDC25A was found as a positive regulator of the PI3K/Akt signaling pathway. CONCLUSION: This study suggested that the ALX3 increased CDC25A expression through KDM2B-mediated demethylation of H3K4me3, which induced proliferation and cell cycle progression of cervical cancer cells.
Histone Demethylases/metabolism , Homeodomain Proteins/metabolism , Uterine Cervical Neoplasms/metabolism , Animals , Cell Proliferation/physiology , Female , Humans , Mice , Mice, Nude , Transfection , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology
A pupil modulator is a useful tool to improve the resolution of an optical imaging system beyond the classical diffraction limit. However, when this technology is used in a large-aperture telescopic imaging system, the field of view (FOV) with good superresolution (SR) imaging quality is significantly smaller than the designed FOV of the baseline optical system. In this paper, we investigate the influence of various aberrations on the SR properties of a telescopic system using a low sidelobe five-ring pure phase pupil modulator. On this basis, we propose an optimal design method for a wide FOV and a large-aperture telescopic baseline optical system with uniform image quality and a particular residue of symmetric aberration. The design results show that when the optimized 4 m aperture baseline optical system and the modulator are combined as the imaging system, the imaging system has a round and very similar point spread function in the FOV range of 0.28°; the SR gain ratio is 1.234-1.254; and the highest sidelobe intensity is less than 0.1; thus, the system maintains a high resolution ratio and a low sidelobe energy throughout the entire FOV. Finally, a reasonable tolerance model of the baseline optical system is established. The central symmetry tolerances are observed to be loose in this model, thereby reducing the cost and manufacturing difficulty of the system.
Environment variation is an important factor affecting the polarization propagation through the smoke. In this paper, we investigate the effects of the relative humidity and optical thickness on polarization transmission character, as well as the persistence of the linear and circular polarization of artificial smoke particles with simulations and experiments. We develop an environment modulation system to control the environment variation and measure the transmission degree of polarization (DOP). Correspondingly, by building the relation between the smoke filling time and optical thickness, as well as between the relative humidity and particle size and refractive index, we utilize the Monte Carlo program to track photon scattering process through varying the radius, refractive index and optical thickness. Both the simulation and the experimental results show that the DOP of both linear and circular polarizations are constantly decreased with the increasing of the optical thickness. However, at the same optical thickness, both the linear and circular polarization's persistence benefits with the increasing of the relative humidity. Moreover, circular polarization persists better than linear polarization in the larger optical thickness and the higher humidity environment under the wavelength of 532 nm. These works can verify the persistence of circular polarization and broaden the application range of polarized lights in a variable artificial smoke environment.
We present both simulated and experimental methods to show the propagation of linear and circular polarization under a settling smoke environment. Simulations and experiments were performed for artificial smoke with typical visible wavelengths under light and a moderate settling smoke environment. Using the Monte Carlo method, we simulate polarization propagation with the particle size, refractive index, wavelength, and the optical length under the settling smoke. Through the real-time measurement of optical length during the settling, the relationship of the settling environment parameters in the experiment and the simulation is established to improve the delay problem of the traditional parameters' measurement. Both the experimental and the simulated results show that with the increase of the concentration the degree of polarization of the four types of polarization is constantly decreased during the settling. Circular polarization persists better than linear polarization with the higher concentration, and the longer the wavelength, the better the persistence of the circular polarization. This study expands the application range of polarization under a settling smoke environment.
