RESUMO
Based on the x-ray absorption edges of different elements, we simultaneously image and distinguish the composition of three differently shaped components of an object by using energy-resolved x-ray absorption ghost imaging (GI). The initial x-ray beam is spatially modulated by a series of Hadamard matrix masks, and the object is composed of three pieces of Mo, Ag, and Sn foil in the shape of a triangle, square, and circle, respectively. The transmitted x-ray intensity is measured by an energy-resolved single-pixel detector with a spectral resolution better than 0.8 keV. Through correlation of the transmission spectra with the corresponding Hadamard patterns, the spectral image of the sample is reconstructed, with a spatial resolution of 108 µm. Our experiment demonstrates a practical application of spectral ghost imaging, which has important potential for the noninvasive analysis of material composition and distribution in biology, medical science, and many other fields.
RESUMO
A novel, to the best of our knowledge, cross-spectral optical computing imaging experiment has been achieved through a single exposure of a charge-coupled device. The experimental setup integrates single-pixel imaging (SPI) with ghost imaging (GI) through a photoelectric conversion circuit and a synchronous modulation system. The experimental process involves modulation in one wavelength band (in SPI) and demodulation using the GI algorithm in another. Significantly, our approach utilizes optical computing demodulation, a departure from the conventional electronic demodulation in GI (SPI), which involves the convolution between the bucket optical signals and the modulated patterns on the digital micromirror device. A proof-of-concept cross-band imaging experiment from near-infrared to visible light has been carried out. The results highlight the system's ability to capture images at up to 20 frames per second using near-infrared illumination, which are then reconstructed in the visible light spectrum. This success not only validates the feasibility of our approach but also expands the potential applications in the SPI or GI fields, particularly in scenarios where two-dimensional detector arrays are either unavailable or prohibitively expensive in certain electromagnetic spectra such as x-ray and terahertz.
RESUMO
This study was to investigate the inhibitory activity of small hairtail-related peptides (VFEVFW, LPNSLYQQ, LPNSLYQK, and FADAME) on intracellular monoamine oxidase-A (MAO-A) and their protective effects in a cell model. Specifically, the inhibition activity in SH-SY5Y cells indicated that VFEVFW and LPNSLYQK reduced â¼50% of MAO-A activity in cells, at 0.5 m m. The survival experiment demonstrated that the toxic effect of dexamethasone (DEX) on cells can be significantly alleviated in the presence of peptides, and these peptides can restore (>20%) the mitochondrial membrane potential of SH-SY5Y cells reduced by DEX. Circular dichroism displayed that peptides affected the secondary structure of MAO-A in a concentration-dependent manner. Finally, the real-time quantitative polymerase chain reaction assay revealed that the MAO-A inhibitory activity of the peptides was associated with the upregulation of brain derived neurotrophic factor/cAMP (Cyclic adenosine monophosphate) response element binding protein)/B-cell lymphoma-2 mRNA levels.
Assuntos
Monoaminoxidase , Neuroblastoma , Humanos , Monoaminoxidase/genética , Monoaminoxidase/metabolismo , Monoaminoxidase/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Inibidores da Monoaminoxidase/metabolismo , Linhagem Celular Tumoral , Neuroblastoma/genética , Neuroblastoma/metabolismo , Neurônios , Peptídeos/farmacologiaRESUMO
By solving the (2 + 1) dimensional Schrödinger equation in free space, we find that the autofocusing off-axis hollow vortex Gaussian beams (HVGBs) are analytically derived for the first time. The off-axis HVGBs can be adjusted by changing the off-axis coordinate (x0,y0) and topological charge n2. In particular, by increasing the off-axis coordinate (x0,y0), the self-focusing intensity can be increased. Besides, the self-focusing property can be more obvious. Furthermore, by increasing the hollow order n1, we can deepen the depth of focus, make the focus position further away, and increase the self-focusing intensity too. We also discuss other propagation properties that are used to enrich the autofocusing off-axis HVGBs, such as Poynting vector, angular momentum, gradient force, and maximum scattering force during propagation.
RESUMO
Based on the extended Huygens-Fresnel principle, analytical formulas for the cross-spectral density matrix elements of a partially coherent electromagnetic rotating elliptical Gaussian vortex (PCEREGV) beam through non-Kolmogorov turbulence are derived and the corresponding second-order statistics are investigated numerically. The numerical calculations of the PCEREGV beam are first developed to validate the correctness of the analytical results. Our findings show that the transverse spectrum density with an initially elliptical annular shape splits into two light spots during the beam propagation. By choosing appropriate parameters of the beam and the turbulence, we can maximize the spectrum density and control the spectral states of coherence and polarization so as to alleviate the influence of the turbulent atmosphere effectively.
RESUMO
We study the paraxial propagation of the radially polarized Airy beams (RPAiBs) in uniaxial crystals orthogonal to the optical axis analytically and numerically. The propagation trajectory, the intensity and the radiation forces of the RPAiBs are investigated and the properties are elucidated by numerical examples in this paper. Results show that the RPAiBs evolve into the beams produced by the x-direction electric field (RPAiXBs) and the y-direction electric field (PRAiYBs) which are totally different in uniaxial crystals. During the propagation, the intensity of the RPAiXBs transfers from the side lobe in the x-direction to the main lobe and finally returns to the side lobe in the x-direction again, but that of the RPAiYBs transfers from the side lobe in the y-direction to the main lobe and flows to the side lobe in the x-direction at last. The effect of the intensity focusing for the RPAiXBs can be modulated by the ratio of the extraordinary index (ne) to the ordinary index (no) in anisotropic medium, which contributes to the intensity focusing of the RPAiBs in a short distance a lot. We can adjust the intensity distribution especially the focusing position, the propagation trajectory and the radiation forces distributions of the RPAiXBs through choosing an appropriate value of the ratio of ne to no to meet the actual usage accordingly.
RESUMO
We introduce the propagation of the first-order chirped Airy vortex beams (FCAiV) in a chiral medium analytically. Results show that the FCAiV beams split into the left circularly polarized vortex (LCPV) beams and the right circularly polarized vortex (RCPV) beams, which have totally different propagation trajectories in the chiral medium. In this paper, we investigate the effects of the first-order chirped parameter ß, the chiral parameter γ and the optical vortex on the propagation process of the FCAiV beams. It is shown that the propagation trajectory of the FCAiV beams declines with the chirped parameter increasing. Besides, the increase of the chiral parameter acting on the LCPV beams makes the relative position between the main lobe and the optical vortex further while the effect on the RCPV beams is the opposite. Furthermore, the relative position between the main lobe and the optical vortex contributes to the position of the intensity focusing. Meanwhile, with the chiral parameter increasing, the maximum gradient and scattering forces of the LCPV beams decrease but those of the RCPV beams will increase during the propagation. It is significant that we can control the propagation trajectory, the intensity focusing position and the radiation forces of the FCAiV beams by varying the chirped parameter and the chiral parameter.
RESUMO
AIM: This study aimed to identify the molecular type and prognostic model of lung adenocarcinoma (LUAD) based on cancer stem cell-related genes. Studies have shown that cancer stem cells (CSC) are involved in the development, recurrence, metastasis, and drug resistance of tumors. METHOD: The clinical information and RNA-seq of LUAD were obtained from the TCGA database. scRNA dataset GSE131907 and 5 GSE datasets were downloaded from the GEO database. Molecular subtypes were identified by ConsensusClusterPlus. A CSC-related prognostic signature was then constructed via univariate Cox and LASSO Cox-regression analysis. RESULT: A scRNA-seq GSE131907 dataset was employed to obtain 11 cell clusters, among which, 173 differentially expressed genes in CSC were identified. Moreover, the CSC score and mRNAsi were higher in tumor samples. 18 of 173 genes were survival time-associated genes in both the TCGA-LUDA dataset and the GSE dataset. Next, two molecular subtypes (namely, CSC1 and CSC2) were identified based on 18 survival-related CSC genes with distinct immune profiles and noticeably different prognoses as well as differences in the sensitivity of chemotherapy drugs. 8 genes were used to build a prognostic model in the TCGA-LUAD dataset. High-risk patients faced worse survival than those with a low risk. The robust predictive ability of the risk score was validated by the time-dependent ROC curve revealed as well as the GSE dataset. TIDE analysis showed a higher sensitivity of patients in the low group to immunotherapy. CONCLUSION: This study has revealed the effect of CSC on the heterogeneity of LUAD, and created an 8 genes prognosis model that can be potentially valuable for predicting the prognosis of LUAD and response to immunotherapy.