Correction algorithm of the frequency-modulated continuous-wave LIDAR ranging system.

Frequency-modulated continuous-wave LIDAR has broad application prospects. Compared with the traditional pulse LIDAR, the FMCW LIDAR has the advantages of high resolution and long measurement distance. But it still can be affected by several factors, including environmental noise, spectrum aliasing, spectrum leakage and other issues. Some traditional filtering algorithms or signal transformation algorithms can improve the above problems, but the effect is not ideal. This paper proposes a signal correction algorithm called the VMD-based refined cross-power spectral density algorithm (VRCPSD). This algorithm is based on signal decomposition denoising and improved spectrum refinement methods. The algorithm applies variational mode decomposition, spectrum refinement and cross-power spectral density to signal processing. The VRCPSD algorithm is compared with the traditional spectrum correction algorithm on the high-speed linear array APD FMCW LIDAR experimental platform. The results show that the VRCPSD algorithm has a better spectrum correction effect on the LIDAR experimental platform. This algorithm can reduce the margin of error to the centimeter level. Therefore, the algorithm is promising in that it can improve the signal waveform of the FMCW laser radar ranging system, make the spectrum get better correction and make the distance more accurate.

Modeling and simulations of a three-dimensional ghost imaging method with differential correlation sampling.

The quality of depth maps acquired by a time-of-flight three-dimensional ghost imaging (3DGI) system is limited by dynamic ambient light and electrical noise. We developed a novel method that integrates the differential-correlation-sampling (DCS) method and a modulated continuous-wave laser source to realize the 3DGI and reduce the noise influence. The simulation results for the proposed method, DCS-3DGI, verify its feasibility. The analysis of mean-square-error, peak signal-to-noise ratio, structural similarity index measure, and edge preservation index demonstrates a superior anti-interference performance than conventional 3DGI methods.

FMCW Laser Fuze Multiple Scattering Model and Accurate Fixed-Distance Algorithm in a Smoke Environment.

In a smoke environment, suspended particles can scatter and absorb laser photons, making target echo signals extremely weak and difficult to extract and identify, which causes obvious difficulty in fixed-distance of laser fuze. In this paper, the multiple scattering model of frequency-modulated-continuous-wave (FMCW) laser fuze in a smoke environment was established. This model simulates multi-path propagation and multiple scattering of photons. At the same time, we use the correntropy spectral density (CSD) algorithm for accurate fixed-distance of FMCW laser fuze. The absolute error of distance does not exceed 0.15 m in smoke interference environment.

CCDC103 as a Prognostic Biomarker Correlated with Tumor Progression and Immune Infiltration in Glioma.

Background: The Coiled-coil domain-containing proteins (CCDCs) are expressed in many cancers, but the role of Coiled-coil domain-containing protein 103 (CCDC103) in cancers remains unclear. Further investigations are necessary to ascertain its diagnostic significance and understand its biological function in cancers. This study aims to elucidate the biological functionalities of CCDC103 in glioma and evaluate the correlation between CCDC103 expression with glioma progression. Methods: Clinical data on glioma patients were acquired from The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA), and the Gene Expression Omnibus (GEO). The evaluation encompassed the examination of correlations between CCDC103 expression, pathological characteristics, and clinical outcomes. Furthermore, the analysis included the assessment of the correlations between CCDC103 expression and immune cell infiltration as well as glioma progression. Results: Gliomas have higher levels of CCDC103 expression than the para-carcinoma tissues. Poorer prognosis, unfavorable histological characteristics, the absence of IDH gene mutations, and the absence of chromosome 1p and 19q deletions were all associated with higher expression of CCDC103 in gliomas. In addition to patient age, tumor grade, the absence of IDH mutations, and the absence of chromosome 1p and 19q deletions, univariate and multivariate Cox analyses showed that CCDC103 expression was independently prognostic of overall survival, disease-free survival, and progression-free survival in patients with glioma. Furthermore, tumor infiltration of B cells, neutrophils, macrophages, and dendritic cells were all linked with elevated expression of CCDC103. High CCDC103 expression was linked to immune response-related signaling pathways and cell proliferation, according to gene set enrichment analysis (GSEA). Notably, the knockdown of CCDC103 in glioma cell lines resulted in a significant reduction in cell proliferation and migration. Conclusion: The correlation between CCDC103 expression and both glioma progression and immune cell infiltration implies that CCDC103 expression holds promise as a valuable prognostic biomarker for glioma.

The effects of hypothermia on glutamate and γ-aminobutyric acid metabolism during ischemia in monkeys: a repeated-measures ANOVA study.

During an ischemic stroke, the brain releases various factors, including glutamate and γ-aminobutyric acid. Glutamate can cause neurotoxic effects through certain receptors and exacerbate neurological damage, while γ-aminobutyric acid as an inhibitory neurotransmitter can antagonize the excitotoxic effects of glutamate and enhance the tolerance of neurons to ischemia. Therefore, in this study, the content of amino acid neurotransmitters in brain tissue before ischemia, after 10 min of ischemia, hypothermic perfusion, and rewarming were analyzed by high-performance liquid chromatography-UV in an animal model of ischemic stroke generated by blocking the bilateral common carotid arteries of rhesus monkeys. The changes in amino acid neurotransmitters in the rhesus monkey brain during post-ischemia hypothermic perfusion and rewarming were investigated by statistical methods of repeated measures ANOVA, showing that the concentration change of glutamate had not only a temporal factor but also was influenced by temperature, and there was an interaction effect between the two. Time but not temperature affected the change in γ-aminobutyric acid concentration, and there was an interaction effect between the two. Accordingly, hypoperfusion exerts a protective effect during ischemia by inhibiting the release of excitatory amino acid neurotransmitters, while the antagonistic effect of GABA on Glu is not significant.

NCAPG as a Novel Prognostic Biomarker in Glioma.

Background: Non-SMC condensin I complex subunit G (NCAPG) is expressed in various human cancers, including gliomas. However, its biological function in glioma remains unclear. The present study was designed to determine the biological functions of NCAPG in glioma and to evaluate the association of NCAPG expression with glioma progression. Methods: Clinical data on patients with glioma were obtained from The Cancer Genome Atlas (TCGA), the Chinese Glioma Genome Atlas (CGGA), the Gene Expression Omnibus (GEO), and the Rembrandt and Gravendeel databases. The correlations among NCAPG expression, pathological characteristics, and clinical outcome were evaluated. In addition, the correlations of NCAPG expression with immune cell infiltration and glioma progression were analyzed. Results: NCAPG expression was higher in gliomas than in adjacent normal tissues. Higher expression of NCAPG in gliomas correlated with poorer prognosis, unfavorable histological features, absence of mutations in the isocitrate dehydrogenase gene (IDH), absence of chromosome 1p and 19q deletions, and responses to chemoradiotherapy. Univariate and multivariate Cox analysis demonstrated, in addition to patient age, tumor grade, absence of IDH mutations, and absence of chromosome 1p and 19q deletions, NCAPG expression was independently prognostic of overall survival, disease-free survival, and progression-free survival in patients with glioma. In addition, high expression of NCAPG correlated with tumor infiltration of B cells, CD4+ T cells, CD8+ T cells, neutrophils, macrophages, and dendritic cells. Gene set enrichment analysis (GSEA) indicated that high NCAPG expression was associated with cell proliferation and immune response-related signaling pathways. NCAPG knockdown in glioma cell lines significantly reduced cell survival, proliferation, and migration. Conclusion: NCAPG expression correlates with glioma progression and immune cell infiltration, suggesting that NCAPG expression may be a useful prognostic biomarker for glioma.