RESUMO
The spaceborne dispersive spectrometer is widely used in environmental, resource, and ocean observations. The coded spectrometer has higher energy advantages than the dispersion spectrometer, so it has great application prospects. In the current study, we developed an off-axis short-wave infrared coded optical system (SICOS) based on curved prism dispersion, and we further explored the design and optimization of the SICOS structure. Finite element analyses of a space-based short-wave infrared coded spectrometer based on curved prism dispersion (SSICS-CPD), including static simulation, modal analysis, sinusoidal vibration mechanical analysis, and random vibration mechanical analysis, were carried out. Simulation results showed that the SICOS support structure had excellent mechanical and thermal stability. As off-axis optical systems cannot meet the requirements of optical position accuracy through centering processing, a point source microscope and three-coordinate measuring machines were employed to complete the high-precision and rapid assembly of the SSICS-CPD. In addition, verification tests of surface shape error, stress relief, random vibration, and optical design parameters were carried out to validate the high stability and imaging performance of the SSICS-CPD. Results showed that the average modulation transfer function in the full field was 0.43 at 16.67 lp/mm, the spectral smile was <0.2 pixels, and the spectral keystone was <0.1 pixels. The design, analysis, assembly, and verification of the SSICS-CPD provide a useful reference for the development of other spaceborne prism dispersion spectrometers.
RESUMO
OBJECTIVE: This study aims to test the serum levels of soluble thrombomodulin (TM) in patients with chronic kidney disease (CKD)3-5 and to assess their connection with the different stages and severity of disease. METHODS: Sixty-seven patients with CKD are included, disease severity was evaluated accordingly to CKD staging and clinical data is collected. Nineteen healthy volunteers served as healthy controls. Serum soluble TM is analyzed by ELISA. RESULTS: The levels of soluble TM in all patients with CKD were significantly higher than those of healthy controls (p < 0.001). CKD5 patients showed higher serum levels of soluble TM, in comparison to CKD4 patients (p = 0.001), CKD3 patients (p < 0.001), and healthy controls (p < 0.001). The correlation analysis revealed significant correlation between serum soluble TM and disease severity (r = 0.714, p < 0.001). Serum soluble TM was found to be correlated with eGFR (r = -0.766; p < 0.001) and serum creatinine (r = 0.778, p < 0.001). CONCLUSION: Soluble TM concentrations significantly increase in the CKD patients and are associated with the severity of the disease. Soluble TM may play critical roles in the development of CKD, as a biomarker of endothelial cells damage, anticoagulation and anti-inflammation.