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PtII based organometallic photosensitizers (PSs) have emerged as novel potent photodynamic inactivation (PDI) reagents through their enhanced intersystem crossing (ISC) processes. Currently, few PtII PSs have been investigated as antibacterial materials, with relatively poor performances reported and with structure‐activity relationships not well described. Herein, a pair of configurational isomers are reported of Bis‐BODIPY (4,4‐difluoro‐boradizaindacene) embedded PtII PSs. The cis‐isomer (cis‐BBP) displayed enhanced 1O2 generation and better bacterial membrane anchoring capability as compared to the trans‐isomer (trans‐BBP). The effective PDI concentrations (efficiency > 99.9%) for cis‐BBP in Acinetobacter baumannii (multi‐drug resistant (MDR)) and Staphylococcus aureus are 400 nM (12 J cm−2) and 100 nM (18 J cm−2), respectively; corresponding concentrations and light doses for trans‐BBP in the two bacteria are 2.50 µM (30 J cm−2) and 1.50 µM (18 J cm−2), respectively. The 50% and 90% minimum inhibitory concentration (MIC50 and MIC90) ratio of trans‐BBP to cis‐BBP is 22.22 and 24.02 in A. baumannii (MDR); 21.29 and 22.36 in methicillin resistant S. aureus (MRSA), respectively. Furthermore, cis‐BBP displays superior in vivo antibacterial performance, with acceptable dark and photoinduced cytotoxicity. These results demonstrate cis‐BBP is a robust light‐assisted antibacterial reagent at sub‐micromolecular concentrations. More importantly, configuration of PtII PSs should be an important issue to be considered in further PDI reagents design. [ABSTRACT FROM AUTHOR]

The polarised Bidirectional Reflectance Distribution Function (pBRDF) model relates the properties of target materials to the polarisation information of the incident and reflected light. The Priest–Germer (P-G) model was the first strictly pBRDF model to be officially released; however, some shortcomings remain. In this study, we first analyse the assumption framework of the P-G model, analyse the assumption framework to determine the imperfections in the framework, supplement the boundary conditions of the model for diffraction and transmission effects, and propose and construct a polarised pBTDF model based on the existing P-G model and parameter inversion; the output results of the model are compared with the experimental data through simulation. The results show that the intensity relative error and Degree of Linear Polarisation relative error of the target can be reduced by more than 40%, using the improved model, proving its accuracy and precision. [ABSTRACT FROM AUTHOR]

OBJECTIVE: This study aims to investigate the effect of nimodipine combined with betahistine on the levels of CRP and other inflammatory cytokines, as well as vascular endothelial function in patients with hypertensive cerebral vasospasm. METHODS: A total of 80 patients with hypertensive cerebral vasospasm from March 2016 to September 2018 were enrolled and randomly equally divided into two groups. At 1 week before enrollment, the application of all antihypertensive drugs was stopped. Then amlodipine tablets were used in control group, based on which nimodipine tablets were applied in observation group. All the patients included were followed up for 1 month. The changes in the cerebral vasospasm index in the course of treatment as well as inflammatory cytokines and indicators related to vascular endothelial function at 1 month after treatment were measured and compared between the two groups. The correlations of the cerebral vasospasm index with the changes in inflammatory cytokines and vascular endothelial function-related factors in the body were analyzed. Finally, the effective rates of blood pressure regulation and cerebral vasospasm treatment were compared, while the adverse reactions and the overall clinical treatment effect of the two groups were evaluated. RESULTS: The cerebral vasospasm indexes in observation group were significantly lower than those in control group at 3 d, 1 week and 1 month after treatment (p < 0.05). At 1 month after treatment, the levels of inflammatory cytokines such as high-sensitivity C-reactive protein (hs-CRP), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in observation group were significantly reduced compared to those in control group (p < 0.05). As for vascular endothelial function-related indicators, the endothelin-1 (ET-1) level in observation group was markedly lower than that in control group, whereas the level of nitric oxide (NO) was statistically higher than that in control group (p < 0.05). The cerebral vasospasm index was statistically positively correlated with changes in hs-CRP, IL-6, TNF-α and ET-1 (p < 0.05), but negatively correlated with changes in NO (p < 0.05). Besides, the effective rates of blood pressure regulation and cerebral vasospasm treatment in observation group were significantly higher than those in control group (p < 0.05). The overall treatment effective rate in observation group was markedly higher than that in control group (p < 0.05), and there were no significant differences of adverse reactions between the two groups (p > 0.05). CONCLUSION: For the treatment of hypertensive cerebral vasospasm, combined application of betahistine on the basis of nimodipine can effectively reduce the body's aseptic inflammatory responses, improve vascular endothelial function and increase the cerebral circulation blood flow, which offers a favorable strategy for clinical therapy. [ABSTRACT FROM AUTHOR]

• The reflection process of the target surface is investigated from a microscopic perspective. Developed A polarization characteristics model to illustrate the link between the properties of the target surface and the degree of polarization of the reflected light. The polarization of the target is greatest in the direction of specular reflection and smallest in the direction of light source incidence. • Experimental data are used to invert the complex refractive index of the target. This suggests that the established Polarimatric Bidirectional Reflectance Distribution Function model can provide theoretical support for the analysis of the polarization properties of the target surface. • Targets of different materials have different polarization properties and the extinction coefficient can effectively classify the targets. Traditional imaging detection techniques are used to collect intensity information and spectral information of the target to generate high-resolution target images, but the imaging system is susceptible to external environmental factors, resulting in system instability and image quality degradation. Polarization detection techniques use the polarization properties of light to determine the polarization state and spatial profile of a target, thereby improving the contrast of the target in the image. In this study, the reflection process of the target surface is investigated from a microscopic perspective. A polarization characteristics model was developed to illustrate the link between the properties of the target surface and the degree of polarization of the reflected light. The results show that the degree of polarization is strongly related to the detection of zenith and azimuth angles. Experimental data are used to invert the complex refractive index of the target. The polarization of the target is greatest in the direction of specular reflection and smallest in the direction of light source incidence. This suggests that the established Polarimatric Bidirectional Reflectance Distribution Function (pBRDF) model can provide theoretical support for the analysis of the polarization properties of the target surface. Targets of different materials have different polarization properties and the extinction coefficient can effectively classify the targets. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

• A new method for preparing non spherical particles (burning Ganoderma spores method) has been proposed. • A polarized light simulation transmission model based on T-matrix was established in a smoke simulation environment. • Conducted quantitative and qualitative model validation experiments. In order to deal with the problem of serious pollution caused by non-spherical particles, this study developed and obtained a non-spherical medium based on the theoretical basis of polarized optics and a new non-spherical particle preparation method (burning Ganoderma lucidum spores method). A polarized light simulation transport model based on the T-matrix was established by applying it to the smoke simulation environment. Using this polarization transmission model, simulation experiments were conducted to determine the effects of wavelength, polarization state, optical thickness and various transmission media on the Degree of Polarization (DOP). The simulation results show that both incoming linearly and circularly polarized light undergo depolarization as the optical thickness increases; however, the depolarization of circularly polarized light becomes more severe. In addition, the DOP in the non-spherical particle medium is always larger than that in the spherical particle medium, which indicates that the circularly polarized light is superior to the linearly polarized light in terms of deflection precession. [ABSTRACT FROM AUTHOR]

The pBRDF model is able to relate the properties of target materials to the polarization information of incident and reflected light, and is an important basis for obtaining polarization information of targets in space. It is an important basis for obtaining target polarization information and polarization detection of space targets. P-G model is the first strictly pBRDF model officially released, but there are still deficiencies. In this paper, we first analyze the assumption framework of the P-G model, derive the imperfections in the framework through the analysis of the assumption framework, and add scattering and phase function to enhance the existing model. On the basis of the existing P-G model and parameter inversion, the output results of the model are compared with the experimental data through simulation, and the results show that the relative error of the target's linear polarizability is reduced under the improved model, which proves the accuracy and precision of the improved model. [ABSTRACT FROM AUTHOR]

The pBRDF model is able to relate the properties of target materials to the polarization information of incident and reflected light, and is an important basis for obtaining polarization information of targets in space. It is an important basis for obtaining target polarization information and polarization detection of space targets. P-G model is the first strictly pBRDF model officially released, but there are still deficiencies. In this paper, we first analyze the assumption framework of the P-G model, derive the imperfections in the framework through the analysis of the assumption framework, and add scattering and phase function to enhance the existing model. On the basis of the existing P-G model and parameter inversion, the output results of the model are compared with the experimental data through simulation, and the results show that the relative error of the target's linear polarizability is reduced under the improved model, which proves the accuracy and precision of the improved model. [ABSTRACT FROM AUTHOR]