8 research outputs found

    Multi-frame blind deconvolution of atmospheric turbulence degraded images with mixed noise models

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    This paper proposes a mixed noise model and uses the multi-frame blind deconvolution to restore the images of space objects under the Bayesian inference framework. To minimize the cost function, an algorithm based on iterative recursion was proposed. In addition, three limited bandwidth constraints of the point spread functions were imposed into the solution process to avoid converging to local minima. Experimental results show that the proposed algorithm can effectively restore the turbulence degraded images and alleviate the distortion caused by the noise

    Pheophorbide A–Mediated Photodynamic Therapy Potentiates Checkpoint Blockade Therapy of Tumor with Low PD–L1 Expression

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    Although the immune checkpoint blockade (ICB) has made a great success in cancer immunotherapy, the overall response rate to the ICB, such as anti–programmed death ligand 1 (PD–L1) therapy, remains only at 20–30%. One major reason is the low expression level of the immune checkpoint in a certain type of tumor cells and its insufficient activation of the host immune system. Herein, we reported a cyclic RGD (cRGD)–modified liposomal delivery system loading the anti–PD–L1 antibody and the photosensitizer pheophorbide A (Pa), allowing a targeting of the low PD–L1 expressing 4T1 mouse breast cancer cells through the recognition of an overexpression of αvβ3 integrin on the tumor cells. The Pa–mediated photodynamic therapy (PDT) elevated the expression of PD–L1 on the tumor cells. PDT, in combination with the anti–PD–L1 therapy, promoted the activation and maturation of dendritic cells as well as the infiltration of cytotoxic T lymphocytes, resulting in the augmented antitumor immune response for the enhanced therapeutic effect. These results demonstrated the combined therapeutic effects of PDT and ICB on the tumor with low PD–L1 levels. Our study suggested that an increase in the PD–L1 expression in tumor cells by PDT would be a promising adjuvant treatment to overcome the ICB irresponsiveness

    A rationally designed cancer vaccine based on NIR-II fluorescence image-guided light-triggered remote control of antigen cross-presentation and autophagy

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    Cancer vaccines represent a promising immunotherapeutic treatment modality. The promotion of cross-presentation of extracellular tumor-associated antigens on the major histocompatibility complex (MHC) class I molecules and dendritic cell maturation at the appropriate time and place is crucial for cancer vaccines to prime cytolytic T cell response with reduced side effects. Current vaccination strategies, however, are not able to achieve the spatiotemporal control of antigen cross-presentation. Here, we report a liposomal vaccine loading the second near-infrared window (NIR-II, 1000–1700 nm) fluorophore BPBBT with an efficient photothermal conversion effect that offers an NIR-light-triggered endolysosomal escape under the imaging guidance. The NIR-II image-guided vaccination strategy specifically controls the cytosolic delivery of antigens for cross-presentation in the draining lymph nodes (DLNs). Moreover, the photothermally induced endolysosomal rupture initiates autophagy. We also find that the adjuvant simvastatin acts as an autophagy activator through inhibiting the PI3K/AKT/mTOR pathway. The light-induced autophagy in the DLNs together with simvastatin treatment cooperatively increase MHC class II expression by activating autophagy machinery for dendritic cell maturation. This study presents a paradigm of NIR-II image-guided light-triggered vaccination. The approach for remote control of antigen cross-presentation and autophagy represents a new strategy for vaccine development

    In Vivo Imaging Tracking and Immune Responses to Nanovaccines Involving Combined Antigen Nanoparticles with a Programmed Delivery

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    Combined nanovaccine can generate robust and persistent antigen-specific immune responses. A combined nanovaccine was developed based on antigen-loaded genipin-cross-linked-polyethyleneimine–antigen nanoparticles and in vivo multispectral fluorescence imaging tracked the antigen delivery of combined nanovaccine. The inner layer antigen nanoparticles carried abundant antigens by self-cross-linking for persistent immune response, whereas the outer antigen on the surface of antigen nanoparticles provided the initial antigen exposure. The delivery of combined nanovaccine was tracked dynamically and objectively by the separation of inner genipin cross-linked antigen nanoparticle and the outer fluorescent antigen. The immune responses of the combined nanovaccine were evaluated including antigen-specific CD4<sup>+</sup> and CD8<sup>+</sup> T-cell responses, IgG antibody level, immunological memory, and CD8<sup>+</sup> cytotoxic T lymphocyte responses. The results indicated that the inner and outer antigens of combined vaccine can be tracked in real time with a programmed delivery by the dual fluorescence imaging. The programmed delivery of the inner and outer antigens induced strong immune responses with a combination of a quick delivery and a persistent delivery. With adequate antigen exposure, the dendritic cells were effectively activated and matured, and following T cells were further activated for immune response. Compared with a single nanoparticle formulation, the combined nanovaccine exactly elicited a stronger antigen-specific immune response

    Pyrolysis and Co-Combustion of Semi-Dry Sewage Sludge and Bituminous Coal: Kinetics and Combustion Characteristics

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    To reduce the energy consumption and cost of the drying of sewage sludge (SS) and to ensure stability during combustion, the pyrolysis and co-combustion characteristics of semi-dry SS after the dehydration of flocculant and bituminous coal (BC) were studied in this work. The results show that the decrease in moisture content accelerates the release of volatile substances, and the increase in heating rate can also enhance the release of water and volatile matters. Furthermore, in the co-combustion of semi-dry SS and BC, the increase in mixing ratio (from 0% to 60%) of semi-dry SS caused the ignition and burnout temperature to decrease from 481 °C to 214 °C and from 702 °C to 627 °C, respectively. During co-combustion, the infrared spectra showed that the temperature range of 300–700 °C was the main gas precipitation area, and the main gaseous products were CO2, NOx, SO2, and volatile organic pollutants (VOCs)

    Pyrolysis and Co-Combustion of Semi-Dry Sewage Sludge and Bituminous Coal: Kinetics and Combustion Characteristics

    No full text
    To reduce the energy consumption and cost of the drying of sewage sludge (SS) and to ensure stability during combustion, the pyrolysis and co-combustion characteristics of semi-dry SS after the dehydration of flocculant and bituminous coal (BC) were studied in this work. The results show that the decrease in moisture content accelerates the release of volatile substances, and the increase in heating rate can also enhance the release of water and volatile matters. Furthermore, in the co-combustion of semi-dry SS and BC, the increase in mixing ratio (from 0% to 60%) of semi-dry SS caused the ignition and burnout temperature to decrease from 481 &deg;C to 214 &deg;C and from 702 &deg;C to 627 &deg;C, respectively. During co-combustion, the infrared spectra showed that the temperature range of 300&ndash;700 &deg;C was the main gas precipitation area, and the main gaseous products were CO2, NOx, SO2, and volatile organic pollutants (VOCs)
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