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Triggering lysosome‐regulated immunogenic cell death (ICD, e.g., pyroptosis and necroptosis) with nanomedicines is an emerging approach for turning an “immune‐cold” tumor “hot”—a key challenge faced by cancer immunotherapies. Proton sponge such as high‐molecular‐weight branched polyethylenimine (PEI) is excellent at rupturing lysosomes, but its therapeutic application is hindered by uncontrollable toxicity due to fixed charge density and poor understanding of resulted cell death mechanism. Here, a series of proton sponge nano‐assemblies (PSNAs) with self‐assembly controllable surface charge density and cell cytotoxicity are created. Such PSNAs are constructed via low‐molecular‐weight branched PEI covalently bound to self‐assembling peptides carrying tetraphenylethene pyridinium (PyTPE, an aggregation‐induced emission‐based luminogen). Assembly of PEI assisted by the self‐assembling peptide‐PyTPE leads to enhanced surface positive charges and cell cytotoxicity of PSNA. The self‐assembly tendency of PSNAs is further optimized by tuning hydrophilic and hydrophobic components within the peptide, thus resulting in the PSNA with the highest fluorescence, positive surface charge density, cell uptake, and cancer cell cytotoxicity. Systematic cell death mechanistic studies reveal that the lysosome rupturing‐regulated pyroptosis and necroptosis are at least two causes of cell death. Tumor cells undergoing PSNA‐triggered ICD activate immune cells, suggesting the great potential of PSNAs to trigger anticancer immunity.

 

The cold chain (refrigerated supply chain) is an important application of refrigeration technologies. The capacity of the cold chain industry is growing rapidly in emerging economies such as China, leading to significant environmental impacts, especially greenhouse gas (GHG) emissions. By conducting the literature review, this study begins with presenting a comprehensive overview of the cold chain industry in China. We observed that China has a large total cold warehouse capacity but low capacity per capita. Then, we directly link the example of the cold chain in China to the methods of evaluating the GHG emissions from the cold chain industry. It is observed that existing studies either primarily focus on the lifecycle of food with less consideration on the cold chain facilities or primarily focus on the lifetime of a certain stage of the cold chain (e.g., refrigerated transportation) with less consideration on food. Neither frameworks capture the entire cold chain system. Moreover, we argue that existing studies lack investigations of the cold chain GHG emissions on the national scale. To evaluate the overall GHG emissions, we recommended that one can use the bottom-up approach. First, use the lifecycle assessment (LCA) to estimate the single-unit level (e.g., one kg food, one particular refrigerated warehouse) cold chain emissions. Second, aggregate up to the national scale by the distribution patterns of the cold chain networks. Finally, we identify the crucial future issues regarding collecting cold chain lifecycle inventory data, investigating the cold chain network and the overall environmental impacts in China, regulation and technology needs for expanding the clean refrigeration technologies, and the implications of the cold chain development to water, land, and society.

 

In recent years, organic dye molecules as photosensitizers have played a significant role in the field of dye-sensitized solar cells. In this context, two primary dihydroindolocarbazole-based organic dyes (sk201 and sk202), which were synthesized recently by Song et al., and three further designed dyes (DMZ1-3) were theoretically investigated based on density functional theory and time-dependent density functional theory. Molecular geometries, absorption spectra, charge transfer, molecular electrostatic potential and nonlinear optical properties were quantificationally studied and visually presented to reveal the relationships between the molecular structures and performances of dyes. The effects of joining the isolated dyes and TiO2 on the molecular absorption spectra and energy levels were analyzed. Moreover, several parameters, such as efficiency of light-harvesting, driving forces of electron regeneration and injection, excited-state lifetime and vertical dipole moment, were calculated to give the multi-angle demonstrations of the photovoltaic performances for these dyes.