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Chemoimmunotherapy, which integrates chemotherapeutic drugs with immune modulators, has emerged as a promising approach to enhance the generally lackluster clinical outcomes of immunotherapy. Nevertheless, a significant challenge lies in orchestrating multiple events associated with diverse mechanisms that activate antitumor immune responses. Here, a novel approach utilizing dual‐responsive covalent organic frameworks (COFs) co‐encapsulating doxorubicin (DOX) and programmed cell death ligand‐1 (PD‐L1) siRNA (siPD‐L1), termed RDAP, is presented for synergistic chemoimmunotherapy. In this system, COFs modified with poly‐L‐lysine (PLL) can adsorb DOX within their porous structure and bind siPD‐L1 onto their surface via electrostatic interactions. The resulting RDAP formulation can escape from lysosome via the "proton sponge effect" and undergo rupture upon exposure to azoreductase, leading to the efficient release of DOX and siPD‐L1 into the cytoplasm of 4T1 cells. The RDAP, harboring dual therapeutic agents, can effectively eliminate tumor cells and trigger significant immunogenic cell death (ICD) through DOX. Additionally, it concomitantly suppresses PD‐L1 expression in tumor cells, thereby significantly enhancing the antitumor immune response and resulting in synergistically improved antitumor efficacy. In mouse models, RDAP demonstrated exceptional efficacy in eliminating both primary and distant tumors, along with a pronounced antimetastatic effect against 4T1 murine breast‐to‐lung metastasis. [ABSTRACT FROM AUTHOR]

The regulation of glial cell activation is a critical step for the treatment or prevention of neuroinflammation‐based brain diseases. However, the development of therapeutic drugs that pass the blood–brain barrier (BBB) and inhibit the glia cell activation remains a significant challenge. Herein, an ultrasmall 2D vanadium carbide quantum dots (V2C QDs) that are capable of crossing the BBB are prepared, and the admirable anti‐neuroinflammatory effects are presented. The prepared 2D V2C QDs with an average size of 2.54 nm show good hydrophilicity, physiological stability, and effective BBB‐crossing ability. The biological effect of V2C QDs on inflammatory reactions demonstrates fascinating results in preventing the impairment of learning and memory in BALB/c mice stimulated by lipopolysaccharide. Investigation of molecular mechanism reveals that V2C QDs not only inhibit the toll‐like receptor 4/myeloid differentiation factor 88‐mediated nuclear factor kappa B and mitogen‐activated protein kinase pathways, but also prevent eukaryotic translation initiation factor 2α/activating transcription factor 4/C/EBP homologous protein‐signaling pathway and reduce oxidative stress via activating the NF‐E2‐related factor‐2/heme oxygenase‐1‐signaling pathway, leading to greatly inhibited activation of microglia and astrocytes and weakened production of inflammatory cytokines. In summary, V2C QDs exert potent anti‐inflammatory effects through multiple pathways, thus offer great potential for the treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

To overcome the shortage of common method of invariable feedback time, a scheme using improved invariable feedback time of the reference current is proposed to reduce the error of the voltage-to-frequency converter. With the same circuit resolution, the feedback time is increased by 1.8 times. The linearity accuracy of designed converter using new method can be better than 0.005 0% in the full scale of output frequency -- 200~200 kHz. [ABSTRACT FROM AUTHOR]

Semihydrogenation of alkynes to produce alkenes is very important in the industry; however, over‐hydrogenation heavily complicates the postprocesses, which are highly energy consuming and not environmentally friendly. One of the most efficient pathways to solve this challenging issue is to develop highly selective catalysts that could only hydrogenate alkynes and are inactive in hydrogenation of alkenes. This work presents herein an efficient catalyst, consisting of in situ created PdS0.53 nanoparticles as the redox‐active sites inside the defect pores of metal–organic framework UiO‐66, which demonstrates very high alkene selectivity (up to 99.5%) in semihydrogenation of easily over‐hydrogenated terminal alkynes. In contrast to the traditional catalysts, strict control over the reaction time becomes the nonessential condition because the catalyst system is almost inactive in hydrogenation of alkenes. Therefore, this paradigm work provides a practically applicable pathway for the development of efficient catalysts with unique catalytic properties for selective semihydrogenation reactions. [ABSTRACT FROM AUTHOR]