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Efficient therapeuic proteins’ delivery into mammalian cells and subcellular transport (e.g., fast escape from endolysosomes into cytoplasm) are two key biological barriers that need to be overcome for antigen-based immunotherapy and related biomedical applications. For those purposes, we designed a novel kind of photoresponsive polypeptide-glycosylated poly­(amidoamine) (PAMAM) dendron amphiphiles (PGDAs), and their synthesis, UV-responsive self-assembly, and triggered ovalbumin (OVA) release have been fully investigated. The highly anisotropic PGDA4 with a glycosylated second-generation PAMAM dendron self-assembled into stable polypeptide vesicles (polymersomes) within 20–50 wt % water, which exhibited UV-responsive reassembly, dynamic binding with a lectin of concanavalin A, and an accelerated OVA release in vitro. Moreover, upon 365 nm UV irradiation, the self-assembled polymersomes of those glycopolypeptides were transformed into micellar aggregates in aqueous solution at pH 7.4 but disassembled completely at pH 5. The OVA-loaded polymersomes could efficiently deliver OVA into RAW264.7 cells and achieve enhanced endolysosomes escape upon UV irradiation, as revealed by flow cytometry and confocal laser scanning microscopy (CLSM). Furthermore, the enzyme-linked immunosorbent assay (ELISA) showed that the blank sugar-coated polypeptidosomes activated a high level of tumor necrosis factor α (TNF-α) of 468 pg/mL, playing a better role of immune adjuvant for activating the macrophages. Upon the UV irradiation with a dose of 3 J/cm2, the OVA-loaded polymersomes could further stimulate RAW264.7 and enhance the TNF-α level by about 45%. Consequently, this work provides a versatile platform to construct photosensitive and sugar-coated polymersomes of glycopolypeptides that have potential applications for protein delivery, immune adjuvant, and antigen-based immunotherapy.

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A planar slotted patch antenna is proposed for ground penetrating radar (GPR). The proposed antenna has a wide bandwidth ranging from 600 MHz to 4 GHz. Tapered slot feeding, curved ground plane, and slot loading are used for a wideband operation, whereas resistive loading is utilized for removal of notch band. Current loops made by slots are bifurcated with the use of 50 Ω resistors. The antenna is designed and optimized to achieve good performance, especially at lower frequencies while keeping the antenna's physical dimension relatively small. The time-domain analysis of the antenna is performed, and the comparative graph is added after analysis to validate its performance in the impulse-based radar. Furthermore, a sandbox test is conducted; the experimental results show the significance of the proposed antenna toward GPR application. K E Y W O R D S ground penetrating radar, planar antenna, resistively loaded antenna, wideband

A new planar antenna is proposed for multiple applications in ground‐penetrating radar. The proposed antenna offers ultra‐wide band characteristics ranging from 100 MHz to 6 GHz. The antenna composed of two elements: an electrical tree‐shaped portion and a magnetic loop antenna, made by joining an electrical antenna with a ground plane via 50 Ohm resistor. The loop antenna portion provides a low‐frequency operation without increasing physical size of the antenna. Proposed antenna has relatively small dimensions 20 × 22.5 cm2 as compared with similar antennas covering the same bandwidth. Time domain analysis of this antenna is done to check its performance for applications in impulse‐based radar systems. The antenna has been manufactured and experimental results are added to validate simulation results.

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Uncovering the underlying kinetics mechanism of the charge carrier during the transfer process is of fundamental importance in pursuing outstanding photocatalytic activity. However, it still remains a challenge owing to the rapid reaction rate of the charge carrier on the surface of photocatalysts. Here, in situ single-molecule fluorescence microscopy is employed to study the photoelectron-transfer kinetics in real time for an individual TiO2-tipped carbon nanotube (TiO2-tipped CNT) using a redox-responsive fluorogenic probe. A visual transport process for electron transfer from TiO2 nanoparticles to CNT is obviously observed via single-molecule fluorescence imaging. Based on the fluorescent product formation rate, the kinetics information of the photoelectron-transfer process can be obtained. The kinetics analysis results show that heterogeneity of catalytic activity caused by the photoelectron reactive sites exists in an individual TiO2-tipped CNT heterostructure, which is always masked in the ensemble measurement. After applying an adaptive high-resolution algorithm, which considers temporal and spatial factors into consideration simultaneously, the dynamic heterogeneity of special location on CNT within the TiO2-tipped CNT heterostructure in product formation is revealed with 40 nm spatial resolution. Moreover, we prove that the photoelectron-transfer distance on CNT can be up to 16.82 μm. These results give a deep insight into the kinetics information of the photoelectron-transfer process and a policy toward designing better photocatalysts.