No abstract

No abstract

Supramolecular nanomedicines have shown great merits in cancer therapy, but their clinical translation is hampered by monotonous therapeutic modality and unsatisfactory antitumor performance. Herein, a hybrid supramolecular polymeric nanomedicine (SNPs) is developed based on β‐cyclodextrin/camptothecin (CPT) host−guest molecular recognition and iron‐carboxylate coordination. Iron ions stabilizing SNPs catalyze the conversion of intracellular hydrogen peroxide into highly toxic hydroxyl radical through a Fenton reaction, which further cleaves the thioketal linker of the supramolecular monomer to release potent CPT, thus amplifying the therapeutic efficacy by combining chemodynamic therapy and chemotherapy. The combination therapy stimulates antitumor immunity and promotes intratumoral infiltration of cytotoxic T lymphocytes by triggering immunogenic cell death. In synergy with PD‐L1 checkpoint blockade, SNPs enables enhanced immune therapy and a long‐term tumor remission.

No abstract

Polymeric cylinders, a fascinating type of nanostructures with high surface area, internal volume and rigidity, have been exploited as novel drug delivery vehicles over the past decade. However, it's still an open challenge to afford cylindrical nanostructures using polymeric building blocks via traditional self‐assembly processes. Herein, we report a hierarchical self‐assembly strategy of preparing cylindrical aggregates (tubisomes) from an amphiphilic supramolecular bottlebrush polymer in which a cyclic peptide nanotube is employed as the noncovalent backbone. Additionally, an aggregation‐induced emission (AIE) effect was introduced into the tubisomes to endow them with excellent fluorescent properties. Intriguingly, by encapsulating with the anticancer drug doxorubicin (DOX), both the fluorescence of tubisome and DOX can be quenched due to the energy transfer relay (ETR) effect. The release of DOX can induce the interruption of the ETR effect and recover the silenced fluorescence, thereby permitting the in‐situ imaging of drug release. The AIE‐featured supramolecular tubisomes reported here provide an alternative approach for fabricating cylindrical polymeric nanostructures and holds great potential for imaging‐guided drug delivery.

Vehicular sensor network (VSN) using vehicle-based sensors is an emerging technology that can provide an inexpensive solution for surveillance and urban monitoring applications. For the constantly moving vehicles, resulting in unpredictable network topology, data transmission in VSN is vulnerable to packet losses, thus deteriorating the surveillance quality. To resolve this problem, a cooperative data sampling and compression approach is proposed. Based on compressive sensing, this approach does not require inter-sensor communication and adopts sparse random projections to remove redundancy in spatially neighbouring measurements. It is experimentally shown that the proposed algorithm provides fairly accurate reconstruction of the field under surveillance, and incurs much less communication traffic load compared to conventional sampling strategies. Practical data sets, including the temperature distribution in Beijing and the global position system (GPS) tracking data of over 6000 taxis in the city, are used in our experiments to verify the reconstruction accuracy and energy efficiency of the scheme. Different vehicular mobility models are also employed to study the impact of movement behavior. Simulation results show that our proposed approach outperforms the conventional sampling and interpolation strategy, which propagates data in uncompressed format, by 5 dB in reconstruction quality and by 50% in communication complexity reduction for the same sampling rate.

No abstract

The diffusion behaviors of Co clusters on clean ZnO(0001)-Zn single crystal surface and their magnetic properties are studied. Co clusters are deposited on the clean ZnO(0001)-Zn surface at room temperature and then undergone ultrahigh vacuum annealing until fully reconstructed. The replacement of Zn2+ by Co2+ is confirmed by scanning tunneling microscopy and x-ray photoelectron spectroscopy. The Co doped ZnO shows a weak ferromagnetism at room temperature with a saturation magnetic moment of 1.08 μB/Co. Our observations indicate that surface Zn vacancies facilitate Co diffusion, and the interplay of Co ion with internal O vacancies leads to the ferromagnetism.