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Abstract Wastewater treatment, particularly for persistent organic pollutants (POPs), remains a significant challenge. Although advanced oxidation processes (AOPs) currently used for treating POPs can achieve a decent efficiency, they often involve high costs and necessitate additional post‐treatment processes. Here, a jellyfish‐mimicking, multi‐functional living material encapsulating algae cells are presented, namely Algelly, created using a multi‐material digital‐light processing (DLP) bioprinting technique. The Algelly construct comprises a methacrylated alginate (AlgMA) layer designed to support algae growth, and a poly(N‐isopropylacrylamide) (PNIPAM) layer embedded with magnetic nanoparticles (MNs). The MNs enable the Algelly to respond to near‐infrared (NIR) laser for deformation and magnetic force for steering. It is demonstrated that the DLP bioprinting technique can fabricate the heterogeneous Algelly with high spatial resolution and efficiency, which supports subsequent algae proliferation and effective photosynthesis in the Algelly matrix. Moreover, the NIR‐induced thermo‐responsive deformation and magnetic steering capabilities enhance Algelly's adaptability for recycling and collection. Most importantly, Algelly demonstrates a high efficiency in degrading POPs under white light illumination. Therefore, it is believed that Algelly holds a promising potential for new applications in wastewater treatment, given its efficiency in POP decomposition and flexible location control capabilities. 

Wide-area soil moisture sensing is a key element for smart irrigation systems. However, existing soil moisture sensing methods usually fail to achieve both satisfactory mobility and high moisture estimation accuracy. In this paper, we present the design and implementation of a novel soil moisture sensing system, named as SoilId, that combines a UAV and a COTS IR-UWB radar for wide-area soil moisture sensing without the need of burying any battery-powered in-ground device. Specifically, we design a series of novel methods to help SoilId extract soil moisture related features from the received radar signals, and automatically detect and discard the data contaminated by the UAV's uncontrollable motion and the multipath interference. Furthermore, we leverage the powerful representation ability of deep neural networks and carefully design a neural network model to accurately map the extracted radar signal features to soil moisture estimations. We have extensively evaluated SoilId against a variety of real-world factors, including the UAV's uncontrollable motion, the multipath interference, soil surface coverages, and many others. Specifically, the experimental results carried out by our UAV-based system validate that SoilId can push the accuracy limits of RF-based soil moisture sensing techniques to a 50% quantile MAE of 0.23%. 

Abstract Controllable and long‐term release remains a great challenge in current drug delivery systems. Benefiting from their efficient drug loading and painless administration, microneedles (MNs) have emerged as a promising platform for transdermal drug delivery, while they often fail to achieve long‐term tissue adhesion and controllable extended drug release. Here, 3D printing of an innovative MN patch is presented with succulent‐inspired responsive microstructures and light‐controllable long‐term release capability. The MN exhibits a reversible shrink‐swell volume change behavior in response to surrounding humidity, which enables sufficient mechanical strength for skin penetration under the shrinkage conditions and efficient long‐term adhesion when swollen in skin tissues. Moreover, the MN patch introduces a controllable long‐term drug release system, achieved through the integration of thiolated heparin (Hep‐SH) for sustained growth factor release and graphene oxide (GO) nanosheets for controlled drug release via near infrared (NIR) laser irradiation. The MN patches with growth factor loading have good biocompatibility and can promote the proliferation, migration, and proangiogenesis of endothelial cells is further demonstrated. Thus, it is believed that such flexible MN patches can be promising candidates for controllable long‐term transdermal drug delivery as well as other related tissue engineering applications.