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Construction land expansion is a key driver of urbanization and industrialization, yet it poses the risk of losing farmland and cascading impacts on food supply. The spatial characteristics of farmland occupied by construction land and its association with grain yield in China were unclear. We analyzed the characteristics of farmland converted into construction land, and its relationship with grain yield in China for 2000–2020. Construction land increased in area in central and western regions of China, and farmland decreased in area in southeastern China. The expansion of construction land in the North China Plain, Northeast China Plain, and the Loess Plateau, occurred at the expense of farmland. Except the southeast coast of China, grain yield increase was only weakly dependent on farmland area. Patterns in which farmland was converted into construction land and grain-yield change were highly coupled in southeastern coastal China, Sichuan Basin, Shandong Peninsula, and the Hu Huanyong Line. It should be noted that expansion in construction land area does have some influence on grain production; ultimately it is greatly affected by yield per unit area.

Photochromic materials with rapid color-switching, long color retention times, and rewritability are crucial for meeting the requirements of future rewritable ink-free media. However, these requirements are challenging to satisfy simultaneously due to the inherent constraints among these features. Herein, a novel photochromic nanofiber nonwoven fabric was designed and constructed based on a conjugated organic–inorganic hybrid structure through electrospinning and hot-pressing techniques. The as-prepared fabric can change color in merely 5 s under UV irradiation and can reach saturation within 2 min. In addition, upon the introduction of a potent metal chelator, its color retention time exceeds 14 days under ambient conditions, significantly longer than that of most rewritable materials recently reported (several hours to 5 days). Moreover, the fabric exhibits high writing resolution and can be photoprinted and heat-erased for over 100 cycles while still retaining 96% of its initial reflectivity. Hydrophobic thermoplastic polyurethane provides the fabric with excellent waterproof and antifouling properties, thus preventing the composite from swelling or collecting graffiti due to moisture or dust. This work exploits a competitive approach for designing flexible, rewritable, and superior functional wearables with practical applications.

To develop intelligent wearable protection systems is of great significance to human health engineering. An ideal intelligent air filtration system should possess reliable filtration efficiency, low pressure drop, healthcare monitoring function, and man–machine interactive capability. However, no existing intelligent protection system covers all these essential aspects. Herein, we developed an intelligent wearable filtration system (IWFS) via advanced nanotechnology and machine learning. Based on the triboelectric mechanism, the fabricated IWFS exhibits a long-lasting high particle filtration efficiency and bacteria protection efficiency of 99% and 100%, respectively, with a low-pressure drop of 5.8 mmH2O. Correspondingly, the charge accumulation of the optimized IWFS (87 nC) increased to 3.5 times that of the pristine nanomesh, providing a significant enhancement of the particle filtration efficiency. Theoretical principles, including the enhancement of the β-phase and the lower surface potential of the modified nanomesh, were quantitatively investigated by molecular dynamics simulation, band theory, and Kelvin probe force microscopy. Furthermore, we endowed the IWFS with a healthcare monitoring function and man–machine interactive capability through machine learning and wireless transmission technology. Crucial physiological signals of people, including breath, cough, and speaking signals, were detected and classified, with a high recognition rate of 92%; the fabricated IWFS can collect healthcare data and transmit voice commands in real time without hindrance by portable electronic devices. The achieved IWFS not only has practical significance for human health management but also has great theoretical value for advanced wearable systems.

The immunosuppressive tumor microenvironment (ITME) of osteosarcoma (OS) poses a significant obstacle to the efficacy of existing immunotherapies. Despite the attempt of novel immune strategies such as immune checkpoint inhibitors and tumor vaccines, their effectiveness remains suboptimal due to the inherent difficulty in mitigating ITME simultaneously from both the tumor and immune system. The promotion of anti‐tumor immunity through the induction of immunogenic cell death and activation of the cGAS‐STING pathway has emerged as potential strategies to counter the ITME and stimulate systemic antitumor immune responses. Here, a bimetallic polyphenol‐based nanoplatform (Mn/Fe‐Gallate nanoparticles coated with tumor cell membranes is presented, MFG@TCM) which combines with mild photothermal therapy (PTT) for reversing ITME via simultaneously inducing pyroptosis in OS cells and activating the cGAS‐STING pathway in dendritic cells (DCs). The immunostimulatory pathways, through the syngeneic effect, exerted a substantial positive impact on promoting the secretion of damage‐associated molecular patterns (DAMPs) and proinflammatory cytokines, which favors remodeling the immune microenvironment. Consequently, effector T cells led to a notable antitumor immune response, effectively inhibiting the growth of both primary and distant tumors. This study proposes a new method for treating OS using mild PTT and immune mudulation, showing promise in overcoming current treatment limitations. Here, a bimetallic polyphenol‐based nanoplatform is presented that combines with mild photothermal therapy (PTT) for reversing the immunosuppressive tumor microenvironment (ITME) via simultaneously inducing pyroptosis in osteosarcoma (OS) cells and activating the cGAS‐STING pathway in dendritic cells (DCs). The syngeneic effect of these immunostimulatory pathways significantly benefited DCs maturation, thereby remodeling OS immune microenvironment for better antitumor immune response.

Naturally crosslinked carbonaceous liquid metal aqueous printable ink mediated by biopolymers.E-textile with conductivity, stability, wearability, and aesthetic characteristics.Multi-applications in health monitoring, pressure sensing, and energy harvesting.

Flexible and stretchable triboelectric nanogenerators (TENGs) have been rapidly advanced owing to the demand for portable and wearable electronic devices that can work under universal or motional circumstances. While versatile materials can be applied in a TENG as dielectric materials, flexible and cost-effective electrodes are crucially important for the output performance of TENGs. Herein, we developed a poly(vinyl alcohol) (PVA) hydrogel TENG doped with a novel two-dimensional material, graphitic carbon nitride (g-C3N4), which could act as both a cost-effective flexible electrode and a positive dielectric for TENG with different morphologies. The measured peak-to-peak open-circuit voltage of the TENG reached 80 V at a dopant concentration of 2.7 wt % in single-electrode mode, which is far higher than that of the pristine PVA hydrogel TENG. As a demonstration of the application, the g-C3N4/PVA hydrogel TENG can be adopted as electronic skin to monitor the movement of the human body. Low-frequency mechanical energy-harvesting devices in different morphologies including discoid flake shape, tube shape, and spiral shape in the single-electrode mode or contact-separation mode have been designed, fabricated, and evaluated. All of these merits of the proposed hydrogel TENG after doping two-dimensional (2D) material g-C3N4have demonstrated their promising potential for versatile applications in biomechanical energy harvesting and self-powered sensing.

Stretchable electronic textiles have integrated seamlessly into our lives, promising advancements in health monitoring and intelligent wearables. However, one key challenge is to combine fibrous materials and functional materials to realize an integrity of stretchability and functionality by a simple and scalable method. To address this challenge, we propose a novel hierarchically buckled porous microstructure fabric (HBPMFs) via a surface self-assembly method, which can integrate with customized functional nanoparticles for tailorable wearable energy devices. The unique buckled porous microstructure endows HBPMFs with remarkable porous stretchability and high loading capacity of functional nanoparticles. Based on HBPMFs, triboelectric nanogenerators (HBPMFs-TENGs) with high structural integrity, stretchability and enhanced electrical outputs are design and fabricated. The as-made Ag@HBPMFs-TENG exhibits a greater enhancement in voltage by 4 times than the original fabric TENG, which can drive miniature wearable electronics. The features enable the Ag@HBPMFs-TENG in efficiently powering wearable electronics and acting as a self-powered sensor capable of detecting human motions. This work will offer a new insight for porous stretchable energy devices by designing unique microstructural surfaces on commercial fibrous materials.

Triboelectric nanogenerators (TENGs) are widely used as a novel kind of sustainable energy harvesting technique. The materials used for TENGs are diverse that include polymers, metals, inorganic and composite materials, etc. However, most of these materials are not recyclable and thus may potentially cause environmental problems. Therefore, this review aims to summarize and discuss sustainable TENGs based on recyclable materials that are largely in line with the sustainable development of our society. Specifically, this review summarizes the current progress in recycled materials based TENGs (RM-TENGs), involving the design, fabrication, evaluation and application of TENGs that are made from recycled materials. First, the current recycling methods for recycled materials are overviewed and the basic procedures in practice are outlined. Then, the energy harvesting and sensing applications of RM-TENGs are critically reviewed and discussed under different classifications of recycled materials. Their potential applications are also demonstrated. Finally, we provide perspectives on the challenges and potential solutions associated with the next-generation recycled-material based TENGs. Using recycled materials to fabricate TENG can break through the existing material limitations of TENGs, and more importantly, create a high level of sustainability by generating sustainable and renewable energies from waste materials.

Synthetic organogels/hydrogels are attracting growing interests due to their potential applications in biomedical fields, organic electronics, and photovoltaics. Photogelation methods for synthesis of organogels/hydrogels have been shown particularly promising because of the high efficiency and simple synthetic procedures. This study synthesized new biodegradable polyhydroxyalkanoates (PHA)-based organogels/hydrogels via UV photo-cross-linking using unsaturated PHA copolymer poly[(R)-3-hydroxyundecanoate-co-(R)-3-hydroxy-10-undecenoate] (PHU10U) with polyethylene glycol dithiol (PDT) as a photo-cross-linker. The PHU10U was synthesized by an engineered Pseudomonas entomophilaand characterized via Fourier transform infrared spectroscopy, 1H nuclear magnetic resonance (NMR), and 13C NMR. With decreasing the molar ratio of PHU10U to PDT, both the swelling ratio and pore size were decreased. Meanwhile, increasing densities of the gel networks resulted in a higher compressive modulus. Cell cytotoxicity studies based on the CCK-8 assay on both the PHU10U precursor and PHU10U/PDT hydrogels showed that the novel PHA-based biodegradables acting as hydrogels possess good biocompatibility.

Triboelectric nanogenerators (TENGs) are green energy devices that can convert mechanical energy into electrical energy. However, lower output power density currently hinders its realistic applications. Introducing functional materials into dielectric polymers layer is an efficient approach to enhance TENG output. Herein, a low-cost, biocompatible Prussian blue analog (KxMn[FeCN)6]y·zH2O, MnFePBA) is proposed as a functional component for high-performance hybrid tribomaterials of TENGs. Numerous highly polar CN groups found in MnFePBA can interact dipole-dipole with the C-F bond in PVDF, promoting the formation of electroactive β-phase PVDF and enhancing the capacity for charge induction and charge capture. Simultaneously, the weak interface fusion between the inorganic material and the organic polymer can be improved as the O-H bond in MnFePBA can establish a stronger hydrogen bond with the C-F bond in PVDF. Additionally, high dielectric MnFePBA can enhance the dielectric properties of PVDF/MnFePBA to boost the TENG output. Consequently, the PVDF/MnFePBA can achieve evidently increased short-circuit current of 31.2 µA, output voltage of 1580 V and ultra-high power density of 12.8 W/m2(4 ×4 cm2). Moreover, the assembled TENG could also be efficiently utilized for human motion capture and sensing applications. This work enriches the range of functional components for high-performance tribomaterials of TENGs.

A promising new concept is the application of flexible and foldable conductive film or paper for wearable electronics, in which silver nanowires, carbon nanotubes, and graphene are primarily used as conductive materials. However, their insufficient nanostructure contacts lead to poor electrical conductivity and mechanical fracture. Here, we demonstrate a simple and innovative strategy for fabricating a free-standing silver film with inverted pyramids by replicating pyramids on a textured silicon wafer under a hydrothermal reaction. In this unique structure, the inverted pyramids on the film surface can provide sufficient buffer space for a mechanically foldable and unfoldable cushion, and the continuous film ensures an uninterrupted electron transport pathway. As a result, the silver film with inverted pyramids can exhibit extremely high conductivity, with a sheet resistance as low as 2.55 × 10–3Ω/sq, corresponding to an electrical conductivity of 4.2 × 105S cm–1for a 9.2-μm-thick film (67.7% of bulk silver’s conductivity). Surprisingly, this film has outstanding mechanical folding stability, with less than a 0.5% deviation from the initial resistance after 35,000 repetitive folding and unfolding cycles when tested at the folding site. The film is free-standing, thin, flexible, foldable, and suitable for cutting and patterned growth, which makes it suitable for wearable electronics, showing a much wider range of applications than substrate-based ones.

The growing demand for the sustainable energy supply of portable wearable electronic devices has recently attracted much attention. The emergence of an environmentally friendly, renewable, and sustainable energy-supplying triboelectric nanogenerator (TENG) provides new potential and promising solution. However, it requires excellent structural stability and superior properties in practical applications. In this paper, a novel flexible corrugated triboelectric nanogenerator (C-TENG) with incredible elasticity, excellent durability and output performance for efficient energy harvesting and self-powered sensing has been designed and developed. For enhancement of electric performance, a study has also been carried out for investigating different structural parameters for the optimized performance of C-TENGs. The as-made C-TENGs have shown excellent and stable electric performance, outstanding mechanical durability and washing capability. The highly self-resilient structure of C-TENG enables its open-circuit voltage, short-circuit current, and power density to reach 480 V, 137 μA and 486 μW/cm2, respectively. Furthermore, the functional applications of C-TENG as smart insoles and intelligent carpets have been demonstrated. An intelligent system has also been developed to detect human motion and monitor people's stream scale on the intelligent carpet. This study proposes a new perspective for the structural design of TENGs and advanced applications in intelligent sensing.

Osteoarthritis (OA) is characterized by cartilage degradation and subchondral bone remodeling. However, most available studies focus on either cartilage degradation or subchondral bone lesion, alone, and rarely pay attention to the synergy of these two pathological changes. Herein, a dual-functional medication is developed to simultaneously protect cartilage and achieve subchondral bone repair. Black phosphorus nanosheets (BPNSs), with a strong reactive oxygen species (ROS)-scavenging capability and high biocompatibility, also present a notable promoting effect in osteogenesis. BPNSs efficiently eliminate the intracellular ROS and, thus, protect the inherent homeostasis between cartilage matrix anabolism and catabolism. RNA sequencing results of BPNSs-treated OA chondrocytes further reveal the restoration of chondrocyte function, activation of antioxidant enzymes, and regulation of inflammation. Additional in vivoassessments solidly confirm that BPNSs inhibit cartilage degradation and prevent OA progression. Meanwhile, histological evaluation and microcomputed tomography (micro-CT) scanning analysis verify the satisfying disease-modifying effects of BPNSs on OA. Additionally, the excellent biocompatibility of BPNSs enables them as a competitive candidate for OA treatment. This distinct disease-modifying treatment of OA on the basis of BPNSs provides an insight and paradigm on the dual-functional treatment strategy focusing on both cartilage degradation and subchondral bone lesion in OA and explores a broader biomedical application of BPNS nanomedicine in orthopedics.

Triboelectric nanogenerators (TENGs), which can harvest low-frequency mechanical energy from human activities, are potential for wearable electronics, especially textile-based TENGs. Besides triboelectric performance, wearable comfort, like air permeability, is crucial for wearable electronics. However, the textile-based TENGs integrated with high performance and wearable comfort still remain challenging. Here, we construct the open porous architected PDMS coatings on fabric for breathable fabric-based TENG (oPF-TENG) based on the synergistic effect of insoluble NaCl, DBP and soluble silicone oil. The open porous structure constitutes the airflow channel with the air permeability of ∼73 mm/s. Meanwhile, the porous structure and the PVDF filler enhance the triboelectric output. The open circuit voltage, short circuit current and power density of oPF-TENG reach ∼600 V, ∼15 μA and 5.67 W/m2, respectively. The as-made oPF-TENG with good air permeability and triboelectric output can not only contribute to the human body energy harvesting but also show potential for wearable self-powered sensing.

Accompanying the boom in smart wearable electronics, triboelectric nanogenerators (TENGs) as burgeoning mechanical-to-electrical harvesters have drawn expanding interest. In this study, a kind of novel flexible, high-output TENGs with PAN/FCNT as tribopositive layer and PVDF/PDMS/TiO2as tribonegative layer have been designed and developed. For a synergistic effect, PAN and PVDF possessing strongly polar -CN and -F groups are handpicked as dielectric hosts to ensure maximum charge induction and triboelectrification. Highly conductive FCNT is introduced into the insulated PAN tribopositive layer, serving as the charge transport path to reduce surface charge loss. Additional PDMS is beneficial to strengthen the triboelectronegativity of PVDF tribonegative layer, and engaged as the charge trapping sites to diminish electro-discharge in air. TiO2is employed as filler to build an inorganic-organic (TiO2-PVDF/PDMS) composite dielectric layer because of its triple functions of potent electron capture, high dielectric constant, and promoting the formation of electroactive β-phase PVDF. Meanwhile, the hydrogen bonds between PVDF, TiO2with semi-crosslinked PDMS can stabilize interface and enhance friction output. Consequently, the assembled TENGs exhibit an ultra-high peak-to-peak voltage of 2088 V and a maximum output power of 7.2 W/m2, which shows promising applications in energy supplying and self-powered sensing fields.

Self-powered electronic textiles (e-textiles) and triboelectric nanogenerators (TENGs) have been explored for the development of energy-harvesting facilities which provide sustainable power supplements for portable, wearable, and low-energy electronics. However, it requires the features of excellent structural stability and superior capability in sensing applications. In this study, we present and develop a new kind of fabric-rebound triboelectric nanogenerator (FR-TENG) that could be used for efficient energy harvesting and self-powered sensing. For improvement of electric performance, a systematic study has also been carried out to investigate various structural parameters for the property optimization of FR-TENGs. The as-made FR-TENG has shown stable electric performance in energy harvesting, cyclic washing capability, and mechanical durability. The full-textile structure of FR-TENG enhances its adaptability and rebound ability, and the open-circuit voltage, short circuit current and power density of the FR-TENG reach up to 418.09 V, 65.85 μAand 199.14 μW⋅cm−2, respectively. Furthermore, the FR-TENGs are used as smart carpets to build up a self-powered, wireless and intelligent system for monitoring human motions. This study proposes a new perspective for an all-textile TENGs and shows the advanced human-machine software interface in sensing applications.

With rapid advancement in wearable electronics, textile-based triboelectric nanogenerators (T-TENGs) have attracted great attention for energy harvesting and bio-motion sensing because of their softness, lightweight, and comfort properties. However, the interface bonding between functional materials and textile substrate, and the compatibility with manufacturing still face considerable challenges. Herein, a kind of scalable core–spun coating yarn-based triboelectric nanogenerators (CSCY-TENGs) with a hierarchical architecture is designed and developed via continuous manufacturing which integrates yarn spinning, coating and braiding technologies to achieve fully continuous production. In this method, spinning technology was used to spin a kind of conductive core-spun yarns with silver-plated nylon yarn (SNY) as core and insulating cotton fibers as shell, where SNY serves as electrode and cotton fibers serve as base materials for absorbing/coating with triboelectric materials. Then multiple core-spun yarns coated with nylon and doped polydimethylsiloxane are used as positive and negative triboelectric materials to realize hierarchical CSCY-TENGs by braiding technology. The CSCY-TENGs can be washed and compatible with industrial-scale manufacturing. Besides, it can achieve an output voltage of 174 V, and a peak power density and an average power density of 275 mW/m2and 57 mW/m2respectively. As demonstration, the CSCY-TENG can charge various commercial capacitors and power low-power electronics. It can also be used as an anti-theft alarm carpet and energy harvesting shoes for bio-motion detection and energy harvesting.

β-Hydroxybutyrate (3HB) is a small molecule produced as a ketone body in mammalian animals. It has been found that 3HB provides not only energy for a body, it also participates in cell signal transduction events as a signal molecule. This study focuses on investigation of 3HB immunomodulatory mechanisms. Proteomic analysis indicates a new post-translational modification of β-hydroxybutyrylation (Kbhb) on antibodies. Because of the low level of Kbhb antibodies and the associated difficulty in purifying them, simulated Kbhb antibody was produced using chemical modification in vitro. The chemically modified Kbhb antibody was shown to improve the stability of antibodies to protease and heat treatments. Furthermore, Kbhb of antibodies stabilizes the antibodies in plasma. As a remarkable example, COVID-19 neutralizing antibody B38 produced by 293T cells was Kbhb modified and stabilized in vivo, providing a strategy for the possibility of extending the protection effects of COVID-19 antibodies.