With the booming development of flexible electronics, the need for a multifunctional and high-performance strain sensor has become increasingly important. Although significant progress has been made in designing new microstructures with sensing capabilities, the tradeoff between sensitivity and workable strain range has prevented the development of a strain sensor that is both highly sensitive and also stretchable. Here, a wrinkle-assisted crack microstructure is designed and fabricated via prestretching the multiwalled carbon nanotubes ink (CNTs ink)/polyurethane yarn (PU yarn). This designed structure originates from the mismatch in Young’s modulus and elasticity between the CNTs ink and PU yarn during the stretching process. The structure endows the sensor with combined characteristics of a high sensitivity toward stretching strain (gauge factor of 1344.1 at 200% strain), an ultralow limit of detection (<0.1% strain), excellent durability (>10 000 cycles), a wide workable strain range (0–200%), and outstanding response and stability toward bending deformation. This high-performance strain sensor will see widespread improved performance across applications such as intelligent fabrics, electrical skins, and fatigue detection for full-range human motion monitoring.

Uncertainties remain in the potential of forest plantations to sequestrate carbon (C). We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests). Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha−1 in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age (<25 years vs. ≥25 years), stand types (broadleaved vs. coniferous and deciduous vs. evergreen), tree species origin (native vs. exotic) of plantations, land-use history (afforestation vs. reforestation) and site preparation for plantations (unburnt vs. burnt), and study regions (tropic vs. temperate). The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation.

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Adopting a holistic three-step literature review workflow, a total of 1,639 journal articles were used in this study as the literature sample related to recycled aggregate (RA). This study summarized the existing research topics focusing on RA, gaps of current research, suggestions for promoting RA usage, and research directions for future work. A research framework was also proposed linking the existing research themes into trends in RA research. This review work serves as a foundation work to bridge the gap between scientific research and industry practice, as well as to guide the directions in RA-related academic work using an interdisciplinary approach.

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Microbial methanogenesis in anaerobic soils contributes greatly to global methane (CH4) release, and understanding its response to temperature is fundamental to predicting the feedback between this potent greenhouse gas and climate change. A compensatory thermal response in microbial activity over time can reduce the response of respiratory carbon (C) release to temperature change, as shown for carbon dioxide (CO2) in aerobic soils. However, whether microbial methanogenesis also shows a compensatory response to temperature change remains unknown. Here, we used anaerobic wetland soils from the Greater Khingan Range and the Tibetan Plateau to investigate how 160 days of experimental warming (+4°C) and cooling (−4°C) affect the thermal response of microbial CH4 respiration and whether these responses correspond to changes in microbial community dynamics. The mass-specific CH4 respiration rates of methanogens decreased with warming and increased with cooling, suggesting that microbial methanogenesis exhibited compensatory responses to temperature changes. Furthermore, changes in the species composition of methanogenic community under warming and cooling largely explained the compensatory response in the soils. The stimulatory effect of climate warming on soil microbe-driven CH4 emissions may thus be smaller than that currently predicted, with important consequences for atmospheric CH4 concentrations.

Energy absorbing is an important and desirable property in mechanical and civil engineering. Here, a proof-of-concept method is presented as a new approach to achieve artificial mechanical materials with tunable compressive behavior for energy absorbing constructed from unit cells with a snap fit structure. The artificial structure undergoes a series of stable configurations derived from the sequential insertion of the plug into the groove of the snap fit. Both, experimental and simulation results manifest the multi-stable and tunable mechanical properties of the structure. The mechanical energy dissipated by the proposed structure is demonstrated to be dependent on the lead-in angle of the snap fit and the deflection ratio of the groove, as well as on the coefficient of friction between the plug and the groove of the snap fit. The system designed, herein, exhibits mechanical properties that can be tuned not only by adjusting the geometric parameters, but also by tuning the coefficient of friction between the plug and the groove, allowing the mechanical properties to be tailored post-fabrication. Furthermore, the proposed model can be extended to the macro-, micro-, or nanoscales. These findings provide a simple method to obtain artificial materials with tunable energy absorbing properties, which can be applied in areas such as the design of automobile bumpers and foldable devices that facilitate their transportation.

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