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Manipulating the molecular aggregation and crystallization behavior of polymer acceptors (PAs) is one of the most important challenges for all-polymer solar cells (all-PSCs). In this work, we combine the advantages of a random ternary copolymerization strategy and fused perylene diimide dimer (FPDI) to synthesize a series of random copolymers (PNDI-FPDIX) for tuning and optimizing the self-aggregation of a prototypical PA (N2200). Specifically, FPDI with a quasi-two-dimensional structure was used as the guest acceptor unit to modify N2200 by substituting a certain amount of naphthalene diimide (NDI) acceptor unit, which not only regulates the optoelectronic properties but also alters the film morphology of the resultant random copolymers. The prepared PTzBi:PNDI-FPDI10 blend with 10% of the NDI monomers replaced by FPDI resulted in an excellent power conversion efficiency of 8.21% with an open-circuit voltage of 0.84 V, a short circuit current density of 14.81 mA cm−2, and a fill factor of 66.03%. This work demonstrates that the aggregation behavior of PAs and thus efficiency of all-PSCs can be controlled by rationally selecting the guest component to construct random copolymers. [ABSTRACT FROM AUTHOR]

Flexible hydrogel film sensors have great advantages as human–machine interfaces for conformal contact with bio‐tissues, but suffer from weakness and dehydration, compromising flexibility and performance. Here, a breathable, highly stretchable, and anti‐dehydrating ultrathin organohydrogel film as a skin‐attachable strain sensor for long‐term motion monitoring is developed. An electrospun TPU (eTPU) nanomesh with hidden strength is used as skeleton to host in situ free radical polymerization of 2‐acrylamido‐2‐methyl propane sulfonic acid (AMPS) and acrylamide (AAm) to form an interpenetrating double network organohydrogel with glycerol and water as solvent. Extensive hydrogen bonding between eTPU nanomesh and P(AMPS‐co‐AAm) network yields ultrathin organohydrogel film (≈200 µm) with synergetic deformation and energy dissipation upon stretching, leading to record‐high stretchability up to 920%, fracture toughness of 20.14 MJ m−3, fracture energy of 10 000 J m−2, and robustness over 4000 notched stretching cylcles to 50% strain. The binary glycerol/water solvent imparts excellent anti‐dehydration at room temperature for 10 d, and stable sensory performance from −20 to 60 °C. With a high water vapor transmission rate of 1.3 kg m−2 d−1, the film sensor ensures comfortable skin contact for continuous knee flexion monitoring throughout the day with stable signals. These organohydrogel film strain sensors are promising for wearable and long‐term motion monitoring applications. [ABSTRACT FROM AUTHOR]

Leptochloa chinensis is a troublesome rice weed in many countries, and knowledge of its seed germination ecology varied in different reports. To reveal the range and general characteristics of L. chinensis seed germination under different drought stresses, and seedling emergence under different burial depths, we conducted a serial of germination experiments with 242 L. chinensis populations collected along ranges spanning 4° latitudes and 4° longitudes from rice fields in eastern China. We found that 1000‐seed weight ranged from 0.056 to 0.129 g, with an average of 0.088 g; the OR50 (the osmotic potentials at which the germination percentage reaches 50%) was −0.47 to −0.07 MPa, with an average of −0.28 MPa; and BR50 (the burial depth at which the emergence percentage reaches 50%) ranged from 0.07 to 0.26 cm, with an average of 0.18 cm. At −0.5 MPa, the mean germination percentage of 242 populations was 4.1%. Seed germination percentages under 0.5 and 1.5 cm quartz sand layer were both >75%, while no seedling emerged up to the surface of quartz sand. Populations collected from rice fields in northern regions leaned to be higher in 1000‐seed weights, and OR50 values. Moreover, populations collected from transplanting rice fields slightly and significantly leaned to be more adapted to drought stresses and soil burial depths. The ability to quickly germinate, together with seed germination sensitive to drought stress and seedling emergence sensitive to soil burial, facilitate L. chinensis to avoid suicide seed germination, occupy niches under suitable environments and escape chemical control practices on rice fields. [ABSTRACT FROM AUTHOR]

Flow control devices have garnered significant attention from domestic and international wind energy scholars. In an effort to capture more wind energy and boost the output power of wind turbines, this study incorporates flow control devices into the upstream area of the wind turbine. The study then assesses the impact of the spacing, tilt angle, and height of the flow control devices on the turbine's performance. The study demonstrates that the addition of flow control devices does lead to a notable enhancement in wind turbine power, with a maximum power output growth rate of 9.74%. The maximum growth rates for the average output power of the wind turbine due to the three factors (α, H, and Lw) are 4.20%, 3.76%, and 3.54%, respectively. The degree of influence of the three factors is as follows: α > H > Lw. [ABSTRACT FROM AUTHOR]

Site and climate conditions are the key determinants controlling dominant height growth and forest productivity, both independently and interactively. Secondary natural oak forests are a typical forest type in China, especially in Hunan Province, but little is known about the site index of this forest under the complex site and climate variables in the subtropics. Based on survey data of dominant trees and site variables from 101 plots in Hunan oak natural secondary forests and climate data obtained using spatial interpolation, we used the random forest method, correlation analysis, and the analysis of variance to determine the main site and climate factors affecting oak forest dominant height and proposed a modeling method of an oak natural secondary forest site index based on the random effect of site–climate interaction type. Of the site variables, elevation affected stand dominant height the most, followed by slope direction and position. Winter precipitation and summer mean maximum temperature had the greatest impact on stand dominant height. To develop the modeling method, we created 10 popular base models but found low performance (R2 ranged from 0.1731 to 0.2030). The optimal base model was Mitscherlich form M3 (R2 = 0.1940) based on parameter significance tests. Since site and climate factors affect the site index curve, the dominant site and climate factors were combined into site types and climate types, respectively, and a nonlinear mixed-effects approach was used to simulate different site types, climate types, site–climate interaction types, and their combinations as random effects. Site–climate interaction type as a random factor enhanced model (M3.4) performance and prediction accuracy (R2 from 0.1940 to 0.8220) compared to the optimum base model. After clustering the 62 site–climate interaction types into three, five, and eight groups using hierarchical clustering, a mixed-effects model with the random effects of eight groups improved model performance (R2 = 0.8265) and applicability. The modeling method developed in this study could be used to assess a regional secondary natural oak forest site index under complex site and climate variables to evaluate the forest productivity. [ABSTRACT FROM AUTHOR]

Simple Summary: Plant invasion represents a significant global ecological challenge, and effective management of invasive species requires robust weed risk assessment systems. These systems predominantly rely on understanding the relationships between life history traits and weed occurrence. In this study, we conducted a survey of native weed communities across 666 field sites in agricultural areas of Yangzhou City, China, covering a longitudinal range of 0.86°, a latitudinal range of 0.84°, and an altitude below 100 m. Our findings reveal that dominant weed species are concentrated within a few families and are associated with higher levels of weediness globally. The key traits of prevalent native weeds include moderate plant height, absence of thorns, non-succulent, erect growth forms or lianas, and adaptability to a range of light conditions, whether mesophytic or xerophytic. Dominant native weeds were frequently annuals, biennials, or perennials with moderate vegetative reproduction abilities and high fertility, possessing seeds of moderate size and fruits without mucilage, conspicuous hairs, thorns, or awns. Additionally, many have developed herbicide resistance. This study is the first to focus on the diversity and life history traits of native weed communities in China, providing valuable insights for refining weed risk assessment and management strategies. Native weeds have a long history of adaptation to local environments. Understanding the relationship between the occurrence of native weeds and their life history traits is crucial for effective weed management and risk assessment of plant invasions. In this study, we surveyed native weed species and their dominance across 666 field sites in agricultural areas of Yangzhou City, China, and each site was 13.3 hectares in area. A total of 287 native weed species were recorded, referring to 63 families, among which 45% were 50–100 cm in plant height and 47% were of an erect life type. In terms of the proportions out of the total native weed occurrence dominance, Poaceae, Compositae, and Fabaceae weeds accounted for 30%, 13%, and 11%; liana and perennials both occupied 32%; and aquatic, hygrophyte, sun plant, and shade plant all occupied < 10%. Additionally, the proportions increased with increasing seed production per plant and with increasing weediness reported worldwide. Native weed groups holding moderate vegetative reproduction abilities, moderate seed sizes, or herbicide resistance showed higher proportions. Moreover, most of the native weeds surveyed were not succulent or thorny plants and did not hold thorns, awns, obvious hairs, or mucilage on their fruits. [ABSTRACT FROM AUTHOR]

Leptochloa chinensis (L.) Nees is a troublesome rice weed. We collected 242 L. chinensis populations from rice fields in eastern China and studied the duration of seed dormancy and the seed germination ability at different temperatures. All L. chinensis populations studied exhibited seed dormancy. The periods required to reach 50% germination under optimal conditions were 31–235 days, with an average of 96 days. None of the populations germinated at 15 °C. Under constant temperatures of 20, 25, 30, and 35 °C, the average germination percentages of 242 populations were 0%, 71%, 79%, and 60% at 2 days after treatment (DAT), and were 56%, 84%, 88%, and 88% at 14 DAT, respectively. The duration of seed dormancy, as well as the germination ability of seeds, were significantly (p < 0.05) influenced by the agricultural region and the longitude and latitude of the collection locations. Under constant temperatures of 20 to 35 °C, the average germination percentages of seeds collected from transplanted rice fields were significantly higher than those collected from direct-seeded fields. This is the first study on seed germination biology of L. chinensis with multiple populations systematically collected from rice fields on a regional scale. [ABSTRACT FROM AUTHOR]

The clinical treatment of chronic diabetic wounds is a long-standing thorny issue. Strategies targeting the diabetic micro-environment have been developed to promote wound healing. However, it remains challenging to reverse the adverse conditions and re-activate tissue regeneration and angiogenesis. In this work, we develop injectable hydrogels that are responsive to acidic conditions, reactive oxygen species (ROS), and high glucose levels in a diabetic wound micro-environment to sustainably deliver tannic acid (TA) to augment antibacterial, anti-inflammatory, and anti-oxidative activities. This triple-responsive mechanism is designed by introducing dynamic acylhydrazone and phenylboronic ester bonds to crosslink modified hyaluronic acid (HA) chains. At a diabetic wound, the acylhydrazone bonds may be hydrolyzed at low pH. Meanwhile, glucose may compete with TA, and ROS may oxidize the C–B bond to release TA. Thus, sustained release of TA is triggered by the diabetic micro-environment. The released TA effectively scavenges ROS and kills bacteria. In vivo experiments on diabetic mice demonstrate that the hydrogel dressing highly promotes angiogenesis and extracellular matrix (ECM) deposition, leading to eventual full healing of diabetic skin wounds. This micro-environment-triggered triple-responsive drug release provides a promising method for chronic diabetic wound healing. [ABSTRACT FROM AUTHOR]

Thermochromic energy efficient windows dynamically regulate building energy exchange by changing their optical transmittance. Recently, thermochromic materials with different chromic mechanisms are developed to fulfill smart window demands. Advanced fabrication technologies for smart windows also lead to building energy efficiency optimization. In this Perspective, representative mechanisms and performances of promising thermochromic systems, including vanadium dioxide, hydrogels, perovskites, ionic liquids, and liquid crystals, are discussed. Furthermore, the emerging technology of radiative cooling is emphasized for future building energy saving. Building temperature regulation and energy saving based on smart windows will make great impacts on the global low carbon economy. [ABSTRACT FROM AUTHOR]