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Abstract Cross‐species communication, where signals are sent by one species and perceived by others, is one of the most intriguing types of communication that functionally links different species to form complex ecological networks. Global change and human activity can affect communication by increasing fluctuations in species composition and phenology, altering signal profiles and intensity, and introducing noise. So far, most studies on cross‐species communication have focused on a few specific species isolated from ecological communities. Scaling up investigations of cross‐species communication to the community level is currently hampered by a lack of conceptual and practical methodologies. Here, we propose an interdisciplinary framework based on information theory to investigate mechanisms shaping cross‐species communication at the community level. We use plants and insects, the cornerstones of most ecosystems, as a showcase and focus on chemical communication as the key communication channel. We first introduce some basic concepts of information theory, then we illustrate information patterns in plant–insect chemical communication, followed by a further exploration of how to integrate information theory into ecological and evolutionary processes to form testable mechanistic hypotheses. We conclude by highlighting the importance of community‐level information as a means to better understand the maintenance and workings of ecological systems, especially during rapid global change. 

Abstract We have used kymograph analysis combined with edge detection and an automated computational algorithm to analyze the axonal transport kinetics of neurofilament polymers in cultured neurons at 30 ms temporal resolution. We generated 301 kymographs from 136 movies and analyzed 726 filaments ranging from 0.6 to 42 µm in length, representing ∼37,000 distinct moving and pausing events. We found that the movement is even more intermittent than previously reported and that the filaments undergo frequent, often transient, reversals which suggest that they can engage simultaneously with both anterograde and retrograde motors. Average anterograde and retrograde bout velocities (0.9 and 1.2 µm s⁻¹, respectively) were faster than previously reported, with maximum sustained bout velocities of up to 6.6 and 7.8 µm s⁻¹, respectively. Average run lengths (∼1.1 µm) and run times (∼1.4 s) were in the range reported for molecular motor processivity in vitro, suggesting that the runs could represent the individual processive bouts of the neurofilament motors. Notably, we found no decrease in run velocity, run length or run time with increasing filament length, which suggests that either the drag on the moving filaments is negligible or that longer filaments recruit more motors. 

Abstract In recent years, there have been rapid advances in the synthesis of lead halide perovskite nanocrystals (NCs) for use in solar cells, light emitting diodes, lasers, and photodetectors. These compounds have a set of intriguing optical, excitonic, and charge transport properties, including outstanding photoluminescence quantum yield (PLQY) and tunable optical band gap. However, the necessary inclusion of lead, a toxic element, raises a critical concern for future commercial development. To address the toxicity issue, intense recent research effort has been devoted to developing lead‐free halide perovskite (LFHP) NCs. In this Review, we present a comprehensive overview of currently explored LFHP NCs with an emphasis on their crystal structures, synthesis, optical properties, and environmental stabilities (e.g., UV, heat, and moisture resistance). In addition, strategies for enhancing optical properties and stabilities of LFHP NCs as well as the state‐of‐the‐art applications are discussed. With the perspective of their properties and current challenges, we provide an outlook for future directions in this rapidly evolving field to achieve high‐quality LFHP NCs for a broader range of fundamental research and practical applications. 

Abstract Despite recent progress in producing perovskite nanowires (NWs) for optoelectronics, it remains challenging to solution‐print an array of NWs with precisely controlled position and orientation. Herein, we report a robust capillary‐assisted solution printing (CASP) strategy to rapidly access aligned and highly crystalline perovskite NW arrays. The key to the CASP approach lies in the integration of capillary‐directed assembly through periodic nanochannels and solution printing through the programmably moving substrate to rapidly guide the deposition of perovskite NWs. The growth kinetics of perovskite NWs was closely examined by in situ optical microscopy. Intriguingly, the as‐printed perovskite NWs array exhibit excellent optical and optoelectronic properties and can be conveniently implemented for the scalable fabrication of photodetectors. 

Abstract Despite recent progress in producing perovskite nanowires (NWs) for optoelectronics, it remains challenging to solution‐print an array of NWs with precisely controlled position and orientation. Herein, we report a robust capillary‐assisted solution printing (CASP) strategy to rapidly access aligned and highly crystalline perovskite NW arrays. The key to the CASP approach lies in the integration of capillary‐directed assembly through periodic nanochannels and solution printing through the programmably moving substrate to rapidly guide the deposition of perovskite NWs. The growth kinetics of perovskite NWs was closely examined by in situ optical microscopy. Intriguingly, the as‐printed perovskite NWs array exhibit excellent optical and optoelectronic properties and can be conveniently implemented for the scalable fabrication of photodetectors. 

Abstract Thermoresponsive nanoparticles (NPs) represent an important hybrid material comprising functional NPs with temperature‐sensitive polymer ligands. Strikingly, significant discrepancies in optical and catalytic properties of thermoresponsive noble‐metal NPs have been reported, and have yet to be unraveled. Reported herein is the crafting of Au NPs, intimately and permanently ligated by thermoresponsive poly(N‐isopropylacrylamide) (PNIPAM), in situ using a starlike block copolymer nanoreactor as model system to resolve the paradox noted above. As temperature rises, plasmonic absorption of PNIPAM‐capped Au NPs red‐shifts with increased intensity in the absence of free linear PNIPAM, whereas a greater red‐shift with decreased intensity occurs in the presence of deliberately introduced linear PNIPAM. Remarkably, the absence or addition of free linear PNIPAM also accounts for non‐monotonic or switchable on/off catalytic performance, respectively, of PNIPAM‐capped Au NPs.