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Rapid and deliberate patterning of nanomaterials over a large area is desirable for device manufacturing. We report a method for meniscus‐assisted self‐assembly (MASA)‐enabled rapid positioning of hierarchically assembled dots and stripes composed of luminescent conjugated polymer over two length scales. Periodically arranged conjugated poly(9,9‐dioctylfluorene) (PFO) polymers, yield dots, punch‐holes and stripes at microscopic scale via MASA. Concurrent self‐assembly of PFOs into two‐dimensional lenticular crystals within each dot, punch‐hole and stripe is realized at nanoscopic scale. Hierarchical assembly is achieved by constraining the evaporation of the PFOs solution in two approximately parallel plates via a MASA process. The three‐phase contact line (TCL) of the liquid meniscus of the PFOs was printed using the upper plate, yielding an array of curved stripes. Rapid creation of hierarchical assemblies via MASA opens up possibilities for large‐scale organization of a wide range of soft matters and nanomaterials.

Rapid and deliberate patterning of nanomaterials over a large area is desirable for device manufacturing. We report a method for meniscus‐assisted self‐assembly (MASA)‐enabled rapid positioning of hierarchically assembled dots and stripes composed of luminescent conjugated polymer over two length scales. Periodically arranged conjugated poly(9,9‐dioctylfluorene) (PFO) polymers, yield dots, punch‐holes and stripes at microscopic scale via MASA. Concurrent self‐assembly of PFOs into two‐dimensional lenticular crystals within each dot, punch‐hole and stripe is realized at nanoscopic scale. Hierarchical assembly is achieved by constraining the evaporation of the PFOs solution in two approximately parallel plates via a MASA process. The three‐phase contact line (TCL) of the liquid meniscus of the PFOs was printed using the upper plate, yielding an array of curved stripes. Rapid creation of hierarchical assemblies via MASA opens up possibilities for large‐scale organization of a wide range of soft matters and nanomaterials.

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.

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.

In den letzten Jahren gab es rasante Fortschritte bei der Synthese von Bleihalogenid‐Perowskit‐Nanokristallen (NCs) für den Einsatz in Solarzellen, Leuchtdioden, Lasern und Photodetektoren. Sie besitzen eine Reihe faszinierender optischer, excitonischer und Ladungstransporteigenschaften, einschließlich hervorragender Photolumineszenz‐Quantenausbeuten (PLQY) und abstimmbaren optischen Bandlücken. Die notwendige Verwendung von Blei, einem toxischen Element, gibt jedoch Anlass zu ernsthafter Besorgnis über die zukünftige kommerzielle Entwicklung. Um das Problem der Toxizität zu lösen, wurden in jüngster Zeit intensive Forschungsarbeiten zur Entwicklung bleifreier Halogenid‐Perowskit(LFHP)‐NCs durchgeführt. In diesem Aufsatz geben wir einen Überblick über die derzeit erforschten LFHP‐NCs mit den Schwerpunkten Kristallstruktur, Synthese, optische Eigenschaften und Umgebungsstabilität (z. B. UV‐, Wärme‐ und Feuchtigkeitsbeständigkeit). Darüber hinaus werden Strategien zur Verbesserung der optischen Eigenschaften und Stabilitäten von LFHP‐NCs sowie deren neueste Anwendungen diskutiert.

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.

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.

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.