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Aqueous phase room‐temperature phosphorescence (RTP) materials are attracting increasing interest owing to their unique optical properties and promising applications. However, the realization of ultralong aqueous state RTP remains a formidable challenge due to severe quenching of triplet excitons in aqueous medium. In this study, a universal strategy is presented to achieve aqueous RTP materials through the encapsulation of organic phosphors within rigid hydrogen‐bonded organic frameworks (HOFs) by in situ self‐assembly. Benefiting from the compact and rigid microenvironments provided by HOFs, the nonradiative dissipations are immensely suppressed and populated triplet excitons are greatly stabilized by geometrical confinement and isolating organic phosphors from quenchers. As a result, the assembled HOFs‐based materials reveal robust RTP emission with an ultralong phosphorescence lifetime of up to 493.1 ms and exhibit long‐term optical and structural stability in water and even in harsh conditions (acid and base) for more than 10 days. Moreover, a fluorescent dye is introduced to finely tune the afterglow performance based on triplet‐to‐singlet Förster resonance energy transfer (TS‐FRET), facilitating advanced information encryption and anticounterfeiting applications. This study provides a reliable and universal method to design and prepare robust RTP materials and expands their applications in advanced information encryption. [ABSTRACT FROM AUTHOR]

Information leakage and counterfeiting are serious worldwide issues that tremendously impact legitimate businesses and human life. Inspired by the Noctiluca scintillans, a new fluorescence‐afterglow dual‐modal information encryption enabled by precisely coordination‐modulated ultralong organic phosphorescence (UOP) is presented. Strikingly, the optical properties including fluorescence, lifetime and intensity of UOP can be precisely modulated on‐demand through energy transfer by lanthanide (LnIII) coordination, which enables information camouflage by similar LnIII luminescence to provide misleading information along with data decryption in the form of mutual afterglow. Moreover, the important data can be encrypted in a spatial‐time‐resolved way by programmatically coding information with afterglow gradients, yielding greatly improved security for verifying the authenticity. This study provides a new avenue to precisely modulate the optical properties of UOP materials and broadens the scope of optical materials for innovative information encryption and anticounterfeiting applications. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Smart fluorescent patterns enable dynamic color variation under external stimuli, showing a much higher security level in the field of anti‐counterfeiting. However, there is still lacking of a simple and convenient way to achieve dynamic fluorescence changes. Herein, a fluorescent organohydrogel made up of a poly(N,N‐dimethylacrylamide‐co‐isopropylacrylamide) (p(DMA‐NIPAM)) hydrogel network and a poly(lauryl methacrylate) (PLMA) organogel network was fabricated via a two‐step interpenetrating technique. The former network bears naphthalimide moieties (DEAN, green fluorescent monomer) and the later contains 6‐acrylamidopicolinic acid (6APA, fluorescent ligand), leading to emitting green fluorescence. When Eu3+ was introduced and coordinated with 6APA, the organohydrogel displays red fluorescence, which can further emit yellow after applying thermal stimulus. Furthermore, by adjusting the proportion of comonomers, various organohydrogels can be obtained, which can be programmed and act as an effective platform for the encryption and decryption of secret information. [ABSTRACT FROM AUTHOR]

Some living organisms such as the octopus have fantastic abilities to simultaneously swim away and alter body color/morphology for disguise and self‐protection, especially when there is a threat perception. However, it is still quite challenging to construct artificial soft actuators with octopus‐like synergistic shape/color change and directional locomotion behaviors, but such systems could enhance the functions of soft robotics dramatically. Herein, we proposed to utilize unique hydrophobic carbon dots (CDs) with rotatable surficial groups to construct the aggregation‐induced emission (AIE) active glycol CDs polymer gel, which could be further employed to be interfacially bonded to an elastomer to produce anisotropic bilayer soft actuator. When putting the actuator on a water surface, glycol spontaneously diffused out from the gel layer to allow water intake, resulting in a color change from a blue dispersion fluorescence to red AIE and a shape deformation, as well as a large surface tension gradient that can promote its autonomous locomotion. Based on these findings, artificial soft swimming robots with octopus‐like synergistic shape/color change and directional swimming motion were demonstrated. This study provides an elegant strategy to develop advanced multi‐functional bio‐inspired intelligent soft robotics. [ABSTRACT FROM AUTHOR]

The high‐level semantic information extracted from the pedestrian attribute feature is an important element for pedestrian recognition. Pedestrian attribute recognition plays an important role in both intelligent video surveillance and pedestrian re‐identification promoting the convenience of searching and performance of model. This paper tries finding a practical method to improve the performance of the pedestrian re‐identification by combining pedestrian attributes and identities. The multi‐task learning method combines pedestrian recognition and attribute information in a direct way that considers the correlation between pedestrian attributes and identities but ignores the principle and degree of such correlation. To solve this problem, a new pedestrian recognition framework based on attribute mining and reasoning is proposed in this paper. To enhance the expression ability of attribute features, it designs spatial channel attention module (SCAM) based on attention mechanism to extract features from every attribute. SCAM can not only locate the attributes on the feature map, but also effectively mine channel features with a higher degree of association with attributes. In addition, both spatial attention model and channel attention model are integrated by multiple groups of parallel branches, which further improve the network performance. Finally, using the semantic reasoning and information transmission function of graph convolutional network, the relationship between attribute features and pedestrian features can be mined. Besides, pedestrian features with stronger expression ability can also be obtained. Experiment work is conducted in two databases, DukeMTMC‐reID and Market‐1501, which are commonly used in pedestrian recognition tasks. On the Market‐1501 dataset, the final effect of the algorithm model CMC‐1 can reach 94.74%, and mAP can reach 87.02%; on the DukeMTMC‐reID dataset, CMC‐1 can reach 87.03%, and mAP can reach 77.11%. The results show that our method is at the top of the existing pedestrian recognition methods. [ABSTRACT FROM AUTHOR]

Through continuous efforts in developing a new class of foldamers, homogeneous sulfono‐γ‐AApeptides have been designed and synthesized using tetraphenylethylene (TPE) moieties attached to the backbone as luminogenic sidechains. Based on previous crystal structures, it is found that these foldamers adopted a left‐handed 414‐helix. Due to the constraint of the helical scaffold, the rotation of the TPE moieties is restricted, leading to fluorescent emissive properties with high quantum yields not only at the aggregate state but also in solution. Investigation of the relationship between the structure and fluorescence behavior reveals that emission is induced by the combined effect of the aggregation‐induced emission and the rotated restriction from the backbone. Furthermore, as the packing mode of the luminogens can be precisely adjusted by the helical backbone, these foldamers are found to be circularly polarizable with relatively large luminescence dissymmetry factor. Interestingly, possessing cationic amphipathic structures similar to that of host‐defense peptides, these sulfono‐γ‐AApeptides are able to inhibit the growth of Gram‐positive bacteria, methicillin‐resistant Staphylococcus aureus through membrane interactions. [ABSTRACT FROM AUTHOR]

Summary of main observation and conclusion: Photoswitchable or photoactivatable fluorescent species have been found wide applications within supramolecular chemistry and materials science. In this study, we successfully constructed two highly emissive Pt(II) metallacycles from the diarylethene ligands via coordination‐driven self‐assembly. Different from the most known fluorescent metallacycles, the obtained metallacycles have displayed "turn‐on" fluorescence switching. They are non‐fluorescent in solution, but they emit highly yellow or orange fluorescence under ultraviolet irradiation. The metallacycles were well characterized by 1H NMR, 31P NMR and ESI‐TOF‐MS. The photochromic properties of the resultant metallacycles were investigated by 1H NMR, 31P NMR, UV/Vis spectrum and fluorescence spectrum. Notably, NMR studies revealed that these two metallacycles featured excellent cyclization efficiency (90% conversion efficiency). Moreover, the closed‐ring isomers of the metallacycles displayed relatively high quantum yield (ΦF = 0.5). DFT simulations demonstrated that the antiparallel configuration of the diarylethene ligand had an angle closed to 120°, which was more stable in energy compared to the parallel configuration, thus allowing for the facile construction of highly emissive metallacycles. We believe that such highly emissive metallacycles which are in‐situ prepared upon irradiation can be used as new fluorescence materials for sensing and bioimaging in the future. Upon UV irradiation, the metallacycles can transform from the open‐ring isomers to their closed‐ring isomers. Moreover, the closed‐ring isomers featured a relatively high fluorescence quantum yield. This property of "turn‐on" fluorescence switching will be very helpful in construction of new supramolecular fluorescent materials for sensing and bioimaging. [ABSTRACT FROM AUTHOR]

Self‐assembly post‐modification has proven to be an efficient strategy to build higher‐order supramolecular architectures and functional materials. In this study, we successfully realized the construction of a new family of neutral supramolecular polymeric films containing well‐defined metallacycles as the main scaffolds through combination of coordination‐driven self‐assembly with post‐electropolymerization. The obtained neutral polymeric materials were fully characterized by the cyclic voltammogram (CV), SEM, and TEM. The thickness of the films was able to be well regulated by the number of scanning cycles. Moreover, we found that the shape of the metallacycles and the number of triphenylamine moieties played important roles in the formation of the final polymer films. We believe that the introduction of the neutral metallacycles into the final polymer structures not only enriches the library of supramolecular polymeric films but also provides a new platform to study neutral molecule detection, separation, and capture. [ABSTRACT FROM AUTHOR]

Pollution caused by heavy metal ions has become a global issue owing to their severe threat to the ecological environment and human health. However, it remains a considerable challenge to detect heavy metal ions in an efficient, selective, and high signal‐to‐noise ratio way. Herein, a portable and sensitive method is presented to probe Hg2+ by using an ultralong afterglow dispersion. The in situ encapsulation of phosphorescent carbon dots (CDs) within rigid hydrogen‐bonded organic frameworks (HOFs) leads to ultralong room temperature phosphorescence (RTP) in water with a maximum lifetime of up to 974.86 ms. Moreover, the resultant CDs@HOFs material exhibits robust and long‐term RTP emission with enhanced performance under strongly acidic or alkaline conditions, which contributes to the practical detection of Hg2+ in water. As such, an efficient and sensitive afterglow probe is facilely fabricated by integrating CDs@HOFs with a Hg2+ probe Rhodamine B derivative (RhBTh), demonstrating selective sensing of Hg2+ with greatly improved signal‐to‐noise ratios based on the triplet‐singlet Förster resonance energy transfer system (TS‐FRET). This work not only provides a reliable and versatile method for realizing robust RTP emission in water, but also expands the applications of afterglow materials in the field of optical sensing of toxic analytes. [ABSTRACT FROM AUTHOR]

The inside cover picture shows in situ construction of highly emissive Pt(II) metallacycles upon irradiation. The self‐assembled diarylethene‐containing metallacycles can realize supramolecular transform from the open‐ring isomers to their closed‐ring ones under UV irradiation. Moreover, the closed‐ring isomers featured a relatively high fluorescence quantum yield. This property of "turn‐on" fluorescence switching provides a new method to construct highly emissive supramolecular fluorescent materials by light stimulus. More details are discussed in the article by Yang et al. on page 323–329. [ABSTRACT FROM AUTHOR]

The inside back cover picture shows the construction of neutral supramolecular polymeric films containing well‐defined metallacycles as the main scaffolds through combination of coordination‐driven self‐assembly with post‐electropolymerization. A new 120° triphenylamine substituted dicarboxylate donor ligand and the complementary 120° triphenylamine functionalized di‐Pt(II) acceptor were employed to build neutral multi‐triphenylamine functionalized 2‐D metallacycles with the well‐defined shape and size via the formation of oxygen‐to‐platinum coordination bonds. Subsequent post‐electropolymerization of the obtained neutral multi‐triphenylamine containing metallacycles allowed for fabrication of a new type of neutral polymeric film with well‐controlled cavity sizes and thickness, which may have potential applications in neutral molecule detection, separation, and capture. More details are discussed in the article by Yang et al. on page 134–138. [ABSTRACT FROM AUTHOR]