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Ultrafiltration (UF) membranes with excellent dye removal and antibacterial activity are highly desired in dye wastewater treatment, and more importantly environmental protection puts high demands on polymeric membrane materials. In this work, three methacrylate copolymers containing quaternary ammonium salt were synthesized to cast UF membranes. The physicochemical property, structural evolution, dye separation, and antibacterial activity of as‐prepared membranes were systematically investigated. With increased content of the hydrophilic monomer allyl polypropylene glycol (APPG) in the feed, the wettability and positive charge of the resultant membranes were enhanced. Remarkably, the supporting layer of membranes changed from finger‐like pore structure to sponge‐like pore structure by increasing APPG content, and the sponge‐like membranes showed higher retention rates for dyes (99.78% for victoria blue B, 90.49% for methylene blue, and 97.43% for methyl blue) compared with the finger‐like membranes. Besides, the sponge‐like membranes exhibited high rejection for vctoria blue B (>99%) in dye/salt mixture and simultaneously low rejection for salts (<10%), indicating effective selective separation to dye/salt mixture, and also achieved easy regeneration. It was also found that increased hydrophilicity and positive charge endowed membranes with better antibacterial activity. This work will provide an alternative for dye/salt selective separation in dye effluent treatment. [ABSTRACT FROM AUTHOR]

Organic red/near‐infrared (NIR) room temperature phosphorescence (RTP) materials with low toxicity and facile synthesis are highly sought after, particularly for applications in biotechnology and encryption. However, achieving efficient red/NIR RTP emitters has been challenging due to the weak spin‐orbit coupling of organics and the rapid nonradiative decay imposed by the energy gap law. Here we demonstrate highly efficient red/NIR RTP with boosted quantum yields (Φps) of up to 32.96 % through doping the thionated derivatives of phthalimide (PAI) (MTPAI and DTPAI) into PAI crystals. The red‐shifted photoluminescence (PL) stems from a combination of the external heavy atom effect and the formation of emissive clusters centered around electron‐rich sulfur atoms. Furthermore, the dopants enhance exciton generation efficiency and facilitate energy transfer from smaller PAI units to larger aggregates, leading to dramatically increased Φp. This strategy proves universal, opening possibilities for acquiring long‐wavelength RTP with tunable photophysical properties. The doped crystals exhibit promising applications in optical waveguides and encryption paper/ink. This research provides a practical approach to obtaining long‐wavelength RTP materials and offers valuable insights into the mechanisms governing host‐guest systems. [ABSTRACT FROM AUTHOR]

Polarization‐sensitive photodetection has intensive practical applications, including optical anti‐counterfeiting, image encryption, and remote sensing. 2D hybrid perovskites have emerged as a robust candidate in this portfolio, due to their inherent quantum‐confined structure and anisotropic properties. However, studies on the chemical assembly of inorganic‐layer thickness to regulate structural anisotropy and polarization‐sensitive photodetection behavior remain insufficient. Here, the inorganic‐layer thickness of 2D homologous perovskites is regulated, (MBA)2(CH3NH3)n−1PbnI3n+1 (n = 1–3, where MBA = 4‐methylbenzylamine), featuring the similar polar structures and strong optical anisotropy. Notably, photoelectric merits are greatly improved from n = 1 to n = 3 with the weakening of the quantum confinement effect. Under illumination, the n = 3 member exhibits large on/off ratios of photocurrent (≈2.1 × 104) far beyond other lower‐layered counterparts. The polarized‐light photodetector based on n = 3 crystal shows intriguing behaviors, including noticeable responsivity (1.2 mA W−1), detectivity (9.5 × 1013 Jones), and superior photocurrent anisotropy (≈110.4). Besides, fascinating self‐powered polarization behaviors with a large anisotropy contrast are achieved based on the bulk photovoltaic effect, stemming from the structural polarity. These characteristics underscore the design strategy of inorganic‐layer regulation in advancing the exploration of new 2D perovskite candidates for polarization‐based optoelectronics. [ABSTRACT FROM AUTHOR]

Aliphatic quaternary ammonium salts (QASs) with intrinsic photoluminescence (PL) have drawn increasing attention due to the importance of exploring the mechanism of ionic emissive clusters, whereas it remains challenging to clarify structure–property relationships. Here, the effective modulation of photophysical properties of gemini aliphatic QASs (n‐BTADB) is managed by altering the alkyl chain length. Boosted quantum yields (up to 24.6%), prolonged phosphorescence lifetimes (up to 515.2 ms), and varied PL colors are achieved by manipulating the aggregation states of the compounds. Interlaced herringbone packing patterns and strong ionic interactions facilitate the intersystem crossing process and stabilize the triplets. The confluence of varied hydrophobic interactions and chain flexibility results in the fluctuation of phosphorescence lifetimes as the alkyl chain lengthens. Furthermore, the single‐component white‐light emission is obtained in 12‐HBTADB crystals by introducing electron‐rich hydroxyls. These results shed new light on the structure–property relationships of ionic emissive clusters and the rational design of nonconventional ionic luminophores. [ABSTRACT FROM AUTHOR]

Al matrix composites (AMCs) are innovative materials prepared by introducing various reinforcements into Al alloys using suitable processes. Traditional particle‐reinforced AMCs usually have high strength but poor interfacial bonding, resulting in low plasticity. Researchers are attempting to solve this problem by identifying more proper reinforcing particles. High‐entropy alloys (HEAs) with excellent mechanical properties including high strength, ductility, and wear resistance are becoming attractive candidates for the reinforcement of Al alloys. The HEAs‐reinforced AMCs (HEAs@AMCs) combine the lightweight property of Al alloys and superior mechanical properties of HEAs. In this article, a comprehensive overview is provided on the HEAs@AMCs, starting with an introduction to the properties of HEAs, followed by the design principle of HEAs for the metal matrix composites. After that, the preparation, microstructure, and mechanical properties of the HEAs@AMCs are examined. In addition, the effects of HEAs on the microstructure and mechanical properties of the HEAs@AMCs are explored. [ABSTRACT FROM AUTHOR]

Amphiphilic cationic polymers mimicking the membrane‐disrupting mechanism of natural antimicrobial peptides displays high‐efficacy bactericidal activity and meanwhile good biocompatibility, while electrostatic adsorption enables bacteria to adhere to substrate surfaces, effectively lowering the antimicrobial effect, so it is worthwhile to tackle the problem of bacterial adhesion to prolong its antibacterial activity. Herein, a kind of polyquaternium latex (PQL) was synthesized to coat polypropylene nonwoven fabrics (PPNFs) with bacterial repellency and rapid biocidal activity toward both Staphylococcus aureus and Escherichia coli. Compared with polyquaternium solution coatings, latex coatings provided PPNFs with unique microscopic morphology and surface chemistry rich in polyoxyethylene moieties, achieving better resistance to bacterial adhesion, and meanwhile PQL coated PPNFs also delivered 99% killing rates against both bacteria within 2 min. After exposure to ultrasonic cleaning for 4 h, PQL modified PPNFs still demonstrated good bactericidal activity. Moreover, they also displayed low cytotoxicity. This work provides guidance for the design of antibacterial and antiadhesion coatings to combat bacterial infection. [ABSTRACT FROM AUTHOR]

This paper focuses on the intelligent detection of prohibited items in X‐ray images during the security checking process. An intelligent semantic segmentation model of prohibited items in X‐ray images is proposed based on the attention‐based object localization method. Based on the pre‐trained CNN classification framework, the attention mechanism can map the high‐layer semantic information of objects into the input space, while generating energy saliency maps to locate the prohibited items. In order to make the obtained attention maps discriminative, the lateral and contrastive inhibition strategies are introduced and combined together which can highlight the responses of activated neurons. Under the guidance of attention responses, two traditional image segmentation algorithms are employed to achieve the semantic segmentation results for the prohibited items detection in X‐ray images. The proposed semantic segmentation model relies on weakly supervised learning mechanism, and only depends on the category labels of prohibited items, which greatly avoids the work cost of data semantic annotation. The experimental results based on the public SIXray baseline and the self‐built X‐ray image database demonstrate the proposed method can achieve about 65% IoU localization precise averagely. In addition, comparison experiments were carried out with the state‐of‐the‐arts and ablation experiments to verify the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

As scaling down to the nanoscale, the dramatically increased morphological deviation between nanostructures becomes a major challenge in implementing large‐scale nanodevices. On the other side of the coin, the often‐undesirable rich non‐repeatable randomness introduced during nanostructure growth and subsequent device fabrication is of great value in the implementation of physically unclonable functions (PUF), a booming innovative security primitive. Herein, it is shown that the self‐oriented organic nanowires grown on a faceted surface through a vapor transport process are advanced building blocks for the implementation of two novel PUFs. An optical PUF is first demonstrated by exploiting the unclonable morphological randomness of the self‐oriented nanowires (e.g., length, thickness, density, and location), which can provide an entity‐specific primary encryption for nanowire devices. Next, these nanowires are integrated into photodetector arrays directly on their growth substrate and accordingly enable an electrical PUF based on the inherent resistance variation between detector cells. Furthermore, by combining these two PUFs, a secondary encryption with higher security is proposed for information communication. The implementation of nanowire‐based PUFs not only opens a new device direction to exploit the annoying unclonable randomness of bottom‐up nanowires, but also provides innovative label‐free security primitives for emerging nanowire‐based devices and systems. [ABSTRACT FROM AUTHOR]

Traditional approaches for monitoring human gait have severe spatial and temporal restrictions with complex analysis methods and high cost, which are powerless to promote the development of intelligent life involving fitness, sport training, and healthcare. Herein, a portable smart insole system with high spatial resolution and simple manufacturing process to measure plantar pressure distribution anytime, anywhere for gait analysis is proposed. An insole‐shaped array of 104 piezoresistive sensors with highly robust characteristics is assembled, exhibiting a good pressure‐sensing uniformity. The smart insole not only detects the subtle displacement of the center of gravity of the body, but also exhibits a real‐time, high‐resolution thermodynamic diagram of the plantar pressure distribution during human activities. More importantly, the function of motion intelligence identification can be realized by regionalizing and digitizing the whole plantar pressure distribution, achieving an average recognition accuracy of 83.32% among six predefined motions. These results imply that the carbon fiber‐based smart insole can provide an effective approach for convenient gait analysis and motion identification, which has a great potential in the application of future intelligent life. [ABSTRACT FROM AUTHOR]

Summary: An excitation voltage with a high rising rate, falling rate, and idle time simultaneously is beneficial to taking advantage of the potential of dielectric barrier discharge (DBD) loads. However, how to generate this kind of excitation voltage with a simple structure is rarely researched. To address the issue, a novel LC‐based bipolar high‐voltage pulsed power supply is proposed in this paper. The proposed power supply is comprised of an inductance, two capacitances, a step‐up transformer, and two power switches sharing the same ground. By planning the switch sequence of the two power switches, a resonant stage and an idle stage are formed. The resonant stage is used to generate a bipolar pulse excitation voltage on DBD excimer lamps and an idle time in the excitation voltage is generated in the idle stage. The characteristics and the parameters design of the proposed power supply are studied by theoretical analysis. To verify the feasibility of the proposed power supply, an experimental setup is built with a DBD‐type excimer lamp. The experimental results show that the power supply not only better takes advantage of the potential of DBD excimer lamps, but also there is a fine luminous regulation feature for the excimer lamp. Besides these characteristics, the proposed power supply has several other benefits, such as good adaptability to different DBD‐type excimer lamps, a small number of components, and high efficiency. [ABSTRACT FROM AUTHOR]

This study investigated the influence of water injection timing on the compression deformation of loose rock blocks in the goaf. The study used a confined gradient loading compression test to examine the deformation of loose rock blocks under initial saturation and later immersion conditions. The results showed that under initial saturation, the deformation of each loading gradient and the whole loading stage was greater than that of the later immersion stage. Additionally, the deformation of different stages in the initial saturated state was relatively regular, while in the later immersion state, the deformation changed abruptly after immersion. To explain the deformation mechanism of loose rock blocks, the mesostructure of loose rock blocks was granulated and the contact mechanism of particles was studied. The study found that water weakens the effective contact stress and strength between the skeleton particles, leading to sliding deformation as the dominant deformation mode. The study provides a theoretical basis for understanding the deformation characteristics of loose rock blocks in the goaf under different water environments. [ABSTRACT FROM AUTHOR]

Large‐scale on‐chip integration of organic nanowire‐based devices requires the deterministic assembly of organic small molecules into highly‐aligned nanowires. In this work, phthalocyanine molecules are self‐assembled into horizontally‐aligned nanowires after generating parallel hydrophobic nanogrooves on a sapphire surface. In contrast to previous self‐oriented inorganic nanowires, these molecular nanowires are separated from their supporting sapphire by an ultrathin amorphous layer, indicating a complete elimination of lattice matching between nanowires and substrates. Therefore, small molecules beyond phthalocyanines hold promise to form aligned nanowires using this graphoepitaxial self‐assembly strategy. The excellent alignment and high crystallinity of these nanowires enable the desired in‐situ integration of nanowire‐based devices without additional postgrowth processing steps. As a proof of concept, self‐oriented CuPc nanowires are integrated into photodetector arrays directly on their growth substrate after electrode arrays are transferred onto the nanowires. Compared to previous CuPc photodetectors constructed using other approaches, these detectors exhibit a faster response to the spectrum in the 488–780 nm range (rise and fall times are 0.05–0.43 s and 0.38–2.34 s, respectively) while offering comparable detectivities (2.49 × 1010 Jones on average). This graphoepitaxial self‐assembly offers new opportunities for the aligned growth of organic crystalline nanowires and their large‐scale in‐situ integration into functional devices. [ABSTRACT FROM AUTHOR]

Various epitaxial mechanisms have been proposed to control the growth orientation of vapor‐deposited nanowires, yet the required lattice matching between target nanowires and supporting substrates limits their applicability. In this work, a versatile hot stamping protocol for fabricating parallel hydrophobic nanogrooves on flexible polymer films (e.g., polyimide (PI), polyethylene naphthalate (PEN), polydimethylsiloxane (PDMS)) is proposed. More interestingly, various organic small molecules, including several metal phthalocyanines (MPc, M = Cu, Zn, Fe, Ni, Co), 9,10‐bis(phenylethynyl)anthracene (BPEA), 9,10‐diphenylanthracene (DPA), and tris‐(8‐hydroxyquinoline)aluminium (Alq3), are directly assembled into horizontally‐oriented nanowires along the hot‐stamped nanogrooves on a flexible PI film, thereby breaking the lattice‐matching limitation for oriented nanowire growth. These submillimeter‐long horizontally oriented nanowires can be integrated into flexible photodetectors directly on their growth film, eliminating the need for laborious post‐growth transfer and alignment steps and the associated structural damage and contamination. Consequently, the in situ integrated flexible photodetector made of aligned CuPc nanowires maintains a stable and fast photoresponse to a spectrum in the region of 405‐980 nm even when the detector is bent to a radius of curvature of 2.5 mm and 1000 times. This work will open new opportunities to develop in situ integrated flexible devices based on organic crystalline nanowires for practical applications. [ABSTRACT FROM AUTHOR]

Through crosstalk, FLAGELLIN SENSITIVE 2 (FLS2) and RESPIRATORY BURST OXIDASE HOMOLOG D (RBOHD) are involved in regulating the homeostasis of cellular reactive oxygen species (ROS) and are linked to the metabolic response of plants toward both biotic and abiotic stress. In the present study, we examined the metabolome of Arabidopsis seedlings under drought and salt conditions to better understand the potential role of FLS2 and RBOHD‐dependent signaling in the regulation of abiotic stress response. We identified common metabolites and genes that are regulated by FLS2 and RBOHD, and are involved in the response to drought and salt stress. Under drought conditions, D‐aspartic acid and the expression of associated genes, such as ASPARAGINE SYNTHASE 2 (ASN2), increased in both fls2 and robed/f double mutants. The accumulation of amino acids, carbohydrates, and hormones, such as L‐proline, D‐ribose, and indoleacetaldehyde increased in both fls2 and rbohd/f double mutants under salt conditions, as did the expression of related genes, such as PROLINE IMINOPEPTIDASE, PHOSPHORIBOSYL PYROPHOSPHATE SYNTHASE 5, and NITRILASE 3. Collectively, these results indicate that the FLS2‐RBOHD module regulates plant response to drought and salt stress through ROS signaling by adjusting the accumulation of metabolites and expression of genes related to metabolite synthesis. [ABSTRACT FROM AUTHOR]

Bioinspired asymmetric nanofluidic ion channels with ionic diode behavior that can boost the osmotic energy (so‐called blue energy) conversion are highly desirable, especially if they can be easily constructed and modified. Two‐dimensional (2D) metal carbides and nitrides, known as MXenes, combine hydrophilic surfaces and tunable surface charge properties, providing a shortcut to prepare asymmetric nanofluidic ion channels. Here, we report a mechanically robust, flexible, and scale‐up‐friendly asymmetric Ti3C2Tx MXene‐based ionic diode membrane with a highly rectified current and demonstrate its potential use in reverse electrodialysis osmotic energy conversion. Under the salinity gradient of synthetic seawater and river water, our ionic diode membrane‐based generator's power density is 8.6 W m−2 and up to 17.8 W m−2 at a 500‐fold salinity gradient, outperforming the state‐of‐the‐art membranes. The design of MXene‐based ionic diode‐type membrane provides a facile and general strategy in developing large‐scale 2D nanofluidics and selective ion transport. [ABSTRACT FROM AUTHOR]

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SUMMARY: The recent and continuous improvement in single‐cell RNA sequencing (scRNA‐seq) technology has led to its emergence as an efficient experimental approach in plant research. However, compared with single‐cell research in animals and humans, the application of scRNA‐seq in plant research is limited by several challenges, including cell separation, cell type annotation, cellular function analysis, and cell–cell communication networks. In addition, the unavailability of corresponding reliable and stable analysis methods and standards has resulted in the relative decentralization of plant single‐cell research. Considering these shortcomings, this review summarizes the research progress in plant leaf using scRNA‐seq. In addition, it describes the corresponding feasible analytical methods and associated difficulties and problems encountered in the current research. In the end, we provide a speculative overview of the development of plant single‐cell transcriptome research in the future. Significance Statement: The application of single‐cell RNA sequencing (scRNA‐seq) technology in plant research is limited by several challenges, although the continuous improvement has led to its emergence as an efficient experimental approach in plant research. Considering these shortcomings, this review summarizes the research progress and describes the corresponding feasible analytical methods in the current research. In the end, we provide a speculative overview of the development of plant single‐cell transcriptome research in the future. [ABSTRACT FROM AUTHOR]

An ion‐selective membrane can directly convert the osmotic energy to electricity through reverse electrodialysis. However, developing an advanced membrane that simultaneously possesses high power density, excellent mechanical strength, and convenient large‐scale production for practical osmotic energy conversion, remains challenging. Here, the fabrication of ultrathin and ultrastrong Kevlar aramid nanofiber (KANF) membranes with interconnected three‐dimensional (3D) nanofluidic channels via a simple blade coating method is reported. The negatively charged 3D nanochannels show typical surface‐charge‐governed nanofluidic ion transport and exhibit excellent cation selectivity. When applied to osmotic energy conversion, the power density of the KANF membrane‐based generator reaches 4.8 W m–2 (seawater/river water) and can be further increased to 13.8 W m–2 at 328 K, which are higher than most of the state‐of‐the‐art membranes. Importantly, a 4‐µm‐thickness KANF membrane shows ultrahigh tensile strength (565 MPa) and Young's modulus (25 GPa). This generator also exhibits ultralong stability over 120 days, showing great potential in practical energy conversions. [ABSTRACT FROM AUTHOR]

Based on the industry data and enterprise data from tens of thousands of small and medium-sized enterprises, a deep learning and machine learning model of credit prediction is constructed through the division of data sets, processing, and integration of models. At first, with the help of two characteristic selection methods, several subsets separated from the dataset are analyzed based on convolutional neural network as coarse prediction. Then, combined with the tree model, the precise prediction is further made for the enterprise credit evaluation. Finally, the model fusion is carried out to obtain high-precision results. In the simulation experiment, this paper takes a data set of 14,366 small and medium-sized enterprise credit evaluations as the analysis samples to verify the results. The accuracy of the model is 97%, which is far more than 93% of single model with metadata set. [ABSTRACT FROM AUTHOR]

As biomaterials, it is essential for polyurethane (PU) to have excellent antibacterial activity and biocompatibility at the same time. Herein, quaternary ammonium groups, sulfonic groups, and alkyl groups simultaneously introduced hyperbranched poly(amidoamine) (HPA‐QSA) was synthesized, which was further used to blend with PU and prepared as films. HPA‐QSA/PU blend films showed strong antibacterial activity to kill more than 99.99% of both Gram‐positive and Gram‐negative bacteria due to the quaternary ammonium groups and long alkyl groups, as well as good biocompatibility through protein‐resistance, cytotoxicity, hemolysis assays under the combined action of cations and anions. Moreover, they exhibited stable antibacterial activity and low cytotoxicity in aquatic solutions. Overall, HPA‐QSA/PU films prepared by facile blending process exhibit great promise as low‐cost, effective antibacterial, good biocompatible materials, indicating an appealing prospect in biomedical fields. [ABSTRACT FROM AUTHOR]

Compounds bearing aliphatic amines can be emissive under appropriate conditions. However, their ionized counterparts, namely, quaternary ammonium salts (QASs), which are widely used as phase‐transfer catalysts, ionic liquids, disinfectants, and surfactants, are known as luminescence quenchers and considered nonemissive. Herein, unprecedented intrinsic fluorescence/phosphorescence dual emissions from various QASs are reported, which can be finely regulated by changing the excitation wavelength, alkyl chain length, counterion, and mechanical stimuli. The bright photoluminescence along with distinct afterglow and tunable multicolor emissions enables the application of QAS solids in advanced multimode anticounterfeiting. This finding refreshes the understanding of QASs and may inspire emerging applications based on the utilization of the intrinsic luminescences of QASs. Furthermore, it opens opportunities for the investigation of QAS‐related processes and functions via a photophysical approach and affords strong implications for the fabrication of novel nonconventional luminophores. [ABSTRACT FROM AUTHOR]

SUMMARY: The leaf veins of higher plants contain a highly specialized vascular system comprised of xylem and phloem cells that transport water, organic compounds and mineral nutrients. The development of the vascular system is controlled by phytohormones that interact with complex transcriptional regulatory networks. Before the emergence of true leaves, the cotyledons of young seedlings perform photosynthesis that provides energy for the sustainable growth and survival of seedlings. However, the mechanisms underlying the early development of leaf veins in cotyledons are still not fully understood, in part due to the complex cellular composition of this tissue. To better understand the development of leaf veins, we analyzed 14 117 single cells from 3‐day‐old cotyledons using single‐cell RNA sequencing. Based on gene expression patterns, we identified 10 clusters of cells and traced their developmental trajectories. We discovered multiple new marker genes and developmental features of leaf veins. The transcription factor networks of some cell types indicated potential roles of CYCLING DOF FACTOR 5 (CDF5) and REPRESSOR OF GA (RGA) in the early development and function of the leaf veins in cotyledons. These new findings lay a foundation for understanding the early developmental dynamics of cotyledon veins. The mechanisms underlying the early development of leaf veins in cotyledons are still not fully understood. In this study, we comprehensively characterized the early differentiation and development of leaf veins in 3‐day‐old cotyledons based on single‐cell transcriptome analysis. We identified the cell types and novel marker genes of leaf veins and characterized the novel regulators of leaf vein. Significance Statement: The mechanisms underlying the early development of leaf veins in cotyledons are still not fully understood. In this study, we comprehensively characterized the early differentiation and development of leaf veins in 3‐day‐old cotyledons based on single‐cell transcriptome analysis. We identified the cell types and novel marker genes of leaf veins, and characterized the novel regulators of leaf vein. [ABSTRACT FROM AUTHOR]

Nonaromatic photoluminescent polymers have attracted great attention due to their intriguing photophysical properties and promising implications in optoelectronic and biological areas. The luminescence from these nonconventional luminophores can be well rationalized by the clustering‐triggered emission mechanism. Sulfur, although as an n‐electron‐rich element with big radius, is not been widely utilized in construction of nonconventional luminophores despite of its potential competitiveness in nonaromatic photoluminescent polymers. Herein, the "click" type Michael polyaddition is utilized to construct sulfur‐bearing nonconventional luminophores, and two sulfur enriched nonaromatic poly(thioether sulfone)s (PES) are obtained, which demonstrate fluorescence‐phosphorescence dual emission. More investigations concerning the monomer of bis(vinylsulfonyl)methane are further proceeded to support acquired results. Finally, the application of explosive detection by the prepared PES is also conducted. [ABSTRACT FROM AUTHOR]

The defect in quality caused by the noncompactness of sleeve grouting has become the main obstacle restricting the further implementation of the prefabricated building in China. Studies have been conducted to explore the influencing factors of inadequate grouting; however, few studies attempt to investigate the complex interrelationship and lack of systematic cognition among these factors. To fill this gap, this study conducted a comprehensive literature review to collect the influencing factors of sleeve grouting and verified the reliability of these factors using the combined methods of brainstorming and semistructured expert discussion. A total of 18 key factors were identified and determined. The structural interpretation model (SIM) and Matrice d'Impacts Croisés Multiplication Appliquée à un Classement (MICMAC) approaches were then used to analyze, depict, and explain the internal relationships between the factors. The results indicate that all factors were classified into six levels, among which poor responsibility of supervisors and weather conditions are the most basic factors, while grouting speed and a loose-sealing rubber plug are the most important factors. Finally, a three-level control strategy was proposed to improve the compactness quality of sleeve grouting. The research findings provide valuable guidelines for managers to eliminate the grouting quality defect and to further the development of prefabricated buildings in China. [ABSTRACT FROM AUTHOR]

Novel emitters that do not contain traditional chromophores but only electron‐rich moieties (e. g. amine, C=O, −OH, ether, and imide), which are classified as nonconventional luminophores, have been more frequently reported. Although more and more examples have been demonstrated, their emission mechanism remains unclear. The clustering‐triggered emission (CTE) mechanism has previously been proposed to rationalize the luminescence of unconventional chromophores. Moreover, great attention has been paid to the distinctive inherent luminescence from nonaromatic biomolecules such as cellulose, starch, sugars, and nonaromatic amino acids and proteins. In this Review, we summarize these unconventional biomolecular luminophores and apply the CTE mechanism to rationalize such a phenomenon. This Review may shed new light on the understanding of intrinsic emission of nonaromatic biomolecules and decipher the intrinsic fluorescence from cells and tissues. [ABSTRACT FROM AUTHOR]

It is a textbook knowledge that protein photoluminescence stems from the three aromatic amino acid residues of tryptophan(Trp), tyrosine (Tyr), and phenylalanine (Phe), with predominant contributions from Trp. Recently, inspired by the intrinsic emission of nonaromatic amino acids and poly(amino acids) in concentrated solutions and solids, we revisited protein light emission using bovine serum albumin (BSA) as a model. BSA is virtually nonemissive in dilute solutions (≤0.1 mg mL−1), but highly luminescent upon concentration or aggregation, showing unique concentration‐enhanced emission and aggregation‐induced emission (AIE) characteristics. Notably, apart from well‐documented UV luminescence, bright blue emission is clearly observed. Furthermore, persistent room‐temperature phosphorescence (p‐RTP) is achieved even in the amorphous solids under ambient conditions. This visible emission can be rationalized by the clustering‐triggered emission (CTE) mechanism. These findings not only provide an in‐depth understanding of the emissive properties of proteins, but also hold strong implications for further elucidating the basis of tissue autofluorescence. [ABSTRACT FROM AUTHOR]

Pure organic luminogens with persistent room‐temperature phosphorescence (p‐RTP) have attracted increasing attention owing to their vital significance and potential applications in security inks, bioimaging, and photodynamic therapy. Previously reported p‐RTP luminogens normally possessed through‐bond conjugation. In this work, we report a pure organic luminogen, AN‐MA, the Diels–Alder cycloaddition adduct of anthracene (AN) and maleic anhydride (MA), which possesses isolated phenyl groups and an anhydride moiety. AN‐MA exhibits aggregation‐enhanced emission (AEE) characteristics with efficiency of approximately 2 % and up to 8.5 % in solution and crystals, respectively. Two polymorphs of AN‐MA were readily obtained that were able to generate UV emission from individual phenyl rings together with bright blue emission owing to the effective through‐space conjugation. Moreover, p‐RTP with a lifetime of up to approximately 1.6 s was obtained in the crystals. These results not only reveal a new system with both fluorescence and RTP dual emission but also suggest an alternative through‐space conjugation strategy towards pure organic p‐RTP luminogens with tunable emissions. Spatial relations: A pure organic luminogen (AN‐MA) with isolated small conjugates and effective through‐space conjugation was obtained through facile Diels–Alder cycloaddition. Owing to its flexible structure, two polymorphs were readily obtained. These exhibit bright visible emission and persistent room‐temperature phosphorescence (p‐RTP) (see figure). [ABSTRACT FROM AUTHOR]

The daily air temperature and precipitation records of four meteorological observation stations over China are used to investigate the differences of scaling property employing the detrended fluctuation analysis (DFA) method. The results show that the values in DFA-exponent for temperature are higher than those for precipitation compared by different orders DFA1–3. A 95% significance test is also applied to verify LRCs by resampling the temperature and precipitation records 10000 times in Beijing. The values of scaling exponent from original temperature and precipitation records are larger than the upper range value of the interval threshold after shuffling the data records, which implies there are positive LRCs. For temperature records, the value of scaling exponent calculated by FA is greater than those by DFA1–3 at all four stations. This indicates that the FA curve overestimates the scaling behavior due to the effect of trends. By contrast, the values of scaling exponent in precipitation are almost the same by using FA and DFA1–3 for all time scales, respectively. Furthermore, there are crossovers on short time scales in different orders DFA1–3 for the temperature records, while the slopes keep almost consistent on all time scales for the precipitation records. [ABSTRACT FROM AUTHOR]

Directly using the promoter associated with 5′-untranslated region of a high-protein-abundance gene from the genome may cause low expression activity of an expression system. A bicistronic expression part containing the short 5′ coding sequence of the source gene and an embedded Shine-Dalgarno sequence can cause higher expression levels of the recombinant gene in a bicistronic cassette. Here, we evaluated two methods to construct expression parts and exploited genomic sequence sources to provide specific functional sequences to complete the expression system. The architecture of the bicistronic part increased the expression levels of target genes and performed more reliably than conventional expression parts with the same promoter and 5′ untranslated region. For Corynebacterium glutamicum, the strongest bicistronic part, HP-BEP4, was obtained from a heterologous sequence source, leading to a 2.24-fold increase in the expression level of fluorescent protein over constitutively expressed pXMJ19 or the production of more than 100 mg/L single-chain variable fragment (scFv). It could meet the needs of overexpressing key genes in C. glutamicum. [ABSTRACT FROM AUTHOR]

To test the hypothesis that different drivers shape the diversity and biogeography of the total and active bacterial community, we examined the bacterial community composition along two transects, one from the inner Pearl River estuary to the open waters of the South China Sea ( SCS) and the other from the Luzon Strait to the SCS basin, using 454 pyrosequencing of the 16S r RNA and 16S r RNA gene (V1-3 regions) and thereby characterizing the active and total bacterial community, respectively. The diversity and biogeographic patterns differed substantially between the active and total bacterial communities. Although the composition of both the total and active bacterial community was strongly correlated with environmental factors and weakly correlated with geographic distance, the active bacterial community displayed higher environmental sensitivity than the total community and particularly a greater distance effect largely caused by the active assemblage from deep waters. The 16S r RNA vs. r DNA relationships indicated that the active bacteria were low in relative abundance in the SCS. This might be due to a high competition between active bacterial taxa as indicated by our community network models. Based on these analyses, we speculate that high competition could cause some dispersal limitation of the active bacterial community resulting in a distinct distance-decay relationship. Altogether, our results indicated that the biogeographic distribution of bacteria in the SCS is the result of both environmental control and distance decay. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries possess high theoretical energy density, whereas the shuttle effect of polysulfides and the uncontrollable lithium (Li) dendrites seriously reduce the reversible capacity and cycling lifespan. Constructing an interphase to address the issues in both the cathode and anode simultaneously is significant but still challenging. In this study, a strategy of functionalizing commercial polypropylene (PP) separators is proposed by in situ poly(thioctic acid) (PTA) polymerization. Compared with the conventional separator modifications, the ring‐opening polymerization methodology initiated by heat is more facile and environment‐friendly without changing the nanostructures among the porous separators. On the cathode side, the PTA‐coated separator (PTA‐PP) blocks the shuttle of polysulfides through the electrostatic interaction. On the anode side, the PTA‐coated generates a lithium fluoride (LiF)‐rich solid electrolyte interface (SEI), identified by cryo‐transmission electron microscopy (cryo‐TEM), to accelerate the Li+ diffusion and inhibit the growth of Li dendrites. Due to the interphases constructed by the PTA‐PP separator, the Li–S cells exhibit excellent long‐term cycling in which the capacity retention rate is more than 76% after 700 cycles at 0.5 C. The in situ elaborate modification strategy may provide insights into the high‐performance separator design to promote the potentially large‐scale applications of Li–S batteries. [ABSTRACT FROM AUTHOR]