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Fluorescent imaging and biosensing in the near‐infrared‐II (NIR‐II) window holds great promise for non‐invasive, radiation‐free, and rapid‐response clinical diagnosis. However, it's still challenging to develop bright NIR‐II fluorophores. In this study, we report a new strategy to enhance the brightness of NIR‐II aggregation‐induced emission (AIE) fluorophores through intramolecular electrostatic locking. By introducing sulfur atoms into the side chains of the thiophene bridge in TSEH molecule, the molecular motion of the conjugated backbone can be locked through intramolecular interactions between the sulfur and nitrogen atoms. This leads to enhanced NIR‐II fluorescent emission of TSEH in both solution and aggregation states. Notably, the encapsulated nanoparticles (NPs) of TSEH show enhanced brightness, which is 2.6‐fold higher than TEH NPs with alkyl side chains. The in vivo experiments reveal the feasibility of TSEH NPs in vascular and tumor imaging with a high signal‐to‐background ratio and precise resection for tiny tumors. In addition, polystyrene nanospheres encapsulated with TSEH are utilized for antigen detection in lateral flow assays, showing a signal‐to‐noise ratio 1.9‐fold higher than the TEH counterpart in detecting low‐concentration antigens. This work highlights the potential for developing bright NIR‐II fluorophores through intramolecular electrostatic locking and their potential applications in clinical diagnosis and biomedical research. [ABSTRACT FROM AUTHOR]

Zero‐dimensional nitrogen‐doped carbon dots (N‐CDs) have been proved effective when introduced into the polymerization system of aniline as the hard template to synthesis small‐sized, monodisperse and highly conductive N‐CDs/PANI (N‐CDs/PANI) nanocomposites, which were then added into acrylic (AC) resin to produce coatings with excellent corrosion resistance and antifouling performances in this paper. Compared with the PANI, the N‐CDs/PANI did show remarkably improved anticorrosion and antifouling properties. The protection efficiency of the AC resin coating was increased by 5 times and to 57.3% with the addition of the N‐CDs/PANI, which is higher than that of the AC resin coating, about 37.0%, with the addition of the PANI. In addition, the AC resin coating containing N‐CDs/PANI exhibited additional antifouling properties with an algae inhibition rate of about 24.6%, since the redox property of the carbon dots could destroy the photosynthesis of microorganisms such as Chlorella. Furthermore, because that the N‐CDs/PANI had better dispersibility than PANI and could be more uniformly dispersed in the AC resin, the adhesion of the N‐CDs/PANI‐AC coating was better than that of the PANI‐AC coating. [ABSTRACT FROM AUTHOR]

Robotic materials, with coupled sensing, actuation, computation, and communication, have attracted increasing attention because they are able to not only tune their conventional passive mechanical property via geometrical transformation or material phase change but also become adaptive and even intelligent to suit varying environments. However, the mechanical behavior of most robotic materials is either reversible (elastic) or irreversible (plastic), but not transformable between them. Here, a robotic material whose behavior is transformable between elastic and plastic is developed, based upon an extended neutrally stable tensegrity structure. The transformation does not depend on conventional phase transition and is fast. By integrating with sensors, the elasticity‐plasticity transformable (EPT) material is able to self‐sense deformation and decides whether to undergo transformation or not. This work expands the capability of the mechanical property modulation of robotic materials. [ABSTRACT FROM AUTHOR]

The immunoproteasome is a specialized type of proteasome involved in MHC class I antigen presentation, antiviral adaptive immunity, autoimmunity, and is also part of a broader response to stress. Whether the immunoproteasome is regulated by DNA stress, however, is not known. We here demonstrate that mitochondrial DNA stress upregulates the immunoproteasome and MHC class I antigen presentation pathway via cGAS/STING/type I interferon signaling resulting in cell autonomous activation of CD8+ T cells. The cGAS/STING‐induced adaptive immune response is also observed in response to genomic DNA and is conserved in epithelial and mesenchymal cells of mice and men. In patients with idiopathic pulmonary fibrosis, chronic activation of the cGAS/STING‐induced adaptive immune response in aberrant lung epithelial cells concurs with CD8+ T‐cell activation in diseased lungs. Genetic depletion of the immunoproteasome and specific immunoproteasome inhibitors counteract DNA stress induced cytotoxic CD8+ T‐cell activation. Our data thus unravel cytoplasmic DNA sensing via the cGAS/STING pathway as an activator of the immunoproteasome and CD8+ T cells. This represents a novel potential pathomechanism for pulmonary fibrosis that opens new therapeutic perspectives. Synopsis: Immunoproteasomes are activated by interferons and involved in MHC class I‐mediated CD8+ T‐cell activation as part of antiviral immune responses. This study demonstrates that cytoplasmic DNA sensing by the cGAS/STING pathway induces immunoproteasome‐mediated activation of CD8+ T cells that may be involved in idiopathic pulmonary fibrosis. Sensing of intracellular mitochondrial and genomic DNA via the cGAS/STING pathway activates the immunoproteasome and MHC class I antigen presentation in human and murine epithelial cells and fibroblasts.cGAS/STING activation induces CD8+ T cell adaptive immune responses in a cell‐autonomous manner.Immunoproteasomes and CD8+ T cells are activated in lungs of patients with idiopathic pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

The extensive utilization of fluorine industrial products has brought abundant fluorine pollution. The fluorine removal is important. In this study, CaO, as a novel coprecipitator, was conducted to synthesize Ca‐Fe‐SO4 layered double hydroxide (CF) via co‐precipitation of FeSO4. Ca‐Fe mixed metal oxide adsorbent (CCF) was fabricated by calcinating CF for efficient fluoride adsorption. The results showed that CCF adsorbent had an excellent adsorption performance for fluoride. It was attributed to two reasons as follows: On one hand, Ca had a strong affinity for fluoride, improving the adsorption capacity of adsorbent for fluoride. On the other hand, Fe had a strong magnetism, which could promote the recovery of the adsorbed material. The adsorption capacity of CCF for fluorine was analyzed by batch adsorption experiments, the adsorption capacity was 160.66 mg/g at temperature of 298 K and pH of 7. Moreover, the adsorption process of fluorine and the actual adsorption process were in accordance with Langmuir model and the pseudo‐second‐order kinetic model, respectively. According to the analysis of pHzpc, FITR and XPS, the main adsorption mechanisms of CCF for fluoride in water were complexation and electrostatic interactions. Therefore, this study suggested that CaO can be a novel coprecipitator to prepare a new efficient fluorine adsorbent for the treatment of industrial wastewater. [ABSTRACT FROM AUTHOR]

Summary: Our previous study using transposon mutagenesis indicated that disruption of the putative response regulator gene orrA impacted antibiotic production in Streptomyces coelicolor. In this study, the role of OrrA was further characterized by comparing the phenotypes and transcriptomic profiles of the wild‐type S. coelicolor strain M145 and ΔorrA, a strain with an inactivated orrA gene. Chromatin immunoprecipitation using a strain expressing OrrA fused with FLAG showed that OrrA binds the promoter of wblA, whose expression was downregulated in ΔorrA. The interaction of OrrA with the wblA promoter was further validated by a pull‐down assay. Similar to ΔorrA, the deletion mutant of wblA (ΔwblA) was defective in development, and developmental genes were expressed at similar levels in ΔorrA and ΔwblA. Although both OrrA and WblA downregulated actinorhodin and undecylprodigiosin, their roles in regulation of the calcium‐dependent antibiotic and yellow‐pigmented type I polyketide differed. sco1375, a gene of unknown function, was identified as another OrrA target, and overexpression of either sco1375 or wblA in ΔorrA partially restored the wild‐type phenotype, indicating that these genes mediate some of the effects of OrrA. This study revealed targets of OrrA and provided more insights into the role of the orphan response regulator OrrA in Streptomyces. [ABSTRACT FROM AUTHOR]

Triple‐negative breast cancer (TNBC) is a highly aggressive and metastatic malignancy with poor treatment outcomes. The interaction between the tumor microenvironment (TME) and breast cancer stem cells (BCSCs) plays an important role in the development of TNBC. Owing to their ability of self‐renewal and multidirectional differentiation, BCSCs maintain tumor growth, drive metastatic colonization, and facilitate the development of drug resistance. TME is the main factor regulating the phenotype and metastasis of BCSCs. Immune cells, cancer‐related fibroblasts (CAFs), cytokines, mesenchymal cells, endothelial cells, and extracellular matrix within the TME form a complex communication network, exert highly selective pressure on the tumor, and provide a conducive environment for the formation of BCSC niches. Tumor growth and metastasis can be controlled by targeting the TME to eliminate BCSC niches or targeting BCSCs to modify the TME. These approaches may improve the treatment outcomes and possess great application potential in clinical settings. In this review, we summarized the relationship between BCSCs and the progression and drug resistance of TNBC, especially focusing on the interaction between BCSCs and TME. In addition, we discussed therapeutic strategies that target the TME to inhibit or eliminate BCSCs, providing valuable insights into the clinical treatment of TNBC. [ABSTRACT FROM AUTHOR]

B Elasticity-Plasticity Transformation b The behavior of most materials is either reversible (elastic) or irreversible (plastic), but not switchable. In article number 2206637 by Xinyuan Wang, Zhiqiang Meng, and Chang Qing Chen, a robotic material that can switch between elasticity and plasticity is demonstrated. [Extracted from the article]

SUMMARY: Carotenoids are photosynthetic pigments and antioxidants that contribute to different plant colors. However, the involvement of TOPLESS (TPL/TPR)‐mediated histone deacetylation in the modulation of carotenoid biosynthesis through ethylene‐responsive element‐binding factor‐associated amphiphilic repression (EAR)‐containing transcription factors (TFs) in apple (Malus domestica Borkh.) is poorly understood. MdMYB44 is a transcriptional repressor that contains an EAR repression motif. In the present study, we used functional analyses and molecular assays to elucidate the molecular mechanisms through which MdMYB44‐MdTPR1‐mediated histone deacetylation influences carotenoid biosynthesis in apples. We identified two carotenoid biosynthetic genes, MdCCD4 and MdCYP97A3, that were confirmed to be involved in MdMYB44‐mediated carotenoid biosynthesis. MdMYB44 enhanced β‐branch carotenoid biosynthesis by repressing MdCCD4 expression, whereas MdMYB44 suppressed lutein level by repressing MdCYP97A3 expression. Moreover, MdMYB44 partially influences carotenoid biosynthesis by interacting with the co‐repressor TPR1 through the EAR motif to inhibit MdCCD4 and MdCYP97A3 expression via histone deacetylation. Our findings indicate that the MdTPR1‐MdMYB44 repressive cascade regulates carotenoid biosynthesis, providing profound insights into the molecular basis of histone deacetylation‐mediated carotenoid biosynthesis in plants. These results also provide evidence that the EAR‐harboring TF/TPL repressive complex plays a universal role in histone deacetylation‐mediated inhibition of gene expression in various plants. Significance Statement: MdMYB44 regulated carotenoid biosynthesis partially by interacting with co‐repressor TPR1 via EAR motif to inhibit MdCCD4 and MdCYP97A3 expression through histone deacetylation, providing evidence that the EAR‐harboring TF/TPL repressive complex has a universal role in histone deacetylation‐mediated gene expression inhibition in various plants. [ABSTRACT FROM AUTHOR]

High‐optical‐quality ternary [(Y1‐xGdx)0.99Dy0.01]2O3 (x = 0 and 0.4) ceramics were successfully fabricated by vacuum sintering with in‐line transmittances of 71.4%‐75.1% at 574 nm, the wavelength of Dy3+ emission (the 4F9/2 → 6H13/2 transition). Substitution of Gd3+ for Y3+ significantly affected the photoluminescent and scintillant properties of the ceramics. Gd3+ addition effectively increased lattice parameters and theoretical densities of the ceramic samples; this contributed to enhanced X‐ray absorption coefficients. Both [(Y1‐xGdx)0.99Dy0.01]2O3 (x = 0 and 0.4) ceramics displayed typical Dy3+ emissions from 4F9/2 → 6HJ (J = 15/2, 13/2, 11/2) transitions under UV and X‐ray irradiations. By incorporating Gd3+ into the lattice, a stronger excitation peak of Gd3+ due to internal f‐f transitions relative to Dy3+ was observed at 276 nm; subsequent ceramics obtained a sharper PL intensity and a warmer hue via effective energy transfer from Gd3+ to Dy3+. Using a Gd3+ dopant generally reduces the total photoluminescence/photoluminescence excitation intensities and light output; it also delays the lifetime and afterglow of the transparent ceramics. [ABSTRACT FROM AUTHOR]

Tumor‐targeted photodynamic therapy (PDT) is desirable as it can achieve efficient killing of tumor cells with no or less harm to normal cells. Herein, a facile molecular engineering strategy is developed for photosensitizers (PSs) with aggregation induced emission (AIE) characteristics and responsive properties to the acidic tumor microenvironment (TME). By the marriage of pH‐sensitive sulfonamide moieties with AIE PSs, two near‐infrared AIE luminogens called DBP‐SPy and DBP‐SPh are designed and synthesized. Both luminogens can form negatively charged nanoaggregates in the aqueous medium at physiological pH. The DBP‐SPy nanoaggregates undergo surface charge conversion to become positive at pH close to the signature pH of TME, while DBP‐SPh nanoaggregates show no such property. The endowed response to acidic TME enables the enhanced cellular uptake of DBP‐SPy at pH = 6.8. By contrast, its cellular uptake is much sacrificed at pH 7.4. As a result, under white light irradiation, DBP‐SPy nanoaggregates demonstrate a considerable photodynamic therapeutic effect on cancer cells in vitro and excellent tumor growth inhibition in vivo. Hence, this study not only provides an acidic TME‐responsive AIE PS for precise PDT, but also inspires new design strategies for AIE‐based theragnostic systems with targeting characteristics. [ABSTRACT FROM AUTHOR]

The one‐stage detectors achieve a good trade‐off between performance and latency, owing to the plain architecture and divergent learning mechanism for classification and localization. However, the two sub‐tasks require features with various inherency with which to generate inconsistent detections, fettering detectors. In this study, the misalignment is deeply analyzed via kernel density estimation (KDE) for the first time. Moreover, to address the misalignment, a plug‐and‐play detection head, named Diff‐Head, is devised and embedded in one‐stage detectors. Concretely, the authors merge parallel branches into a semi‐parallel structure, establishing the correlation between classification and regression. In the regression branch, a feature difference module (FDM) gets rid of the features that favour classification by subtracting salient object features from the original feature map, and position encoding (PE) modules enhance the absolute position information. The flexibility and efficiency of the detection head are retained. Experiments on Pascal visual object classes (VOC) and MS COCO demonstrate that Diff‐Head is effective and achieves competitive performance with state‐of‐the‐art detectors. Meanwhile, the amount of parameters is reduced at least 30% and 83.0% average precision (AP) is achieved on Pascal VOC. The analyses of consistency and error show that Diff‐Head has better localization and the capability of mitigating the misalignment. [ABSTRACT FROM AUTHOR]

Li‐ion hybrid supercapacitors (LHSCs) are intensely studied due to their favorable power densities. However, combined higher energy density materials, particularly anodes, are desirably sought. Herein, a defect‐dominating structure protocol is reported. Specifically, two visible structural defects, i.e., crystal vacancy and lattice distortion have been introduced in situ in ultrafine niobium nitride (NbN) monocrystals that are integrated into a carbon (C) framework. Highly reversible Li‐ion storage capacities up to 540 mAh g−1 are demonstrated in such a NbN@C composite anode, together with excellent rate capability and cycling stability. An extra vacancy‐induced capacity contribution of the defective NbN component is evidenced by first‐principles density functional theory (DFT) simulations in contrast to perfect modeling. Coupling with an activated carbon (AC) cathode, the NbN@C//AC cell can deliver balanced energy and power densities of 53.8 Wh kg−1 and 7818 W kg−1 at 4 A g−1, and retain a desired energy density of 56.1 Wh kg−1 after 10 000 cycles at 1 A g−1. Findings from this study, particularly the demonstrated defects‐induced extra capacity of pseudocapacitive materials, may inspire new structural material designs of LHSCs. [ABSTRACT FROM AUTHOR]

Summary: Phosphate metabolism is known to be regulated by the PhoPR regulatory system in Streptomyces and some other bacteria. In this study, we report that MtrA also regulates phosphate metabolism in Streptomyces. Our data showed that, in Streptomyces coelicolor, MtrA regulates not only phosphate metabolism genes such as phoA but also phoP under different phosphate conditions, including growth on rich complex media without added inorganic phosphate and on defined media with low or high concentrations of inorganic phosphate. Cross‐regulation was also observed among mtrA, phoP and glnR under these conditions. We demonstrated both in vitro and in vivo binding of MtrA to the promoter regions of genes associated with phosphate metabolism and to the intergenic region between phoR and phoU, indicating that these phosphate metabolism genes are targets of MtrA. We further showed that MtrA in S. lividans and S. venezuelae has detectable regulatory effects on expression of phosphate metabolism genes. Additionally, the MtrA homologue from Corynebacterium glutamicum bound predicted MtrA sites of multiple phosphate metabolism genes, implying its potential for regulating phosphate metabolism in this species. Overall, our findings support MtrA as a major regulator for phosphate metabolism in Streptomyces and also potentially in other actinobacteria. [ABSTRACT FROM AUTHOR]

In this work, chromium coating conducted by magnetron sputtering was introduced to braze SiC ceramics using inactive AgCu filler metal. The results showed that reliable metallurgical bonding of SiC ceramics was obtained at 900°C for 10 minutes. SEM, XRD, and TEM were used to identify the reaction phase in the joint, and the typical interfacial microstructure was SiC/mixed CrSi2 + Cr23C6 layer/CrSi2/Ag(s,s)+Cu(s,s)/CrSi2/mixed CrSi2 + Cr23C6 layer/SiC. The shear strength of SiC joint using chromium coating brazed with inactive AgCu filler metal was 29.6 MPa and the joint fractured at the SiC substrate entirely after shear test. The proposed active element coating method provides a feasible way to achieve the brazing of ceramics. [ABSTRACT FROM AUTHOR]

Radiation‐induced pulmonary fibrosis (RIPF) is a life‐threatening complication of thoracic radiotherapy, which contributes to continued deterioration in pulmonary function. Sphingosine‐1 phosphate receptor 3 (S1PR3) has been identified as a crucial molecule in fibrosis. Accumulating evidence indicated that the inhibition of the S1PRs ameliorates fibrogenesis. Thus, this study aims to explore whether S1PR3 participates in RIPF and elucidates the molecular mechanisms underlying S1PR3‐modulated epithelial–mesenchymal transition (EMT) in transforming growth factor‐β1‐induced pulmonary epithelia. A recombinant adeno‐associated viral‐mediated S1PR3 (AAV‐S1PR3) gene therapy analyzed the effect of S1PR3 gene deficiency on the altered histology structure and molecular mechanisms in the lung of mice with whole‐lung irradiation. Compared with the AAV‐negative control mice, AAV‐mediated S1PR3 knockdown in the lung of mice attenuated pulmonary fibrosis induced by the radiation, as indicated by the alleviation of collagen accumulation, lessened histopathological alterations, and the suppression of inflammatory cells infiltration. S1PR3 deficiency reversed the RIPF concomitantly with abrogated EMT‐related protein (α‐smooth muscle actin). Consistently, S1PR3‐deficient pulmonary epithelia inhibited the EMT process changes and fibrosis formation. Furthermore, S1PR3 was designated as one of the target genes for microRNA‐495‐3p (miR‐495‐3p). The inhibition of miR‐495‐3p promoted the expression of S1PR3 in pulmonary epithelia, whereas the overexpression of miR‐495‐3p inhibited the S1PR3/SMAD2/3 pathway and suppressed the EMT process. Collectively, miR‐495‐3p might be a negative regulator of the EMT process in fibrosis formation by inhibiting the targeted S1PR3 gene. These results established a link between the S1PR3 gene, the EMT process, and the fibrosis, suggesting the pharmacological blockage of S1PR3 as a potential therapeutic strategy for RIPF. [ABSTRACT FROM AUTHOR]

Summary: In Streptomyces, GlnR is an activator protein that activates nitrogen‐assimilation genes under nitrogen‐limiting conditions. However, less is known regarding the regulation of these genes under nitrogen‐rich conditions. We determined that the developmental regulator MtrA represses nitrogen‐assimilation genes in nitrogen‐rich media and that it competes with GlnR for binding to GlnR boxes. The GlnR boxes upstream of multiple nitrogen genes, such as amtB, were confirmed as MtrA binding sites in vitro by electrophoretic mobility shift assays and in vivo by ChIP‐qPCR analysis. Transcriptional analysis indicated that, on nutrient‐rich medium, MtrA profoundly repressed expression of nitrogen‐associated genes, indicating opposing roles for MtrA and GlnR in the control of nitrogen metabolism. Using in vitro and in vivo analysis, we also showed that glnR is itself a direct target of MtrA and that MtrA represses glnR transcription. We further demonstrated functional conservation of MtrA homologues in the recognition of GlnR boxes upstream of nitrogen genes from different actinobacterial species. As mtrA and glnR are widespread among actinomycetes, this mechanism of potential competitive control over nitrogen metabolism genes may be common in this group, adding a major new layer of complexity to the known regulatory network for nitrogen metabolism in Streptomyces and related species. [ABSTRACT FROM AUTHOR]

With the increasing complexity of engineering systems, reliability analysis and evaluation of systems with traditional methods can't meet practical engineering requirements. Based on limited experimental conditions, lack of data, complex structure models, insufficient cognitive abilities, and many other issues, people have to consider many uncertain factors in system reliability research. Besides, common cause failure (CCF) has become an important factor of system failure. In this paper, a discrete‐time Bayesian network (DTBN) associated with an eight‐rotor unmanned aerial vehicle (UAV) system is presented to discuss above problems. In this approach, the system is assumed as a two‐state system. After that, interval analysis theory is employed to deal with uncertainty. We consider the four sets of auxiliary propellers in the auxiliary power group as a 3/8 voting system, and β factor model is used to process CCF in the auxiliary power group. The proposed methods prove the validity of proposing interval analysis theory to solve uncertain problems and it is necessary to consider reducing or avoiding CCFs in system. [ABSTRACT FROM AUTHOR]

The new Hoveyda-Grubbs type ruthenium carbene catalyst exhibits excellent performance for both ring-closing and cross metathesis reactions. [ABSTRACT FROM AUTHOR]