Efficient circularly polarized multiple resonance thermally activated delayed fluorescence from B,N-embedded hetero[8]helicene enantiomers.

Helicene-based circularly polarized multiple resonance thermally activated delayed fluorescence (CP-MR-TADF) materials are promising for ultra-high-definition and 3D displays, but most of them encounter potential problems such as easy racemization during the thermal deposition process, low luminous efficiency, and low luminescence dissymmetry factor (g lum), making the development of efficient circularly polarized organic light-emitting diodes (CP-OLEDs) a significant challenge. Here, we report a pair of CP-MR-TADF enantiomers with high-order B,N-embedded hetero[8]helicene, (P/M)-BN-TP-ICz, by fusing two MR chromophores, DtCzB and indolo[3,2,1-jk]carbazole (ICz). BN-TP-ICz exhibits green emission in toluene with a peak of 531 nm and a full-width at half-maximum (FWHM) of 36 nm. The optimized CP-OLEDs with enantiomers (P/M)-BN-TP-ICz exhibit green emission with peaks of 540 nm, FWHMs of 38 nm and Commission Internationale de L'Eclairage coordinates of (0.33, 0.65). Moreover, they showcase maximum external quantum efficiencies (EQEs) of 32.0%, with g ELs of +6.49 × 10-4 and -7.74 × 10-4 for devices based on (P)-BN-TP-ICz- and (M)-BN-TP-ICz, respectively.

Clar's Aromatic π-Sextet Rule for the Construction of Red Multiple Resonance Emitter.

Despite the proliferation of multiple resonance (MR) materials in the blue to green spectral ranges, red MR emitters remain scarce in the literature, an area that certainly warrants attention for future applications. Here, through a clever application of classic Clar's aromatic π-sextet rule, we triumphantly constructed the first red MR emitter by substituting the conventional benzene ring core with anthracene (fewer π-sextets). Theoretical studies indicate that the quantity of π-sextets ultimately determines the optical bandgap of a molecule, rather than the number of fused benzene rings. Benefiting from the high photoluminescence quantum yield of ~94% and horizontal dipole ratio of ~90%, the corresponding narrowband red (luminescence wavelength: 608 nm) organic light-emitting diode shows a high external quantum efficiency of 27.3%, with only a slight decrease of 3.7% at an elevated luminance level of 100,000 cd/m2.

Bioactive components in prunella vulgaris for treating Hashimoto's disease via regulation of innate immune response in human thyrocytes.

Background: Hashimoto's thyroiditis (HT) is a thyroid autoimmune disease characterized by lymphocytic infiltration and thyroid destruction. Prunella vulgaris (PV) is a traditional Chinese herbal medicine with documented clinical efficacy in treating HT. We previously reported an immunoregulatory effect of PV in thyrocytes; however, the bioactive components of PV remained unclear. This study aimed to elucidate key components of PV for treating HT and their acting mechanisms. Methods: Network pharmacology was used to predict key PV components for HT. The predicted components were tested to determine whether they could exert an immunoregulatory effect of PV in human thyrocytes. Limited proteolysis-mass spectrometry (Lip-MS) was used to explore interacting proteins with PV components in human thyrocytes. Microscale thermophoresis binding assay was used to evaluate the affinity of PV components with the target protein. Results: Eleven PV components with 192 component targets and 3415 HT-related genes were gathered from public databases. With network pharmacology, a 'component-target-disease' network was established wherein four flavonoids including quercetin, luteolin, kaempferol, morin, and a phytosterol, ß-sitosterol were predicted as key components in PV for HT. In stimulated primary human thyrocytes or Nthy-ori-31 cells, key components inhibited gene expressions of inflammatory cytokines including tumor necrosis factor α (TNF-α), interleukin-6 (IL-6), and interferon-ß (IFN-ß), cellular apoptosis, and activation of nuclear factor κB (NF-κB) and interferon regulatory factor 3 (IRF-3). Heat shock protein 90 alpha, class A, member 1 (HSP90AA1), was identified to interact with flavonoids in PV by Lip-MS. Morin had the highest affinity with HSP90AA1 (KD = 122.74 µM), followed by kaempferol (KD = 168.53 µM), luteolin (KD = 293.94 µM), and quercetin (KD = 356.86 µM). Conclusion: Quercetin, luteolin, kaempferol, morin, and ß-sitosterol reproduced an anti-inflammatory and anti-apoptosis effect of PV in stimulated human thyrocytes, which potentially contributed to the treatment efficacy of PV in HT.

Modularly Precise Construction of B,N-Embedded Large-Sized Polycyclic Aromatic Hydrocarbon Nanographene.

A modular "fjord-stitching" reverse strategy has been disclosed to successfully prepare two large-sized B,N-embedded nanographenes: BN-TBTi and BN-TBTo. These two compounds both exhibit excellent stability, nonzero-bandgap and decent photoluminescence quantum yield. Single crystal structure of BN-TBTo features a large C78B2N4 π-skeleton with length and width of approximately 2.4 and 1.5 nm, respectively.

Prototypical innate immune mechanism hijacked by leukemia-initiating mutant stem cells for selective advantage and immune evasion in Ptpn11-associated juvenile myelomonocytic leukemia.

Juvenile myelomonocytic leukemia (JMML), a clonal hematologic malignancy, originates from mutated hematopoietic stem cells (HSCs). The mechanism sustaining the persistence of mutant stem cells, leading to leukemia development, remains elusive. In this study, we conducted comprehensive examination of gene expression profiles, transcriptional factor regulons, and cell compositions/interactions throughout various stages of tumor cell development in Ptpn11 mutation-associated JMML. Our analyses revealed that leukemia-initiating Ptpn11 E76K/+ mutant stem cells exhibited de novo activation of the myeloid transcriptional program and aberrant developmental trajectories. These mutant stem cells displayed significantly elevated expression of innate immunity-associated anti-microbial peptides and pro-inflammatory proteins, particularly S100a9 and S100a8. Biological experiments confirmed that S100a9/S100a8 conferred a selective advantage to the leukemia-initiating cells through autocrine effects and facilitated immune evasion by recruiting and promoting immune suppressive myeloid-derived suppressor cells (MDSCs) in the microenvironment. Importantly, pharmacological inhibition of S100a9/S100a8 signaling effectively impeded leukemia development from Ptpn11 E76K/+ mutant stem cells. These findings collectively suggest that JMML tumor-initiating cells exploit evolutionarily conserved innate immune and inflammatory mechanisms to establish clonal dominance.

Tetraniliprole resistance in field-collected populations of Tuta absoluta (Lepidoptera: Gelechiidae) from China: Baseline susceptibility, cross-resistance, inheritance, and biochemical mechanism.

Tuta absoluta is one of the most destructive and invasive insect pests throughout the world. It feeds on numerous solanaceous plant species and has developed resistance to most types of popular insecticides. Tetraniliprole is a novel diamide chemical agent that acts as a modulator of the ryanodine receptor. To establish T. absoluta susceptibility to tetraniliprole and to understand potential mechanisms of resistance, we monitored 18 field populations of T. absoluta collected from northern China. One field-evolved resistant population, Huailai (HL), showed moderate resistance to tetraniliprole (36.2-fold) in comparison with susceptible strain YN-S. Assays of cross-resistance, synergism, metabolic enzyme activity, and inheritance of resistance were performed with YN-S strain and HL population. The latter displayed 12.2- and 6.7-fold cross-resistance to chlorantraniliprole and flubendiamide, respectively, but little cross-resistance to broflanilide (1.6-fold), spinosad (2.1-fold), metaflumizone (1.5-fold), or indoxacarb (2.8-fold). Genetic analyses revealed that tetraniliprole resistance in HL population was autosomal, incompletely dominant, and polygenic. Piperonyl butoxide was found to significantly increase tetraniliprole toxicity, and enzymatic activities of P450 monooxygenase and glutathione S-transferase were significantly higher in HL than YN-S population. These results enhance our knowledge of the inheritance and mechanism of tetraniliprole resistance, enabling future optimization of resistance management strategies.

Baseline of susceptibility, risk assessment, biochemical mechanism, and fitness cost of resistance to dimpropyridaz, a novel pyridazine pyrazolecarboxamide insecticide, in Bemisia tabaci from China.

Bemisia tabaci is one of the most destructive agricultural insect pests around the world, and it has developed high levels of resistance to most pesticides. Dimpropyridaz, a novel insecticide developed by BASF, displays excellent activity against piercing-sucking insect pests. In this study, baseline of susceptibility showed all tested field populations of B. tabaci are susceptible to dimpropyridaz. After continuous selection with dimpropyridaz in the lab, a B. tabaci strain (F12) developed 2.2-fold higher level of resistance compared with a susceptible MED-S strain, and the realized heritability (h2) was estimated as 0.0518. The F12 strain displayed little cross-resistance to afidopyropen, cyantraniliprole, sulfoxaflor, or abamectin, and significantly increased activity of cytochrome P450 monooxygenase (P450). The fitness cost of dimpropyridaz resistance was evident in F12 strain, which had a relative fitness of 0.95 and significantly lower fecundity per female compared with MED-S strain. Taken together, B. tabaci displays high susceptibility to dimpropyridaz in the field, and low risk of developing resistance to dimpropyridaz under successive selection pressure. Little cross-resistance to popular insecticides was found, and fitness cost associated dimpropyridaz resistance was observed. Higher activity of cytochrome P450 in the F12 strain, may be involved in the process of detoxifying dimpropyridaz in whitefly.

Genetically predicted metabolites mediate the causal associations between autoimmune thyroiditis and immune cells.

Introduction: We aimed to comprehensively investigate the causal relationship between 731 immune cell traits and autoimmune thyroiditis (AIT) and to identify and quantify the role of 1400 metabolic traits as potential mediators in between. Methods: Using summary-level data from genome-wide association studies (GWAS) we performed a two-sample bidirectional Mendelian randomization (MR) analysis of genetically predicted AIT and 731 immune cell traits. Furthermore, we used a two-step MR analysis to quantify the proportion of the total effects (that the immune cells exerted on the risk of AIT) mediated by potential metabolites. Results: We identified 24 immune cell traits (with odds ratio (OR) ranging from 1.3166 6 to 0.6323) and 10 metabolic traits (with OR ranging from 1.7954 to 0.6158) to be causally associated with AIT, respectively. Five immune cell traits (including CD38 on IgD+ CD24-, CD28 on CD28+ CD45RA+ CD8br, HLA DR+ CD4+ AC, TD CD4+ %CD4+, and CD8 on EM CD8br) were found to be associated with the risk of AIT, which were partially mediated by metabolites (including glycolithocholate sulfate, 5alpha-androstan-3alpha,17beta-diol disulfate, arachidonoylcholine, X-15486, and kynurenine). The proportion of genetically predicted AIT mediated by the identified metabolites could range from 5.58% to 17.7%. Discussion: Our study identified causal associations between AIT and immune cells which were partially mediated by metabolites, thus providing guidance for future clinical and basic research.

SHP2 as a primordial epigenetic enzyme expunges histone H3 pTyr-54 to amend androgen receptor homeostasis.

Mutations that decrease or increase the activity of the tyrosine phosphatase, SHP2 (encoded by PTPN11), promotes developmental disorders and several malignancies by varying phosphatase activity. We uncovered that SHP2 is a distinct class of an epigenetic enzyme; upon phosphorylation by the kinase ACK1/TNK2, pSHP2 was escorted by androgen receptor (AR) to chromatin, erasing hitherto unidentified pY54-H3 (phosphorylation of histones H3 at Tyr54) epigenetic marks to trigger a transcriptional program of AR. Noonan Syndrome with Multiple Lentigines (NSML) patients, SHP2 knock-in mice, and ACK1 knockout mice presented dramatic increase in pY54-H3, leading to loss of AR transcriptome. In contrast, prostate tumors with high pSHP2 and pACK1 activity exhibited progressive downregulation of pY54-H3 levels and higher AR expression that correlated with disease severity. Overall, pSHP2/pY54-H3 signaling acts as a sentinel of AR homeostasis, explaining not only growth retardation, genital abnormalities and infertility among NSML patients, but also significant AR upregulation in prostate cancer patients.

GC-MS Combined with Fast GC E-Nose for the Analysis of Volatile Components of Chamomile (Matricaria chamomilla L.).

Chamomile has become one of the world's most popular herbal teas due to its unique properties. Chamomile is widely used in dietary supplements, cosmetics, and herbal products. This study aimed to investigate the volatile aromatic components in chamomile. Two analytical techniques, gas chromatography-mass spectrometry (GC-MS) and an ultra-fast gas chromatography electronic nose, were employed to examine samples from Xinjiang (XJ), Shandong (SD), and Hebei (HB) in China, and imported samples from Germany (GER). The results revealed that all chamomile samples contained specific sesquiterpene compounds, including α-bisabolol, bisabolol oxide, bisabolone oxide, and chamazulene. Additionally, forty potential aroma components were identified by the electronic nose. The primary odor components of chamomile were characterized by fruity and spicy notes. The primary differences in the components of chamomile oil were identified as (E)-ß-farnesene, chamazulene, α-bisabolol oxide B, spathulenol and α-bisabolone oxide A. Significant differences in aroma compounds included geosmin, butanoic acid, 2-butene, norfuraneol, γ-terpinene. This study demonstrates that GC-MS and the ultra-fast gas chromatography electronic nose can preliminarily distinguish chamomile from different areas, providing a method and guidance for the selection of origin and sensory evaluation of chamomile. The current study is limited by the sample size and it provides preliminary conclusions. Future studies with a larger sample size are warranted to further improve these findings.

Liquid Interfacial Gating of Superhydrophobic Plasmonic Metal-Organic Frameworks for Three-in-One Separation, Enrichment, and Recognition in Bacterial Quorum Sensing.

Poor adsorption properties of nonadsorbing targets and competing adsorption of nontargets at a liquid interface always hamper the development of interface sensing techniques. There is a need to fabricate materials that are applicable to various interface assemblies and, meanwhile, could be employed as interfacial gating to improve the performance of interface sensing by separating, enriching, and recognizing targets at the liquid interface. Here, superhydrophobic zeolite imidazole frameworks-8@gold nanoparticles-1H,1H,2H,2H-perfluorodecanethiol (ZIF-8@GNPs-PFDT) with a static water contact angle (WCA) of 155° was constructed via electrostatic self-assembly and surface graft modification. The plasmonic metal-organic framework (PMOF) nanohybrid realized all-purpose self-assembly at air/liquid and liquid/liquid interfaces and also facilely assembled on the surface of liquid droplets, hydrogels, and foams. The self-assembled porous materials displayed the capability for separating, enriching, and recognizing analytes at various oil/water interfaces and thus could be used to adsorb nonadsorbing targets and block the competing adsorption of nontargets. The self-assembled ZIF-8@GNPs-PFDT structures were employed as a three-in-one interfacial gating to endow the excellent surface-enhanced Raman scattering (SERS) sensing capability and has become a promising tool for dye molecular analysis, oil/water separation, organic phase identification, and in situ cultivation and monitoring of bacterial quorum sensing (QS).

Transcriptome and metabolome analysis revealed the dynamic change of bioactive compounds of Fructus Ligustri Lucidi.

BACKGROUND: The Fructus Ligustri Lucidi, the fruit of Ligustrum lucidum, contains a variety of bioactive compounds, such as flavonoids, triterpenoids, and secoiridoids. The proportions of these compounds vary greatly during the different fruit development periods of Fructus Ligustri Lucidi. However, a clear understanding of how the proportions of the compounds and their regulatory biosynthetic mechanisms change across the different fruit development periods of Fructus Ligustri Lucidi is still lacking. RESULTS: In this study, metabolite profiling and transcriptome analysis of six fruit development periods (45 DAF, 75 DAF, 112 DAF, 135 DAF, 170 DAF, and 195 DAF) were performed. Seventy compounds were tentatively identified, of which secoiridoids were the most abundant. Eleven identified compounds were quantified by high performance liquid chromatography. A total of 103,058 unigenes were obtained from six periods of Fructus Ligustri Lucidi. Furthermore, candidate genes involved in triterpenoids, phenylethanols, and oleoside-type secoiridoid biosynthesis were identified and analyzed. The in vitro enzyme activities of nine glycosyltransferases involved in salidroside biosynthesis revealed that they can catalyze trysol and hydroxytyrosol to salidroside and hydroxylsalidroside. CONCLUSIONS: These results provide valuable information to clarify the profile and molecular regulatory mechanisms of metabolite biosynthesis, and also in optimizing the harvest time of this fruit.

Hierarchical Chiral Calcium Silicate Hydrate Films Promote Vascularization for Tendon-to-Bone Healing.

Revascularization after rotator cuff repair is crucial for tendon-to-bone healing. The chirality of materials has been reported to influence their performance in tissue repair. However, data on the use of chiral structures to optimize biomaterials as a revascularization strategy remain scarce. Here, calcium silicate hydrate (CSO) films with hierarchical chirality on the atomic to micrometer scale are developed. Interestingly, levorotatory CSO (L-CSO) films promote the migration and angiogenesis of endothelial cells, whereas dextral and racemic CSO films do not induce the same effects. Molecular analysis demonstrates that L-chirality can be recognized by integrin receptors and leads to the formation of focal adhesion, which activates mechanosensitive ion channel transient receptor potential vanilloid 4 to conduct Ca2+ influx. Consequently, the phosphorylation of serum response factor is biased by Ca2+ influx to promote the vascular endothelial growth factor receptor 2 signaling pathway, resulting in enhanced angiogenesis. After implanted in a rat rotator cuff tear model, L-CSO films strongly enhance vascularization at the enthesis, promoting collagen maturation, increasing bone and fibrocartilage formation, and eventually improving the biomechanical strength. This study reveals the mechanism through which chirality influences angiogenesis in endothelial cells and provides a critical theoretical foundation for the clinical application of chiral biomaterials.

Structurally Tunable Donor-Bridge-Fluorophore Architecture Enables Highly Efficient and Concentration-Independent Narrowband Electroluminescence.

Luminescent materials with narrowband emission have extraordinary significance for developing ultrahigh-definition display. B-N-containing multiple resonance thermally activated delayed fluorescence (MR-TADF) materials are strong contenders. However, their device performances pervasively encounter detrimental aggregation-caused quenching effect that is highly vulnerable to doping concentration, complicating device fabrication. Therefore, constructing highly efficient and concentration-independent MR-TADF emitters is of pragmatic importance for improving device controllability and reproducibility, simplifying manufacturing procedures, and conserving production costs. Here, by systematic arrangement of donor triphenylamine and fluorophore BNCz on distinct bridges, a spatial confinement strategy has been developed with a donor-bridge-fluorophore architecture. Structurally fine modulation and progressive evolution to construct molecular entities with congested steric hindrance effect that can suppress intermolecular interactions without substantially affecting the luminescence tone of fluorophore BNCz, resulting in highly efficient and concentration-independent narrowband emitters; through isomer engineering, two isomers BN-PCz-TPA and TPA-PCz-BN with different crystal stacking patterns are synthesized by altering the connection mode between triphenylamine and BNCz. As a result, BN-PCz-TPA-based device showcases maximum external quantum efficiency (EQE) of 36.3% with narrow full-width at half-maximum of 27 nm at 10 wt% doping concentration. Even at 20 wt% doping concentration, the maximum EQE remains at 32.5% and the emission spectrum is almost unchanged.

Tetraniliprole risk assessment: Unveiling a hidden threat for managing a generalist herbivore.

Insecticide resistance poses a significant challenge in managing generalist herbivores such as the tobacco cutworm (TCW), Spodoptera litura. This study investigates the potential risks associated with using the novel diamide insecticide tetraniliprole to control TCW. A tetraniliprole-resistant strain was developed through twelve generations of laboratory selection, indicating an intermediate risk of resistance development. Field monitoring in China revealed a significant incidence of resistance, particularly in the Nanchang (NC) population (>100-fold). Tetraniliprole showed moderate to high cross-resistance to multiple insecticides and was autosomally inherited with incomplete dominance, controlled by multiple genes, some of which belong to the cytochrome P450 family associated with enhanced detoxification. Life table studies indicated transgenerational hormesis, stimulating TCW female fecundity and increasing population net reproduction rates (R0). These findings suggest a potential for pest resurgence under tetraniliprole use. The integrated risk assessment provides a basis for the sustainable management of TCW using tetraniliprole.

Knockdown of one cytochrome P450 gene CYP6DW4 increases the susceptibility of Bemisia tabaci to dimpropyridaz, a novel pyridazine pyrazolecarboxamide insecticide.

Bemisia tabaci is a formidable insect pest worldwide, and it exhibits significant resistance to various insecticides. Dimpropyridaz is a novel pyridazine pyrazolecarboxamide insecticide used against sucking insect pests, but there is little information regarding its metabolic detoxification in arthropods or cross-resistance with other insecticides. In this study, we found that dimpropyridaz shows no cross-resistance with three other popular insecticides, namely abamectin, cyantraniliprole, and flupyradifurone. After treatment of B. tabaci adults with a high dose of dimpropyridaz, higher cytochrome P450 monooxygenase (P450) activity was detected in the survivors, and the expression of the P450 gene CYP6DW4 was highly induced. Cloning and characterization of the full-length amino acid sequence of CYP6DW4 indicated that it contains conserved domains typical of P450 genes, phylogenetic analysis revealed that it was closely related to a B. tabaci protein, CYP6DW3, known to be involved in detoxification of imidacloprid. Silencing of CYP6DW4 by feeding insects with dsRNA significantly increased the susceptibility of B. tabaci to dimpropyridaz. In addition, homology modeling and molecular docking analyses showed the stable binding of dimpropyridaz to CYP6DW4, with binding free energy of -6.65 kcal/mol. Our findings indicate that CYP6DW4 plays an important role in detoxification of dimpropyridaz and possibly promotes development of resistance in B. tabaci.

Orco mediates olfactory behavior and oviposition in the whitefly Bemisia tabaci.

Chemical signals play a central role in mediating insect feeding and reproductive behavior, and serve as the primary drivers of the insect-plant interactions. The detection of chemical signals, particularly host plant volatiles, relies heavily on the insect's complex olfactory system. The Bemisia tabaci cryptic species complex is a group of globally important whitefly pests of agricultural and ornamental crops that have a wide range of host plants, but the molecular mechanism of their host plant recognition is not yet clear. In this study, the odorant coreceptor gene of the Whitefly MEAM1 cryptic species (BtOrco) was cloned. The coding sequence of BtOrco was 1413 bp in length, with seven transmembrane structural domains, and it was expressed primarily in the heads of both male and female adult whiteflies, rather than in other tissues. Knockdown of BtOrco using transgenic plant-mediated RNAi technology significantly inhibited the foraging behavior of whiteflies. This inhibition was manifested as a reduced percentage of whiteflies responding to the host plant and a prolonged foraging period. Moreover, there was a substantial suppression of egg-laying activity among adult female whiteflies. These results indicate that BtOrco has the potential to be used as a target for the design of novel active compounds for the development of environmentally friendly whitefly control strategies.

Overexpression of CYP6CX4 contributing to field-evolved resistance to flupyradifurone, one novel butenolide insecticide, in Bemisia tabaci from China.

Bemisia tabaci is a formidable insect pest worldwide, and exhibits significant resistance to various insecticides. Flupyradifurone is one novel butenolide insecticide and has emerged as a new weapon against B. tabaci, but field-evolved resistance to this insecticide has become a widespread concern. To unravel the mechanisms of field-evolved flupyradifurone resistance, we conducted a comprehensive investigation into susceptibility of twenty-one field populations within the Beijing-Tianjin-Hebei Region of China. Alarmingly, thirteen of these populations displayed varying degrees of resistance, ranging from low to medium levels, and building upon our prior findings, we meticulously cloned and characterized the CYP6CX4 gene in B. tabaci. Our investigations unequivocally confirmed the association between CYP6CX4 overexpression and flupyradifurone resistance in three of the thirteen resistant strains via RNA interference. To further validate our findings, we introduced CYP6CX4 overexpression into a transgenic Drosophila melanogaster line, resulting in a significant development of resistance to flupyradifurone in D. melanogaster. Additionally, homology modeling and molecular docking analyses showed the stable binding of flupyradifurone to CYP6CX4, with binding free energy of -6.72 kcal mol-1. Collectively, our findings indicate that the induction of CYP6CX4 exerts one important role in detoxification of flupyradifurone, thereby promoting development of resistance in B. tabaci.

High-Efficiency and Narrowband Green Thermally Activated Delayed Fluorescence Organic Light-Emitting Diodes Based on Two Diverse Boron Multi-Resonant Skeletons.

Up to now, highly efficient narrowband thermally activated delayed fluorescence (TADF) molecules constructed by oxygen-bridged boron with an enhancing multiple resonance (MR) effect have been in urgent demand for solid-state lighting and full-color displays. In this work, a novel MR-TADF molecule, BNBO, constructed by the oxygen-bridged boron unit and boron-nitrogen core skeleton as an electron-donating moiety, is successfully designed and synthesized via a facile one-step synthesis. Based on BNBO as an efficient green emitter, the organic light-emitting diode (OLED) shows a sharp emission peak of 508 nm with a full-width at half-maximum (FWHM) of 36 nm and realizes quite high peak efficiency values, including an external quantum efficiency (EQEmax) of 24.3% and a power efficiency (PEmax) of 62.3 lm/W. BNBO possesses the intramolecular charge transfer (ICT) property of donor-acceptor (D-A) materials and multiple resonance characteristics, which provide a simple strategy for narrowband oxygen-boron materials.

In Situ Spatiotemporal SERS Profiling of Bacterial Quorum Sensing by Hierarchical Hydrophobic Plasmonic Arrays in Agar Medium.

A feedback inhibition effect of high autoinducer levels on metabolite secretion in Chromobacterium subtsugae (C. subtsugae) was evidenced by in situ spatiotemporal surface-enhanced Raman spectroscopy (SERS) profiling. The hierarchical hydrophobic plasmonic array in agar medium is structured by oil/water/oil (OL/W/OH) triphasic interfacial self-assembly. The hydrophobic layer acts as a "door curtain" to selectively permit adsorption of a quorum sensing (QS)-regulated fat-soluble metabolite, i.e., violacein (Vio), and significantly blocks nonspecific adsorption of water-soluble proteins, etc. The SERS profiling clearly evidences that the diffusion of N-hexanoyl-l-homoserine lactone (C6-HSL) in agar medium quickly triggers the initial synthesis of Vio in C. subtsugae CV026 but surprisingly inhibits the intrinsic synthesis of Vio in C. subtsugae ATCC31532. The latter negative response might be related to the VioS repressor of ATCC31532, which negatively controls violacein production without influencing the expression of the CviI/R QS system. Moreover, two sender-receiver systems are constructed by separately coculturing CV026 or ATCC31532 with Hafnia alvei H4 that secretes large amounts of C6-HSL. Expectedly, the cocultivation similarly triggers the initial synthesis of Vio in CV026 but seems to have a quite weak negative effect on the intrinsic synthesis in ATCC31532. In fact, the negative regulation in ATCC31532 might be affected by a diffusion-dependent concentration effect. The H4 growth and its secretion of C6-HSL are a slow and continuous process, thereby avoiding the gathering of local high concentrations. Overall, our study put forward an in situ SERS strategy as an alternative to traditional bioluminescent tools for highly sensitively analyzing the spatiotemporal communication and cooperation in live microbial colonies.