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• Three chiral ionic Pt(II) complexes with tridentate chelating ligand and chiral alkyl chains were successfully synthesized, and all the complexes exhibited bright green emission in dilute acetonitrile solution. • The emission wavelength of these complexes could be changed from green emission originated from intrinsic single molecule to the red emission from excimer by regulating the doping ratios in polymethyl methacrylate. • The CPL signals of monochrome devices could be substantially amplified by an order of magnitude by comparison with solution state. Circularly polarized organic light-emitting diodes (CP-OLEDs) have raised increasing interests owing to their potential application in next-generation displays. In this work, by introducing chiral alkyl chain into tridentate chelating ligand 2,6-bis(N -alkylbenzimidazol-2'-yl)benzene, three chiral Pt(II) complexes are successfully designed and synthesized. All the complexes exhibited bright green emission in dilute acetonitrile solution, while strong yellow-orange emission in highly concentrated solution. However, when these complexes are doped into polymer polymethyl methacrylate, the green emission stemmed from the intrinsic single molecule would be changed into red emission from excimer through adjusting the doping levels. More importantly, the CPL signals could be amplified by an order of magnitude in comparison with solution state. Furthermore, the monochrome devices based on these complexes were successfully fabricated, and achieved good device performances with the maximum luminance of up to 1720 cd m−2 and electroluminescence dissymmetry values of around 2.6 × 10−3. These results indicate that such design strategy for Pt(II) complexes with tridentate cyclometalled ligands would be important for the development of high-performance CP-OLEDs. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Polycyclic phenazine-derived donors were designed for constructing TADF emitters. • The orange OLED employing indolophenazine-based emitter achieved high efficiency. • The orange devices displayed extremely low efficiency roll-off. Two new thermally activated delayed fluorescence (TADF) molecules, tBuInPz-BO and InPz-BO , are constructed via connecting novel rigid polycyclic phenazine-derived donors with oxygen-bridged boron acceptor. Both emitters exhibit fast reverse intersystem crossing rates and high photoluminescence quantum yields, owing to the high molecular structural rigidity. As a result, the orange organic light-emitting diode (OLED) fabricated with tBuInPz-BO shows a maximum external quantum efficiency (EQE max) of 22.0% with the electroluminescence peak at 585 nm. Moreover, the device displays extremely low efficiency roll-off. At high luminance of 1000 and 10000 cd/m2, the EQE values still maintain a high level of 20.2% and 14.8%, respectively, achieving state-of-the-art electroluminescence performance among TADF-based orange OLEDs. This work reveals the great potential of the new phenazine-derived donors for constructing highly efficient TADF emitters. [ABSTRACT FROM AUTHOR]

[Display omitted] • Simple construction of three efficient TADF emitters based on spiro-junction. • LUMO extension design inducing enhanced radiative decay. • Efficient OLEDs achieving external quantum efficiency up to 20.4% • Relieved efficiency roll-off of 2.4% at 100 cd m−2. Thermally activated delayed fluorescent (TADF) emitters have shown their unique advantages in attaining efficient organic light emitting diodes (OLEDs). However, the large efficiency roll-off still stands in the way of their further application. In this study, we design and synthesize a series of TADF emitters based on spiro-junction via a LUMO extension strategy to optimize the roll-off and comprehend the structure–property relationship. Spiro-junction ensures all emitters with decent TADF behaviors. SIR-B with proper phenyl conjugation exhibits the fastest radiative decay and efficient reversed intersystem crossing (RISC) process which ensures the fast conversion of both singlet and triplet excitons. Therefore, SIR-B based device achieves the best performance with the maximum external quantum efficiency of 20.4%. Notably, the EQE of 17.6% is maintained at a practical luminance of 1000 cd/m−2, demonstrating a much-relieved roll-off. As comparison, SIR-A and SIR-C separately feature slow radiative decay and RISC resulting in their serious roll-offs. This contribution could provide a guidance to develop efficient OLEDs with small efficiency roll-off. [ABSTRACT FROM AUTHOR]

• The energy centrobaric correction method is faster and provides less error than the popular PSM method in simulation. For the first time, these two algorithms are compared in simulation. • Our OCT system can provide precise topography result both on a nanometer scale and on a millimeter scale. • The optical point scanning system can better distinguish the lateral feature of samples than the camera-and-lens-based imaging system, in general. • Compared to the commercially available white light interferometer, our system can provide better lateral structure features, and the axial measurement range is flexible to adjust. A spectral-domain optical coherence tomography (SD-OCT) system with 1555 nm center wavelength is tested for stability and accuracy from the micron level to the sub-micron level. The energy centrobaric correction method is used to extract the sub-axial-resolution information as the optical path difference, i.e., the topographic height. We compared the used algorithm with the widely applied phase slope method. The stability of a point scanning OCT system in Michelson style is experimentally compared with that of a system in Fizeau style. Several simple and complicated samples are measured and compared. Finally, we compare the topographic performance of the OCT system with a commercial confocal microscope and white-light interferometer (WLI). [ABSTRACT FROM AUTHOR]

The scarcity of highly conductive materials with solution-processable ability and the contradictory relationship between conductivity (σ) and Seebeck coefficient (S), have greatly limited the development of thermoelectric (TE) materials. To address these challenges, we propose a novel strategy from the following two aspects: 1) Highly conductive materials with solution-processable ability are achieved by simply combining platinum-based complexes with Single-walled carbon nanotubes (SWCNTs). Among them, SWCNT/Pt-4 manifests the highest σ (4166.3 S cm−1), which is among the highest for p-type SWCNT-based TE materials; 2) The TE material with high S is applied to the above system to overcome the restrictive relationship between S and σ. The optimized three composites display remarkably higher power factor (PF) than those of either two hybrids at room temperature, and the highest PF is achieved by SWCNT/(Ge 0.87 Pb 0.13 Te) 0.95 (Bi 2 Te 3) 0.05 /PtCl 4 (471.8 μW m−1 K−2) at 420 K. This strategy simultaneously improves the PF of SWCNTs by innovatively introducing a three-phase system in the composites. Our work opens up new material options for TE applications and provides a robust pathway to the development of high-performance TE materials. [Display omitted] • Both the platinum and ligands played a dominate role in enhancing the σ of SWCNTs. • SWCNT/Pt-4 manifested the highest σ with the value of 4166.3 S cm−1. • The combinations can induce a synergistic effect on the TE performance. • The highest PF (471.8 μW m−1 K−2) was achieved by three-phase composites at 420 K. [ABSTRACT FROM AUTHOR]

Fluorescent materials taking both advantages of evaporation and solution processes are urgently explored for the development of efficient and simplified organic light-emitting diodes (OLEDs). Furthermore, it is another huge challenge for such materials to achieve excellent electroluminescence performances in non-doped OLEDs. Herein, two new emitters, named as PyB-DPAC and PyB-DMAC with 4-benzoylpyridine moiety as the electron acceptor and 9,9-diphenyl-9,10-dihydroacridine or 9,9-dimethyl-9,10-dihydroacridine as the electron donor were synthesized and explored. Both emitters exhibit distinct TADF character, typical AIE feature and relatively high photoluminescence quantum yields. Accordingly, we demonstrated efficient non-doped vacuum-deposited OLED based on the PyB-DPAC with a maximum external quantum efficiency (EQE) up to 9.7%, and meanwhile an extremely low efficiency roll-off of 1.7% at a high brightness of 1000 cd m−2. In addition, an impressive EQE of 11.1% can be realized from the solution-processed non-doped devices with the using of PyB-DPAC emitter. These affirmative results manifest that TADF emitters incorporate with the benzoylpyridine acceptor enabling a promising molecular design strategy in adapt to the non-doped evaporation- and solution-processed highly efficient OLEDs. Image 1 • Benzoylpyridine is used as acceptor to construct two new TADF emitters. • Both emitters simultaneously exhibit distinct TADF character and typical AIE feature. • The non-doped evaporation-/ solution-process devices based on PyB-DPAC exhibited maximum EQE of 9.7% / 11.1%, respectively. • This work would be instructive in the rational molecular design of efficient non-doped solution-process emitters. [ABSTRACT FROM AUTHOR]

Background: Peanut allergy is among the most severe and common food allergies. The diagnosis has a significant impact on the quality of life for patients and their families. An effective management approach depends on accurate, safe, and easily implementable diagnostic methods. We previously developed a cell-based assay using Hoxb8 mast cells (Hoxb8 MCs) aimed at improving clinical allergy diagnosis. In this study, we assessed its diagnostic performance by measuring blinded sera from a prospectively enrolled and pre-validated peanut allergy cohort., Methods: Hoxb8 MCs were passively sensitized with sera from peanut-allergic and peanut tolerant children and adolescents (n = 112). Degranulation of Hoxb8 MCs was quantified upon stimulation with dose-titrated peanut extract by means of flow cytometry, using CD107a as activation marker. The results from the Hoxb8 mast cell activation test (Hoxb8 MAT) were compared to established diagnostic assays such as the skin prick test (SPT), specific IgE (sIgE) levels, and the basophil activation test (BAT). Additionally, serum samples from BAT nonresponders were assessed with the Hoxb8 MAT., Results: Hoxb8 MAT displayed a robust dose-dependent activation to peanut extract, with a cutoff value of ≤5.2% CD107a positive cells. The diagnostic accuracy was highest at allergen concentrations ≥100 ng/mL, with an area under the receiver operating characteristic curve (AUROC) of 0.97, 93% sensitivity, and 96% specificity, outperforming traditional SPT and sIgE tests. When compared to BAT, Hoxb8 MAT exhibited comparable diagnostic efficacy. Moreover, sera from BAT nonresponders were accurately classified into allergics and nonallergics by the Hoxb8 MAT., Conclusions: The Hoxb8 MAT demonstrated a very good diagnostic precision in patients prospectively assessed for peanut allergy comparable to the fresh whole blood-based BAT. Additionally, it demonstrated its value for accurate classification of BAT nonresponders into allergic and nonallergic individuals. Further investigations into its utility in the routine clinical setting are warranted., (© 2024 The Author(s). Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)

We herein delve into the corrosion dynamics of UG1 in high-temperature water, employing thermal acceleration to expedite reactions. Corrosion-induced changes in spectral properties, optical constants, and morphology are analyzed. The results reveal a phosphorus-poor layer near the surface that affects transmittance, refractive index, and extinction coefficient, with corrosion rates following a parabolic model. This study provides crucial insights for protecting UG1 in humid environments and emphasizes the importance of implementing protective measures against phosphorus diffusion., Competing Interests: The authors declare that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

The synergistic integration of a fine-tuned chiral donor with a hybrid long/short-range charge-transfer mechanism offers an accessible pathway to construct highly efficient circularly polarized emitters. Consequently, a notable dissymmetry factor of 1.6 × 10 -3 , concomitantly with a record-setting maximum external quantum efficiency of 37.4%, is synchronously realized within a single embodiment.

Helicenes exhibit substantial potential as circularly polarized luminescence (CPL) active molecules. However, their application in circularly polarized organic light-emitting diodes (CP-OLEDs) is typically hindered by the challenge of integrating both high color purity and efficient triplet-harvesting capability, particularly in the blue spectral region. Herein, a series of hetero[6]helicene-based emitters that is strategically engineered through the helical extension of a deep-blue double-boron-based multiple resonance thermally activated delayed fluorescence (MR-TADF) motif, is introduced. Importantly, the helical extension does not cause apparent structural deformation or perturb frontier molecular orbitals; thus, preserving the deep-blue emission and MR-TADF characteristics of the parent molecule. This approach also leads to reduced reorganization energy, resulting in emitters with narrower linewidth and higher photoluminescence quantum yield. Further, the helical motif enhances the racemization barrier and leads to improved CPL performance with luminescence dissymmetry factor values up to 1.5 × 10 -3 . Exploiting these merits, devices incorporating the chiral dopants demonstrate deep-blue emission within the Broadcast Service Television 2020 color-gamut range, record external quantum efficiencies (EQEs) up to 29.3%, and have distinctive circularly polarized electroluminescence (CPEL) signals. Overall, the authors' findings underscore the helical extension as a promising strategy for designing narrowband chiroptical materials and advancing high-definition displays., (© 2023 Wiley-VCH GmbH.)

Supramolecular polymers based on chiral macrocycles have attracted increasing attention in the field of circularly polarized luminescence (CPL) owing to their unique properties. However, the construction of macrocyclic supramolecular polymers with highly efficient CPL properties in aggregate states still remains challenging. Herein, w e constructed a class of macrocycle-based coordination polymers by combining the planar chiral properties of pillar[5]arene with the excellent fluorescence properties of aggregation-induced emission luminogens. The formation of polymers enhances both the fluorescence and chiral properties, resulting in chiral supramolecular polymers with remarkable CPL properties. Increasing the aggregation degree of the polymers can further improve their CPL properties, as evidenced by a 21-fold increase in the dissymmetry factor and an over 25-fold increase in the fluorescence quantum yield in the aggregate state compared to the solution state. Such a synergistic effect of polymerization- and aggregation-enhanced CPL can be explained by the restriction of intramolecular motions and aggregation-induced conformation confinement. This work provides a promising method for developing highly efficient CPL supramolecular polymers., (© 2023 The Authors. Advanced Science published by Wiley-VCH GmbH.)

The Manasi region is located in an arid and semi-arid region with fragile ecology and scarce resources. The land use change prediction is important for the management and optimization of land resources. We utilized Sankey diagram, dynamic degree of land use, and landscape indices to explore the temporal and spatial variation of land use and integrated the LSTM and MLP algorithms to predict land use prediction. The MLP-LSTM prediction model retains the spatiotemporal information of land use data to the greatest extent and extracts the spatiotemporal variation characteristics of each grid through a training set. Results showed that (1) from 1990 to 2020, cropland, tree cover, water bodies, and urban areas in the Manasi region increased by 855.3465 km 2 , 271.7136 km 2 , 40.0104 km 2 , and 109.2483 km 2 , respectively, whereas grassland and bare land decreased by 677.7243 km 2 and 598.5945 km 2 , respectively; (2) Kappa coefficients reflect the accuracy of the mode's predictions in terms of quantity. The Kappa coefficients of the land use data predicted by the MLP-LSTM, MLP-ANN, LR, and CA-Markov models were calculated to be 95.58%, 93.36%, 89.48%, and 85.35%, respectively. It can be found that the MLP-LSTM and MLP-ANN models obtain higher accuracy in most levels, while the CA-Markov model has the lowest accuracy. (3) The landscape indices can reflect the spatial configuration characteristics of landscape (land use types), and evaluating the prediction results of land use models using landscape indices can reflect the prediction accuracy of the models in terms of spatial features. The results indicate that the model predicted by MLP-LSTM model conforms to the development trend of land use from 1990 to 2020 in terms of spatial features. This gives a basis for the study of the Manasi region to formulate relevant land use development and rationally allocate land resources., (© 2023. The Author(s).)

Most multi-resonance (MR) induced thermally activated delayed fluorescence (TADF) emitters generally exhibit strong aggregation and relatively worse solubility due to their rigid and planar molecule structures, which is highly undesirable for solution-processible devices. Herein, a simple but feasible approach for solution-processible small-molecule MR-TADF emitters is developed by incorporating two MR-TADF units onto carbazole bridge bearing long alkyl chains. The obtained emitters demonstrate supreme film-forming capability and narrowband emissions with full-width at half-maximums (FWHMs) of 22 nm. The resulting solution-processed narrowband electroluminescent devices achieve maximum external quantum efficiency of 27.1 %, which represents the highest efficiency among the solution-processed OLEDs based on MR-TADF emitters. This simple approach reveals great potential of developing solution-processible emitters for rigid and planar molecular structures., (© 2023 Wiley-VCH GmbH.)

Background: Food allergy affects up to 10% of the pediatric population. Despite ongoing efforts, treatment options remain limited. Novel models of food allergy are needed to study response patterns downstream of IgE-crosslinking and evaluate drugs modifying acute events. Here, we report a novel human ex vivo model that displays acute, allergen-specific, IgE-mediated smooth muscle contractions using precision cut intestinal slices (PCIS)., Methods: PCIS were generated using gut tissue samples from children who underwent clinically indicated surgery. Viability and metabolic activity were assessed from 0 to 24 h. Distribution of relevant cell subsets was confirmed using single nucleus RNA sequencing. PCIS were passively sensitized using plasma from peanut allergic donors or peanut-sensitized non-allergic donors, and exposed to various stimuli including serotonin, histamine, FcɛRI-crosslinker, and food allergens. Smooth muscle contractions and mediator release functioned as readouts. A novel program designed to measure contractions was developed to quantify responses. The ability to demonstrate the impact of antihistamines and immunomodulation from peanut oral immunotherapy (OIT) was assessed., Results: PCIS viability was maintained for 24 h. Cellular distribution confirmed the presence of key cell subsets including mast cells. The video analysis tool reliably quantified responses to different stimulatory conditions. Smooth muscle contractions were allergen-specific and reflected the clinical phenotype of the plasma donor. Tryptase measurement confirmed IgE-dependent mast cell-derived mediator release. Antihistamines suppressed histamine-induced contraction and plasma from successful peanut OIT suppressed peanut-specific PCIS contraction., Conclusion: PCIS represent a novel human tissue-based model to study acute, IgE-mediated food allergy and pharmaceutical impacts on allergic responses in the gut., (© 2022 The Authors. Allergy published by European Academy of Allergy and Clinical Immunology and John Wiley & Sons Ltd.)

Multiresonance thermal activated delayed fluorescence (MR-TADF) materials with an efficient spin-flip transition between singlet and triplet excited states remain demanding. Herein, we report an MR-TADF compound ( BN-Se ) simultaneously possessing efficient (reverse) intersystem crossing (ISC/RISC), fast radiative decay, close-to-unity quantum yield, and narrowband emission by embedding a single selenium atom into a common 4,4'-diazaborin framework. Benefitting from the high RISC efficiency accelerated by the heavy-atom effect, organic light-emitting diodes (OLEDs) based on BN-Se manifest excellent performance with an external quantum efficiency of up to 32.6% and an ultralow efficiency roll-off of 1.3% at 1000 cd m -2 . Furthermore, the high ISC efficiency and small inherent energy loss also render BN-Se a superior photosensitizer to realize the first example of visible (λ ex > 450 nm)-to-UV (λ em < 350 nm) triplet-triplet annihilation upconversion, with a high efficiency (21.4%) and an extremely low threshold intensity (1.3 mW cm -2 ). This work not only aids in designing advanced pure organic molecules with fast exciton dynamics but also highlights the value of MR-TADF compounds beyond OLED applications.

Background: Lung adenocarcinoma (LUAD) is one of the most prevalent human cancers worldwide. The homeobox-B (HOXB) gene cluster has been reported to contribute to cancer development. Nevertheless, the expression status, clinical significance and biological role of HOXB genes in LUAD remain largely unclear., Methods and Results: This study comprehensively investigated the transcriptional levels and prognostic values of the HOXB genes in LUAD based on The Cancer Genome Atlas (TCGA) database. Flow cytometry, CCK-8, and Transwell assays were used for detecting apoptosis, proliferation, and migration, respectively. We discovered that eight members of the HOXB cluster genes (HOXB2, HOXB3, HOXB4, HOXB6, HOXB7, HOXB8, HOXB9, and HOXB13) were dysregulated in LUAD tumor tissues. Increased expression of HOXB3, HOXB6, HOXB7, HOXB8, or HOXB9 was independently associated with unsatisfactory overall survival (OS) in LUAD patients. In addition, a high level of HOXB3 also predicted poor patient relapse-free survival (RFS), suggesting that HOXB3 may play a vital role in the progression of LUAD compared to other members of the HOXB cluster. Additionally, further analysis by TIMER and TISIDB algorithms revealed that HOXB3 was positively correlated with a panel of immune checkpoint molecules (ICMs), tumor-infiltrating lymphocytes (TILs), and tumor immune regulators (TIRs). Gene enrichment analysis based on KEGG showed that HOXB3 was closely associated with multiple tumor-related biological processes and signaling pathways. Functionally, the in vitro experiments revealed that depletion of HOXB3 significantly alleviated the resistance of LUAD cells to apoptosis, and suppressed cell proliferation and migration., Conclusion: Our study suggests that HOXB3 may play an oncogenic role in LUAD and correlate with tumor immunity., (© 2021. The Author(s), under exclusive licence to Springer Nature B.V.)

Competing Interests: Competing interests: None declared.