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1.
Nat Commun ; 15(1): 4394, 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38782957

RESUMO

Manipulating dynamic behaviours of charge carriers and excitons in organic light-emitting diodes (OLEDs) is essential to simultaneously achieve high colour purity and superior operational lifetime. In this work, a comprehensive transient electroluminescence investigation reveals that incorporating a thermally activated delayed fluorescence assistant molecule with a deep lowest unoccupied molecular orbital into a bipolar host matrix effectively traps the injected electrons. Meanwhile, the behaviours of hole injection and transport are still dominantly governed by host molecules. Thus, the recombination zone notably shifts toward the interface between the emissive layer (EML) and the electron-transporting layer (ETL). To mitigate the interfacial carrier accumulation and exciton quenching, this bipolar host matrix could serve as a non-barrier functional spacer between EML/ETL, enabling the distribution of recombination zone away from this interface. Consequently, the optimized OLED exhibits a low driving voltage, promising device stability (95% of the initial luminance of 1000 cd m-2, LT95 > 430 h), and a high Commission Internationale de L'Éclairage y coordinate of 0.69. This indicates that managing the excitons through rational energy level alignment holds the potential for simultaneously satisfying Rec.2020 standard and achieving commercial-level stability.

2.
World J Gastrointest Oncol ; 16(5): 1925-1946, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38764837

RESUMO

BACKGROUND: The treatment of gastric cancer (GC) has caused an enormous social burden worldwide. Accumulating studies have reported that N6-methyladenosine (m6A) is closely related to tumor progression. METTL5 is a m6A methyltransferase that plays a pivotal role in maintaining the metabolic stability of cells. However, its aberrant regulation in GC has not been fully elucidated. AIM: To excavate the role of METTL5 in the development of GC. METHODS: METTL5 expression and clinicopathological characteristics were analyzed via The Cancer Genome Atlas dataset and further verified via immunohistochemistry, western blotting and real-time quantitative polymerase chain reaction in tissue microarrays and clinical samples. The tumor-promoting effect of METTL5 on HGC-27 and AGS cells was explored in vitro by Cell Counting Kit-8 assays, colony formation assays, scratch healing assays, transwell assays and flow cytometry. The tumor-promoting role of METTL5 in vivo was evaluated in a xenograft tumor model. The EpiQuik m6A RNA Methylation Quantification Kit was used for m6A quantification. Next, liquid chromatography-mass spectrometry was used to evaluate the association between METTL5 and sphingomyelin metabolism, which was confirmed by Enzyme-linked immunosorbent assay and rescue tests. In addition, we investigated whether METTL5 affects the sensitivity of GC cells to cisplatin via colony formation and transwell experiments. RESULTS: Our research revealed substantial upregulation of METTL5, which suggested a poor prognosis of GC patients. Increased METTL5 expression indicated distant lymph node metastasis, advanced cancer stage and pathological grade. An increased level of METTL5 correlated with a high degree of m6A methylation. METTL5 markedly promotes the proliferation, migration, and invasion of GC cells in vitro. METTL5 also promotes the growth of GC in animal models. METTL5 knockdown resulted in significant changes in sphingomyelin metabolism, which implies that METTL5 may impact the development of GC via sphingomyelin metabolism. In addition, high METTL5 expression led to cisplatin resistance. CONCLUSION: METTL5 was found to be an oncogenic driver of GC and may be a new target for therapy since it facilitates GC carcinogenesis through sphingomyelin metabolism and cisplatin resistance.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38768497

RESUMO

Developing thermally activated delayed fluorescence (TADF) near-infrared (NIR) organic light-emitting diodes (OLEDs) based on nondoped emitting layers is intriguing yet challenging, limited by low exciton utilization and notorious concentration quenching. Herein, a facile strategy is proposed to address this issue by incorporating an internal host component onto a traditional donor (D)-acceptor (A)-type red TADF molecule. A proof-of-concept emitter with an internal host is accordingly developed as well as a control one without an internal host. In the case of their monomer states, both emitters exhibit similar emission spectra due to their identical D-A pairs. However, under nondoped conditions, significant improvement in exciton utilization and quenching-resistant features are observed for the molecule with the internal host. The corresponding nondoped OLED yielded a maximum external quantum efficiency of 2.4%, with NIR emission peaking at 765 nm, which was a nearly 10-fold improvement relative to the efficiency based on the control molecule without an internal host. To the best of our knowledge, this result is on par with those of state-of-the art nondoped NIR TADF OLEDs in a similar emission region. These results offer a feasible pathway for the design and development of high-efficiency NIR nondoped OLEDs.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38547523

RESUMO

ABSTRACT: Sepsis-induced myocardial dysfunction (SIMD) commonly occurs in individuals with sepsis and is a severe complication with high morbidity and mortality rates. The current study aimed to investigate the effects and potential mechanisms of the natural steroidal sapogenin ruscogenin (RUS) against lipopolysaccharide (LPS)-induced myocardial injury in septic mice. We found that RUS effectively alleviated myocardial pathological damage, normalized cardiac function, and increased survival in septic mice. RNA sequencing (RNA-seq) demonstrated that RUS administration significantly inhibited the activation of the NOD-like receptor signaling pathway in the myocardial tissues of septic mice. Subsequent experiments further confirmed that RUS suppressed myocardial inflammation and pyroptosis during sepsis. Additionally, cultured HL-1 cardiomyocytes were challenged with LPS, and we observed that RUS could protect these cells against LPS-induced cytotoxicity by suppressing inflammation and pyroptosis. Notably, both the in vivo and in vitro findings indicated that RUS inhibited NLRP3 upregulation in cardiomyocytes stimulated with LPS. As expected, knockdown of NLRP3 blocked the LPS-induced activation of inflammation and pyroptosis in HL-1 cells. Furthermore, the cardioprotective effects of RUS on HL-1 cells under LPS stimulation were abolished by the novel NLRP3 agonist BMS-986299. Taken together, our results suggest that RUS can alleviate myocardial injury during sepsis, at least in part by suppressing NLRP3-mediated inflammation and pyroptosis, highlighting the potential of this molecule as a promising candidate for SIMD therapy.

5.
Curr Med Imaging ; 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38529651

RESUMO

Objective: To explore the application value of a combined model based on multi-parameter MRI radiomics and clinical features in preoperative prediction of lymphatic vascular space invasion (LVSI) in endometrial carcinoma (EC). METHODS: This retrospective study collected the clinicopathological and imaging data of 218 patients with EC in Yuncheng Central Hospital from March 2018 to May 2022. The patients were randomly divided into training group (n=152) and validation group (n= 66) according to the ratio of 7: 3. Based on the ADC, CE-sag, CE-tra, DWI, T2WI-sag-fs, T2WI-tra sequence images of each patient, the region of interest was manually segmented and the features were extracted. The four-step dimensionality reduction method based on max-relevance and min-redundancy (MRMR) and least absolute shrinkage and selection operator (LASSO) regression was used for feature selection and radiomics model construction. Independent predictors of clinicopathological features were screened by multivariate logistic regression analysis. The imaging model based on ADC, CE-sag, CE-tra, DWI, T2WI-sag-fs, T2WI-tra single sequence and combined sequence and the fusion model with clinicopathological features were constructed, and the nomogram was made. ROC curve, correction curve and decision analysis curve were used to evaluate the efficacy and clinical benefits of the nomogram. RESULTS: There was no significant difference in general clinical data between the training and validation groups (P > 0.05). After screening the extracted features, 16 radiomics features were obtained, which were all related to LVSI in EC patients (P < 0.05). The area under the ROC curve (AUC) of the six independent sequence radiomics models in the training group was 0.807, 0.794, 0.826, 0.794, 0.828, 0.824, respectively. The AUC corresponding to the radiomics model constructed by the combined sequence was 0.884, and the diagnostic efficiency was the best, which was verified in the validation group. The AUC of the nomogram constructed by the combined radiomics model and age maximum tumor diameter(MTD), lymph node enlargement (LNE) in the training group and the validation group were 0.914 and 0.912, respectively. The correction curve shows that the nomogram has good correction performance. The decision curve suggests that taking radiomics nomogram to predict LVSI net benefit when the risk threshold is > 10% is better than considering all patients as LVSI+ or LVSI-. CONCLUSION: The combined model based on multi-parametric MRI radiomics features and clinical features has good predictive value for LVSI status in EC patients.

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6.
Small ; : e2312098, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38461523

RESUMO

Double-borylated multiple-resonance (MR) skeletons are promising templates for high performance, while the chemical design space is relatively limited. Peripheral segments are often used to decorate/fuse MR skeletons and modulate the photophysics but they can also cause unwanted spectral broadening. Herein, a narrowband MR emitter ICzDBA by fusing an MR-featured donor segment indolocarbazole into a double-borylated MR skeleton is developed. In ICzDBA, the nitrogen atom located away from the core benzene ring can also contribute to the generation of the overall MR-featured distribution through the long-range conjugation effect, along with the other boron/nitrogen atoms on the phenyl center. Thus, ICzDBA in toluene displays a narrowband emission peaking at 507 nm with a full width at half maximum of merely 20 nm (0.09 eV). Moreover, organic light-emitting diode devices using ICzDBA emitter exhibit ultrapure green emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.27, 0.70) and a high external quantum efficiency of 32.5%. These results manifest the importance of MR characters of peripheral decorations/fusions in preserving the narrowband features of MR skeletons, which provides a solution for further expanding MR structures with well-maintained narrowband characters.

7.
Telemed J E Health ; 30(5): 1425-1435, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38346325

RESUMO

Background: Children with special health care needs (CSHCN) require long-term and ongoing rehabilitation interventions supporting their development. Telerehabilitation can provide continuous rehabilitation services for CSHCN. However, few studies have explored the intention of CSHCN and their caregivers to use telerehabilitation and its impact on them. Objective: The objective of this study was to identify factors that influence the intention to use telerehabilitation among CSHCN and their caregivers. Methods: This study was a cross-sectional study. Based on the unified theory of acceptance and use of technology, extended with additional predictors (trust and perceived risk [PR]), this study developed a research model and proposed 10 hypotheses. A structured questionnaire was distributed to 176 caregivers. Data were analyzed and research hypotheses were tested using partial least squares structural equation modeling to better understand the factors influencing the use of telerehabilitation. Results: A total of 164 valid questionnaires were collected. CSHCN and their caregivers were overall satisfied with this telerehabilitation medical service. The results of the structural model analysis indicated that social influence (SI), facilitating conditions (FC), and trust had significant effects on behavioral intention (BI) to use telerehabilitation, while the paths between performance expectancy (PE), effort expectancy (EE), and PR and BI were not significant. PE, EE, and SI had a significant effect on trust. Moreover, EE and SI had indirect effects on BI, with trust as the mediator. Conclusions: The results indicated that SI, FC, and trust are significant factors influencing CSHCN and their caregivers' use of telerehabilitation. Trust is also an important mediator for the intention and highly influenced by PE, EE, and SI.


Assuntos
Cuidadores , Crianças com Deficiência , Intenção , Telerreabilitação , Humanos , Estudos Transversais , Masculino , Feminino , Telerreabilitação/métodos , Criança , Crianças com Deficiência/reabilitação , Cuidadores/psicologia , Adolescente , Adulto , Confiança , Pré-Escolar , Inquéritos e Questionários , Pessoa de Meia-Idade
8.
J Org Chem ; 89(4): 2351-2363, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38301039

RESUMO

An effective and stereoselective synthesis of halogenated (E)-4-methylenechromanes with a sulfonyl group was developed via the copper-catalyzed sulfonylative annulation/halogenation of 1,7-enynes, in which sodium sulfinates were used as the sulfonyl reagents and tetrabutylammonium halide provided the halogen sources. The formed alkenyl C-X bonds were valuable and can efficiently undergo the subsequent hydrolysis, alkenylation, alkynylation, arylation, alkylthiolation, and alkoxylation to furnish a series of highly functionalized 4-methylenechromanes.

9.
Nat Commun ; 15(1): 731, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38272899

RESUMO

Organic light-emitting diodes (OLEDs) exploiting simple binary emissive layers (EMLs) blending only emitters and hosts have natural advantages in low-cost commercialization. However, previously reported OLEDs based on binary EMLs hardly simultaneously achieved desired comprehensive performances, e.g., high efficiency, low efficiency roll-off, narrow emission bands, and high operation stability. Here, we report a molecular-design strategy. Such a strategy leads to a fast reverse intersystem crossing rate in our designed emitter h-BNCO-1 of 1.79×105 s-1. An OLED exploiting a binary EML with h-BNCO-1 achieves ultrapure emission, a maximum external quantum efficiency of over 40% and a mild roll-off of 14% at 1000 cd·m-2. Moreover, h-BNCO-1 also exhibits promising operational stability in an alternative OLED exploiting a compact binary EML (the lifetime reaching 95% of the initial luminance at 1000 cd m-2 is ~ 137 h). Here, our work has thus provided a molecular-design strategy for OLEDs with promising comprehensive performance.

10.
Chem Commun (Camb) ; 60(18): 2489-2492, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38196344

RESUMO

Herein, we report a fluorene-bridged double carbonyl/amine-based MR TADF emitter DDiKTa-F, formed by locking the conformation of the previously reported compound DDiKTa. Using this strategy, DDiKTa-F exhibited narrower, brighter, and red-shifted emission. The OLEDs with DDiKTa-F emitted at 493 nm and showed an EQEmax of 15.3% with an efficiency roll-off of 35% at 100 cd m-2.

11.
Adv Mater ; 36(8): e2307725, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37792472

RESUMO

Realizing efficient red/near-infrared (NIR) electroluminescence (EL) by precisely modulating molecular aggregations of thermally activated delayed fluorescence (TADF) emitters is an attractive pathway, yet the molecular designs are elusive. Here, a new approach is proposed to manage molecular aggregation via a mild-twist acceptor-donor-acceptor (A-D-A)-type molecular design. A proof-of-concept TADF molecule, QCN-PhSAC-QCN, is developed that furnishes a fast radiative rate and obvious aggregation-induced emission feature. Its emission bands can be facilely shifted from intrinsic yellow to the red/NIR region via fine-tuning doping levels and molecular aggregates while maintaining elegant photoluminescence quantum yields benefiting from suppressed exciton annihilation processes. As a result, a QCN-PhSAC-QCN-based organic light-emitting diode (OLED) exhibits a record-setting external quantum efficiency (EQE) of 39.1% at a doping ratio of 10 wt.%, peaking at 620 nm. Moreover, its nondoped NIR OLED affords a champion EQE of 14.3% at 711 nm and retains outstanding EQEs of 5.40% and 2.35% at current densities of 10 and 100 mA cm-2 , respectively, which are the highest values among all NIR-TADF OLEDs at similar density levels. This work validates the feasibility of such mild-twist A-D-A-type molecular design for precisely controlling molecular aggregation while maintaining high efficiency, thus providing a promising pathway for high-performance red/NIR TADF OLEDs.

12.
Opt Express ; 31(23): 37763-37777, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017899

RESUMO

In recent years, deep learning (DL) has demonstrated significant potential in the inverse design of metasurfaces, and the generation of metasurfaces with customized transmission characteristics of frequency band remains a challenging and underexplored area. In this study, we propose a DL-assisted method for the inverse design of transmissive metasurfaces. The method consists of a generative adversarial network (GAN)-based graph generator, an electromagnetic response predictor, and a genetic algorithm optimizer. By integrating these components, we can obtain customized metasurfaces with desired transmission characteristics of frequency band. We demonstrate the effectiveness of the proposed method through examples of inverse-designed three-layer cascaded transmissive metasurfaces with wideband, dual-band, and stopband responses in the 8∼12 GHz frequency range. Specifically, we realize three different types of dual-band metasurfaces, namely double-wide, front-wide and rear-narrow, and front-narrow and rear-wide configurations. Additionally, we analyze the accuracy and reliability of the inverse design method by employing data from the training dataset, self-defined objectives, and bandwidth-reduced target responses scaled from the wideband type as design inputs. Quantitative evaluation is performed using metrics such as mean absolute error and average precision. The proposed method successfully achieves the desired effect as intended.

13.
Nanomicro Lett ; 16(1): 21, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37982963

RESUMO

Massive efforts have been concentrated on the advance of eminent near-infrared (NIR) photothermal materials (PTMs) in the NIR-II window (1000-1700 nm), especially organic PTMs because of their intrinsic biological safety compared with inorganic PTMs. However, so far, only a few NIR-II-responsive organic PTMs was explored, and their photothermal conversion efficiencies (PCEs) still remain relatively low. Herein, donor-acceptor conjugated diradical polymers with open-shell characteristics are explored for synergistically photothermal immunotherapy of metastatic tumors in the NIR-II window. By employing side-chain regulation, the conjugated diradical polymer TTB-2 with obvious NIR-II absorption was developed, and its nanoparticles realize a record-breaking PCE of 87.7% upon NIR-II light illustration. In vitro and in vivo experiments demonstrate that TTB-2 nanoparticles show good tumor photoablation with navigation of photoacoustic imaging in the NIR-II window, without any side-effect. Moreover, by combining with PD-1 antibody, the pulmonary metastasis of breast cancer is high-effectively prevented by the efficient photo-immunity effect. Thus, this study explores superior PTMs for cancer metastasis theranostics in the NIR-II window, offering a new horizon in developing radical-characteristic NIR-II photothermal materials.

14.
J Health Popul Nutr ; 42(1): 115, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37891631

RESUMO

OBJECTIVE: To explore the effect of a health (E)-coach chronic disease management model on the rehabilitation behaviour management of patients with arteriosclerosis obliterans (ASO). METHODS: The E-coach chronic disease management model was constructed based on a literature review and expert interviews. The effect of the E-coach model on patients with ASO during hospitalisation was analysed by comparing the compliance rates of blood glucose control, blood pressure control, drug compliance, ankle-brachial index, 6-min walking test (6MWT) and pain-free walking distance (PFWD) scores between the E-coach and control groups. RESULTS: In total, 212 patients with ASO were included in this study. After the intervention, the blood pressure compliance rate (44.8% vs. 65.7%) and blood glucose compliance rate (48.6% vs. 66.8%) were higher in the E-coach group than in the control group (p < 0.05). After intervention, compared with the control group, the patients in the E-coach group had better drug compliance (6.8 ± 1.9 vs. 7.9 ± 1.0), and the difference was statistically significant (p < 0.05). The scores for the 6MWT (329.19 ± 5.58 vs. 353.00 ± 9.76; 412.65 ± 12.59 vs. 499.16 ± 18.43) and PFWD (219.15 ± 11.96 vs. 225.36 ± 16.13; 331.62 ± 51.36 vs. 369.42 ± 75.71) tests were significantly higher in the E-coach group than in the control group at 1 and 6 months after intervention (p < 0.05). CONCLUSION: The E-coach chronic disease management model can effectively improve the control rates of blood glucose and blood pressure and the behaviour management of patients with ASO and is thus worthy of clinical reference.


Assuntos
Arteriosclerose Obliterante , Humanos , Arteriosclerose Obliterante/terapia , Glicemia , Cooperação do Paciente , Gerenciamento Clínico
15.
World J Pediatr ; 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770810

RESUMO

BACKGROUND: This study aimed to identify survival risk factors in Chinese children with hepatoblastoma (HB) and assess the effectiveness of the new treatment protocol proposed by the Chinese Children's Cancer Group (CCCG) in 2016. METHODS: A multicenter, prospective study that included 399 patients with HB from January 2015 to June 2020 was conducted. Patient demographics, treatment protocols, and other related information were collected. Cox regression models and Kaplan-Meier curve methods were used. RESULTS: The 4-year event-free survival (EFS) and overall survival (OS) were 76.9 and 93.5%, respectively. The 4-year EFS rates for the very-low-risk, low-risk, intermediate-risk, and high-risk groups were 100%, 91.6%, 81.7%, and 51.0%, respectively. The 4-year OS was 100%, 97.3%, 94.4%, and 86.8%, respectively. Cox regression analysis found that age, tumor rupture (R +), and extrahepatic tumor extension (E +) were independent prognostic factors. A total of 299 patients had complete remission, and 19 relapsed. Patients with declining alpha-fetoprotein (AFP) > 75% after the first two cycles of neoadjuvant chemotherapy had a better EFS and OS than those ≤ 75%. CONCLUSIONS: The survival outcome of HB children has dramatically improved since the implementation of CCCG-HB-2016 therapy. Age ≥ 8 years, R + , and E + were independent risk factors for prognosis. Patients with a declining AFP > 75% after the first two cycles of neoadjuvant chemotherapy had better EFS and OS.

16.
Nurs Open ; 10(11): 7343-7347, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37612835

RESUMO

AIM: To analyse the risk factors for falls in vascular patients and methods to mitigate fall risk in hospitalised patients receiving vascular surgery. DESIGN: This study is a multicentre, retrospective study. METHODS: A total of 112 inpatients that underwent vascular surgery in five hospitals in Shanxi Province from April 2018 to April 2022 were selected. They were divided into two groups according to whether they had fallen or not; 56 patients who fell were taken as the observation group and 56 patients who did not fall were taken as the control group. The risk factors of falls were analysed by univariate and logistic regression. RESULTS: There was no significant difference between the observation and the control groups in male patients and the incidence of falls without family members. In the observation group, the percentage of patients aged ≥65 years old, with a history of falls and/or fractures, long-term medications and a history of osteoporosis was higher than in the control group and showed a statistically significant difference. Multivariate logistic regression analysis showed that advanced age, a history of falls and fractures, long-term medications and a history of osteoporosis were independent risk factors for falls, and the differences were statistically significant. CONCLUSION: Older age, a history of falls and/or fractures, continuous medication for more than 3 months and a history of osteoporosis are the risk factors for falls in hospitalised patients undergoing vascular surgery.


Assuntos
Fraturas Ósseas , Osteoporose , Humanos , Masculino , Idoso , Estudos Retrospectivos , Fraturas Ósseas/epidemiologia , Fatores de Risco , Osteoporose/epidemiologia , Procedimentos Cirúrgicos Vasculares/efeitos adversos
17.
Mater Horiz ; 10(10): 4224-4231, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37538049

RESUMO

Atomically separated frontier molecular orbital (FMO) distribution plays a crucial role in achieving narrowband emissions for multiple resonance (MR)-type thermally activated delayed fluorescence emitters. Directly peripherally decorating a MR framework with donor or acceptor groups is a common strategy for developing MR emitters. However, this approach always induces bonding features and thus spectral broadening as a side effect. How direct donor/acceptor decoration enhances atomic FMO separation while avoiding bonding features has not been explored. For this aim, two MR derivatives are synthesized by integrating two MR frameworks at different sites. Following resonance alignment, DOBNA-m-CzBN avoids breaking nonbonding FMO features at the single connecting bond and shows enhanced MR characteristics, with a sharp emission at 491 nm and a full width at half maximum (FWHM) of 24 nm/118 meV. Conversely, DOBNA-p-CzBN emerges as a bonding feature due to its continuous π-conjugation extension, with a broadened FWHM of 26 nm/132 meV peaking at 497 nm. Impressively, both emitters exhibit outstanding external quantum efficiencies of 37.8-38.6% in organic light-emitting diodes (OLEDs), demonstrating improved performance with rigid acceptor decoration. Distinctly, the electroluminescence of DOBNA-m-CzBN shows a narrower FWHM than that of DOBNA-p-CzBN. This work for the first time reports the enhancement of atomic FMO separation for MR emitters via peripheral decoration through a single bond and provides a more comprehensive illustration for further development of MR emitters.

18.
Angew Chem Int Ed Engl ; 62(35): e202305580, 2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37431732

RESUMO

Hindered by spectral broadening issues with redshifted emission, long-wavelength (e.g., maxima beyond 570 nm) multiple resonance (MR) emitters with full width at half maxima (FWHMs) below 20 nm remain absent. Herein, by strategically embedding diverse boron (B)/nitrogen (N) atomic pairs into a polycyclic aromatic hydrocarbon (PAH) skeleton, we propose a hybrid pattern for the construction of a long-wavelength narrowband MR emitter. The proof-of-concept emitter B4N6-Me realized orange-red emission with an extremely small FWHM of 19 nm (energy unit: 70 meV), representing the narrowest FWHM among all reported long-wavelength MR emitters. Theoretical calculations revealed that the cooperation of the applied para B-π-N and para B-π-B/N-π-N patterns is complementary, which gives rise to both narrowband and redshift characteristics. The corresponding organic light-emitting diode (OLED) employing B4N6-Me achieved state-of-the-art performance, e.g., a narrowband orange-red emission with an FWHM of 27 nm (energy unit: 99 meV), an excellent maximum external quantum efficiency (EQE) of 35.8 %, and ultralow efficiency roll-off (EQE of 28.4 % at 1000 cd m-2 ). This work provides new insights into the further molecular design and synthesis of long-wavelength MR emitters.

19.
Fa Yi Xue Za Zhi ; 39(2): 115-120, 2023 Apr 25.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-37277373

RESUMO

OBJECTIVES: To estimate postmortem interval (PMI) by analyzing the protein changes in skeletal muscle tissues with the protein chip technology combined with multivariate analysis methods. METHODS: Rats were sacrificed for cervical dislocation and placed at 16 ℃. Water-soluble proteins in skeletal muscles were extracted at 10 time points (0 d, 1 d, 2 d, 3 d, 4 d, 5 d, 6 d, 7 d, 8 d and 9 d) after death. Protein expression profile data with relative molecular mass of 14 000-230 000 were obtained. Principal component analysis (PCA) and orthogonal partial least squares (OPLS) were used for data analysis. Fisher discriminant model and back propagation (BP) neural network model were constructed to classify and preliminarily estimate the PMI. In addition, the protein expression profiles data of human skeletal muscles at different time points after death were collected, and the relationship between them and PMI was analyzed by heat map and cluster analysis. RESULTS: The protein peak of rat skeletal muscle changed with PMI. The result of PCA combined with OPLS discriminant analysis showed statistical significance in groups with different time points (P<0.05) except 6 d, 7 d and 8 d after death. By Fisher discriminant analysis, the accuracy of internal cross-validation was 71.4% and the accuracy of external validation was 66.7%. The BP neural network model classification and preliminary estimation results showed the accuracy of internal cross-validation was 98.2%, and the accuracy of external validation was 95.8%. There was a significant difference in protein expression between 4 d and 25 h after death by the cluster analysis of the human skeletal muscle samples. CONCLUSIONS: The protein chip technology can quickly, accurately and repeatedly obtain water-soluble protein expression profiles in rats' and human skeletal muscles with the relative molecular mass of 14 000-230 000 at different time points postmortem. The establishment of multiple PMI estimation models based on multivariate analysis can provide a new idea and method for PMI estimation.


Assuntos
Mudanças Depois da Morte , Análise Serial de Proteínas , Animais , Humanos , Ratos , Análise Multivariada , Tecnologia
20.
Angew Chem Int Ed Engl ; 62(32): e202306413, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37308770

RESUMO

Building blocks and heteroatom alignments are two determining factors in designing multiple resonance (MR)-type thermally activated delayed fluorescence (TADF) emitters. Carbazole-fused MR emitters, represented by CzBN derivatives, and the heteroatom alignments of ν-DABNA are two star series of MR-TADF emitters that show impressive performances from the aspects of building blocks and heteroatom alignments, respectively. Herein, a novel CzBN analog, Π-CzBN, featuring ν-DABNA heteroatom alignment is developed via facile one-shot lithium-free borylation. Π-CzBN exhibits superior photophysical properties with a photoluminescence quantum yield close to 100 % and narrowband sky blue emission with a full width at half maximum (FWHM) of 16 nm/85 meV. It also gives efficient TADF properties with a small singlet-triplet energy offset of 40 meV and a fast reverse intersystem crossing rate of 2.9×105  s-1 . The optimized OLED using Π-CzBN as the emitter achieves an exceptional external quantum efficiency of 39.3 % with a low efficiency roll-off of 20 % at 1000 cd m-2 and a narrowband emission at 495 nm with FWHM of 21 nm/106 meV, making it one of the best reported devices based on MR emitters with comprehensive performance.

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