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1.
Int J Rheum Dis ; 27(6): e15218, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38923187

ABSTRACT

OBJECTIVE: Alterations in gut microbiota have been implicated in the pathogenesis of ankylosing spondylitis (AS), but the underlying mechanisms remain elusive. This study aims to investigate changes in gut microbiota and metabolites in individuals with AS before and after treatment with secukinumab, to identify the biological characteristics specific to AS patients and investigate the potential biomarkers, for optimizing therapeutic strategies more effectively. METHODS: Fecal microbiome data were collected from 30 AS patients before and after secukinumab therapy and compared with data from 40 healthy controls (HC). Additionally, we analyzed the metabolic profile of both groups from plasma. RESULTS: Findings indicated that the treatment-induced changes in the composition of several crucial bacterial groups, including Megamonas, Prevotella_9, Faecalibacterium, Roseburia, Bacteroides, and Agathobacter. Post-treatment, these groups exhibited a distribution more akin to that of the healthy populations compared with their pretreatment status. We identified three gut microbial taxa, namely Prevotellaceae_bacterium_Marseille_P2831, Prevotella_buccae, and Elusimicrobiota, as potential biomarkers for diagnosing individuals at a higher risk of developing AS and assessing disease outcomes. Plasma metabolomics analysis revealed 479 distinct metabolites and highlighted three disrupted metabolic pathways. Integration of microbiome and metabolomics datasets demonstrated a significant degree of correlation, underscoring the impact of the microbiome on metabolic activity. CONCLUSION: Secukinumab can restore the balance of the gut microbiome and metabolites in AS patients, rendering them more similar to those found in the healthy population. The analysis of microbiome and metabolomics data have unveiled some candidate biomarkers capable of evaluating treatment efficacy.


Subject(s)
Antibodies, Monoclonal, Humanized , Feces , Gastrointestinal Microbiome , Metabolomics , RNA, Ribosomal, 16S , Ribotyping , Spondylitis, Ankylosing , Humans , Spondylitis, Ankylosing/drug therapy , Spondylitis, Ankylosing/blood , Spondylitis, Ankylosing/diagnosis , Spondylitis, Ankylosing/microbiology , Gastrointestinal Microbiome/drug effects , Male , Antibodies, Monoclonal, Humanized/therapeutic use , Female , Adult , Feces/microbiology , Treatment Outcome , RNA, Ribosomal, 16S/genetics , Case-Control Studies , Middle Aged , Bacteria/drug effects , Bacteria/genetics , Biomarkers/blood , Predictive Value of Tests , Dysbiosis
2.
BMC Genomics ; 25(1): 564, 2024 Jun 05.
Article in English | MEDLINE | ID: mdl-38840037

ABSTRACT

Mesenchymal Stem Cells are ideal seed cells for tissue repair and cell therapy and have promising applications in regenerative medicine and tissue engineering. Using Platelet-Rich Plasma as an adjuvant to create and improve the microenvironment for Mesenchymal Stem Cells growth can enhance the biological properties of Mesenchymal Stem Cells and improve the efficacy of cell therapy. However, the mechanism by which Platelet-Rich Plasma improves the biological performance of Mesenchymal Stem Cells is still unknown. In this study, by examining the effects of Platelet-Rich Plasma on the biological performance of Mesenchymal Stem Cells, combined with multiomics analysis (Transcriptomics, Proteomics and Metabolomics) and related tests, we analyzed the specific pathways, related mechanisms and metabolic pathways of Platelet-Rich Plasma to improve the biological performance of Mesenchymal Stem Cells. In an in vitro cell culture system, the biological performance of Mesenchymal Stem Cells was significantly improved after replacing Foetal Bovine Serum with Platelet-Rich Plasma, and the genes (ESM1, PDGFB, CLEC7A, CCR1 and ITGA6 et al.) related to cell proliferation, adhesion, growth, migration and signal transduction were significantly upregulated. Platelet-Rich Plasma can enhance the secretion function of MSC exosomes, significantly upregulate many proteins related to tissue repair, immune regulation and anti-infection, and enhance the repair effect of exosomes on skin injury. After replacing Foetal Bovine Serum with Platelet-Rich Plasma, Mesenchymal Stem Cells underwent metabolic reprogramming, the metabolism of amino acids and fatty acids and various signaling pathways were changed, the anabolic pathways of various proteins were enhanced. These results provide a theoretical and technical reference for optimizing the Mesenchymal Stem Cells culture system, improving the biological characteristics and clinical application effects of Mesenchymal Stem Cells.


Subject(s)
Cell Proliferation , Mesenchymal Stem Cells , Platelet-Rich Plasma , Proteomics , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/cytology , Platelet-Rich Plasma/metabolism , Humans , Metabolomics , Animals , Cells, Cultured , Gene Expression Profiling , Exosomes/metabolism , Multiomics
3.
Eur J Pharmacol ; 976: 176665, 2024 Aug 05.
Article in English | MEDLINE | ID: mdl-38797312

ABSTRACT

OBJECTIVE: Sepsis is frequently complicated by neuroinflammation. Gibberellic acid (GA3) is recognized for its anti-inflammatory properties. In this study, our objective was to investigate whether GA3 could alleviate Nuclear factor-kappa B (NF-κB) -dependent inflammatory stress in sepsis-induced neuroinflammation. METHODS: C57BL/6 J mice were administered 10 mg/kg lipopolysaccharide (LPS) to induce sepsis. BV2 cells were pre-incubated with GA3 and subjected lipopolysaccharide stimulation to replicate the inflammatory microglia during sepsis. Subsequently, we assessed the release of IL-6, TNF-α, and IL-1ß, along with the expression of Zbtb16, NF-κB, and IκB. To investigate whether any observed anti-inflammatory effects of GA3 were mediated through a Zbtb16-dependent mechanism, Zbtb16 was silenced using siRNA. RESULTS: GA3 improved the survival of sepsis mice and alleviated post-sepsis cognitive impairment. Additionally, GA3 attenuated microglial M1 activation (pro-inflammatory phenotype), inflammation, and neuronal damage in the brain. Moreover, GA3 inhibited the release of TNF-α, IL-6, and IL-1ß in microglia stimulated with LPS. The NF-κB signaling pathway emerged as one of the key molecular pathways associated with the impact of GA3 on LPS-stimulated microglia. Lastly, GA3 upregulated Zbtb16 expression in microglia that had been downregulated by LPS. The inhibitory effects of GA3 on microglial M1 activation were partially reversed through siRNA knockdown of Zbtb16. CONCLUSIONS: Pre-incubation of microglia with GA3 led to the upregulation of the NF-κB regulator, Zbtb16. This process counteracted LPS-induced microglial M1 activation, resulting in an anti-inflammatory effect upon subsequent LPS stimulation.


Subject(s)
Gibberellins , Lipopolysaccharides , Mice, Inbred C57BL , Microglia , NF-kappa B , Sepsis , Animals , Sepsis/complications , Sepsis/drug therapy , Sepsis/metabolism , Mice , NF-kappa B/metabolism , Male , Microglia/drug effects , Microglia/metabolism , Gibberellins/pharmacology , Neuroinflammatory Diseases/drug therapy , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/therapeutic use , Signal Transduction/drug effects , Cell Line , Cytokines/metabolism , Inflammation/drug therapy , Inflammation/metabolism
4.
Clin Rheumatol ; 43(7): 2237-2244, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38761246

ABSTRACT

OBJECTIVE: This study aimed to classify idiopathic inflammatory myopathy (IIM) patients with cardiac involvement (IIM-CI) into different categories based on their clinical phenotypes via cluster analysis and to explore their differences in outcomes. METHODS: IIM-CI patients admitted to Peking Union Medical College Hospital from January 2015 to June 2021 were retrieved. The clinical data, laboratory examinations, and treatment were retrospectively reviewed, and the outcome was traced. A second-order clustering method was employed for categorization. RESULTS: A total of 88 IIM-CI patients were enrolled in this study and were classified into two categories through cluster analysis. Category I consisted of patients who exhibited distinct cardiac structural and functional changes, such as enlargement of atriums and/or ventricles, along with the remarkable heart insufficiency biomarkers, whereas patients of category II displayed more widely systemic injuries and intensive skeletal muscle weakness. In comparison, pulmonary hypertension (58.8% vs 16.7%, p < 0.01), arrhythmia (82.4% vs 27.8%, p < 0.01), and positive serum anti-mitochondrial-M2 antibody (52.9% vs 5.6%, p < 0.01) were more prevalent in category I than in category II, and serum N-terminal pro-B-type natriuretic peptide levels (1703.5 pg/L vs 364.0 pg/L, p = 0.02) were significantly elevated in category I, whereas skeletal muscle weakness (50.0% vs 74.1%, p = 0.02), interstitial lung disease (20.6% vs 63.0%, p < 0.01), skin rash (11.8% vs 48.1%, p < 0.01), arthralgia (2.9% vs 27.8%, p < 0.01), fever (2.9% vs 27.8%, p < 0.01), and dysphagia (2.9% vs 22.2%, p < 0.01) were more common in category II patients. Heart failure was the primary cause of death in category I, but severe pneumonia was predominantly responsible for deaths in category II. CONCLUSION: Two categories of IIM-CI were identified based on clinical features with distinctive characteristics. Two categories exhibited differences in clinical manifestations, autoantibody profiles, and the primary cause of death.


Subject(s)
Myositis , Phenotype , Humans , Female , Male , Myositis/complications , Myositis/blood , Middle Aged , Retrospective Studies , Cluster Analysis , Adult , Aged , Autoantibodies/blood , Natriuretic Peptide, Brain/blood , Hypertension, Pulmonary , Heart Diseases/complications , Peptide Fragments
5.
Micromachines (Basel) ; 15(5)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38793187

ABSTRACT

Thin-walled bearings are widely used owing to the advantages of their light structure, high hardness, and strong load-carrying capacity. However, thin-walled bearings are often prone to deformation during the machining process, which can seriously affect the performance of the bearings. In addition, the machining deformation and quality of bearings are difficult to balance. To address the above issues, this paper investigates the effects of the machining parameters on the machining deformation, surface quality, and machining efficiency of a thin-walled bearing during the roughing stage. The dynamic balance between deformation inhibition and high quality in rough grinding was studied, and the optimal parameters for thin-walled bearing outer ring grinding were obtained. The deformation mechanism of thin-walled bearings caused by grinding was revealed through simulation and experimental analysis. The results show that the machining deformation and quality reach a balance when the workpiece speed is 55 r/min, the grinding wheel rotational speed is 2000 r/min, and the feed rate is 0.1 mm/min. Deformation increases with the increase in workpiece speed and grinding wheel speed. At the same time, the surface roughness increases with the increase in the workpiece speed, but the increase in the wheel speed will improve the surface roughness. As the workpiece speed increases, the surface topography shows a more pronounced stockpile of material, which is ameliorated by an increase in grinding wheel speed. As the rotational speed of the workpiece increases, the number of abrasive grains involved in the process per unit of time decreases, and the surface removal of the workpiece is less effective, while the increase in the rotational speed of the grinding wheel has the opposite effect. The grinding deformation of thin-walled bearings is mainly induced by machining heat and stress. As the rotational speed increases, the heat flux in the grinding zone increases. More heat flux flows into the surface of the workpiece, causing an increase in thermal stresses on the inner surface of the bearing collar, leading to greater deformation. The temperature in the grinding area can be reduced during machining, realizing a reduction in deformation. The research content contributes to the balance between high quality and low distortion in machining processes.

6.
J Med Chem ; 67(11): 9431-9446, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38818879

ABSTRACT

Synthetic lethality has recently emerged as a new approach for the treatment of mutated genes that were previously considered undruggable. Targeting methionine adenosyltransferase 2A (MAT2A) in cancers with deletion of the methylthioadenosine phosphorylase (MTAP) gene leads to synthetic lethality and thus has attracted significant interest in the field of precise anticancer drug development. Herein, we report the discovery of a series of novel MAT2A inhibitors featuring a pyrazolo[3,4-c]quinolin-4-one skeleton based on structure-based drug design. Further optimization led to compound 39, which has a high potency for inhibiting MAT2A and a remarkable selectivity for MTAP-deleted cancer cell lines. Compound 39 has a favorable pharmacokinetic profile with high plasma exposure and oral bioavailability, and it exhibits significant efficacy in xenograft MTAP-depleted models. Moreover, 39 demonstrates excellent brain exposure with a Kpuu of 0.64 in rats.


Subject(s)
Brain , Drug Design , Enzyme Inhibitors , Methionine Adenosyltransferase , Methionine Adenosyltransferase/antagonists & inhibitors , Methionine Adenosyltransferase/metabolism , Humans , Animals , Structure-Activity Relationship , Rats , Brain/metabolism , Enzyme Inhibitors/pharmacology , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacokinetics , Enzyme Inhibitors/chemical synthesis , Cell Line, Tumor , Antineoplastic Agents/pharmacology , Antineoplastic Agents/pharmacokinetics , Antineoplastic Agents/chemistry , Antineoplastic Agents/chemical synthesis , Mice , Male , Rats, Sprague-Dawley , Xenograft Model Antitumor Assays
7.
Clin Rheumatol ; 43(5): 1541-1550, 2024 May.
Article in English | MEDLINE | ID: mdl-38565803

ABSTRACT

OBJECTIVE: Systemic lupus erythematosus (SLE) is associated with a significant risk of atherosclerotic cardiovascular disease, especially in the development of premature atherosclerosis. Specific prediction models for premature atherosclerosis in SLE patients are still limited. The objective of this study was to establish a predictive model for premature atherosclerosis in SLE. METHOD: The study collected clinical and laboratory data from 148 SLE patients under the age of 55, between January 2021 and June 2023. The least absolute shrinkage and selection operator logistic regression model was utilized to identify potentially relevant features. Subsequently, a nomogram was developed using multivariable logistic analysis. The performance of the nomogram was evaluated through a receiver-operating characteristic curve, calibration curve, and decision curve analysis (DCA). RESULTS: A total of 148 SLE patients who fulfilled the inclusion criteria were enrolled in the study, of whom 53 patients (35.81%) met the definition of premature atherosclerosis. Hypertension, antiphospholipid syndrome, azathioprine use, duration of glucocorticoid, and age of patients were included in the multivariable regression. The nomogram, based on the non-overfitting multivariable model, was internally validated and demonstrated sufficient clinical utility for assessing the risk of premature atherosclerosis (area under curve: 0.867). CONCLUSIONS: The comprehensive nomogram constructed in this study serves as a useful and convenient tool for evaluating the risk of premature atherosclerosis in SLE patients. It is helpful for clinicians to early identify SLE patients with premature atherosclerosis and facilitates the implementation of more effective preventive measures. Key Points • SLE patients are at a significantly higher risk of developing premature atherosclerosis compared to the general population, and this risk persists even in cases with low disease activity. Traditional models used to evaluate and predict premature atherosclerosis in SLE patients often underestimate the risk. • This study establishes a comprehensive and visually orientated predictive model of premature atherosclerosis in SLE patients, based on clinical characteristics. • The scoring system allows for convenient and effective prediction of individual incidence of premature atherosclerosis, and could provide valuable information for identification and making further intervention decision.


Subject(s)
Antiphospholipid Syndrome , Atherosclerosis , Hypertension , Lupus Erythematosus, Systemic , Humans , Lupus Erythematosus, Systemic/complications , Lupus Erythematosus, Systemic/epidemiology , Atherosclerosis/etiology , Antiphospholipid Syndrome/complications , Hypertension/complications , Incidence , Risk Factors
8.
Sci Rep ; 14(1): 6170, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38486035

ABSTRACT

Employee scheduling aims to assign employees to shifts to satisfy daily workload and constraints. Some employee scheduling problems and their variants have been proven NP-hard, and a series of works have been done. However, the existing algorithms consider the fixed work time, which may cause plenty of overstaffing and understaffing phenomenons. Hence, this paper proposes a fast-flexible strategy based approach (FFS) to solve it. FFS introduces the idea of soft work time, which allows the work time of employees can be adjusted in a range. Based on this, we set the flextime strategy to decide the specific work time of each employee every day. Besides, FFS adopts a pairwise-allocated strategy and proficiency average matrix to boost its efficiency and effectiveness. Finally, the extensive experimental evaluation shows that FFS is more effective and efficient than the baselines for solving the employee scheduling problem considering soft work time.

9.
J Am Chem Soc ; 146(12): 8298-8307, 2024 Mar 27.
Article in English | MEDLINE | ID: mdl-38498306

ABSTRACT

Antiferroelectric materials with an electrocaloric effect (ECE) have been developed as promising candidates for solid-state refrigeration. Despite the great advances in positive ECE, reports on negative ECE remain quite scarce because of its elusive physical mechanism. Here, a giant negative ECE (maximum ΔS ∼ -33.3 J kg-1 K-1 with ΔT ∼ -11.7 K) is demonstrated near room temperature in organometallic perovskite, iBA2EA2Pb3I10 (1, where iBA = isobutylammonium and EA = ethylammonium), which is comparable to the greatest ECE effects reported so far. Moreover, the ECE efficiency ΔS/ΔE (∼1.85 J cm kg-1 K-1 kV-1) and ΔT/ΔE (∼0.65 K cm kV-1) are almost 2 orders of magnitude higher than those of classical inorganic ceramic ferroelectrics and organic polymers, such as BaTiO3, SrBi2Ta2O9, Hf1/2Zr1/2O2, and P(VDF-TrFE). As far as we know, this is the first report on negative ECE in organometallic hybrid perovskite ferroelectric. Our experimental measurement combined with the first-principles calculations reveals that electric field-induced antipolar to polar structural transformation results in a large change in dipolar ordering (from 6.5 to 45 µC/cm2 under the ΔE of 18 kV/cm) that is closely related to the entropy change, which plays a key role in generating such giant negative ECE. This discovery of field-induced negative ECE is unprecedented in organometallic perovskite, which sheds light on the exploration of next-generation refrigeration devices with high cooling efficiency.

11.
Angew Chem Int Ed Engl ; 63(14): e202401221, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38342759

ABSTRACT

Metal-free molecular antiferroelectric (AFE) holds a promise for energy storage on account of its unique physical attributes. However, it is challenging to explore high-curie temperature (Tc) molecular AFEs, due to the lack of design strategies regarding the rise of phase transition energy barriers. By renewing the halogen substitution strategy, we have obtained a series of high-Tc molecular AFEs of the halogen-substituted phenethylammonium bromides (x-PEAB, x=H/F/Cl/Br), resembling the binary stator-rotator system. Strikingly, the p-site halogen substitution of PEA+ cationic rotators raises their phase transition energy barrier and greatly enhances Tc up to ~473 K for Br-PEAB, on par with the record-high Tc values for molecular AFEs. As a typical case, the member 4-fluorophenethylammonium bromide (F-PEAB) shows notable AFE properties, including high Tc (~374 K) and large electric polarization (~3.2 µC/cm2). Further, F-PEAB also exhibits a high energy storage efficiency (η) of 83.6 % even around Tc, catching up with other AFE oxides. This renewing halogen substitution strategy in the molecular AFE system provides an effective way to design high-Tc AFEs for energy storage devices.

12.
Food Chem ; 445: 138720, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38359570

ABSTRACT

The tendency of ovotransferrin (OVT) to unfold and aggregate under 60 °C severely restricted sterilization temperature during egg processing. Searching for efficient strategies to improve OVT thermal stability is essential for improving egg product quality and processing suitability. Here, we investigated the effect of sulfate polysaccharide (dextran sulfate, DS) on heat-induced aggregation of OVT. We found that DS can effectively suppress amorphous aggregation of OVT at pH 7.0 after heating. Strikingly, the addition of 5 µM DS fully suppressed insoluble aggregates formation of 0.5 mg/mL OVT. Structure analysis confirmed that DS preserves nearly the entire secondary and tertiary structure of OVT during heating. The steric hindrance effect arising from strong electrostatic interactions between OVT and DS, coupled with reduced OVT hydrophobicity, is the underlying mechanism in suppressing protein-protein interactions, thus enhancing thermal stability. These findings suggest DS could act as protein stabilizers and chaperones, enhancing the thermostability of heat-sensitive proteins.


Subject(s)
Conalbumin , Hot Temperature , Conalbumin/chemistry , Dextran Sulfate , Temperature , Static Electricity
13.
Adv Mater ; 36(23): e2312237, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38363019

ABSTRACT

Inverted inorganic perovskite solar cells (PSCs) is potential as the top cells in tandem configurations, owing to the ideal bandgap, good thermal and light stability of inorganic perovskites. However, challenges such as mismatch of energy levels between charge transport layer and perovskite, significant non-radiative recombination caused by surface defects, and poor water stability have led to the urgent need for further improvement in the performance of inverted inorganic PSCs. Herein, the fabrication of efficient and stable CsPbI3-xBrx PSCs through surface treatment of (3-mercaptopropyl) trimethoxysilane (MPTS), is reported. The silane groups in MPTS can in situ crosslink in the presence of moisture to build a 3-dimensional (3D) network by Si-O-Si bonds, which forms a hydrophobic layer on perovskite surface to inhibit water invasion. Additionally, -SH can strongly interact with the undercoordinated Pb2+ at the perovskite surface, effectively minimizing interfacial charge recombination. Consequently, the efficiency of the inverted inorganic PSCs improves dramatically from 19.0% to 21.0% under 100 mW cm-2 illumination with MPTS treatment. Remarkably, perovskite films with crosslinked MPTS exhibit superior stability when soaking in water. The optimized PSC maintains 91% of its initial efficiency after aging 1000 h in ambient atmosphere, and 86% in 800 h of operational stability testing.

14.
Int J Rheum Dis ; 27(1): e14899, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37705400

ABSTRACT

Seronegative rheumatoid arthritis (SNRA) can be a rapid-progressing and highly disabling disease. Anti-PTX3 autoantibody may be a potential biomarker in SNRA diagnosis. SNRA patients could respond well to upadacitinib.


Subject(s)
Antirheumatic Agents , Arthritis, Rheumatoid , Humans , Arthritis, Rheumatoid/diagnosis , Arthritis, Rheumatoid/drug therapy , Heterocyclic Compounds, 3-Ring/therapeutic use , Biomarkers , Antirheumatic Agents/therapeutic use
15.
Comput Biol Chem ; 108: 107992, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38056378

ABSTRACT

Most existing graph neural network-based methods for predicting miRNA-disease associations rely on initial association matrices to pass messages, but the sparsity of these matrices greatly limits performance. To address this issue and predict potential associations between miRNAs and diseases, we propose a method called strengthened hypergraph convolutional autoencoder (SHGAE). SHGAE leverages multiple layers of strengthened hypergraph neural networks (SHGNN) to obtain robust node embeddings. Within SHGNN, we design a strengthened hypergraph convolutional network module (SHGCN) that enhances original graph associations and reduces matrix sparsity. Additionally, SHGCN expands node receptive fields by utilizing hyperedge features as intermediaries to obtain high-order neighbor embeddings. To improve performance, we also incorporate attention-based fusion of self-embeddings and SHGCN embeddings. SHGAE predicts potential miRNA-disease associations using a multilayer perceptron as the decoder. Across multiple metrics, SHGAE outperforms other state-of-the-art methods in five-fold cross-validation. Furthermore, we evaluate SHGAE on colon and lung neoplasms cases to demonstrate its ability to predict potential associations. Notably, SHGAE also performs well in the analysis of gastric neoplasms without miRNA associations.


Subject(s)
MicroRNAs , MicroRNAs/genetics , Algorithms , Neural Networks, Computer , Computational Biology/methods
17.
Small ; 20(24): e2310529, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38148294

ABSTRACT

2D organic-inorganic hybrid perovskites (OIHPs) have become one of the hottest research topics due to their excellent environmental stability and unique optoelectronic properties. Recently, the ferroelectricity and thermochromism of 2D OIHPs have attracted increasing interests. Integrating ferroelectricity and thermochromism into perovskites can significantly promote the development of multichannel intelligent devices. Here, a novel 2D Dion-Jacobson OIHP of the formula (3AMP)PbI4 (where 3AMP is 3-(aminomethyl)pyridinium) is reported, which has a remarkable spontaneous polarization value (Ps) of 15.6 µC cm-2 and interesting thermochromism. As far it is known, such a large Ps value is the highest for 2D OIHPs recorded so far. These findings will inspire further exploration and application of multifunctional perovskites.

18.
Angew Chem Int Ed Engl ; 63(7): e202318742, 2024 Feb 12.
Article in English | MEDLINE | ID: mdl-38153344

ABSTRACT

Recently, boron (B)/nitrogen (N)-embedded polycyclic aromatic hydrocarbons (PAHs), characterized by multiple resonances (MR), have attracted significant attention owing to their remarkable features of efficient narrowband emissions with small full width at half maxima (FWHMs). However, developing ultra-narrowband pure-green emitters that comply with the Broadcast Service Television 2020 (BT2020) standard remains challenging. Precise regulation of the MR distribution regions allows simultaneously achieving the emission maximum, FWHM value, and spectral shape that satisfy the BT2020 standard. The proof-of-concept molecule TPABO-DICz exhibited ultrapure green emission with a dominant peak at 515 nm, an extremely small FWHM of 17 nm, and Commission Internationale de l'Eclairage (CIE) coordinates of (0.17, 0.76). The corresponding bottom-emitting organic light-emitting diode (OLED) exhibited a remarkably high CIEy value (0.74) and maximum external quantum efficiency (25.8 %). Notably, the top-emitting OLED achieved nearly BT2020 green color (CIE: 0.14, 0.79) and exhibited a state-of-the-art maximum current efficiency of 226.4 cd A-1 , thus fully confirming the effectiveness of the above strategy.

19.
Nat Commun ; 14(1): 5821, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37726264

ABSTRACT

Broadband spectral photoresponse has shown bright prospects for various optoelectronic devices, while fulfilling high photoactivity beyond the material bandgap is a great challenge. Here, we present a molecular pyroelectric, N-isopropylbenzylaminium trifluoroacetate (N-IBATFA), of which the broadband photo-pyroelectric effects allow for self-driven wide spectral photodetection. As a simple organic binary salt, N-IBATFA possesses a large polarization (~9.5 µC cm-2), high pyroelectric coefficient (~6.9 µC cm-2 K-1) and figures-of-merits (FV = 187.9 × 10-2 cm2 µC-1; FD = 881.5 × 10-5 Pa-0.5) comparable to the state-of-art pyroelectric materials. Particularly, such intriguing attributes endow broadband photo-pyroelectric effect, namely, transient currents covering ultraviolet (UV, 266 nm) to near-infrared (NIR, 1950 nm) spectral regime, which breaks the restriction of its optical absorption and thus allows wide UV-NIR spectral photodetection. Our finding highlights the potential of molecular system as high-performance candidates toward self-powered wide spectral photodetection.

20.
Angew Chem Int Ed Engl ; 62(45): e202309416, 2023 Nov 06.
Article in English | MEDLINE | ID: mdl-37733923

ABSTRACT

Ferroelectric photovoltaics driven by spontaneous polarization (Ps ) holds a promise for creating the next-generation optoelectronics, spintronics and non-volatile memories. However, photoactive ferroelectrics are quite scarce in single homogeneous phase, owing to the severe Ps fatigue caused by leakage current of photoexcited carriers. Here, through combining inorganic and organic components as building blocks, we constructed a series of ferroelectric semiconductors of 2D hybrid perovskites, (HA)2 (MA)n-1 Pbn Br3n+1 (n=1-5; HA=hexylamine and MA=methylamine). It is intriguing that their Curie temperatures are greatly enhanced by reducing the thickness of inorganic frameworks from MAPbBr3 (n=∞, Tc =239 K) to n=2 (Tc =310 K, ΔT=71 K). Especially, on account of the coupling of room-temperature ferroelectricity (Ps ≈1.5 µC/cm2 ) and photoconductivity, n=3 crystal wafer was integrated as channel field effect transistor that shows excellent a large short-circuit photocurrent ≈19.74 µA/cm2 . Such giant photocurrents can be modulated through manipulating gate voltage in a wide range (±60 V), exhibiting gate-tunable memory behaviors of three current states ("-1/0/1" states). We believe that this work sheds light on further exploration of ferroelectric materials toward new non-volatile memory devices.

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