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1.
Chemistry ; 28(68): e202202305, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36048574

RESUMO

The harnessing of heavy atom effect of chalcogen elements offers a way for boosting the thermally activated delayed fluorescence (TADF) of purely organic luminescent materials that can harvest triplet excitons. However, the conformational and electronic variations induced by the heavy and large atoms may also have adverse effects on the TADF properties. Herein, the design, synthesis, and structures of a new type of through-space charge transfer (TSCT) emitters containing benzothiazino[2,3,4-kl]phenothiazine (DPTZ) as the donor unit are reported. The influences of S atoms on the emission properties have been systematically investigated by means of theoretical simulations, electrochemical and spectroscopic studies. Although the presence of π-stacking interactions and calculated spin-orbit coupling (SOC) values are beneficial for TSCT-TADF properties, the triplet TSCT states are uplifted to above the locally excited (LE) state of the acceptor moieties. As a result, the new emitters display longer delayed fluorescence lifetimes (τDF ) of 255.0-114.3 µs and lower PLQYs of 45-61 % in comparison with the O-containing congeners (τDF =26.9-6.8 µs; PLQYs=74-71 %). This work highlights that a full consideration of various effects is essential when making use of heavy chalcogen atoms for the design of TADF emitters.

2.
Int J Clin Pract ; 2022: 5684293, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35936067

RESUMO

Background: Influence of iguratimod on bone mineral density (BMD) and biomarkers of bone metabolism in patients with rheumatoid arthritis (RA) remains not determined. Accordingly, a meta-analysis was performed for systematical evaluation. Methods: Relevant randomized controlled trials (RCTs) were retrieved by searching of PubMed, Embase, Cochrane's Library, China National Knowledge Infrastructure (CNKI), and Wanfang databases. A random-effect model was used to pool the results. Results: In total, 24 RCTs including 2439 patients with RA contributed to the meta-analysis. Pooled results showed that compared to methotrexate alone, additional use of iguratimod 25 mg Bid for 12∼24 weeks significantly improved lumbar-spine BMD (mean difference [MD]: 0.12, 95% confidence interval [CI]: 0.04 to 0.20, p=0.002, I 2 = 39%) in patients with RA. Moreover, treatment with iguratimod was associated with increased serum osteoprotegerin (MD: 180.36 pg/ml, 95% CI: 122.52 to 238.20, p < 0.001, I 2 = 48%), and decreased serum receptor activator for nuclear factor kappa-B ligand (MD: -10.65 pmol/l, 95% CI: -15.59 to -5.72, p < 0.001, I 2 = 53%). In addition, iguratimod was associated with increased bone formation markers such as the serum N-terminal middle molecular fragment of osteocalcin (MD: 4.23 ng/ml, 95% CI: 3.74 to 4.71, p < 0.001, I 2 = 35%) and total procollagen type I amino-terminal propeptide (MD: 9.10 ng/ml, 95% CI: 7.39 to 10.80, p < 0.001, I 2 = 86%), but decreased the bone resorption marker such as serum ß-C terminal cross-linking telopeptide of type 1 collagen (MD: -0.18 pg/ml, 95% CI: -0.21 to -0.14, p < 0.001, I 2 = 70%). Conclusions: Iguratimod could prevent the bone loss and improve the bone metabolism in patients with RA.


Assuntos
Artrite Reumatoide , Biomarcadores , Cromonas , Humanos , Metotrexato/uso terapêutico , Sulfonamidas
13.
Arch Med Sci ; 20(2): 375-383, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38757018

RESUMO

Introduction: The aim of the study was to evaluate the risk factors for cervical instability in rheumatoid arthritis (RA). Material and methods: Computer searches were conducted in PubMed, Embase, Cochrane Library, the China National Knowledge Infrastructure (CNKI) database, the Wan Fang database, the Chinese Scientific Journal Databases (VIP) database, and the Chinese Biomedical Literature database (CBM) from their establishment until November 2022. Results: A total of 8 articles were included in this study, including 1 cross-sectional study, 5 case-control studies, and 2 cohort study, including 3078 patients with RA. Meta-analysis results showed that: male sex (OR = 1.70, 95% CI: 1.19-2.42), course of disease (OR = 1.72, 95% CI: 1.29-2.28), long-term glucocorticosteroid use (OR = 2.84, 95% CI: 1.97-2.40), Steinbrocker staging (OR = 2.30, 95% CI: 1.61-3.28), disability at baseline (OR = 24.57, 95% CI: 5.51-109.60), peripheral joint destruction (OR = 2.24, 95% CI: 1.56-3.21), Steinbrocker stage I-IV progression to disability (OR = 20.08, 95% CI: 4.18-96.53), and previous joint surgery (OR = 1.54, 95% CI: 1.06-2.26) are the main risk factors for cervical instability in RA. Conclusions: There are many risk factors for cervical instability in RA. In clinical practice, special attention should be paid to patients who are male, have a longer course of disease, have long-term glucocorticosteroid use, have previous joint surgery, have peripheral joint damage, and develop disability in Steinbrocker stage I-IV. Attention should be paid to the high-risk groups mentioned above, and effective measures such as early screening and full monitoring should be taken to prevent the occurrence of cervical instability in RA.

14.
ACS Omega ; 8(36): 32884-32891, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37720804

RESUMO

The analysis of performance degradation in lithium-ion batteries plays a crucial role in achieving accurate and efficient fault diagnosis as well as safety management. This paper proposes a method for studying the degradation pattern of lithium-ion batteries and establishing the structure-activity relationship between internal and external parameters by employing a lumped particle diffusion model. To simulate real-world operating conditions, a cycle life test was conducted with the constant current-constant voltage (CC-CV) charge mode and the discharge mode under New European Driving Cycle (NEDC) working condition. The test aimed to analyze the variations in the external macroscopic characteristic parameters of the battery. Building upon this analysis, a lumped particle diffusion model was constructed, and the model parameters were identified using the Levenberg-Marquardt (L-M) algorithm. Subsequently, the ohmic, activation, and concentration losses of the battery under different aging conditions were determined, revealing the internal state evolution during the degradation process of lithium-ion batteries. The findings indicate that the lumped particle diffusion model provides a comprehensive explanation of the internal mechanisms contributing to the performance degradation of lithium-ion batteries. Moreover, the proposed method offers a novel perspective for the real-time quantitative analysis of lithium-ion battery performance degradation.

15.
Food Chem ; 405(Pt B): 134963, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36413846

RESUMO

Various types of fluorescent nanoparticles have been proposed for the detection of veterinary drug residues in food. However, structure-induced fluorescence nanoparticles with biodegradability and the capacity to conjugate with molecular recognition elements are lacking. Here, a biodegradable tryptophan-phenylalanine dipeptide-based nanomaterial was assembled and modified with a sulfadimethoxine aptamer (TPNPs@aptamer). Then, a novel and efficient fluorescence sensing strategy, based on TPNPs@aptamer and BHQ1-labeled single-stranded DNA (BHQ1@cDNA), was developed for sulfadimethoxine determination. Under optimal conditions, the fluorescence was linear in the range of 0-200 ng/mL sulfadimethoxine with a detection limit of 1.47 ng/mL (S/N = 3). Satisfactory recoveries of standard additions were found between 92.88 % and 114.15 % for water and milk samples with a relative standard deviation less than 5.0 %, suggesting that the proposed fluorescence sensing strategy can be applied reliably in sulfadimethoxine analysis of liquid foods.


Assuntos
Dipeptídeos , Nanopartículas , Fluorescência , Sulfadimetoxina , Oligonucleotídeos
16.
Food Chem ; 406: 135081, 2023 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-36463602

RESUMO

Olaquindox residues in food from its illegal use has received great attention. Here, an immunoassay strategy integrating an upconversion nanoparticle (UCNP)-based immunochromatographic strip with a fluorescence reader was proposed for the highly selective and sensitive detection of olaquindox. Polyacrylic acid-functionalized UCNPs were synthesized using a simple ligand exchange process and combined with an olaquindox polyclonal antibody to form a fluorescent probe. This approach achieved a sensitive response and specific recognition of olaquindox. A convenient upconversion fluorescence reader was introduced to implement accurate and sensitive quantitative analysis of olaquindox based on the fluorescence intensity of control and test lines on a strip. Under optimal conditions, the method demonstrated a favorable linear range (0-50 ng/mL) and sensitive detection (1.42 ng/mL, S/N = 3). This method was applied successfully to determine olaquindox in fish muscle and water samples, and results were consistent with an HPLC approach, and considered a promising strategy for monitoring olaquindox residuals.


Assuntos
Nanopartículas , Animais , Nanopartículas/química , Imunoensaio/métodos , Músculos , Água , Limite de Detecção
17.
Comput Intell Neurosci ; 2022: 8966063, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248948

RESUMO

Objective: To compare the efficacy of uterine artery embolization (UAE) with traditional methods for treating endometriosis. Methods: The randomized controlled trials of uterine artery embolization and other medical treatments for endometriosis in PubMed, Embase, Web of Science, Cochrane Library, China Journal Full-Text Database, Wanfang Database, VIP Database, and China Biomedical Literature Database were retrieved by computer. The search time was up to June 2022. The quality of articles was evaluated by Cochrane ROB 2.0, and meta-analysis was performed by Stata15.1 software. Results: 7 studies were finally included. Meta-analysis showed that the serum CA125 level after uterine artery embolization was significantly lower than that in the control group (SMD = -0.85, 95%CI (-1.12, -0.59)], and the postoperative visual analogue scale (VAS) of dysmenorrhea was significantly lower than that in the control group (SMD = -1.86, 95%CI (-2.21, -1.50)) There was no significant difference in the effective rate, FSH level, E2 level, and LH level between the two groups. Conclusion: UAE can effectively reduce the VAS score of dysmenorrhea and serum CA125 level for treating endometriosis. However, due to the limitation of the quality of included articles, more large sample size and high quality RCTs are needed to provide stronger evidence-based medicine evidence for clinical practice.


Assuntos
Endometriose , Embolização da Artéria Uterina , China , Dismenorreia/tratamento farmacológico , Endometriose/tratamento farmacológico , Feminino , Hormônio Foliculoestimulante/uso terapêutico , Humanos , Embolização da Artéria Uterina/efeitos adversos , Embolização da Artéria Uterina/métodos
18.
Materials (Basel) ; 15(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35407866

RESUMO

The microstructure and precipitate evolution of as-cast Mg-Nd alloys with different contents of Nd was investigated via experimental and simulation methods. The research showed that the as-cast microstructure of Mg-Nd alloy consisted of α-Mg dendrites and the intermetallic phases. A metastable ß phase precipitated, followed by α-Mg dendrites that could be confirmed as Mg12Nd by X-ray diffraction (XRD) analysis. The amount of ß-Mg12Nd presented a rising trend with increasing Nd additions. In addition, the tertiary phase was also observed in as-cast Mg-Nd alloy when Nd content was greater than 3 wt.%, which precipitated from the oversaturated α-Mg matrix. The tertiary phase should be ß1-Mg3Nd, which is also a metastable phase with a face-centered cubic lattice. However, it is a pity that the tertiary phase was not detected by the XRD technique. Moreover, an effective cellular automaton (CA) model was explored and applied to simulate the time-dependent α-Mg/ß1-Mg3Nd eutectic growth. The simulated results of α-Mg/ß1-Mg3Nd eutectic growth in Mg-3Nd presented that the growth of α-Mg dendrites was accompanied by the nucleation and growth of ß1-Mg3Nd precipitates and eventually formed a eutectic structure. The eutectic morphologies for Mg-Nd system alloys with different Nd contents were also simulated using the proposed model, and the results revealed that α-Mg dendrite was a refinement, and the amount of α-Mg/ß1-Mg3Nd eutectic was promoted, with increasing Nd content.

19.
Research (Wash D C) ; 2022: 9892802, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935129

RESUMO

Organic push-pull systems featuring through-space charge transfer (TSCT) excited states have been disclosed to be capable of exhibiting thermally activated delayed fluorescence (TADF), but to realize high-efficiency long-wavelength emission still remains a challenge. Herein, we report a series of strongly emissive orange-red and red TSCT-TADF emitters having (quasi)planar and rigid donor and acceptor segments which are placed in close proximity and orientated in a cofacial manner. Emission maxima (λ em) of 594-599 nm with photoluminescence quantum yields (PLQYs) of up to 91% and delayed fluorescence lifetimes of down to 4.9 µs have been achieved for new acceptor-donor-acceptor (A-D-A) molecules in doped thin films. The presence of multiple acceptors and the strong intramolecular π-stacking interactions have been unveiled to be crucial for the efficient low-energy TSCT-TADF emissions. Organic light-emitting diodes (OLEDs) based on the new A-D-A emitters demonstrated electroluminescence with maximum external quantum efficiencies (EQEs) of up to 23.2% for the red TSCT-TADF emitters. An EQE of 18.9% at the brightness of 1000 cd m-2 represents one of the highest values for red TADF OLEDs. This work demonstrates a modular approach for developing high-performance red TADF emitters through engineering through-space interactions, and it may also provide implications to the design of TADF emitter with other colours.

20.
ACS Omega ; 7(21): 17797-17810, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35664594

RESUMO

This paper proposes a revised variation disturbance method to provide valuable information and reference for fuel design or optimization of internal combustion engines to realize the comprehensive and quantitative evaluation of the effects of blending agents on the combustion performance of primary fuels. In this method, methanol and ethanol are blended into gasoline to form six kinds of alcohol-gasoline (E10, E20, E30, M10, M20, and M30). Then, the ignition delay, adiabatic flame temperature, component concentration, fuel-burning rate, extinction strain rate, and CO emission of gasoline and alcohol-gasoline are studied by system simulation in a wide range of operating conditions. Based on the new variation disturbance method, the effects of methanol and ethanol on the combustion performance of gasoline are next analyzed globally and characterized quantitatively. The comprehensive results of ethanol and methanol on the gasoline's combustion are visually presented. The method proposed in this paper is preliminarily validated based on the analysis of the microscopic mechanism of combustion. The results show that the blending of ethanol and methanol has positive effects on gasoline combustion, and ethanol can rapidly ignite the gasoline in a wide range of operating conditions and is superior to methanol in terms of fuel combustion, stability, and pollutant discharge. Based on the treatment of simulated values of six combustion characteristics selected in this paper and the calculations of the variation disturbance method, the total disturbance values of ethanol and methanol to gasoline combustion are obtained as 0.8493 and 0.2605, respectively. That is, ethanol has a more significant effect on improving the combustion performance of gasoline than methanol. In addition, based on the analysis results of the combustion, it is found that the blending of ethanol enlarges the reaction of notable components in gasoline. This finding also proves the effectiveness and validity of the scientific method utilized in this paper.

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