Highly Efficient Luminescence from a Red Thermally Activated Delayed Fluorescence Emitter with Flexible Conformation of Ancillary Groups.

Robust scaffolds were typically applied in thermally activated delayed fluorescence (TADF) molecules to suppress the non-radiative decay, trigger the fast spin-flipping, and enhance the light out-coupling efficiency. Herein, we disclosed for the first time the positive effect of flexible conformation of ancillary groups on the photophysical properties of TADF emitter. The red TADF emitter Ph-TPA with flexible conformation demonstrated small excited-state structural distortion and low reorganization energy compared to the counterpart Mc-TPA with a rigid macrocycle. Consequently, Ph-TPA showed an excellent photoluminescent quantum yield (PLQY) of 92 % and a state-of-the-art external quantum efficiency (EQE) of 30.6 % at 630 nm. This work could deepen our understanding of structure-property relationships of organic luminophores and help us to rationalize the design of efficient TADF materials.

[Correlation between traditional Chinese medicine and reduced risk of readmission in rheumatoid arthritis patients with hypoproteinemia:a retrospective cohort study].

This study aimed to explore the correlation between traditional Chinese medicine(TCM) and reduced risk of readmission in patients having rheumatoid arthritis with hypoproteinemia(RA-H). A retrospective cohort study was conducted on 2 437 rheumatoid arthritis patients in the information system database of the First Affiliated Hospital of Anhui University of Chinese Medicine from 2014 to 2021, and 476 of them were found to have hypoproteinemia. The patients were divided into TCM users and non-TCM users by propensity score matching. Exposure was defined as the use of oral Chinese patent medicine or herbal decoction for ≥1 month. Cox regression analysis was performed to explore the risk factors of clinical indicators of rheumatoid arthritis. Additionally, the use of TCM during hospitalization was analyzed, and analysis of association rules was conducted to investigate the correlation between TCM, improvement of indicators and readmission of patients. Kaplan-Meier survival curve was plotted to compare the readmission rate of TCM users and non-TCM users. It was found the readmission rate of RA-H patients was significantly higher than that of RA patients. By propensity score matching, 232 RA-H patients were divided into TCM group(116 cases) and non-TCM group(116 cases). Compared with the conditions in the non-TCM group, the readmission rate of the TCM group was lowered(P<0.01), and the readmission rate of middle-aged and elderly patients was higher than that of young patients(P<0.01). Old age was a risk factor for readmission of RA-H patients, while TCM, albumin(ALB) and total protein(TP) were the protective factors. During hospitalization, the TCMs used for RA-H patients were mainly divided into types of activating blood and resolving stasis, relaxing sinew and dredging collaterals, clearing heat and detoxifying, and invigorating spleen and resolving dampness. The improvement of rheumatoid factor(RF), immunoglobulin G(IgG), erythrocyte sedimentation rate(ESR), C-reactive protein(CRP) and ALB was closely related to TCM. On the basis of western medicine treatment, the application of TCM could reduce the readmission rate of RA-H patients, and longer use of TCM indicated lower readmission rate.

Theoretical Study of the Gaseous Hydrolysis of NO2 in the Presence of Amines.

The effects on the hydrolysis of NO2 in the presence of methylamine and dimethylamine molecules were investigated by theoretical calculations of a series of the molecular clusters 2NO2-mH2O-CH3NH2 (m = 1-3) and 2NO2-mH2O-(CH3)2NH (m = 1, 2). With methylamine included in the clusters, the energy barrier is reduced by 3.2 kcal/mol from that with ammonia, and the corresponding products may form without an energy barrier. The results show that amines have larger effects than ammonia in promoting the hydrolysis of NO2 on thermodynamics. The additional water molecules can stabilize the transition states and the product complexes, and we infer that adding more water molecules in the reactions mainly act as solvent and promoting to form the methylamine nitrate (CH3NH3+NO3-). In addition, the interactions of CH3NH2 and (CH3)2NH on the hydration of HNO3 are also more effective than NH3, and the NH4NO3, CH3NH3NO3, and (CH3)2NH2NO3 complexes tend to form the larger aerosols with the increasing of water molecules. The equilibrium geometries, harmonic vibrational frequencies, and intensities of both HONO-CH3NH2 and HONO-NH3 complexes were investigated. Calculations predict that the binding energies of both HONO-CH3NH2 complexes are larger than HONO-NH3 complexes, and the OH stretching vibrational frequencies and intensities are most affected. The natural bond orbital analysis was performed to describe the donor-acceptor interactions on a series of complexes in the reactions 2NO2 + H2O + CH3NH2 and 2NO2 + H2O + (CH3)2NH, as well as the complexes of HONO-NH3 and HONO-CH3NH2. The results show that the interactions with amines are relatively larger, and the higher stabilization energies between CH3NH2 and HONO are found.

Theoretical Studies of the Reactions CFx H3-x COOR+Cl and CF3 COOCH3 +OH.

The mechanism and kinetics of the reactions of CF(3)COOCH(2)CH(3), CF(2)HCOOCH(3), and CF(3)COOCH(3) with Cl and OH radicals are studied using the B3LYP, MP2, BHandHLYP, and M06-2X methods with the 6-311G(d,p) basis set. The study is further refined by using the CCSD(T) and QCISD(T)/6-311++G(d,p) methods. Seven hydrogen-abstraction channels are found. All the rate constants, computed by a dual-level direct method with a small-curvature tunneling correction, are in good agreement with the experimental data. The tunneling effect is found to be important for the calculated rate constants in the low-temperature range. For the reaction of CF(3)COOCH(2)CH(3) +Cl, H-abstraction from the CH(2) group is found to be the dominant reaction channel. The standard enthalpies of formation for the species are also calculated. The Arrhenius expressions are fitted within 200-1000 K as kT(1) =8.4×10(-20) T (2.63) exp(381.28/T), kT(2) =2.95×10(-21) T (3.13) exp(-103.21/T), kT(3) =1.25×10(-23) T (3.37) exp(791.98/T), and kT(4) =4.53×10(-22) T (3.07) exp(465.00/T).

Theoretical study on the reactions of (CF3)2CFOCH3 + OH/Cl and reaction of (CF3)2CFOCHO with Cl atom.

Reactions of (CF3)2CFOCH3 and (CF3)2CFOCHO with hydroxyl radical and chlorine atom are studied at the B3LYP and BHandHLYP/6-311+G(d,p) levels along with the geometries and frequencies of all stationary points. This study is further refined by CCSD(T) and QCISD(T)/6-311+G(d,p) methods in the minimum energy paths. For the reaction (CF3)2CFOCH3 + OH, two hydrogen abstraction channels are found. The total rate constants for the reactions (CF3)2CFOCH3 + OH/Cl and (CF3)2CFOCHO + Cl are followed by means of the canonical variational transition state with the small-curvature tunneling correction. The comparison between the hydrogen abstraction rate constants by hydroxyl and chlorine atom is discussed. Calculated rate constants are in reasonable agreement with the available experiment data. The standard enthalpies of formation for the reactants, (CF3)2CFOCH3 and (CF3)2CFOCHO, and two products, (CF3)2CFOCH2 and (CF3)2CFOCO, are evaluated by a series of isodesmic reactions. The Arrhenius expressions for the title reactions are given as follows: k1= 1.08 × 10(-22) T(3.38) exp(-213.31/T), k2= 3.55 × 10(-22) T(3.61) exp(-240.26/T), and k3= 3.00 × 10 (-19) T(2.58) exp(-1294.34/T) cm(3) molecule(-1) s(-1).

Metformin use is associated with a reduced risk of cognitive impairment in adults with diabetes mellitus: A systematic review and meta-analysis.

Objective: Controversy exists regarding the impact of metformin and whether it prevents or promotes the incidence of cognitive dysfunction. This systematic review and meta-analysis were conducted to identify the effect of metformin therapy on cognitive function in patients with diabetes. Methods: Electronic databases (PubMed, EMBASE, PsycINFO, the Cochrane Library, and Web of Science) were systematically searched by two investigators from the date of inception until March 1, 2022. The study followed PRISMA guidelines. Inclusion criteria were defined according to the PECOS model. Eligible studies investigated cognitive dysfunction in metformin users compared with non-users in adults with diabetes. Only observational study designs (such as cohort, cross-section, and case-control) were included. Results: A systematic search identified 1,839 articles, of which 28 (17 cohort, 8 case-control, and 3 cross-sectional studies) were included in the meta-analysis. Metformin reduced the occurrence of cognitive impairment in patients with diabetes [unadjusted hazard ratio (HR) = 0.67, 95% CI: 0.62-0.73; adjusted hazard ratio (aHR) = 0.92, 95% CI: 0.85-0.99]. In addition, the use of metformin was associated with a decreased risk of dementia (HR = 0.64, 95% CI: 0.59-0.69; aHR = 0.90, 95% CI: 0.84-0.96), while a random-effects meta-analysis indicated no significant effect of metformin on the risk of Alzheimer's disease (AD) (HR = 0.85, 95% CI: 0.60-1.22; aHR = 1.10, 95% CI: 0.95-1.28). Conclusion: Metformin therapy decreased the occurrence risk of cognitive decline in patients with diabetes mellitus. Moreover, the use of metformin by adults with diabetes for the prevention of dementia, but not AD, is supported by the available evidence.

Triptolide inhibits cell growth and inflammatory response of fibroblast-like synoviocytes by modulating hsa-circ-0003353/microRNA-31-5p/CDK1 axis in rheumatoid arthritis.

Triptolide (TPL) is an active component derived from Tripterygium wilfordii Hook F (TwHF) with therapeutic potential for rheumatoid arthritis (RA). However, the underlying mechanism of TPL is remains under-studied. Competing endogenous RNA (ceRNA) networks may participate in the response to TPL in RA. Herein, we sought to identify a TPL response-related ceRNA axis. A circular RNA (circRNA)-microRNA (miRNA)-mRNA ceRNA axis associated with the TPL response was constructed according to our previous study. Modulatory mechanisms of the ceRNA axis were ascertained through a series of experimentations. The clinical relevance of the ceRNA axis was also determined using computational models. Here, we found that TPL had excellent clinical effect on RA and promising therapeutic efficacy in experimental animals. The ceRNA axis of hsa-circ-0003353 (circ0003353), miR-31-5p, and CDK1 was identified as a candidate biomarker for the response of RA patients to TPL. TPL inhibited the viability, proliferation, and cell cycle entry of RA-fibroblast-like synoviocytes (FLSs), as well as the production of cytokines. Overexpression of circ0003353 abolished the inhibitory effects of TPL on RA-FLSs. Mechanistically, circ0003353 sponged miR-31-5p that inversely targeted CDK1 and manipulated the p21/Cyclin B axis. Additionally, consecutive rescue experiments indicated that the inhibitory impacts of TPL on RA-FLSs were dependent on the circ0003353/miR-31-5p/CDK1 axis. Molecular docking was also applied to predict the specific binding sites and binding capacity of TPL to related targets. In conclusion, the present study demonstrated that TPL repressed the cell growth and inflammatory response of RA-FLSs by mediating the expression of the circ0003353/miR-31-5p/CDK1 axis. This novel ceRNA axis may serve as a biomarker for screening RA patients who respond to TPL treatment, which holds potential applications in the diagnosis and therapy of RA.

Involvement of 5-HT1A receptor-mediated histone acetylation in the regulation of depression.

Depression is one of the most common and disabling mental disorders. There is growing evidence that 5-HT1A receptor is involved in the regulation of depressive-related behaviors. However, the exact mechanism underlying the role of 5-HT1A receptor in depression remains unknown. Histone acetylation is associated with the pathophysiology and treatment of depression. In the current study, we investigated whether the epigenetic histone deacetylase (HDAC)-induced histone acetylation mediates the regulation of 5-HT1A receptor in depressive behaviors. We showed that 5-HT1A receptor selective agonist (±)-8-hydroxy-2-(dipropylamino) tetralin hydrobromide led to significant increase in acetylation of H3 at lysine 9 (Ac-H3K9) and H4 at lysine 5 (Ac-H4K5) and lysine 12 (Ac-H4K12) with obviously decreasing histone deacetylase 1 (HDAC1), histone deacetylase 2 (HDAC2), histone deacetylase 4 (HDAC4) and histone deacetylase 5 (HDAC5) expression in hippocampus of mice. Conversely, 5-HT1A receptor selective antagonist NAN-190 decreased the level of acetylation of H3 and H4 with increasing the expression of HDAC1, HDAC2, HDAC4 and HDAC5 in the hippocampus. Furthermore, we found that HDAC inhibitors, trichostatin A or suberoylanilide hydroxamic acid infusion to hippocampus prevented the depressive behaviors induced by NAN-190, as well as histone H3 and H4 acetylation in mice. Our results suggested that epigenetic histone acetylation coupled with 5-HT1A receptor may play vital role in the pathophysiology and treatment of depressive disorders.

Growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2films.

We report growth, electronic structure and superconductivity of ultrathin epitaxial CoSi2films on Si (111). At low coverages, preferred islands with 2, 5 and 6 monolayers height develop, which agrees well with the surface energy calculation. We observe clear quantum well states as a result of electronic confinement and their dispersion agrees well with density functional theory calculations, indicating weak correlation effect despite strong contributions from Co 3delectrons.Ex situtransport measurements show that superconductivity persists down to at least 10 monolayers, with reducedTcbut largely enhanced upper critical field. Our study opens up the opportunity to study the interplay between quantum confinement, interfacial symmetry breaking and superconductivity in an epitaxial silicide film, which is technologically relevant in microelectronics.

[Zero-Valent Iron (ZVI) Activation of Persulfate (PS) for Oxidation of Arsenic (â ¤) Form Aqueous Solutions].

Arsenic is one of the most toxic substances yet discovered and arsenic contamination of water has become a global environmental problem in need of a solution. This study has identified the capacity of sodium persulfate (PS), activated by zero-valent iron (ZVI) to remove As(Ⅴ) from waste-water is much greater than the capacity of PS alone due to the production of sulfate radicals in the process. Five parameter types including PS and ZVI dosage, reaction temperature, initial pH value, and initial As(Ⅴ) concentration are discussed in detail. These parameters affect the removal rate dynamics as an influencing factor of the As(Ⅴ) concentration. The material structure before and after the reaction was characterized by X-ray photoelectron spectroscopy analysis (XPS) and scanning electron microscopy (SEM). It was demonstrated that under this solution of 20-100 mg·L-1 of As(Ⅴ), the removal rate of As(Ⅴ) is more than 98% and a pseudo-second order kinetic model can be used to describe the reaction. The removal mechanism of ZVI/PS to As(Ⅴ) was explored by comparing the results of X-ray photo-electron spectroscopy of samples taken before and after reaction with ZVI/PS. PS can accelerate the corrosion of ZVI and then promote the adsorption of As(Ⅴ), moreover, it can also form precipitates and coprecipitates with iron oxide/hydroxide to achieve an enhanced removal of As(Ⅴ).

[The expression of calcium sensing receptor(CaSR) and MAPK pathway changes in myocardial cells of epilepsy rats].

OBJECTIVE: To investigate the changes of the myocardial cells in chronic epileptic rat model and to observe the expression of calcium sensing receptor(CaSR) and mitogen-activated proteinkinase(MAPK)pathway changes in epilepsy rats. METHODS: The chronic epileptic rat model was induced bypentetrazole (PTZ). Adult male Wistar rats were divided into 5 groups randomly, and there were 12 rats in each group. The rats in model group were treated with a sub-convulsivedose of PTZ (35 mg/kg) by intraperitoneal injection for 28 d. After stopping a week, the same dose of PTZ test was conducted. The control group was treated with isovolumetric saline instead of PTZ by intraperitoneal injection. According to Racine behavior grading standards the rat emerged two levels above epileptic seizure 5 consecutive times, which was considered the chronic epilepsy model successful ignition. The intervention factors included spermine(calcium-sensing receptor agonist, 3 µmol/L) and Chalhex231(calcium-sensing receptor inhibitor, 2 µmol/L). The serum creatine kinase (CK) and creatine kinase isoenzyme(CK-MB)were detected. The cardiac functions, morphological changes of rat myocardial tissue, myocardial cell ultrastructure, myocardial cell calcium sensing receptor and extracellular regulated protein kinase (ERK), p-ERK, p-JNK expression were carried out. RESULTS: Compared with normal control group, CK, CK-MB inPTZ group were increased obviously. The cardiac compliance and left ventricular function were decreased, E/A<1 by echocardiography. The myocardial ultrastructure showed serious injury. The expressions of CaSR and p-JNK were increased, but the expression of p-ERKwas decreased. Spermine could promote the expressions of CaSR and p-JNK, and decrease the expression of p-ERK in epilepsy; however, the role of Chalhex231 wasopposite. CONCLUSIONS: The level of CaSR expression increased in chronic epileptic rat model. CaSR activated the expressions of MAPK of the myocardial cells,andthen influenced the cardiac myocyte apoptosis.

Transfer-free synthesis of doped and patterned graphene films.

High-quality and wafer-scale graphene on insulating gate dielectrics is a prerequisite for graphene electronic applications. For such applications, graphene is typically synthesized and then transferred to a desirable substrate for subsequent device processing. Direct production of graphene on substrates without transfer is highly desirable for simplified device processing. However, graphene synthesis directly on substrates suitable for device applications, though highly demanded, remains unattainable and challenging. Here, we report a simple, transfer-free method capable of synthesizing graphene directly on dielectric substrates at temperatures as low as 600 °C using polycyclic aromatic hydrocarbons as the carbon source. Significantly, N-doping and patterning of graphene can be readily and concurrently achieved by this growth method. Remarkably, the graphene films directly grown on glass attained a small sheet resistance of 550 Ω/sq and a high transmittance of 91.2%. Organic light-emitting diodes (OLEDs) fabricated on N-doped graphene on glass achieved a current density of 4.0 mA/cm(2) at 8 V compared to 2.6 mA/cm(2) for OLEDs similarly fabricated on indium tin oxide (ITO)-coated glass, demonstrating that the graphene thus prepared may have potential to serve as a transparent electrode to replace ITO.

Two-dimensional optical waveguiding and luminescence vapochromic properties of 8-hydroxyquinoline zinc (Znq2) hexagonal microsheets.

Two-dimensional (2D) hexagonal microsheets of 8-hydroxyquinoline zinc (Znq2) were synthesized readily via a mixed solvent induced self-assembly method. The 2D optical waveguiding properties of the microsheets have been clearly revealed by both fluorescence microscopy and confocal microscopy. In addition, the reversible vapochromic properties of the microsheets have also been demonstrated when the Znq2 is exposed to HCl and NH3 vapors.