Theoretical verification of intermolecular hydrogen bond induced thermally activated delayed fluorescence in SOBF-OMe

Thermally activated delayed fluorescence(TADF)molecules have attracted great attention as high efficient luminescent materials.Most of TADF molecules possess small energy gap between the first singlet excited state(S_(1))and the first triplet excited state(T_(1))to favor the up-conversion from T_(1)to S_(1).In this paper,a new TADF generation mechanism is revealed based on theoretical simulation.By systematic study of the light-emitting properties of SOBF-OMe in both toluene and in aggregation state,we find that the single SOBF-OMe could not realize TADF emission due to large energy gap as well as small up-conversion rates between S_(1)and T_(1).Through analysis of dimers,we find that dimers with intermolecular hydrogen bond(H-bond)are responsible for the generation of TADF,since smaller energy gap between S_(1)and T_(1)is found and the emission wavelength is in good agreement with experimental counterpart.The emission properties of SOBF-H are also studied for comparison,which reflect the important role of H-bond.Our theoretical results agree ith experimental results well and confirm the mechanism of H-bond induced TADF.

Simulation Study of Dynamic Fault Recovery Performance of VSC-HVDC System

The fault recovery of VSC-HVDC transmission system is often influenced by many factors, such as the reactive power compensation characteristics of the inverter and the dynamic performance of DC controllers. In this paper, the PSCAD/ EMTDC simulation tool is used to study the dynamic recovery performance of VSC-HVDC system for several different var compensating devices in VSC-HVDC inverter-Fixed capacitor (FC), Static Var compensator (SVC), and Static synchronous compensator (STATCOM) when VSC-HVDC is subject to various faults, including three phase groundings, single phase grounding and three phase breakings. The result shows that the recovery process of the whole system will be slowed down due to its negative influence on the strength of AC power system with the application of SVC, while the STATCOM can improve VSC-HVDC recovery performance greatly for its advantages over other compensating devices in areas such as voltage support ability and DC power recovery.

Study on influencing factors of beta cell early stage dysfunction in pre-diabetes

Objective:To study the effects of obesity,blood lipids,age and other factors on early functional defects ofβcells in pre-diabetes.Methods:Thirty-seven IGR subjects who met the study conditions were randomly selected,and 42 T2DM subjects were used as the control group.General items such as BMI and TG were evaluated.Standard steamed bread test was used to evaluate the subjects'fasting,30 minutes,60 minutes,120 minutes,180 minutes of insulin,C-peptide secretion and peak time.HOMA-IR index and Matsuda index were used to evaluate insulin sensitivity.HOMA-βand AUCI/AUCG were used to evaluateβ-cell Function.Results:The results of BMI,TG,Matsuda index,HOMA-βand AUCI/AUCG in IGR group were higher than those in T2DM group,and HOMA-IR was lower than those in T2DM group(P<0.05).BMI and TG in IGR group were positively correlated with fasting and late phase secretion ofβcells,positively correlated with time of peak secretion ofβcells,positively correlated with HOMA-IR(P<0.05)and negatively correlated with Matsuda index(P<0.05),and age factor in IGR group was significantly correlated with HOMA-βand AUCI/AUCG.(P<0.05).After controlling for BMI and TG,age was still associated with HOMA-βand AUCI/AUCG.(P<0.05);BMI in IGR and T2DM groups were positively correlated withβ-cell HOMA-βand AUCI/AUCG functional indexes,(P<0.05);TG,late-phase insulin secretion value and peak time of insulin secretion andβ-cell secretion index AUCI/AUCG index in IGR obese group were higher than those in non-obese group(P<0.05),and insulin resistance index Matsuda was lower than those in the non-obese group.(P<0.05).Conclusion:The increase of BMI,TG and age are the important factors that affect the early function defect ofβcell in the stage of IGR,especially the correlation between BMI,TG and IGR is greater than that of T2DM,which should be the target of intervention,control and treatment in the early stage of diabetes.

Hydraulic pressure inducing renal tubular epithelial-myofibroblast transdifferentiation in vitro

Objective: The effects of hydraulic pressure on renal tubular epithelial-myofibroblast transdifferentiation (TEMT) were investigated. Methods: We applied hydraulic pressure (50 cmH2O) to normal rat kidney tubular epithelial cells (NRK52E) for different durations. Furthermore, different pressure magnitudes were applied to cells. The morphology, cytoskeleton, and expression of myofibroblastic marker protein and transforming growth factor-β1 (TGF-β1) of NRK52E cells were examined. Results: Disorganized actin filaments and formation of curling clusters in actin were seen in the cytoplasm of pressurized cells. We verified that de novo expression of α-smooth muscle actin induced by pressure, which indicated TEMT, was dependent on both the magnitude and duration of pressure. TGF-β1 expression was significantly upregulated under certain conditions, which implies that the induction of TEMT by hydraulic pressure is related with TGF-β1. Conclusion: We illustrate for the first time that hydraulic pressure can induce TEMT in a pressure magnitude- and duration-dependent manner, and that this TEMT is accompanied by TGF-β1 secretion.