A high-efficiency blue-emitting organic light-emitting diode (OLED) approaching theoretical efficiency using an exciplex-forming co-host composed of N,N'-dicarbazolyl-3,5-benzene (mCP) and bis-4,6-(3,5-di-3-pyridylphenyl)- 2-methylpyrimidine (B3PYMPM) is fabricated. Iridium(III)bis[(4,6-difluorophenyl)- pyridinato-N,C2']picolinate (FIrpic) is used as the emitter, which turns out to have a preferred horizontal dipole orientation in the emitting layer. The OLED shows a maximum external quantum efficiency of 29.5% (a maximum current efficiency of 62.2 cd A(-1) ), which is in perfect agreement with the theoretical prediction.

Metformin is the first pharmacological option for treating type 2 diabetes. However, the use of this drug is not recommended in individuals with impaired kidney function because of the perceived risk of lactic acidosis. We aimed to assess the efficacy and safety of metformin in patients with type 2 diabetic kidney disease (DKD). RESEARCH DESIGN AND METHODSWe conducted a retrospective observational cohort study of 10,426 patients with type 2 DKD from two tertiary hospitals. The primary outcomes were all-cause mortality and end-stage renal disease (ESRD) progression. The secondary outcome was metformin-associated lactic acidosis. Taking into account the possibility that patients with less severe disease were prescribed metformin, propensity score matching (PSM) was conducted. RESULTSAll-cause mortality and incident ESRD were lower in the metformin group according to the multivariate Cox analysis. Because the two groups had significantly different baseline characteristics, PSM was performed. After matching, metformin usage was still associated with lower all-cause mortality (adjusted hazard ratio [aHR] 0.65; 95% CI 0.57-0.73; P < 0.001) and ESRD progression (aHR 0.67; 95% CI 0.58-0.77; P < 0.001). Only one event of metformin-associated lactic acidosis was recorded. In both the original and PSM groups, metformin usage did not increase the risk of lactic acidosis events from all causes (aHR 0.92; 95% CI 0.668-1.276; P 5 0.629). CONCLUSIONSIn the present retrospective study, metformin usage in advanced chronic kidney disease (CKD) patients, especially those with CKD 3B, decreased the risk of all-cause mortality and incident ESRD. Additionally, metformin did not increase the risk of lactic acidosis. However, considering the remaining biases even after PSM, further randomized controlled trials are needed to change real-world practice.Diabetes is the leading cause of chronic kidney disease (CKD) (1,2). According to the American Diabetes Association care guidelines, metformin is considered a first-line treatment for type 2 diabetes because of its efficacy, low cost, weight neutrality, and benefits regarding cardiovascular outcomes (3-5). In patients with CKD, however, the use of metformin is not recommended due to the risk of lactic acidosis (6,7).The risk of lactic acidosis and its fatal consequences have resulted in the withdrawal of biguanide, phenformin and buformin, from the market (8,9). However, decades of clinical experience have provided clinicians with insights into the low incidence of

The rate-limiting step of charge generation in charge-generation units (CGUs) composed of a p-doped hole-transporting layer (p-HTL), 1,4,5,8,9,11-hexaazatriphenylene hexacarbonitrile (HATCN) and n-doped electron-transporting layer (n-ETL), where 1,1-bis-(4-bis(4-methyl-phenyl)-amino-phenyl)-cyclohexane (TAPC) was used as the HTL is reported. Energy level alignment determined by the capacitance-voltage (C-V) measurements and the current density-voltage characteristics of the structure clearly show that the electron injection at the HATCN/n-ETL junction limits the charge generation in the CGUs rather than charge generation itself at the p-HTL/HATCN junction. Consequently, the CGUs with 30 mol% Rb 2 CO 3 -doped 4,7-diphenyl-1,10-phenanthroline (BPhen) formed with the HATCN layer generates charges very efficiently and the excess voltage required to generate the current density of ±10 mA cm −2 is around 0.17 V, which is extremely small compared with the literature values reported to date.

Lim et al e405 FIGURE 1. Flow diagram of the study participants. SGLTi, sodium-glucose cotransporter 2 inhibitors.