Mes 2 B(p-4,4′-biphenyl-NPh(1-naphthyl)), (BNPB) a novel luminescent molecule that contains part of the well-known NPB functionality (NPB ) N, N′-di-1-naphthyl-N,N′-diphenylbenzidine) and a threecoordinate boron center has been synthesized. BNPB is a bright blue emitter with λ max (emission) ) 452 nm and a photoluminescent quantum yield of 95% in solution and 31% in the solid state. BNPB is an amorphous material and forms films readily via either solution casting or vacuum vapor deposition. A single layer EL device A with the device structure of ITO/BNPB/LiF/Al, two double-layer EL devices B and C with the device structure of ITO/NPB/BNPB/Ag for B and ITO/BNPB/Alq 3 /LiF/Al for C, and a triple-layer device D with the structure of ITO/NPB/BNPB/Alq 3 /LiF/Al have been fabricated and their performance has been evaluated. Device A produces a weak blue electroluminescence (EL). Device B produces a bright blue EL, identical to that of device A. Device C produces a green EL, typical of Alq 3 . Device D produces a broadband whitish-blue EL attributable to dual emission from the BNPB zone and the Alq 3 zone. Devices A-D demonstrate that BNPB is capable of transporting both holes and electrons in addition to being a blue emitter for EL devices.

There is disagreement about the association between missing posterior teeth and the presence of temporomandibular disorders (TMD). Here, the purpose was to investigate whether the number of missing posterior teeth, their distribution, age, and gender are associated with TMD. Seven hundred and forty-one individuals, aged 21-60 years, with missing posterior teeth, 386 with and 355 without TMD, were included. Four variables-gender, age, the number of missing posterior teeth, and the number of dental quadrants with missing posterior teeth-were analyzed with a logistic regression model. All four variables-gender (OR = 1.59, men = 1, women = 2), age (OR = 0.98), the number of missing posterior teeth (OR = 0.51), and the number of dental quadrants with missing posterior teeth (OR = 7.71)-were entered into the logistic model (P < 0.01). The results indicate that individuals who lose posterior teeth, with fewer missing posterior teeth but in more quadrants, have a higher prevalence of TMD, especially young women.