3,3'-Bicarbazole-Based Host Molecules for Solution-Processed Phosphorescent OLEDs.

Solution-processed organic light-emitting diodes (OLEDs) are attractive due to their low-cost, large area displays, and lighting features. Small molecules as well as polymers can be used as host materials within the solution-processed emitting layer. Herein, we report two 3,3'-bicarbazole-based host small molecules, which possess a structural isomer relationship. 9,9'-Di-4-n-butylphenyl-9H,9'H-3,3'-bicarbazole (BCz-nBuPh) and 9,9'-di-4-t-butylphenyl-9H,9'H-3,3'-bicarbazole (BCz-tBuPh) exhibited similar optical properties within solutions but different photoluminescence within films. A solution-processed green phosphorescent OLED with the BCz-tBuPh host exhibited a high maximum current efficiency and power efficiency of 43.1 cd/A and 40.0 lm/W, respectively, compared to the device with the BCz-nBuPh host.

The Effects of Body Composition, Physical Fitness on Time of Useful Consciousness in Hypobaric Hypoxia.

INTRODUCTION: Several previous studies have reported that hypoxia accidents of fighter pilots are rarer than gravity-induced loss of consciousness and spatial disorientation; however, the risk is greater. Therefore, this study aimed to investigate the relationship between physical fitness and body composition on time of useful consciousness (TUC) in hypobaric hypoxia. MATERIALS AND METHODS: Body composition and physical fitness testing on human participants were performed; subsequently, they were exposed to hypobaric hypoxia at a simulated altitude of 25,000 ft. Cognitive testing of the participants was accomplished by having them perform arithmetic task tables until they stopped writing for a period exceeding 5 seconds, at which point, they were placed on 100% oxygen. TUC was measured from the time the participants removed their oxygen masks to the time when the oxygen masks were placed back on them. Pearson's correlation was used to determine the relationship between TUC and other variables, and multiple regression was performed to determine the independent variables that best explain the TUC. RESULTS: TUC was positively correlated with the maximum oxygen uptake, stroke volume, arteriovenous oxygen difference, and endurance (sit-up and push-up). The maximum heart rate on the ground, high altitude, body fat mass, and percent body fat were negatively correlated with TUC. A regression analysis showed that 84.5% of the TUC can be explained by body composition and physical fitness. CONCLUSIONS: Our results revealed that increased cardiorespiratory fitness and decreased body fat mass could significantly impact the TUC. Therefore, for Air Force pilots who are frequently at high altitudes and at risk for exposure to hypoxia, aerobic exercise is significant to hypoxia tolerance.

Amylase level in extrahepatic bile duct in adult patients with choledochal cyst plus anomalous pancreatico-biliary ductal union.

AIM: To investigate the relationship between pancreatic amylase in bile duct and the clinico-pathological features in adult patients with choledochal cyst and anomalous pancreatico-biliary ductal union (APBDU). METHODS: From 39 patients who underwent surgery for choledochal cyst between March 1995 and March 2003, we selected 15 adult patients who had some symptoms and were radiologically diagnosed as APBDU, and their clinico-pathological features were subsequently evaluated retrospectively. However, we could not obtain biliary amylase in all the patients because of the surgeon's slip. Therefore, we measured the amylase level in gall bladder of 10 patients and in common bile duct of 11 patients. RESULTS: Levels of amylase in common bile duct and gall bladder ranged from 11,500 to 212,000 IU/L, and the younger the patients, the higher the biliary amylase level (r = -0.982, P<0.01). Pathologically, significant correlation was found between the size of choledochal cyst and the grade of inflammation (r = 0.798, P<0.01). And, significant correlation was found between the level of amylase in gall bladder and the grade of hyperplasia. On the other hand, there was no correlation to the age of symptomatic onset or inflammatory grade (r = 0.743, P<0.05). Level of lipase was elevated from 6,000 to 159,000 IU/L in bile duct and from 14,400 to 117,000 IU/L in the gall bladder; however, there was no significant correlation with age or clinico-pathological features. CONCLUSION: The results support the notion that amylase has a particular role in the onset of symptoms, and suggest that a large amount of biliary amylase induces early onset of symptom, thereby making early diagnosis possible.