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由于LCD显示器在色彩还原的准确性、黑色级数上都和传统CRT显示器有较大差距，且采用背光管照亮屏幕的设计，使得深黑色在LCD上一直难以实现完美还原。现在，一家名为eCinema Systems的公司宣布他们在LCD色彩技术上已经取得了重大突破。当然，几大液晶面板厂商也将会跟进，今后LCD全面取代CRT已是必然之势。     

Effect of vomeronasal organ removal from male mice on their preference for and neural Fos responses to female urinary odors.

Four experiments were conducted to determine whether vomeronasal organ (VNO) inputs in male mice mediate the rewarding properties of estrous female urinary odors. Sexually naive male mice with either an intact (VNOi) or lesioned (VNOx) VNO preferred to investigate female urine over water in Y-maze tests. Subsequently, VNOi males ran significantly more quickly and remained in nasal contact longer with estrous female urine than with male urine, whereas VNOx males investigated these odors equally. In home-cage habituation-dishabituation tests, VNOi males also investigated female urine significantly longer than did VNOx males, although both groups investigated female urine longer than other non-body odors. Finally, female urinary odors induced Fos in the nucleus accumbens core of VNOi males but not of VNOx males. Our results suggest that female urinary odors retain some incentive value in VNOx males. However, once direct nasal contact is made with female urine, VNO inputs further activate forebrain mechanisms that amplify the reward salience of this stimulus for the male mouse. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The prevalence and reliability of visibility aid and other risk factor data for uninjured cyclists and pedestrians in Edmonton, Alberta, Canada

This study was conducted to determine the prevalence and reliability of risk factors collected on uninjured cyclists-pedestrians in Edmonton, Alberta, and what characteristics predict cyclist-pedestrian visibility. At randomly selected locations from July 2004 to August 2004, two independent observers recorded cyclist-pedestrian characteristics such as age, sex, clothing color, use of reflectors, flags, helmets, and a subjective impression of visibility. Data were collected on 836 individuals; most were either walking/jogging (approximately 63%) or cycling (approximately 33%). For non-cyclists, the prevalence of bright colored clothing on the trunk ranged from 12.7 to 14.7%. Few people used any kind of reflective strips. Inter-observer agreement (Kappa) ranged from 0.37 (visibility assessment) to 0.99 (sex). For cyclists, 17-19% of headgear was brightly colored, and 13-14% was white. Approximately one-fourth had a front light; half had a rear reflector. Few cyclists used a flag and just over half used spoke reflectors. Kappa ranged from 0.35 (observer assessed speed) to 0.95 (head gear and sex). A major trunk color of orange, red, yellow or white resulted in a higher visibility rating for both cyclists and pedestrians. The results indicate a low prevalence of visibility aid use among cyclists and pedestrians, but there appears to be acceptable inter-observer reliability for most data collected. Further work is required before an overall visibility rating can be used in place of component scores.     

Effects of garlic compounds diallyl sulfide and diallyl disulfide on arylamine N-acetyltransferase activity in strains of Helicobacter pylori from peptic ulcer patients

Arylamine N-acctyltransferase (NAT) activities with p-aminobenzoic acid (PABA) and 2-aminofluorene (2-AF) were determined in the bacterium Helicobacter pylori collected from peptic ulcer patients. Two assay systems were performed, one with cellular cytosols, the other with intact cell suspensions. Cytosols or suspensions of H. pylori with or without specific concentrations of diallyl sulfide (DAS) or diallyl disulfide (DADS) co-treatment showed different percentages of 2-AF and PABA acetylation. The data indicated that there was decreased NAT activity associated with increased levels of DAS or DADS in H. pylori cytosols and suspensions. Viability studies on H. pylori demonstrated that DAS or DADS elicited dose-dependent bactericide affects on H. pylori cultures. The data also indicated that DAS and DADS decreased the apparent values of K(m) and Vmax of NAT enzyme from H. pylori in both systems examined. This report is the first demonstration that garlic components can affect H. pylori growth and NAT activity.     

PET Performance Evaluation of an MR-Compatible PET Insert

A magnetic resonance (MR) compatible positron emission tomography (PET) insert has been developed in our laboratory for simultaneous small animal PET/MR imaging. This system is based on lutetium oxyorthosilicate (LSO) scintillator arrays with position-sensitive avalanche photodiode (PSAPD) photodetectors. The PET performance of this insert has been measured. The average reconstructed image spatial resolution was 1.51 mm. The sensitivity at the center of the field of view (CFOV) was 0.35%, which is comparable to the simulation predictions of 0.40%. The average photopeak energy resolution was 25%. The scatter fraction inside the MRI scanner with a line source was 12% (with a mouse-sized phantom and standard 35 mm Bruker 1H RF coil), 7% (with RF coil only) and 5% (without phantom or RF coil) for an energy window of 350-650 keV. The front-end electronics had a dead time of 390 ns, and a trigger extension dead time of 7.32 μs that degraded counting rate performance for injected doses above ~0.75 mCi (28 MBq). The peak noise-equivalent count rate (NECR) of 1.27 kcps was achieved at 290 μCi (10.7 MBq). The system showed good imaging performance inside a 7-T animal MRI system; however improvements in data acquisition electronics and reduction of the coincidence timing window are needed to realize improved NECR performance.     

ELECTRIC ANNEALING OF GLASS*

The total and distribution heat requirements are discussed in general as well as the manner in which electric leers economically meet these requirements based on actual determinations and calculations.     

1.6 Composition and stress state of thin films deposited by ion beam sputtering

The ion beam sputtering technique offers several advantages over conventional sputtering systems. This technique operates at a lower pressure and substrate temperature than conventional sputtering. In addition, the angle of deposition which is easily varied with ion beam sputtering is essentially fixed in dc and rf diode sputtering. As a result of these advantages, many of the parameters which effect film stress, resistivity, and grain size can be varied independently.Several properties of ion beam sputtered Ni, Al, Ni₃Al and Au thin films have been evaluated as a function of ion beam current density, target material, and the angle and distance of the substrate from the target.The grain size and stress were found to vary with the angle of deposition. There is an apparent correlation between electrical resistivity and the oxygen content in the films. Both properties depend upon the grain size. The stress levels of the films are shown to be influenced by the oxygen content. These experimental results are discussed in light of models proposed to explain the origin of stress in thin films.     

Gemfibrozil significantly lowers cynomolgus monkey plasma lipoprotein[a]-protein and liver apolipoprotein[a] mRNA levels

Eight male cynomolgus monkeys (Macaca fascicularis) on a normal chow diet were orally administered gemfibrozil daily using a weekly rising dose protocol for 3 weeks (50, 125, and 200 mg/kg per day). At these drug doses, Lp[a] levels were reduced: 83.7% +/- 3.2 (SEM), (P < 0.024); 63.7% +/- 4.1 (P < 0.013); and 36.2% +/- 1.1 (P < 0.002), respectively, of pretreatment values. Lp[a] reduction was directly related to blood gemfibrozil concentration (range 36-428 microM, r = 0.969) and occurred without concomitant changes in apolipoprotein B. Three weeks posttreatment Lp[a] levels returned to pretreatment values. A specific ribonuclease protection assay demonstrated that liver apolipoprotein[a] (apo[a]) mRNA expression was decreased in all animals to an average of 19.1% +/- 3.0 (P < 0.0026), of pretreatment values after the 200 mg/kg treatment, whereas, albumin, apolipoprotein A-I, apolipoprotein E, and glyceraldehyde-3-phosphate dehydrogenase mRNAs were unchanged. Lp[a] levels were unaffected by gemfibrozil in HepG2 cells permanently transfected with an apo[a] 10-kringle cDNA construct containing partial 5'- and 3'-untranslated sequences and under control of a constitutive CMV promoter. However, both Lp[a] and apo[a] mRNA in primary cynomolgus monkey hepatocytes were coordinately lowered in a dose-dependent fashion by gemfibrozil. Thus, Lp[a] can be regulated by gemfibrozil at the level of apo[a] mRNA expression.     

Microleakage of new dentin bonding systems using human and bovine teeth

The objective of this study was twofold: to evaluate the microleakage behavior of three dentin bonding systems and to determine if bovine teeth are comparable substrates to human teeth when studying the microleakage of various materials. The materials evaluated were Scotchbond Multi-Purpose Adhesive, Prisma Universal Bond 3, and All-Bond 2. All three bonding systems were used in combination with Prisma APH hybrid composite for comparison of microleakage behavior. Sixty class 5 preparations were cut at the cementoenamel junction for groups containing 30 human and 30 bovine teeth. A 1 mm 45 degree bevel was placed at the enamel margin. Teeth were grouped according to the dentin bonding system used and then restored according to the manufacturer's directions. After restoration, the teeth from each group were stored in distilled water at 37 degrees C for 3 days. The teeth were then thermocycled between 4 degrees C and 58 degrees C for 100 cycles and returned to distilled water at 37 degrees C for an additional 4 days. The teeth were then sealed with nail polish up to 1 mm from the margins of the restoration and placed in 45Ca isotope for 2 hours. The teeth were then sectioned and placed on x-ray film to produce autoradiographs. Microleakage was evaluated for the enamel and dentin margins separately using the following scale: 0 = no leakage, 1 = penetration of isotope to less than 1/2 the distance to the axial wall, 2 = penetration of isotope greater than 1/2 of the distance to the axial wall but short of the axial wall, and 3 = penetration of isotope to the axial wall or beyond. The materials were compared to each other using the Mann-Whitney U and Kruskal-Wallis tests. The gingival margins were compared to the incisal margins for all materials. No statistically significant differences in microleakage were revealed between the incisal and gingival location for human substrates, but there was statistically significant greater gingival microleakage for bovine substrates. All-Bond 2 leaked significantly more than Scotchbond Multi-Purpose for human substrates at the incisal margin. All-Bond 2 had significantly more microleakage than Prisma Universal Bond 3 at both dentin and enamel margins for the bovine substrate. There were no statistically significant differences in microleakage among the bonding systems for the human substrate. No statistically significant differences between the microleakage behavior of human and bovine substrates were found. These results support the use of bovine teeth for in vitro microleakage studies.