			Home About us Contact

Minimum Thickness (minimum + thickness)

Distribution by Scientific Domains

Medical Sciences	60%

Selected Abstracts

The Role of Transition Metal Oxides in Charge-Generation Layers for Stacked Organic Light-Emitting Diodes

ADVANCED FUNCTIONAL MATERIALS, Issue 11 2010
Sami Hamwi
Abstract The mechanism of charge generation in transition metal oxide (TMO)-based charge-generation layers (CGL) used in stacked organic light-emitting diodes (OLEDs) is reported upon. An interconnecting unit between two vertically stacked OLEDs, consisting of an abrupt heterointerface between a Cs2CO3 -doped 4,7-diphenyl-1,10-phenanthroline layer and a WO3 film is investigated. Minimum thicknesses are determined for these layers to allow for simultaneous operation of both sub-OLEDs in the stacked device. Luminance,current density,voltage measurements, angular dependent spectral emission characteristics, and optical device simulations lead to minimum thicknesses of the n-type doped layer and the TMO layer of 5 and 2.5,nm, respectively. Using data on interface energetic determined by ultraviolet photoelectron and inverse photoemission spectroscopy, it is shown that the actual charge generation occurs between the WO3 layer and its neighboring hole-transport material, 4,4',4"-tris(N -carbazolyl)-triphenyl amine. The role of the adjacent n-type doped electron transport layer is only to facilitate electron injection from the TMO into the adjacent sub-OLED. [source]

Thickness of dentine in mesial roots of mandibular molars with different lengths

INTERNATIONAL ENDODONTIC JOURNAL, Issue 7 2010
T. S. Sauáia
Sauáia TS, Gomes BPFA, Pinheiro ET, Zaia AA, Ferraz CCR, Souza-Filho FJ, Valdrighi L. Thickness of dentine in mesial roots of mandibular molars with different lengths. International Endodontic Journal, 43, 555,559, 2010. Abstract Aim, To measure the minimum thickness of the distal (furcal) root dentine associated with the buccal and lingual canals of the mesial roots of mandibular first molars with different lengths. Methodology, The mesial roots of 285 mandibular first molars were allocated into three groups according to their length: group I , long (24.14 mm ± 0.85), group II , medium (22.10 mm ± 0.65) and group III , short (19.97 mm ± 0.75). The minimum thickness of the distal (furcal) root dentine associated with the buccal and lingual canals of the mesial roots 2 mm below the furcation was measured. The distance between the buccal and lingual canals, and the depth of concavity in the distal surface of the mesial roots were also measured. anova and Tukey,Kramer were used to test for significant differences among the groups. Results, The minimum thickness of the distal wall of the mesiobuccal canal was significantly different (P < 0.05) between group I (long) and III (short), with long teeth having the smallest mean values. No significant difference was found in the thickness of the distal wall of the mesiolingual canal among the groups studied (P > 0.05). The shortest distance between the mesiobuccal and the mesiolingual canals was observed in group III (P < 0.05). The distal (furcal) concavity was deeper in group I (P < 0.05) when compared with the other groups. Conclusion, There was a significant difference in the minimum thickness of the distal (furcal) root wall of the mesiobuccal canal of mandibular first molars 2 mm below the furcation between group I (long) and group III (short) teeth. The thinnest walls were found in the longest teeth. The deepest concavities in the distal (furcal) walls of the mesial roots were found in the longest roots. [source]

A population-based study of macular thickness in full-term children assessed with Stratus OCT: normative data and repeatability

ACTA OPHTHALMOLOGICA, Issue 7 2009
Urban Eriksson
Abstract. Purpose:, We aimed to determine normal macular thickness values, assessed with optical coherence tomography (OCT), in a population of full-term children of normal birthweight. Methods:, A total of 56 children, aged 5,16 years, randomly chosen from the population register, were examined with Stratus OCT. Only children with visual acuity < 0.2 logMAR, spherical equivalent of , 3 to + 3 D and astigmatism < 2 D were included. The fast macular map protocol was used and three examinations were performed in each eye. One eye was then randomized for further analyses. Mean values for the nine ETDRS areas, foveal minimum thickness and macular volume were calculated for 55 eyes. Coefficients of variance and intraclass correlations were calculated for each area. Results:, All children co-operated well and no child was excluded for lack of concentration. Mean ± standard deviation central macular thickness was 204 ± 19 ,m. Mean total macular volume was 7.11 ± 0.35 mm3. No correlations were found between age, gender and macular thickness. Coefficients of variance were < 2% and intraclass correlations were > 0.9 in all areas, except the foveal minimum. Conclusions:, Normal values for macular thickness in healthy full-term children were reported. As the Stratus OCT provides normal values only for adults, these data are a better alternative for comparison with children with retinal abnormalities. We concluded that OCT is suitable for examining the retina in children aged 5,16 years and has the same high level of repeatability as in adults. [source]

Retinal nerve fibre layer of perimetrically unaffected eyes of glaucoma patients: an optical coherence tomography study

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 2 2009
Stefano Da Pozzo MD PhD
Abstract Purpose:, The aim of this study is to evaluate whether optical coherence tomography (StratusOCT) may detect early changes in perimetrically unaffected (PU) fellow eyes of glaucomatous patients by assessing retinal nerve fibre layer (RNFL) thickness parameters. Methods:, Thirty-seven glaucomatous patients with unilateral field loss and 34 age-matched controls were recruited. In glaucoma patients, PU and perimetrically affected fellow eyes were analysed separately. For each group, mean values (±SD) of RNFL thickness parameters were calculated and comparisons between fellow eyes of glaucoma patients and between healthy and PU eyes of glaucoma patients conducted with paired t -test and Mann,Whitney U -test, respectively. Proportion of clock-hour sectors flagged with probability <5% or <1% was collected and differences between healthy and PU eyes were evaluated on Fisher exact test. Results:, Global (Average Thickness) and sectoral parameters (Inferior and Nasal Average), Maximum thickness,minimum thickness (Max-min), as well as 2-o'clock (nasal side) and 6-o'clock sectors resulted significantly thinner in PU eyes than in control group. Proportion of eyes with clock-hour position flagged with probability <5% or <1% was not significantly different between healthy and PU eyes. Conclusion:, Despite a standard automated perimetry within normal limits, the StratusOCT detected both localized and diffuse RNFL thinning in PU eyes of glaucoma patients. These eyes should be considered at risk of developing functional damage over time and consequently require thorough monitoring for detecting any sign of progression. [source]