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  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 91 (2002), S. 4637-4645 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: A method for evaluating localized grain boundary (GB) trap states in polycrystalline–silicon thin-film transistors (poly-Si TFTs) is proposed. Field effects in poly-Si TFTs are analyzed by decomposition of the two-dimensional Poisson's equation. This analysis gives the theoretical basis for evaluating the localized GB trap state density. The trap states are evaluated with the GB barrier potential given by the activation energy of the effective mobility and with the surface potential calculated from the capacitance–voltage characteristics in poly-Si TFTs. This evaluating method was applied to several different types of poly-Si TFTs fabricated with excimer laser annealing crystallization processes. This method has succeeded experimentally in eliminating the error effects related to oxide–semiconductor interface trap states and in clarifying that the GB barrier potential has a peak in its gate bias dependence. This method has also elucidated that the GB trap state density has almost the same value independent of the grain size when the hydrogenation efficiency in poly-Si is in the same level between TFTs. The good agreement of the simulated and the measured drain currents confirm the validity of this method. © 2002 American Institute of Physics.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 56 (1990), S. 411-413 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Retinal derivatives were synthesized and their third-order nonlinear optical properties were measured by degenerate four-wave mixing with temporally incoherent nanosecond laser pulses. Fast optical nonlinearities, whose response time was shorter than 30 ps, were observed. The magnitudes of resonant third-order hyperpolarizability were found to be 10−31∼10−29 esu. The large optical nonlinearities were of electronic origin.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 78 (2001), S. 3259-3261 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Photon-induced current (Iph) in polycrystalline-silicon thin-film transistors (poly-Si TFTs) has been investigated using a line-shaped light beam scanning method. In the off-state region, photon-excited carriers in the channel region diffuse to the drain with the diffusion length independent of the poly-Si grain size. The diffusion length is also independent whether poly-Si is hydrogenated or not. This phenomenon is observed in both n-channel and p-channel TFTs. In the subthreshold region, Iph follows the general transport equation in poly-Si. In the inversion region, Iph is proportional only to the total amount of excited carriers in the channel. © 2001 American Institute of Physics.
    Materialart: Digitale Medien
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  • 4
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 63 (1993), S. 2463-2465 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Resonant nonlinear optical response was measured in a crystalline cyanine dye MPER, 5-(5-morpholino-2,4-pentadienilydene)-3-ethylrhodanine, which had a broad reflection band due to large oscillator strength of an electronic excited state in the visible wavelength region. Nonlinear optical response measured by the change of reflectivity under optical pumping at the wavelength of the peak of the excited state was composed of fast and slow components. Response time of the fast component was less than 4 ps and its nonlinear optical coefficient χ(3) was evaluated to be (5±2)×10−15 m2/V2 [(4±2)×10−7 esu], which was one of the largest among organic materials.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 16 (1969), S. 0 
    ISSN: 1471-4159
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: The levels of certain amines (catecholamines, 5-HT, and ‘histamine’) and of certain enzymes (tyrosine hydroxylase, tryptophan hydroxylase, ChAc, or AChE) in whole brain or selected brain areas of rats and mice susceptible to audiogenic seizure have been compared with the levels in matched groups of non-sensitive animals. Sensitive groups included both those where susceptibility is inborn and those where it is induced by administration of methionine sulphoximine or thiosemicarbazide. No significant difference was found which could be correlated with susceptibility to audiogenic seizure.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Genetics 2 (1968), S. 245-278 
    ISSN: 0066-4197
    Quelle: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Thema: Biologie
    Materialart: Digitale Medien
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  • 7
    Digitale Medien
    Digitale Medien
    Oxford, UK : Blackwell Science Ltd
    Weed research 43 (2003), S. 0 
    ISSN: 1365-3180
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Summary The effects of simulated human trampling on leaf morphology and ethylene production as well as the effect of an ethylene releaser ethephon on leaf morphology were investigated for trampling-tolerant species, Plantago asiatica and Eleusine indica, and trampling-susceptible species, Gnaphalium affine and Panicum bisulcatum. In Pl. asiatica, trampling decreased the leaf length and increased the leaf blade length to width ratio and the leaf blade length to leaf (leaf blade + petiole) length ratio. In E. indica, trampling only decreased the leaf blade length to width ratio. Trampling increased ethylene production in intact seedlings of Pl. asiatica, E. indica and G. affine. The ethephon (1 mM) treatment increased the leaf blade length to width ratio in seedlings of Pl. asiatica, but decreased that in seedlings of E. indica in a manner similar to the morphological changes induced by trampling. In contrast, no significant differences in leaf morphology were observed between the ethephon-treated and control seedlings of trampling-susceptible species. These results suggest that trampling-tolerant species have higher responsiveness to ethylene than trampling-susceptible species and change their leaf morphology in response to ethylene induced by trampling.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    Springer
    Neuroradiology 36 (1994), S. 298-302 
    ISSN: 1432-1920
    Schlagwort(e): Pituitary adenoma ; MRI ; Immunohistochemistry ; Pituitary hormones
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Our aim was to elucidate the factors which determine the MRI signal intensities of pituitary adenomas. We examined 51 patients with surgically-confirmed pituitary adenomas. Using a spin-echo pulse sequence (SE 500/15), coronal and sagittal images (3 mm slices) were obtained. Signal intensities on T1-weighted images were measured in the parenchyma of the adenoma and in normal grey matter. The relative intensity of the adenoma was assessed by calculating the ratio of its signal intensity to that of the normal grey matter of the same patient. Parafin-embedded sections were used for haematoxylin and eosin staining. The number of cells in a prescribed area was counted, and the mean of five such counts was taken as the cell density. Immunohistochemically stained sections using antibodies for various pituitary hormones were similarly examined; the ratio of the total number of hormone-positive cells to the overall total number of adenoma cells was calculated. Four independent variables were used in the analysis: the age of the patient, the maximum diameter of the adenoma, the cell density and the proportion of hormone-positive cells in the adenoma and, with the signal intensity ratio as the dependent variable, a multiple regression analysis was performed. This revealed that the the greatest influence upon the signal intensities on T1-weighted images was the proportion of hormone positive cells.
    Materialart: Digitale Medien
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  • 9
    ISSN: 1432-1750
    Schlagwort(e): Guinea pig ; Ozone ; Cigarette smoke ; Airway hyper-responsiveness ; Vascular permeability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract The effects of combined exposure to ozone and cigarette smoke on airway responsiveness and tracheal vascular permeability, compared with those of single exposure were examined in guinea pigs. Airway responsiveness was assessed by measuring the specific airway resistance (sRaw) as a function of increasing concentration of inhaled methacholine aerosol immediately, 5 hr, and 24 hr after exposure. In a parallel study, tracheal vascular permeability was quantified by measuring the tracheal extravasation of intravenously administered Evans blue dye. Neither exposure to 1 ppm ozone for 30 min nor 5 puffs of cigarette smoke increased airway responsiveness or vascular permeability at any time after exposure. Combined exposure to 1 ppm ozone for 30 min and 5 puffs of cigarette smoke caused airway hyperresponsiveness and increased vascular permeability immediately after exposure. Exposure to 1 ppm ozone for 90 min increased both airway responsiveness and vascular permeability immediately after exposure. Exposure to 10 puffs of cigarette smoke increased airway responsiveness but not vascular permeability immediately after exposure. Combined exposure to 1 ppm ozone for 90 min and 10 puffs of cigarette smoke increased both airway responsiveness and vascular permeability immediately after exposure. The combined exposure to ozone and cigarette smoke thus increased both airway responsiveness and tracheal vascular permeability to a greater extent than did exposure to a single agent, suggesting that a combination of air pollutants has a more deleterious effect both on airway responsiveness and on tracheal vascular permeability than does either agent alone in guinea pigs.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Acta neuropathologica 83 (1992), S. 361-364 
    ISSN: 1432-0533
    Schlagwort(e): c-myc protein ; Bromodeoxyuridine ; Pituitary adenoma ; Malignancy ; Labeling index
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary To clarify the relationship between the percentage of c-myc protein-labeled cells, the bromodeo-xyuridine (BrdUrd) labeling index (LI) and clinical malignancy in pituitary adenomas, we studied 31 cases of pituitary adenomas. Tumor invasiveness, recurrence, tumor size and the length of illness were evaluated from operative findings, magnetic resonance imaging findings, and the clinical course. Each pituitary adenoma was scored to represent the degree of clinical malignancy. An hour before excision of the tumor, we administered BrdUrd intravenously. Surgical materials were fixed in 70% alcohol and embedded in paraffin. Both hematoxylin and eosin staining and immunohistochemical staining were performed using a monoclonal antibody for both anti-BrdUrd and anti-c-myc protein. Among pituitary adenomas, there was a significantly low percentage of c-myc protein-labeled cells in cases with acromegaly. The percentage of c-myc protein-labeled cells in the pituitary adenomas tended to increase with increase with the total scores of clinical malignancy. The BrdUrd LI was lower than 1% in almost all cases of pituitary adenomas, and it showed no correlation with their clinical malignancy. In conclusion, determination of the percentage of c-myc protein-labeled cells in pituitary adenomas proved to be useful for evaluating their clinical malignancy.
    Materialart: Digitale Medien
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