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We propose an optically clocked transistor array optoelectronic integrated circuit (OEIC) for both serial-to-parallel and parallel-to-serial conversion (demux/mux), enabling an interface between high-speed asynchronous burst optical labels and CMOS circuitry for optical label swapping. Dual functionality of the OEIC reduces size, power, and cost of the optical label swapper. The capability for greater than 20-Gb/s conversion operation is demonstrated.  相似文献   
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The impact of crosstalk in an arrayed-waveguide N×N wavelength multiplexer is investigated precisely in relation to its application to wavelength-routing N×N all optical networks. In such systems multiple crosstalk light which has the same wavelength as the signal results in signal-crosstalk beat noise. We confirm that the noise is Gaussian and obtain the relation between crosstalk and power penalty. It is shown that the crosstalk must be less than -38 dB for a 16×16 system to keep the power penalty below 1 dB at a bit error rate of 10-9  相似文献   
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Two novel configurations for digitally tunable optical filters based on arrayed-waveguide grating (AWG) multiplexers are described in detail with emphasis on the connection of the AWG multiplexer and optical switches. Performance comparisons show that conventional configurations are disadvantaged by the switch size required and loss imbalance among the optical frequency-division-multiplexed (FDM) channels; the proposed configurations require only O(√(N)) switch elements to select one of N FDM channels, and the loss imbalance is lower by up to 75% in decibel  相似文献   
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Specimens of partially stabilized zirconia were slip cast from aqueous suspensions and sintered at 1500°C for 3 h. The relative density of the cast specimens and the firing shrinkage of the sintered specimens depend on the milling time for the suspension. Vickers hardness and KIC values of 11.46±s0.07 GN/m2 and 6.10 ±0.04 MN.m3/2, respectively, were obtained for all sintered specimens. The dispersion of the suspension is important in increasing the relative density of the cast specimens.  相似文献   
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BACKGROUND: The biotransformation of sesquiterpenoids, which are a large class of naturally occurring compounds, using microorganisms as a biocatalyst to produce useful novel organic compounds was investigated. The biotransformation of sesquiterpenoids, (+)‐aromadendrene ( 1 ), (−)‐alloaromadendrene ( 2 ) and (+)‐ledene ( 3 ) has been investigated using Aspergillus wentii as a biocatalyst. Results: Compound 1 was converted to (−)‐(10S,11S)‐10,13,14‐trihydroxyaromadendrane ( 4 ). Compound 2 was converted to (+)‐(1S,11S)‐1,13‐dihydroxyaromadendrene ( 5 ) and (−)‐5,11‐epoxycadin‐1(10)‐en‐14‐ol ( 6 ). Compound 3 was converted to compound 6 , (+)‐(10R,11S)‐10,13‐dihydroxyaromadendr‐1‐ene ( 7 ) and (+)‐(10S,11S)‐10,13‐dihydroxyaromadendr‐1‐ene ( 8 ). The structure of the metabolic products has been elucidated on the basis of their spectral data. CONCLUSION: Compound 1 gave only one product that was hydroxylated at C‐10, C‐13 and C‐14. By contrast, compounds 2 and 3 gave a number of products, one of which was common. The differences in oxidation of 1–3 are due to the configuration of the C‐1 position. Compounds 4–8 were new compounds. Copyright © 2008 Society of Chemical Industry  相似文献   
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ABSTRACT Postmortem structural changes in titin and nebulin filaments were investigated by incubating isolated myofibrils in a solution containing 0.1 mM calcium ions and various concentrations of a protease inhibitor. The inhibition curves showed 2 abnormal steps with increases in the concentration of leupeptin or calpastatin domain I. While the amounts of unchanged titin and nebulin were constant in the 1st step, the 2nd occurred at higher protease inhibitor concentrations. These facts indicated that excess amounts of leupeptin and calpastatin domain I caused deterioration in titin and nebulin properties, thus interfering with the binding of calcium ions. We concluded that the severance of titin and nebulin filaments in the 1st step were induced by calcium ions at 0.1 mM.  相似文献   
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The iron status of 22 children and adolescents with Crohn's disease (mean age: 13 years) was evaluated. Eleven patients were suffering from active disease with inflammation, identified by at least one abnormal value for serum orosomucoid, C-reactive protein or sedimentation rate (group I). Eleven patients were in clinical remission and showed no biological evidence of inflammation (group II). Hemoglobin and red cell indices, erythrocyte protoporphyrin, serum iron, transferrin, serum ferritin and basic red cell ferritin were determined in all patients. The usual indicators of iron status, particularly serum ferritin, were affected by the inflammatory processes, but basic red cell ferritin appeared to be independent of inflammation. Basic red cell ferritin can therefore be considered to be a reliable indicator of iron status in children and adolescents with Crohn's disease.  相似文献   
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