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51.
We report what we believe to be the first experimental demonstration of coherent beam combining of two fiber amplifiers in a 100 ns pulse regime using a signal leak between the pulses. Pulses of ~100 W stimulated-Brillouin-scattering limited peak power are combined with 95% efficiency, a residual phase error of λ/27, and no significant beam quality degradation.  相似文献   
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Small libraries of di-, tri-, and tetragalactosyl clusters were efficiently synthesized using combinatorial methodology, on solid support, by click chemistry assisted by microwaves, starting from different poly alkyne DNA-based scaffolds and two galactosyl azide derivatives. The scaffold was synthesized by standard DNA solid-supported phosphoramidite chemistry using a novel alkyne phosphoramidite and an alkyne solid support. The proportion of each glycocluster in a library was modulated using different molar ratios of both galactose azides.  相似文献   
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Strong Traces for Solutions to Scalar Conservation Laws with General Flux   总被引:1,自引:0,他引:1  
In this paper we consider bounded weak solutions u of scalar conservation laws, not necessarily of class BV, defined in a subset . We define a strong notion of trace at the boundary of reached by L 1 convergence for a large class of functionals of u, G(u). The functionals G depend on the flux function of the conservation law and on the boundary of . The result holds for a general flux function and a general subset.  相似文献   
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In this article we present a Ladyženskaja–Prodi–Serrin Criteria for regularity of solutions for the Navier–Stokes equation in three dimensions which incorporates weak L p norms in the space variables and log improvement in the time variable.  相似文献   
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Abstract

A general overview of the R&D activity in fiber optic sensing developed over the last fifteen years in Portugal is given. Different topics are addressed, including interferometric, intensity and Bragg grating based fiber optic sensors, signal processing and multiplexing techniques, optical current sensors, together with some references to field trials and applications. Possible guidelines for present and future national R&D activity on this subject are outlined.  相似文献   
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Cytochrome P450 (CYP) is a family of enzymes responsible for organism detoxification. However, some of the members of the CYP1A subfamily also catalyse the activation of heterocyclic amines (HAs), present in cooked meat, to carcinogenic compounds which have been shown to increase the risk of breast, colorectal and lung cancer. In humans, CYP1A2 is the enzyme with the most significant action in HA metabolism but in rodents CYP1A1 is also important in this biotransformation. Understanding the metabolic action of these enzymes is essential to predict the factors that enable the formation of the carcinogenic products. We have built two models of CYP1A2, one for the human enzyme and one for the rat homologue. The templates chosen include the only X-ray structure published to date for a mammal CYP, a quimeric C2A5 from rabbit, as well as CYPs belonging to Bacillus megaterium (CYPBm-3), Pseudomonas putida (CYPcam), Pseudomonas sp. (CYPterp), and Saccharopolyspora erythraea (CYPeryf). Two HAs, MeIQ (2-amino-3,4-dimethylimidazo[4,5-?]quinoline) and MeIQx (2-amino-3,8-dimethylimidazo[4,5-?]quinoxaline), known substrates of human and rat CYPIA2, were docked in the active site of the models, providing information regarding the different catalytic rates associated with the metabolisms in both enzymes. This is important for analysing the behaviour of animal models concerning the testing of anticancer drugs.  相似文献   
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