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Comparison measurements on reference standards are reported in which 13 partners with different instruments took part. A set of prototype standards which had been produced and calibrated within a European project were used for the measurements. Here, results of measurements on a 240 nm step height standard and a two-dimensional lateral standard with a nominal pitch of 1 μm are reported.  相似文献   
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Glyconanoparticles which present carbohydrate and amino groups motifs at their surface were produced. These particles were highly stable and soluble in aqueous solutions. The presence of the carbohydrate groups also allowed the inclusion of more strongly binding groups, without affecting solubility. The binding of a model DNA, plasmid by these nanoparticles was studied by atomic force microscopy, transmission electron microscopy, and gel electrophoresis. Significant differences between the nanoparticles based on their affinities for the DNA were found, with implications for their potential use as nonviral gene delivery agents.  相似文献   
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The fluctuations observed by recording the picosecond pulses of a mode-locked laser with a synchroscan streak camera are due to the laser jitter and to the variations of the zero crossing of the synchronization. By means of a simple model, it is shown that the dispersions measured when the synchronization is generated from the mode-locker oscillator reflect the instantaneous time phase fluctuations of this oscillator. From the study of the experimental recordings with methods of time series analysis it results that the phase noise of the electronic oscillator is consistent with an underlying low-dimensional strange attractor.  相似文献   
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The processing costs involved in regional accent normalization were evaluated by measuring differences in lexical decision latencies for targets placed at the end of sentences with different French regional accents. Over a series of 6 experiments, the authors examined the time course of comprehension disruption by manipulating the duration and presentation conditions of accented speech. Taken together, the findings of these experiments indicate that regional accent normalization involves a short-term adjustment mechanism that develops as a certain amount of accented signal is available, resulting in a temporary perturbation in speech processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Mycobacterium simiae was the third most common mycobacterium identified over a 2-year period from a single clinical laboratory in southern Arizona. Thirty-three isolates from 25 patients were identified over 1 year. The isolation of M. simiae was considered clinically significant for only two of 23 evaluable patients. None of five patients with human immunodeficiency virus infection had clinical disease associated with M. simiae. Twenty isolates were available for detailed study. All but one of the 20 isolates were niacin-negative, and 11 were nonphotochromogenic. All 20 isolates had a triple-cluster pattern consistent with M. simiae by high-performance liquid chromatography, and restriction fragment patterns were identical for 16 isolates. Analysis of 16S rDNA confirmed the identity of all the tested isolates as M. simiae. In this study, M. simiae was a frequent clinical isolate but was rarely associated with disease. The organisms isolated were confirmed to be M. simiae but appeared to be phenotypically distinct strains of low virulence.  相似文献   
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Machine Translation - Existing work on the animation of signing avatars often relies on pure procedural techniques or on the playback of Motion Capture (MoCap) data. While the first solution...  相似文献   
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