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991.
On-chip electrophoresis can provide size separations of nucleic acids and proteins similar to more traditional slab gel electrophoresis. Lab-on-a-chip (LoaC) systems utilize on-chip electrophoresis in conjunction with sizing calibration, sensitive detection schemes, and sophisticated data analysis to achieve rapid analysis times (<120 s). This work describes the utility of LoaC systems to enable and augment systems biology investigations. RNA quality, as assessed by an RNA integrity number score, is compared to existing quality control (QC) measurements. High-throughput DNA analysis of multiplex PCR samples is used to stratify gene sets for disease discovery. Finally, the applicability of a high-throughput LoaC system for assessing protein purification is demonstrated. The improvements in workflow processes, speed of analysis, data accuracy and reproducibility, and automated data analysis are illustrated.  相似文献   
992.
A PC-controlled, scanning online UV detector for continuous free-flow electrophoresis (CFFE) was designed to allow for single UV wavelength monitoring across a 1-D array of 48 longitudinal flow cells interfaced to a CFFE apparatus. In the detection scheme, the UV light is sequentially passed through each of the flow cells. The design integrates online acquisition of absorbance spectra of components separated by CFFE. Benzoic acid standard solutions were used to examine the performance of the detector. Chloroquine diphosphate and 4-nitrophenol were used as test solutes to determine the detector's ability to distinguish analytes separated in the CFFE.  相似文献   
993.
Gold nanoparticles with diameters of ca. 13 nm were synthesised by UV irradiation of a supramolecular organogel into which HAuCl4 and tetraoctylammonium bromide had been diffused-the gel network plays an essential role in nanoparticle stabilisation.  相似文献   
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Application of modern synthetic methods to the Maitland-Japp reaction has provided a one pot, one step procedure for the efficient construction of highly substituted tetrahydropyran-4-ones.  相似文献   
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Significant wave height, , is a measure of the variability of the ocean surface and is defined to be four times the standard deviation of the height of the ocean surface. In this paper, we present a methodology for modelling estimates of over space and time, using data obtained from satellite measurements. These estimates can be thought of as a random surface in space which develops over time. For each fixed time and over some limited region in space, the field consisting of the estimates may be considered stationary. Furthermore, it is reasonable to assume that the (natural) logarithms of the estimates are normally distributed. Under these assumptions and for each fixed time, the marginal distribution over space of the random field of the logarithms of the estimates is fitted by estimating its mean and covariance function, where the form of the covariance function is chosen to allow for correlation patterns at different spatial scales in the data. Both the mean and the covariance function of this model are allowed to be time dependent. A new methodology is developed for estimating the parameters of the chosen covariance structure. The proposed model is validated along the TOPEX-Poseidon satellite tracks by computing distributions of different quantities for the fitted model and comparing these to empirical estimates. Finally, the fitted model is used to compute the distribution of the global maximum over a certain region in the North Atlantic and to reconstruct the field.The research of Anastassia Baxevani is partially supported by the Gothenburg Stochastic Center.  相似文献   
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An algorithm for assigning the members of two disjoint equal sets to each other under the criterion of Stable Marriage is analysed and the results compared to the experimental results obtained on a computer. The number of comparisons is shown to be of ordern logn (wheren is the size of the sets) which is better than that achieved by algorithms for solving the Classical Assignment Problem.  相似文献   
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