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71.
Dr. Meng Liu Christy Y. Hui Dr. Qiang Zhang Jimmy Gu Dr. Balamurali Kannan Dr. Sana Jahanshahi‐Anbuhi Prof. Dr. Carlos D. M. Filipe Prof. Dr. John D. Brennan Prof. Dr. Yingfu Li 《Angewandte Chemie (International ed. in English)》2016,55(8):2709-2713
We report on a paper device capable of carrying out target‐induced rolling circle amplification (RCA) to produce massive DNA amplicons that can be easily visualized. Interestingly, we observed that RCA was more proficient on paper than in solution, which we attribute to a significantly higher localized concentration of immobilized DNA. Furthermore, we have successfully engineered a fully functional paper device for sensitive DNA or microRNA detection via printing of all RCA‐enabling molecules within a polymeric sugar film formed from pullulan, which was integrated with the paper device. This encapsulation not only stabilizes the entrapped reagents at room temperature but also enables colorimetric bioassays with minimal steps. 相似文献
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Michael T. Ruggiero Dr. Juraj Sibik Dr. J. Axel Zeitler Prof. Timothy M. Korter 《Angewandte Chemie (International ed. in English)》2016,55(24):6877-6881
The rigidity of poly‐l ‐proline is an important contributor to the stability of many protein secondary structures, where it has been shown to strongly influence bulk flexibility. The experimental Young's moduli of two known poly‐l ‐proline helical forms, right‐handed all‐cis (Form I) and left‐handed all‐trans (Form II), were determined in the crystalline state by using an approach that combines terahertz time‐domain spectroscopy, X‐ray diffraction, and solid‐state density functional theory. Contrary to expectations, the helices were found to be considerably less rigid than many other natural and synthetic polymers, as well as differing greatly from each other, with Young's moduli of 4.9 and 9.6 GPa for Forms I and II, respectively. 相似文献
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On the measurement of technical efficiency in the public sector 总被引:6,自引:0,他引:6
John Ruggiero 《European Journal of Operational Research》1996,90(3):553
Existing measures of technical inefficiency obtained through linear programming models in the public sector do not properly control for environmental variables that affect production. It will be shown that the consequences of not controlling for these fixed factors are biased estimates of technical efficiency. This paper extends the mathematical programming approach to frontier estimation known as Data Envelopment Analysis to allow for environmental variables. This modified model will be then contrasted with the existing model that purportedly controls for exogeneous factors to measure public sector efficiency with simulated data. The results provide evidence that the existing Data Envelopment Analysis model will overestimate the level of technical inefficiency and that the modified model developed in this paper does a better job controlling for exogenous factors. The modified model is also applied to analyze the technical efficiency of school districts. 相似文献
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J. M. Silva E. Drigo Filho J. R. Ruggiero 《The European physical journal. E, Soft matter》2009,29(2):245-251
This paper studies energy localization conditions in lattices of the type proposed by Peyrard and Bishop. Homogeneous and
inhomogeneous lattices are analyzed and the role of interfaces in the latter is emphasized. Simulations allowed us to identify
critical energy values for the existence of localization. After a certain energy value, it is possible to observe the loss
of energy localization along the chain. 相似文献
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The first [4+2+2] cycloadditions involving terminal alkynes and diene-enes, including a fully intramolecular example, are reported resulting in the formation of cyclooctadienes using [RhCl(CO)2]2 (5 mol %) treated with AgSbF6 (10 mol %) as a precatalyst. The reaction is general for a variety of terminal alkynes, as well as variously substituted diene-enes (yields up to 88%). 相似文献