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31.
Séverine Derbré Julia Gatto Aude Pelleray Laurie Coulon Denis Séraphin Pascal Richomme 《Analytical and bioanalytical chemistry》2010,398(4):1747-1758
Advanced glycation end-products (AGEs) are involved in the pathogenesis of numerous affections such as diabetes and neurological
diseases. AGEs are also implied in various changes in tissues and organs. Therefore, compounds able to break them or inhibit
their formation may be considered as potential drugs, dietary supplements, or bioactive additives. In this study, we have
developed a rapid and reliable (Z′ factor calculation) anti-AGEs activity screening based on the overall fluorescence of AGEs. This method was successfully
evaluated on known AGEs inhibitors and on a small library of natural compounds, yielding coherent results when compared with
literature data. 相似文献
32.
A common way to situate professional learning in practice is to use representations of teaching, such as videos of classroom instruction or samples of student work. Using representations of teaching, however, does not automatically lead to teacher learning. Learning in and from practice also requires supports that make such practice studyable. The authors introduce and explore the work of “making practice studyable” by analyzing a case of practice-based professional development in which the professional development designers deliberately tried to mediate participants’ learning in and from practice. From this analysis, the authors identified five categories of work that can help make practice studyable: (1) engaging the content, (2) providing insight into student thinking, (3) orienting to the instructional context, (4) providing lenses for viewing, and (5) developing a disposition of inquiry. These categories are then applied to the use of a representation of mathematics teaching in a course for preservice elementary teachers. 相似文献
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Laurie Y. Carrillo 《Journal of Quantitative Spectroscopy & Radiative Transfer》2011,112(3):412-419
A theoretical method for cylinder-to-cylinder radiative heat exchange is formulated. The method utilized was a modified version of a previously published numerical method for near-field sphere-to-sphere radiative exchange. Modifications were made to the numerical procedure to make it applicable to cylindrical geometry of nanorods. Nanorods investigated had length to diameter ratios of 3:1 and 7:1. The heat exchange of nanorods is plotted vs. gap to assess the impact of near-field radiative transfer as gap decreases. Graphical results of energy vs. nanorod radii are also presented. A nanorod-to-plane configuration is estimated utilizing a nanorod asymptotic method. The nanorod-to-nanorod method approximates a nanorod-to-plane geometric configuration when one nanorod radii is held constant, and the second nanorod radii is iteratively increased until the corresponding radiative exchange converges. 相似文献
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38.
Dr. Xavier Ragàs Laurie P. Cooper Dr. John H. White Prof. Santi Nonell Dr. Cristina Flors 《Chemphyschem》2011,12(1):161-165
Fluorescent proteins are increasingly becoming actuators in a range of cell biology techniques. One of those techniques is chromophore‐assisted laser inactivation (CALI), which is employed to specifically inactivate the function of target proteins or organelles by producing photochemical damage. CALI is achieved by the irradiation of dyes that are able to produce reactive oxygen species (ROS). The combination of CALI and the labelling specificity that fluorescent proteins provide is useful to avoid uncontrolled photodamage, although the inactivation mechanisms by ROS are dependent on the fluorescent protein and are not fully understood. Herein, we present a quantitative study of the ability of the red fluorescent protein TagRFP to produce ROS, in particular singlet oxygen (1O2). TagRFP is able to photosensitize 1O2 with an estimated quantum yield of 0.004. This is the first estimation of a quantum yield of 1O2 production value for a GFP‐like protein. We also find that TagRFP has a short triplet lifetime compared to EGFP, which reflects relatively high oxygen accessibility to the chromophore. The insight into the structural and photophysical properties of TagRFP has implications in improving fluorescent proteins for fluorescence microscopy and CALI. 相似文献
39.
Marlene Espinoza-Moraga Tania Petta Marco Vasquez-Vasquez V. Felipe Laurie Luis A.B. Moraes Leonardo Silva Santos 《Tetrahedron: Asymmetry》2010,21(16):1988-1992
β-Carboline imine reductions mediated by Saccharomyces bayanus have been described achieving moderate to good enantiomeric excesses of the amine products. The enantiomeric excesses of the bioreduction showed a dependence on the imine substituents. Compounds presenting C1–C11 aliphatic substituent groups afforded amines with an (S)-configuration, whereas C15 and higher aliphatic- and aromatic-substituted β-carboline imines achieved inversion of the configuration in the final (R)-2 amine products. Based on this data, a model for the Saccharomyces reduction is proposed. 相似文献
40.
A good robust functional should, if possible, be efficient at the model, smooth, and have a high breakdown point. M-estimators can be made efficient and Fréchet differentiable by choosing appropriate ψ-functions but they have a breakdown point of at most 1/(p + 1) in p dimensions. On the other hand, the local smoothness of known high breakdown functionals has not been investigated. It is known that Rousseeuw's minimum volume ellipsoid estimator is not differentiable and that S-estimators based on smooth functions force a trade-off between efficiency and breakdown point. However, by using a two-step M-estimator based on the minimum volume ellipsoid we show that it is possible to obtain a highly efficient, Fréchet differentiable estimator whilst still retaining the breakdown point. This result is extended to smooth S-estimators. 相似文献