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This paper proposes a set-membership approach to characterize the kernel of an interval-valued function. In the context of a bounded-error estimation, this formulation makes it possible to embed all uncertainties of the problem inside the interval function and thus to avoid bisections with respect to all these uncertainties. To illustrate the principle of the approach, two testcases taken from robotics will be presented. The first testcase deals with the characterization of all loops of a mobile robot from proprioceptive measurements only. The second testcase is the localization of a robot from range-only measurements. 相似文献
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The gravitational Szekeres differential system is completely integrable with two rational first integrals and an additional analytical first integral. We describe the dynamics of the Szekeres system when one of these two rational first integrals is negative, showing that all the orbits come from the infinity of and go to infinity. 相似文献
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Marco Faustini David Grosso Cédric Boissière Renal Backov Clément Sanchez 《Journal of Sol-Gel Science and Technology》2014,70(2):216-226
Integrative sol–gel chemistry based strategies allow, through the strong coupling between materials chemistry and advanced processing, the fabrication of functional inorganic and hybrid materials. The following article will highlight some of the main accomplishments performed during the last years in the design of nano- and multi-scale structured materials shaped as thin films, powders and monoliths with additional functionalities and outstanding properties in several fields of application such as optics, catalysis and nanomedicine. In particular we discuss the key role played by the adapted liquid processing of sol–gel based solution. We will describe some technologies (including dip coating, spray drying, droplet-microfluidics, ink-jet and foaming) in which a high degree of control in term of liquid shaping/evaporation/manipulation is required in order to achieve specific functionalities. 相似文献
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Determination of fexofenadine in Hank's balanced salt solution by high‐performance liquid chromatography with ultraviolet detection: application to Caco‐2 cell permeability studies
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Marco Antônio dos. Reis Júnior Ana Cláudia Miranda de Faria Eudes da. Silva Velozo Teresa Dalla Costa Frank Pereira de Andrade Whocely Victor de Castro 《Biomedical chromatography : BMC》2015,29(4):537-544
The drug‐transporting proteins can affect the pharmacokinetics and pharmacodymanics of many drugs, resulting in an erratic and unpredictable pharmacological response. The Caco‐2 monolayer is routinely applied to investigate the carrier‐mediated transport of drugs. Therefore, the selection of a marker compound able to characterize the activity of such transporters is crucial. Fexofenadine (FEX), a P‐gp/OATP substrate, can be considered a suitable probe. However, in order to use be used as a marker compound, it is mandatory to develop an analytical method able to quantify this drug during the in vitro permeability assay. An HPLC method with ultraviolet detection was developed; the mobile phase consisted of phosphate buffer (pH 3.2) containing 10 m m of sodium octanosulphonate and acetonitrile (60:40) and the flow rate was set at 1.2 mL/min. Fexofenadine was eluted at 40°C, the retention time was about 4.6 min. The LOD and LOQ values were 1.9 and 6.2 ng/mL, respectively. Verapamil and ketoconazole, the most common P‐gp inhibitors, were eluted as distinct peaks of that corresponding to fexofenadine The method was successfully applied to quantify the amount of FEX transported across the Caco‐2 monolayer and could be an additional tool for those investigating the role of membrane transporters on drug absorption. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Simon Graßl Clémence Hamze Thaddäus J. Koller Prof. Dr. Paul Knochel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(15):3752-3755
(Hetero)aryl, benzylic, and alkyl zinc halides were thiolated with N-thiophthalimides at 25 °C within 1 h in the presence of 5–10 % Cu(OAc)2 ⋅ H2O to furnish the corresponding polyfunctionalized thioethers in good yields. This electrophilic thiolation was extended to the introduction of trifluoromethylthio (SCF3), thiocyanate (SCN), and selenophenyl (SePh) groups. The utility of this method was shown in a seven-step synthesis of a potent cathepsin D inhibitor in 34 % overall yield. 相似文献
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Importance of the Correlation between Width and Length in the Shape Analysis of Nanorods: Use of a 2D Size Plot To Probe Such a Correlation
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Prof. Clément Roux Dr. Céline Delmas Prof. Jean‐Daniel Marty Dr. Myrtil L. Kahn Dr. Christophe Mingotaud 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12424-12429
Analysis of nanoparticle size through a simple 2D plot is proposed in order to extract the correlation between length and width in a collection or a mixture of anisotropic particles. Compared to the usual statistics on the length associated with a second and independent statistical analysis of the width, this simple plot easily points out the various types of nanoparticles and their (an)isotropy. For each class of nano‐objects, the relationship between width and length (i.e., the strong or weak correlations between these two parameters) may suggest information concerning the nucleation/growth processes. It allows one to follow the effect on the shape and size distribution of physical or chemical processes such as simple ripening. Various electron microscopy pictures from the literature or from the authors′ own syntheses are used as examples to demonstrate the efficiency and simplicity of the proposed 2D plot combined with a multivariate analysis. 相似文献