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121.
José M. Matés José M. Segura Cristina Pérez-Gómez Maite Asenjo Miguel Blanca 《Research on Chemical Intermediates》2001,27(3):297-304
Although oxidative status has been related to several pathophysiologic processes, there is not a well established connection between antioxidant defense and allergy. An imbalance of reactive oxygen species is related to inflammation in allergic diseases. Antioxidant enzymes are involved in cell detoxification. This primary antioxidant defence system might work against allergic's symptoms. In this work, arguments in favour of the potential of free radical scavengers in antioxidant therapy for allergic patients are discussed. 相似文献
122.
123.
Aurélie Alba Aurélia Schopp Anne‐Paula De Sousa Delgado Roland Cherif‐Cheikh Blanca Martín‐Vaca Didier Bourissou 《Journal of polymer science. Part A, Polymer chemistry》2010,48(4):959-965
The bis‐sulfonamide m‐C6H4(SO2NHPh)2 efficiently promotes the ring‐opening polymerization of lactide when combined with tertiary amines, such as N,N‐dimethylaminopyridine. Polylactides of controlled molecular weights (Mn up to 17,700 g mol?1) and very narrow molecular weight distributions (Mw/Mn < 1.11) are obtained under mild conditions and in a living fashion. The reaction takes place through a bifunctional mechanism involving activation of both the alcohol and the monomer. Modulation of the sulfonamide component supports cooperative dual hydrogen‐bonding of lactide involving the two (SO2NHAr) moieties. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 959–965, 2010 相似文献
124.
Antonio Blanca Pietro Caputo Alistair Sinclair Eric Vigoda 《Random Structures and Algorithms》2019,55(3):584-614
We consider spin systems with nearest‐neighbor interactions on an n‐vertex d‐dimensional cube of the integer lattice graph . We study the effects that the strong spatial mixing condition (SSM) has on the rate of convergence to equilibrium of nonlocal Markov chains. We prove that when SSM holds, the relaxation time (i.e., the inverse spectral gap) of general block dynamics is O(r), where r is the number of blocks. As a second application of our technology, it is established that SSM implies an O(1) bound for the relaxation time of the Swendsen‐Wang dynamics for the ferromagnetic Ising and Potts models. We also prove that for monotone spin systems SSM implies that the mixing time of systematic scan dynamics is . Our proofs use a variety of techniques for the analysis of Markov chains including coupling, functional analysis and linear algebra. 相似文献
125.
Nonlinear electrokinetics (EK), specifically electrophoresis of the second kind, dielectrophoresis (DEP) and electrorotation (EROT), have gained significant interest recently for their flexibility and labeless discriminant manner of operation. The current applications of these technologies are a clear advancement from what they were when first discovered, but also still show strong signs of future growth. The present review article presents a discussion of the current uses of microscale nonlinear EK technologies as analytical, sensing, and purification tools for microorganisms. The discussion is focused on some of the latest discoveries with various nonlinear EK microfluidic techniques, such as DEP particle trapping and EROT for particle assessments, for the analysis of microorganisms ranging from viruses to parasites. Along the way, special focus was given to key research articles from within the past two years to provide the most up-to-date knowledge on the current state-of-the-art within the field of microscale EK, and from there, an outlook on where the future of the field is headed is also included. 相似文献
126.
Dr. Julien Leclaire Dr. Messaoud Mazari Yuan Zhang Dr. Colin Bonduelle Dr. Olivier Thillaye du Boullay Prof. Blanca Martin‐Vaca Dr. Didier Bourissou Dr. Innocenzo De Riggi Dr. Rémy Fortrie Prof. Frédéric Fotiadu Prof. Gérard Buono Rémi Plamont Dr. Yoshihiro Kikkawa Mayuko Takahashi Dr. Masatoshi Kanesato Dr. Michel Giorgi Anita Chan Kam Shun Prof. Dr. Christian Roussel Prof. Dr. Teodor Silviu Balaban 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(34):11101-11101
127.
128.
José I. Martínez-López Héctor Moncada-Hernández Javier L. Baylon-Cardiel Sergio O. Martínez-Chapa Marco Rito-Palomares Blanca H. Lapizco-Encinas 《Analytical and bioanalytical chemistry》2009,394(1):293-302
Insulator-based dielectrophoresis (iDEP), an efficient technique with great potential for miniaturization, has been successfully
applied for the manipulation of a wide variety of bioparticles. When iDEP is applied employing direct current (DC) electric
fields, other electrokinetic transport mechanisms are present: electrophoresis and electroosmotic flow. In order to concentrate
particles, iDEP has to overcome electrokinetics. This study presents the characterization of electrokinetic flow under the
operating conditions employed with iDEP; in order to identify the optimal conditions for particle concentration employing
DC-iDEP, microparticle image velocimetry (μPIV) was employed to measure the velocity of 1-μm-diameter inert polystyrene particles
suspended inside a microchannel made from glass. Experiments were carried out by varying the properties of the suspending
medium (conductivity from 25 to 100 μS/cm and pH from 6 to 9) and the strength of the applied electric field (50–300 V/cm);
the velocities values obtained ranged from 100 to 700 μm/s. These showed that higher conductivity and lower pH values for
the suspending medium produced the lowest electrokinetic flow, improving iDEP concentration of particles, which decreases
voltage requirements. These ideal conditions for iDEP trapping (pH = 6 and σ
m = 100 μS/cm) were tested experimentally and with the aid of mathematical modeling. The μPIV measurements allowed obtaining
values for the electrokinetic mobilities of the particles and the zeta potential of the glass surface; these values were used
with a mathematical model built with COMSOL Multiphysics software in order to predict the dielectrophoretic and electrokinetic
forces exerted on the particles; the modeling results confirmed the μPIV findings. Experiments with iDEP were carried out
employing the same microparticles and a glass microchannel that contained an array of cylindrical insulating structures. By
applying DC electric fields across the insulating structures array, it was seen that the dielectrophoretic trapping was improved
when the electrokinetic force was the lowest; as predicted by μPIV measurements and the mathematical model. The results of
this study provide guidelines for the selection of optimal operating conditions for improving insulator-based dielectrophoretic
separations and have the potential to be extended to bioparticle applications.
Figure Comparison of experimental measurements and mathematical modeling of electrokinetic and dielectrophoretic effects on microparticles
相似文献
Blanca H. Lapizco-EncinasEmail: |
129.
130.
Baylon-Cardiel JL Jesús-Pérez NM Chávez-Santoscoy AV Lapizco-Encinas BH 《Lab on a chip》2010,10(23):3235-3242
Low frequency alternating current insulator-based dielectrophoresis is a novel technique that allows for highly controlled manipulation of particles. By varying the shape of an AC voltage applied across a microchannel containing an array of insulating cylindrical structures it was possible to concentrate and immobilize microparticles in bands; and then, move the bands of particles to a different location. Mathematical modeling was performed to analyze the distribution of the electric field and electric field gradient as function of the shape of the AC applied potential, employing frequencies in the 0.2-1.25 Hz range. Three different signals were tested: sinusoidal, half sinusoidal and sawtooth. Experimental results demonstrated that this novel dielectrophoretic mode allows highly controlled particle manipulation. 相似文献