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121.
Silvère André Lydia Saint Cristau Sabine Gaillard Olivier Devos Éric Calvosa Ludovic Duponchel 《Analytica chimica acta》2015
The Food and Drug Administration's (FDA) process analytical technology (PAT) framework has been initiated to encourage drug manufacturers to develop innovative techniques in order to better understand their processes and institute high level quality control which allows action at any point in the manufacturing process. While Raman spectroscopy and chemometrics have been successfully used to predict concentration of conventional metabolites in cell cultures, it is really not the case for active substances. Thus, we propose, for the first time, an in-line and real-time prediction of recombinant antibody titer using an immersion probe link to a spectrometer without the tacking of samples. A good robustness of the method is observed on different culture batches and the contamination risk is drastically reduced which is an important issue in biotechnology manufacturing processes. 相似文献
122.
Matthieu Emond Thomas Le Saux Dr. Sylvie Maurin Jean‐Bernard Baudin Prof. Dr. Raphael Plasson Dr. Ludovic Jullien Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(29):8822-8831
This paper evaluates the 2‐hydroxyazobenzene platform for tailoring proton concentration pulses and oscillations with monochromatic light. The easily prepared 2‐hydroxyazobenzenes exhibit large absorptions in the near‐UV range. Photoisomerization was investigated by UV/Vis absorption, 1H NMR spectroscopy, and steady‐state fluorescence emission. In the whole investigated series, the trans stereoisomer of the 2‐hydroxyazobenzene motif provides the corresponding cis derivative with an action cross section in the 103 M ?1 cm?1 range. At the same time, photoisomerization is accompanied by a significant pK drop of the phenol group. According to the phenyl‐substituent pattern, cis‐to‐trans thermal back‐isomerization can be tuned in the 10 ms–100 s range. Up to 2 units of reversible pH drops or pH oscillations on the 10 s timescale have been obtained by appropriately tailoring single‐wavelength illumination of 2‐hydroxyazobenzene solutions. 相似文献
123.
Humans can be exposed to aquatic toxins mainly through contamination of food and water (drinking and recreational). Among
these toxins, contamination by both phycotoxins occurring in shellfish and cyanotoxins mostly involved in freshwater bodies
are of concern for public health. Whereas regulations exist to evaluate the genotoxicity of most compounds to which humans
are exposed, including drugs and chemicals, no regulations have been established for these compounds. In this paper, we show
that the same strategy including both in vitro and in vivo tests can be followed to evaluate the genotoxicity of aquatic toxins
(phycotoxins and cyanotoxins). However, this strategy encountered different limits which arise when completing an overview
of the genotoxic potential of toxins. The most restrictive one is undoubtedly the low amount (even the lack sometimes) of
purified toxins available. Solutions and recommendations for testing the genotoxicity of aquatic toxins are suggested to overcome
the specific problems encountered with these compounds. It must be kept in mind that recent developments in drug toxicology
should be considered and that experiments must be conducted in respect of the 3Rs principle of refinement, reduction and replacement
for animal experimentation. 相似文献
124.
Jonathan Tennyson Peter F. Bernath Alain Campargue Ludovic Daumont Joseph T. Hodges Oleg L. Polyansky Laurence S. Rothman Ann Carine Vandaele Sophie Fally Tibor Furtenbacher Shui-Ming Hu Boris A. Voronin 《Journal of Quantitative Spectroscopy & Radiative Transfer》2010,111(15):2160-1106
This is the second of a series of articles reporting critically evaluated rotational-vibrational line positions, transition intensities, pressure dependences, and energy levels, with associated critically reviewed assignments and uncertainties, for all the main isotopologues of water. This article presents energy levels and line positions of the following singly deuterated isotopologues of water: HD16O, HD17O, and HD18O. The MARVEL (measured active rotational-vibrational energy levels) procedure is used to determine the levels, the lines, and their self-consistent uncertainties for the spectral regions 0-22 708, 0-1674, and 0-12 105 cm−1 for HD16O, HD17O, and HD18O, respectively. For HD16O, 54 740 transitions were analyzed from 76 sources, the lines come from spectra recorded both at room temperature and from hot samples. These lines correspond to 36 690 distinct assignments and 8818 energy levels. For HD17O, only 485 transitions could be analyzed from three sources; the lines correspond to 162 MARVEL energy levels. For HD18O, 8729 transitions were analyzed from 11 sources and these lines correspond to 1864 energy levels. The energy levels are checked against ones determined from accurate variational nuclear motion computations employing exact kinetic energy operators. This comparison shows that the measured transitions account for about 86% of the anticipated absorbance of HD16O at 296 K and that the transitions predicted by the MARVEL energy levels account for essentially all the remaining absorbance. The extensive list of MARVEL lines and levels obtained are given in the Supplementary Material of this article, as well as in a distributed information system applied to water, W@DIS, where they can easily be retrieved. In addition, the transition and energy level information for H217O and H218O, given in the first paper of this series [Tennyson, et al. J Quant Spectr Rad Transfer 2009;110:573-96], has been updated. 相似文献
125.
Taton D Baussard JF Dupayage L Poly J Gnanou Y Ponsinet V Destarac M Mignaud C Pitois C 《Chemical communications (Cambridge, England)》2006,(18):1953-1955
Branched water-soluble copolymers were obtained by direct radical crosslinking copolymerisation of acrylic acid or acrylamide and N,N'-methylenebisacrylamide at high solid content in the presence of an O-ethylxanthate as a reversible chain transfer agent. 相似文献
126.
In glassy materials, aging proceeds at large times via thermal activation. We show that this can lead to negative dynamical response functions and novel and well-defined violations of the fluctuation-dissipation theorem, in particular, negative fluctuation-dissipation ratios. Our analysis is based on detailed theoretical and numerical results for the activated aging regime of simple kinetically constrained models. The results are relevant to a variety of physical situations, such as aging in glass formers, thermally activated domain growth, and granular compaction. 相似文献
127.
Ludovic Jean Michael Pouliquen Jérôme Blanchet Marie-Claire Lasne Jacques Rouden 《中国科学:化学(英文版)》2010,53(9):1907-1913
Enantiopure 2-(dicyclohexylphosphino)-1,1′-biphenyl derivatives substituted in the 2′-position by a chiral amino group were prepared. For the compound bearing an acyclic chiral chain, the key step was a Suzuki coupling between bromobenzeneboronic acid and N-Boc-iodoaniline whereas an aromatic nucleophilic substitution allowed the introduction of a chiral pyrrolidine in the 2′-position of the biphenyl backbone. The efficiency of the P,N-biphenyl pyrrolidine derivatives as ligands in Pd-catalyzed arylaminations compares well with that of DavePhos ligand. 相似文献
128.
Ludovic?SacchelliEmail author Mario?Sigalotti 《Calculus of Variations and Partial Differential Equations》2018,57(2):59
In this article we study the validity of the Whitney \(C^1\) extension property for horizontal curves in sub-Riemannian manifolds that satisfy a first-order Taylor expansion compatibility condition. We first consider the equiregular case, where we show that the extension property holds true whenever a suitable non-singularity property holds for the endpoint map on the Carnot groups obtained by nilpotent approximation. We then discuss the case of sub-Riemannian manifolds with singular points and we show that all step-2 manifolds satisfy the \(C^1\) extension property. We conclude by showing that the \(C^1\) extension property implies a Lusin-like approximation theorem for horizontal curves on sub-Riemannian manifolds. 相似文献
129.
130.
Antibacterial poly(ethylene terephthalate) surfaces obtained from thymyl methacrylate polymerization
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Sophie Bedel Bénédicte Lepoittevin Ludovic Costa Olivier Leroy Diana Dragoe Jérôme Bruzaud Jean‐Marie Herry Morgan Guilbaud Marie‐Noëlle Bellon‐Fontaine Philippe Roger 《Journal of polymer science. Part A, Polymer chemistry》2015,53(17):1975-1985
Thymol, an antibacterial agent was used for the preparation of a methacrylic monomer. The conventional and atom transfer radical (ATRP) polymerizations of this monomer were studied using different conditions. Then, the functionalization of poly(ethylene terephthalate) (PET) films by “grafting from” ATRP using this monomer was investigated. In this aim, a three steps procedure was developed. The surfaces were first treated by NH3 plasma treatment to incorporate primary amino functions. Then, in a second step, ATRP initiator was grafted by reaction with bromoisobutyryl bromide. Surface initiated ATRP of thymyl methacrylate was performed in solution in the presence of a sacrificial initiator. The efficiency of these reactions was confirmed by X‐ray photoelectron spectroscopy. Wetting properties and surface energy were found to vary systematically depending to the type of functionalization and grafting. The poly(thymyl methacrylate)‐grafted PET surfaces exhibit resistance to bacterial adhesion toward Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus strains. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1975–1985 相似文献