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121.
Anna M. Maj Isabelle Suisse Catherine Méliet Francine Agbossou-Niedercorn 《Tetrahedron: Asymmetry》2010,21(16):2010-2014
The enantioselective hydrogenation of indole esters has been carried out efficiently in the presence of a rhodium catalyst modified by Walphos-type chiral ligands. The addition of a base can be beneficial in some catalytic conditions. 相似文献
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Quantum cascade devices processed into double metal cavities with subwavelength thickness and a grating on top are studied at terahertz frequencies. The power extracted from the devices as a function of the device thickness and the grating period is analyzed owing to electrodynamical modeling of dipole emission based on a modal method in multilayer systems. The experimental data thus reveal a strong Purcell enhancement, with Purcell factors up to approximately 50. 相似文献
125.
OBJECTIVES: Marfan syndrome (MFS) is a relatively frequent systemic connective tissue disorder with an important physical morbidity and mortality. The influences of MFS on physical problems, perception of severity, and impact on the quality of life and psychosocial well-being have been studied only limitedly. The aim of this study was to assess the association between the severity derived from the reported symptoms and subjectively experienced severity of MFS (expressed as a global judgment), with special emphasis regarding impact on relationships and pregnancies, psychosocial adjustment, and differences between the seven European countries. METHODS: A questionnaire designed specifically for this study and translated in each of the native languages was sent to 2,080 members of one of the patient support groups in Belgium, Denmark, France, Germany, The Netherlands, Switzerland, and the United Kingdom. 857 MFS patients of 13 years and older completed the questionnaire and were included in the data analysis. RESULTS: Physical impairments were scored by perception of severity of physical symptoms by the patients (physical severity perception score) and by their perception of the influence of MFS on their life (subjective severity score). Main discrepancy between physical severity perception and subjective severity score was the higher percentage of patients scoring in physical severity perception as severe (53.5%) compared to subjectively severe (26.5%). 61% of those who scored on the physical severity score as severely affected were designated as being mildly-moderately affected on subjective scoring. Both severity scores increased significantly with age. Two hundred-twenty women have carried 430 pregnancies (1.95 pregnancies/woman), with cardiovascular complications in 1.6%. Prenatal studies for MFS were rejected by 7.6% of MFS patients of 25 years and older, 33.6% were undecided, and 48.5% favored prenatal diagnosis for MFS if available. A positive general self-image was reported by 91.5% of patients. However, more than 90% stated that MFS had a negative influence on their sexual relationships, which they ascribed to negative perception of their body image. CONCLUSIONS: MFS has significant impact on daily life activities, but the majority of patients come to terms with their condition. Acceptance is mainly determined by subjective severity, and less by physical symptoms as reported by the patients themselves. It is important to stimulate a positive attitude towards MFS. 相似文献
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MgI2‐Mediated Chemoselective Cleavage of Protecting Groups: An Alternative to Conventional Deprotection Methodologies 下载免费PDF全文
Mathéo Berthet Florian Davanier Dr. Gilles Dujardin Prof. Jean Martinez Dr. Isabelle Parrot 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(31):11014-11016
The scope of MgI2 as a valuable tool for quantitative and mild chemoselective cleavage of protecting groups is described here. This novel synthetic approach expands the use of protecting groups, widens the concept of orthogonality in synthetic processes, and offers a facile opportunity to release compounds from solid supports. 相似文献
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Barwick Vicki Ellison Stephen L. R. Gjengedal Elin Magnusson Bertil Molinier Olivier Patriarca Marina Sibbesen Lorens Vanlaethem Nicole Vercruysse Isabelle 《Accreditation and quality assurance》2017,22(5):253-263
Accreditation and Quality Assurance - Eurachem held a workshop on method validation in analytical sciences in Gent, Belgium, on 9–10 May 2016. A summary of the working group discussions is... 相似文献
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Ludivine Ferey Nathalie Delaunay Douglas N. Rutledge Alain Huertas Yann Raoul Pierre Gareil Jérôme Vial Isabelle Rivals 《Analytica chimica acta》2014
Because of their high toxicity, international regulatory institutions recommend monitoring specific polycyclic aromatic hydrocarbons (PAHs) in environmental and food samples. A fast, selective and sensitive method is therefore required for their quantitation in such complex samples. This article deals with the optimization, based on an experimental design strategy, of a cyclodextrin (CD) modified capillary zone electrophoresis separation method for the simultaneous separation of 19 PAHs listed as priority pollutants. First, using a central composite design, the normalized peak-start and peak-end times were modelled as functions of the factors that most affect PAH electrophoretic behavior: the concentrations of the anionic sulfobutylether-β-CD and neutral methyl-β-CD, and the percentage of MeOH in the background electrolyte. Then, to circumvent computational difficulties resulting from the changes in migration order likely to occur while varying experimental conditions, an original approach based on the systematic evaluation of the time intervals between all the possible pairs of peaks was used. Finally, a desirability analysis based on the smallest time interval between two consecutive peaks and on the overall analysis time, allowed us to achieve, for the first time in CE, full resolution of all 19 PAHs in less than 18 min. Using this optimized capillary electrophoresis method, a vegetable oil was successfully analyzed, proving its suitability for real complex sample analysis. 相似文献
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Morphine-6-glucuronide (M6G) is the primarily active metabolite of morphine, produced endogenously by the UGT enzyme, which displays analgesic activity. For this reason, M6G is a promising drug candidate for the treatment of severe pain. We described herein a new, efficient and scalable synthesis of M6G using dimorphinic derivatives. This preparation of M6G could be performed on multigram scale with good yield and high purity. 相似文献