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161.
162.
Julien Chevallier Author Vitae 《Energy Economics》2011,33(1):99-110
This article investigates the presence of outliers in the volatility of carbon prices. We compute three different measures of volatility for European Union Allowances, based on daily data (EGARCH model), option prices (implied volatility), and intraday data (realized volatility). Based on the methodology developed by Zeileis et al. (2003) and Zeileis (2006), we detect instability in the volatility of carbon prices based on two kinds of tests: retrospective tests (OLS-/Recursive-based CUSUM processes, F-statistics, and residual sum of squares), and forward-looking tests (by monitoring structural changes recursively or with moving estimates). We show evidence of strong shifts mainly for the EGARCH and IV models during the time period. Overall, we suggest that yearly compliance events, and growing uncertainties in post-Kyoto international agreements, may explain the instability in the volatility of carbon prices. 相似文献
163.
The sodium iodide symporter (NIS) is responsible for the accumulation of iodide in the thyroid gland. This transport process is involved in numerous thyroid dysfunctions and is the basis for human contamination in the case of exposure to radioactive iodine species. 4‐Aryl‐3,4‐dihydropyrimidin‐2(1H)‐ones were recently discovered by high‐throughput screening as the first NIS inhibitors. Described herein are the synthesis and evaluation of 115 derivatives with structural modifications at five key positions on the pyrimidone core. This study provides extensive structure–activity relationships for this new class of inhibitors that will serve as a basis for further development of compounds with in vivo efficacy and adequate pharmacokinetic properties. In addition, the SAR investigation provided a more potent compound, which exhibits an IC50 value of 3.2 nM in a rat thyroid cell line (FRTL5). 相似文献
164.
T Bizollon S Guichard SN Ahmed P Chevallier C Ducerf M Sepetjan J Baulieux C Trepo 《Canadian Metallurgical Quarterly》1998,29(6):893-900
Large-scale DNA sequencing is creating a sequence infrastructure of great benefit to protein biochemistry. Concurrent with the application of large-scale DNA sequencing to whole genome analysis, mass spectrometry has attained the capability to rapidly, and with remarkable sensitivity, determine weights and amino acid sequences of peptides. Computer algorithms have been developed to use the two different types of data generated by mass spectrometers to search sequence databases. When a protein is digested with a site-specific protease, the molecular weights of the resulting collection of peptides, the mass map or fingerprint, can be determined using mass spectrometry. The molecular weights of the set of peptides derived from the digestion of a protein can then be used to identify the protein. Several different approaches have been developed. Protein identification using peptide mass mapping is an effective technique when studying organisms with completed genomes. A second method is based on the use of data created by tandem mass spectrometers. Tandem mass spectra contain highly specific information in the fragmentation pattern as well as sequence information. This information has been used to search databases of translated protein sequences as well as nucleotide databases such as expressed sequence tag (EST) sequences. The ability to search nucleotide databases is an advantage when analyzing data obtained from organisms whose genomes are not yet completed, but a large amount of expressed gene sequence is available (e.g., human and mouse). Furthermore, a strength of using tandem mass spectra to search databases is the ability to identify proteins present in fairly complex mixtures. 相似文献
165.
L Ginot N Ait-Bouali M Besse P Chevallier F Goldberg J Buisson 《Canadian Metallurgical Quarterly》1997,9(4):379-396
We know better the violences made by the youngs than those they suffer from. The purpose of this study is to assess, as for a city surrounding Paris, the prevalence of the violences they felt and its relation with the psychic uneasiness. Some 344 youngs (from 15 to 25 years old) selected in the city, have filled in an autoquestionnaire. It has shown that 61.6% of them have already suffered from violences, among them 44.5% from adults and what is more from institutional adults. 13.7% of the selected youngs were victims of regular violences in school sphere and 12.8% in urban environment. The expression of a psychic uneasiness is linked to the previous violences they have felt. The feeling of call for help by a psychologist or a psychiatrist is in relation with the past psychic discomfort and not with the past suffered violences. 相似文献
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168.
Loukina T. Chevallier R. de Bourgrenet de la Tocnaye J.L. Barge M. 《Lightwave Technology, Journal of》2003,21(9):2067-2073
We describe the principle of a dynamic spectral equalizer (DSE), combining high dispersive capabilities of free-space wavelength-demultiplexing optics with a polarization independent polymer-dispersed liquid-crystal spatial light modulator (SLM), to provide wide-spectral-range quasi-continuous variable-gain attenuation and flattening. Preliminary results on C band are presented and discussed, as well as possible extensions toward C + L bands and metropolitan network functionalities. 相似文献
169.
The LYP1 gene of Saccharomyces cerevisiae was cloned by complementation in lysine-permease-deficint recipient yeast cells, and its nucleotide sequence was determined. An open reading frame of 1833 nucleotides was found encoding a polypeptide of 611 amino acids, with a calculated molecular weight of 68 118. Analysis of the deduced primary structure of the protein revealed ten membrane-spanning regions and three potential N-glycosylation sites. Analysis of the deduced sequence of protein LYP1 indicates homology with other yeast amino-acid permeases, in particular with CAN1, and also the lysine-specific permease of Escherichia coli. The strain transformed by a multi-copy plasmid harbouring the LYP1 gene, showed a 20-fold increase in the maximum velocity of lysine uptake over that in the wild type, with no changes in the affinity of the permease for its substrate. 相似文献
170.