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91.
Hélène Angellier-Coussy Emmanuelle Gastaldi Nathalie Gontard Valérie Guillard 《Industrial Crops and Products》2011,33(2):457-461
The influence of processing conditions (thermoforming temperature) on water vapour transport properties (permeability, sorption and diffusion) of wheat gluten-based films was studied in relation to structural properties (cross-linking degree of the wheat gluten matrix). Increasing temperature from 80 °C to 120 °C led to a significant decrease in material swelling in high moisture environment and a WVP reduction mainly due to a decrease in diffusivity but without important effect on the moisture sorption isotherms. This was attributed to a higher cross-linking degree of protein network for film thermoformed at 120 °C, with a limited mobility and less possibilities of rearrangement in high moisture conditions. 相似文献
92.
Relationships involving several types of extractives of five native argentine wood species of genera Prosopis and Acacia 总被引:1,自引:0,他引:1
Benedetto Pizzo Carolina L. PomettiJean-Paul Charpentier Nathalie BoizotBeatriz O. Saidman 《Industrial Crops and Products》2011,34(1):851-859
The relationships existing among the values obtained when extracting the wood of four Argentinean species of Prosopis (P. alba, P. kuntzei, P. nigra, and P. ruscifolia) and one of the Acacia (A. aroma) by several procedures were evaluated and discussed. The used methods were: extraction in toluene/ethanol and hot water; determination of tannic and non-tannic content; measurement of phenolic compounds. Additionally, liquid chromatography (HPLC) was also used in order to quantitatively evaluate the content of (−)-mesquitol, a relatively unusual flavonoid (flavanol type). The total amount of Oxidation Products was also measured. They result from oxidation and polymerization processes of phenolic compounds occurring during heartwood formation, and were not separated during chromatographic analysis. Data evidenced a linear trend (R2 = 0.970) between organic and tannic extractives of all species, and a similar one (R2 = 0.927) between total phenols and tannic (or organic) extractives in the case of heartwood of Prosopis species. Interestingly, for sapwood very different values of organic extracts, tannic content or Oxidation Products type compounds were measured in spite of a similar amount of phenolic substances. Moreover, the various species presented the same peaks in chromatograms, thus evidencing the chemical similarity of compounds but a different quantity between heartwood and sapwood and also among the various species. The observed similarity implied that the various methods of extraction did not really extract only a single class of substances, and that great care must be adopted when using some specific procedures for extractions.Furthermore, the existing relationships between extractives and selected technological properties, namely specific volumetric shrinkage coefficient (BSvol) and natural durability (evaluated in terms of mass loss after fungal attacks in laboratory conditions), were given. It appeared that in heartwood BSvol was well correlated to organic extractives (R2 = 0.984), thus evidencing the microimpregnation of cell walls by extractives, but the fitting quality of the correlation was dependent on the type of extractives used. Analogously, a good relationship between mass loss and phenolic compounds existed (R2 = 0.764), and in this case the value of R2 was even more dependent on the considered extracts. Moreover, the availability of quantitative data on several Prosopis species allowed to consistently evaluate the bioactivity of (−)-mesquitol on the resistance against fungal attack, and the logarithmic form of the relationship between mass loss and (−)-mesquitol content suggested a direct fungicidal activity of this compound. On the other hand, data also evidenced that neither phenolic compounds nor (−)-mesquitol can be considered as the unique and definite factor able to determine the durability of the considered species. 相似文献
93.
Nathalie Chenais Alexandra Depince Pierre-Yves Le Bail Catherine Labbe 《Aquaculture International》2014,22(1):63-76
Domestication is a long-term process during which wild fish are acclimated to farming conditions and hopefully are reproduced over several generations, possibly using selective breeding. Preservation of the genetic diversity of the original population, together with that of the ongoing selection steps, is important for ecological and economical purposes. Cryobanking of reproductive cells is one answer to meet this need. In fish, however, only sperm can be cryopreserved as neither oocytes nor embryos are capable of handling the freeze-thawing stress. In this review, we explore to what extent diploid cells obtained from fin pieces can be used for the preservation of both parental genomes. The main parameters, which should be under control to ensure proper production of fin cells in culture and to enable cryopreservation of the material are described. After cryobanking of such non-reproductive cells, fish can be reconstructed using the nuclear transfer technology whose potentials and difficulties are discussed. The gametes produced by the fish reconstructed after somatic cells nuclear transfer are different to some extent from the gametes obtained after the direct transplantation of primordial germ cell or spermatogonial germ cells into host embryos or larvae. However, in some cases, only somatic cells can be obtained in quantities which would be compatible with strain restoration purposes. From the knowledge available today, it is reasonable to expect that nuclear transfer becomes available for fish reconstruction, even if restricted to high-tech biotechnology facilities. Therefore, cryobanking of fin somatic cells can be farsightedly considered for high-throughput diploid genome conservation. 相似文献
94.
Retrospective evaluation of 155 adult equids and 21 foals with tetanus in Western,Northern, and Central Europe (2000–2014). Part 1: Description of history and clinical evolution 下载免费PDF全文
Gaby van Galen DVM PhD DECEIM DECVECC Claude Saegerman DVM PhD DECVPH Joke Rijckaert DVM Helene Amory DVM PhD DECEIM Lara Armengou DVM PhD DECEIM Barbora Bezdekova DVM PhD DECEIM Inge Durie DVM DECEIM Rikke Findshøj Delany DVM Nathalie Fouché DVM DVM Laura Haley MVB Michael Hewetson BVSc DECEIM Rene van den Hoven DVM PhD DECEIM Anna Kendall DVM DECEIM Fernando Malalana DVM DECEIM MRCVS Jessika Muller Cavalleri DVM DECEIM PhD Tresemiek Picavet DVM DECEIM PhD Katja Roscher DVM DECEIM Denis Verwilghen DVM PhD DECVS Meret Wehrli Eser DVM DECEIM Cornélie Westermann DVM PhD DECEIM Tim Mair BVSc PhD DECEIM 《Journal of Veterinary Emergency and Critical Care》2017,27(6):684-696
95.
Anne-Noëlle Petit Nathalie Vaillant-Gaveau Anne-Sophie Walker Pierre Leroux Fabienne Baillieul Marie-Laure Panon Christophe Clément Florence Fontaine 《Crop Protection》2010
Botrytis bunch rot of grapes is mainly controlled by applying fungicides at three crop growth stages: the end of flowering (BBCH 68), bunch closure (BBCH 77) and the beginning of veraison (BBCH 81). The hydroxyanilide derivative fenhexamid is among the most effective fungicides registered to control Botrytis cinerea. Its effectiveness was examined in relation to spray timing, fungicide resistance and defense responses of grapevine. Overall, the earlier fenhexamid was applied, the more effective it was at controlling B. cinerea. Frequencies of B. cinerea strains which were resistant to fungicides were evaluated at harvest. The frequencies of resistant phenotypes were similar among treatments and years with the exception of a class of multidrug resistant strain (MDR 2) whose frequency appeared to increase after fenhexamid applications. If current spray programs including fenhexamid appear to control bunch rot at the current MDR frequency, a propagation of MDR 2 strains might lead to a decline in disease control. Finally, defense responses were studied in grapevine flowers/berries following fenhexamid application. None of the defense processes tested was induced in flowers/berries at stages 68 and 77. Only an increase in chitinase activity was observed in treated-berries at stage 81, suggesting that fenhexamid effectiveness was not related to a stimulation of defense responses. 相似文献
96.
斑茅(Erianthus arundinaceus Retz)是甘蔗的近缘属植物,具有多种优良特性,是甘蔗育种的重要种质资源之一。本实验使用基因组原位杂交(GISH)技术分析了甘蔗-斑茅杂种及回交后代F1、BC1和BC2的染色体构成与传递行为。结果表明:在F1代,来自斑茅HN92-77的染色体数目介于28~30条,来自热带种Badila的染色体数目介于38~40条,体细胞染色体数为2n=68~70,基本符合n+n的染色体传递方式;在BC1和BC2代,来自斑茅的染色体数分别为22~28条和13~15条,来自甘蔗的染色体数分别是87~94条和98~101条,其体细胞染色体数2n分别为110~121条和112~115条,基本上分别符合2n+n和n+n的染色体传递方式。在所观察的渐渗系中,均存在有染色体丢失的现象,但未观察到染色体发生交换与重组。 相似文献
97.
Modestine Raliniaina Damien F. Meyer Valérie Pinarello Christian Sheikboudou Loic Emboulé Yane Kandassamy Hassane Adakal Frédéric Stachurski Dominique Martinez Thierry Lefrançois Nathalie Vachiéry 《Veterinary parasitology》2010,167(2-4):187-195
Understanding bacterial genetic diversity is crucial to comprehend pathogenesis. Ehrlichia ruminantium (E. ruminantium), a tick-transmitted intracellular bacterial pathogen, causes heartwater disease in ruminants. This model rickettsia, whose genome has been recently sequenced, is restricted to neutrophils and reticulo-endothelial cells of its mammalian host and to the midgut and salivary glands of its vector tick. E. ruminantium harbors a multigene family encoding for 16 outer membrane proteins including MAP1, a major antigenic protein. All the 16 map paralogs are expressed in bovine endothelial cells and some are specifically translated in the tick or in the mammalian host.In this study, we carried out phylogenetic analyses of E. ruminantium using sequences of 6 MAP proteins, MAP1, MAP1-2, MAP1-6, MAP1-5, MAP1+1 and MAP1-14, localized either in the center or at the borders of the map genes cluster.We show that (i) map1 gene is a good tool to characterize the genetic diversity among Africa, Caribbean islands and Madagascar strains including new emerging isolates of E. ruminantium; (ii) the different map paralogs define different genotypes showing divergent evolution; (iii) there is no correlation between all MAP genotypes and the geographic origins of the strains; (iv) The genetic diversity revealed by MAP proteins is conserved whatever is the scale of strains sampling (village, region, continent) and thus was not related to the different timing of strains introduction, i.e. continuous introduction of strains versus punctual introduction (Africa versus Caribbean islands).These results provide therefore a significant advance towards the management of E. ruminantium diversity. The differential evolution of these paralogs suggests specific roles of these proteins in host–vector–pathogen interactions that could be crucial for developing broad-spectrum vaccines. 相似文献
98.
Benoît Quintard Thierry Petit Nathalie Ruvoen Elisabeth Carniel Christian E. Demeure 《Comparative immunology, microbiology and infectious diseases》2010,33(6):e59-e65
Pseudotuberculosis, an infection caused by the ubiquitous enteropathogenic bacterium Yersinia pseudotuberculosis, is a recurrent veterinary problem in livestock and zoo animals. The only vaccine currently available in zoos is Pseudovac (a mixture of killed strains of various serotypes), but its efficacy is not well established. We show here that Pseudovac does not protect guinea pigs against a severe Y. pseudotuberculosis infection. We thus evaluated the possibility of using a live attenuated Y. pseudotuberculosis strain (IP32680) as an oral vaccine against animal pseudotuberculosis. We report that IP32680 is avirulent for guinea pigs and induces a strong IgG response against various serotypes of Y. pseudotuberculosis. One and two oral inoculations of IP32680 provided 50% and 83% protection, respectively against a severe infection with a highly pathogenic strain. The avirulent Y. pseudotuberculosis IP32680 is therefore much more protective than Pseudovac and may represent a valuable oral vaccine against pseudotuberculosis in zoo animals. 相似文献
99.
Nathalie Wuyts Jean-Christophe Palauqui Geneviève Conejero Jean-Luc Verdeil Christine Granier Catherine Massonnet 《Plant methods》2010,6(1):17