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51.
Marie Sarah Evers Chloé Roullier-Gall Christophe Morge Celine Sparrow Antoine Gobert Hervé Alexandre 《Comprehensive Reviews in Food Science and Food Safety》2021,20(3):2991-3035
Vitamins are essential compounds to yeasts, and notably in winemaking contexts. Vitamins are involved in numerous yeast metabolic pathways, including those of amino acids, fatty acids, and alcohols, which suggests their notable implication in fermentation courses, as well as in the development of aromatic compounds in wines. Although they are major components in the course of those microbial processes, their significance and impact have not been extensively studied in the context of winemaking and wine products, as most of the studies focusing on the subject in the past decades have relied on relatively insensitive and imprecise analytical methods. Therefore, this review provides an extensive overview of the current knowledge regarding the impacts of vitamins on grape must fermentations, wine-related yeast metabolisms, and requirements, as well as on the profile of wine sensory characteristics. We also highlight the methodologies and techniques developed over time to perform vitamin analysis in wines, and assess the importance of precisely defining the role played by vitamins in winemaking processes, to ensure finer control of the fermentation courses and product characteristics in a highly complex matrix. 相似文献
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Celine Mannion June Fanning Joanne McLernon Lynsey Lendrum Montserrat Gutierrez Sharon Duggan John Egan 《Food research international (Ottawa, Ont.)》2012,45(2):871-879
Salmonella is an important foodborne pathogen worldwide and is commonly isolated from pigs and pig products in Ireland. Pigs, reared in an environment free of Salmonella spp. or with low levels of infection, may acquire infection or become contaminated during transport, lairage or post-slaughter. The main objective of this study was to determine the role of the abattoir as a potential factor that contributes to the dissemination of Salmonella spp. in slaughter pigs from herds with a low Salmonella seroprevalence (≤ 10%). A total of 128 pigs from eight herds were monitored from farm through the slaughter process in three separate abattoirs. The prevalence of Salmonella spp. was determined in samples collected from trucks, lairage pens and the slaughterline before pigs entered, from pigs after slaughter (caecal contents and ileocaecal lymph nodes) and carcass surfaces post-evisceration. Isolates were characterised by serotype, phage type and pulsed-field gel electrophoresis (PFGE) patterns. Of the swabs taken from the trucks, lairage and slaughterline, before the pigs entered, 4.3% (3/70), 80% (64/80) and 16.7% (4/27) were positive for Salmonella spp., respectively. The proportion of pigs showing serological evidence of infection was 3.1% (4/128). Salmonella spp. were isolated from the ileocaecal lymph nodes and caecal contents of 14.8% (19/128) and 11.7% (15/128) of pigs, respectively, and 13/128 (10.2%), 5/128 (3.9%), 2/111 (1.8%) and 8/111 (7.2%) carcass swabs pre wash, post wash, post chill and belly-strip samples, respectively, were Salmonella-positive. There was only slight agreement between serological and bacteriological data at the pig level. Salmonella isolates from 45% of all positive pig samples and 82% of positive carcass samples were indistinguishable, based on PFGE patterns, from salmonellae isolated from the lairage and slaughterline. Based on these results it is concluded that the lairage and the slaughterline provide a substantial source for Salmonella contamination of pigs and carcasses. 相似文献
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We have detected the lack of a widely accepted knowledge representation model in the area of Blood Vessel analysis. We find
that such a tool is needed for the future development of the field and our own research efforts. It will allow easy reuse
of software pieces through appropriate abstractions, facilitating the development of innovative methods, procedures and applications.
We include a thorough review of vascular morphology image analysis. After the identification of the key representation elements
and operations, we propose a Vessel Knowledge Representation (VKR) model that would fill this gap. We give insights into its
implementation based on standard Object-Oriented Programming tools and paradigms. The VKR would easily integrate with existing
medical imaging and visualization software platforms, such as the Insight ToolKit (ITK) and Visualization Toolkit (VTK). 相似文献
54.
Elodie Torres Christophe Lorrette Patrick Weisbecker Cédric Sauder Celine Cabet Bruno Riccetti Laurent Briottet Francis Rebillat 《Oxidation of Metals》2013,80(3-4):267-277
Ceramic matrix composites have been identified as a potential material of core structure for the fourth generation of fission nuclear reactors. Regarding their excellent mechanical behavior in very harsh conditions (high temperature and high irradiation flux), the CVI–SiCf/SiC composites with pyrocarbon interlayer are of prime interest for the fuel cladding in the gas-cooled fast reactor. Although the working atmosphere is helium in these advanced reactors, the presence of oxidizing impurities could have a significant role on the mechanical behavior of materials subjected to long-term exposures. Within this framework, this study was intended to investigate the influence of oxidation on the SiCf/SiC composites mechanical properties. Different pre-damage states were intentionally introduced by mechanical tensile tests on plate specimens before performing an oxidation treatment of 1,000 h at 1,000 °C under helium with 10 ppm of O2. The degradation of the composite was determined from the mechanical behavior of post-exposure specimens. Results were correlated both with microstructural observations of the damage and with characterizations of the generated oxides at the surface of the composites. The most severe decline of mechanical properties occurs for the higher predamaged loadings. Indeed in this case, the silica formed during the oxidation of SiC is not in sufficient quantities to fill the cracks. 相似文献
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Julie Russias Fabien Frizon Celine Cau-Dit-Coumes Annie Malchère Thierry Douillard Christophe Joussot-Dubien 《Journal of the American Ceramic Society》2008,91(7):2337-2342
C–A–S–H (C=CaO, A=Al2 O3 , S=SiO2 , H=H2 O in cement nomenclature) phases have been synthesized from CaO, SiO2 , and AlNaO2 . The initial CaO/SiO2 (C/Sinitial ) ratios varied from 0.8 to 1.5 and the initial Al2 O3 /SiO2 (A/Sinitial ) ratio was set to 0.1. Samples were characterized by X-ray diffraction and chemical analyses of their equilibrium solutions. This paper describes experiments using a low-voltage scanning transmission electron microscopy (STEM-in-SEM) imaging system that allows transmission observations in an environmental scanning electron microscope. Observations of the nanostructure were also performed by transmission electron microscopy (TEM). Two types of morphologies were clearly observed: fine fibrillar aggregates and small plates, the latter being particularly sensitive to beam damage. Despite their different appearance, both of these phases were amorphous, and the small plates were richer in aluminum. The fraction of the small plate phase increased with the C/Sinitial ratio. TEM interpretations showed that C–A–S–H phases were not stable under the electron beam and high-magnification observations could significantly modify their structure. Images and chemical analyses acquired with STEM-in-SEM appeared as valuable sources of information because they offered a large observation field comparable to a transmission electron microscope and better magnification resolution than a classical scanning electron microscope. 相似文献
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Lai Wah Chan Ai Ling Ching Celine Valeria Liew Paul Wan Sia Heng 《Drug development and industrial pharmacy》2013,39(6):667-676
ABSTRACTThe influence of sodium alginate viscosity on the dynamics of matrix hydration, solvent front movement, swelling, erosion, and drug release from alginate matrix tablets were examined. The solvent front showed preferential penetration from the radial direction even though matrix swelling showed axial predominance. This study proposed alternative views for the anisotropic behavior of hydrating alginate compacts, namely, formation of gel barrier with different permeability characteristics, tension at the gel-core interface and preferential radial erosion, in addition to an in-depth examination on the contribution of stress relaxation of hydrated polymer as well as core expansion. Alginate matrices demonstrated pH-dependent hydration, swelling and erosion behavior, resulting in pH-dependent drug release mechanisms. Dissolution profiles for alginate matrices of different viscosities were similar in acid but differed upon increase of pH. This was due to the influence of alginate viscosity grade on liquid uptake, erosion and pronounced swelling at near neutral pH. 相似文献
60.
Celine Boileau Sofia Pessanha Chantal Tardif Kepa Castro Noemi Proietti Donatella Capitani Silvia Vicini Juan Manuel Madariaga Maria Luisa Carvalho Elisabetta Princi 《应用聚合物科学杂志》2009,113(3):2030-2040
The chemical and biological deterioration of paper‐based materials is mainly due to the degradation of its main component, the cellulose. However, paper also contains small amounts of organic and inorganic additives which might influence its biodegradability. To protect the paper‐based materials against various degradative agents, coating treatments with polymeric materials might be developed. In this study, the protective effect of commercial waterborne polyurethanes (WPU) against an enzymatic attack was investigated. Uncoated and coated samples with WPU of newsprint were subjected to degradation by enzymatic complexes (cellulosomes) produced by Clostridium cellulolyticum for different incubation times and then characterized using several analytical techniques (energy dispersive X‐ray fluorescence, scanning electron microscopy, nuclear magnetic resonance, Raman and infrared spectroscopy) with the aim to assess if waterborne polyurethanes can be used in paper conservation, looking at their efficacy against the biodegradation induced by enzymes. The selected waterborne polyurethanes showed a high effectiveness in the protection of paper‐based materials when they were submitted to the enzymatic attack. Indeed, their presence delayed the destruction of the cellulose matrix and the release of both soluble sugars and paper additives. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献