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Changes of the cell surface hydrophobicity of Lactobacillus acidophilus La‐5 in response to pH,temperature and inulin 下载免费PDF全文
Antonio Bevilacqua Leonardo Petruzzi Barbara Speranza Daniela Campaniello Milena Sinigaglia Maria Rosaria Corbo 《International Journal of Food Science & Technology》2018,53(5):1262-1268
The main topic of this study was to study how cell surface hydrophobicity (CSH) could change in response to pH, temperature and inulin; Lactobacillus acidophilus La‐5 was used as a model microorganism. pH, temperature, inulin and incubation time (exposure to prebiotic or incubation at pH 4.0 and 9.0) were combined through a full factorial design and a Central Composite Design; the results were analysed using a multifactorial anova (first step) and a stepwise regression (second step). Temperature and pH significantly affected CSH: an increase in the temperature determined a significant increase in CSH, whereas the correlation pH vs. CSH was negative, as an increase in pH caused a significant decrease in CSH. Inulin played a significant role, but its effect could be influenced by temperature, pH and exposure time. This study is the first approach on the effects of some environmental factors on CSH and suggests that the culturing conditions and/or the exposure to some prebiotics could modify it with positive or negative effects. 相似文献
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Barbara Walther Aaron M. Lett Alessandra Bordoni Lidia Toms‐Cobos Juan Antonio Nieto Didier Dupont Francesca Danesi Danit R. Shahar Ana Echaniz Roberta Re Aida Sainz Fernandez Amlie Deglaire Doreen Gille Alexandra Schmid Guy Vergres 《Molecular nutrition & food research》2019,63(21)
Nutritional research is currently entering the field of personalized nutrition, to a large extent driven by major technological breakthroughs in analytical sciences and biocomputing. An efficient launching of the personalized approach depends on the ability of researchers to comprehensively monitor and characterize interindividual variability in the activity of the human gastrointestinal tract. This information is currently not available in such a form. This review therefore aims at identifying and discussing published data, providing evidence on interindividual variability in the processing of the major nutrients, i.e., protein, fat, carbohydrates, vitamins, and minerals, along the gastrointestinal tract, including oral processing, intestinal digestion, and absorption. Although interindividual variability is not a primary endpoint of most studies identified, a significant number of publications provides a wealth of information on this topic for each category of nutrients. This knowledge remains fragmented, however, and understanding the clinical relevance of most of the interindividual responses to food ingestion described in this review remains unclear. In that regard, this review has identified a gap and sets the base for future research addressing the issue of the interindividual variability in the response of the human organism to the ingestion of foods. 相似文献
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Elisa Franzoni Barbara Pigino Gabriela Graziani Claudio Lucchese Alberto Fregni 《Materials and Structures》2016,49(4):1527-1542
Given the high energy consumption connected to old buildings and their large environmental impact, there is a strong need for effective solutions for the building envelope retrofitting. Among these solutions, external thermal insulation composite systems (ETICS) have found large application in recent decades. In this paper a new kind of large-size thermal insulation composite boards, prefabricated using porcelain stoneware slab finishing, was developed. Different thermal insulating materials and adhesives, with and without glass fibre mesh, were tested by both current methodologies and purposely designed tests, in order to assess their physical–mechanical properties and durability performance, finally selecting the most suitable materials for the composite board. The strong points of this composite board are mainly: (i) its short placing time and improved execution quality, due to prefabrication; (ii) its high aesthetical value; (iii) its high durability, as the finishing layer is mostly insensible to weathering. The results highlight the good performances of the prefabricated composite board developed in this study (generally higher than current ETICS). The testing procedure followed in this study is also meant to give a contribution to the establishment of methodologies for the selection and durability assessment of materials for the building envelope retrofitting. 相似文献
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Giuseppe Ateniese Alfredo De Santis Anna Lisa Ferrara Barbara Masucci 《Journal of Cryptology》2012,25(2):243-270
A time-bound hierarchical key assignment scheme is a method to assign time-dependent encryption keys to a set of classes in a partially ordered hierarchy, in such a way
that each class can compute the keys of all classes lower down in the hierarchy, according to temporal constraints. 相似文献
108.
Ngoyi K. Z. Bukonda Barbara Smith Tumba G. Disashi JaneRose Njue Kyoung Hag Lee 《Journal of population ageing》2012,5(1):47-66
Socio-demographic and medical information about internally displaced persons in all parts of the world is lacking. One area where many of these persons reside is the Democratic Republic of Congo. A cross-sectional survey was used to assess the differences, if any, between elderly and non-elderly internally displaced parents in Cibombo Cimuangi, a resettlement community in the Eastern Kasai province. The survey was undertaken in 2005. Adults members from these households provided data on the experience of disease episodes over a six-month period and demographic information. Elderly internally displaced parents (older than 60 years) and non-elderly displaced parents were compared in number of illnesses (e.g., fever, weight loss) and selected demographic variables. These groups are similar in terms of experience of disease, but significantly different in terms of level of spouse's education and concentration of adult children in the household. Adjusting for these two demographic variables did not change the experience of illness for either type of parents. We discussed reasons for the absence of differences in disease incidence between the two groups and several factors that will impact internally displaced persons in Africa in the future. 相似文献
109.
Buzzi Maria Claudia Buzzi Marina Leporini Barbara Trujillo Amaury 《Multimedia Tools and Applications》2017,76(4):5141-5169
Multimedia Tools and Applications - We present an analysis of how visually impaired people perform gestures on touch-screen smartphones and report their preferences, explaining the procedure and... 相似文献
110.
Dr. Barbara Tränkenschuh 《真空研究与实践》2013,25(1):6-12
Cleaning before coating — the last step of the manufacturing process Before coating the surface of the component which shall be coated is cleaned. Several machines and chemicals can be used. After the cleaning the surface must be ready for coating. The influence of the machining parameters on the surface of a component is shown. The effectiveness of the cleaning processes prior to coating is discussed, and put in context to the whole manufacturing process. A classification of the manufacturing process should not be based on the different locations where it takes place. All the machining steps which influence the properties and the coat ability of the metal surface should be considered as connected. All these treatment steps are ideally tuned in a way that the surface can be coated flawlessly. 相似文献