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排序方式: 共有832条查询结果,搜索用时 31 毫秒
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Piero Portincasa Leonilde Bonfrate Mirco Vacca Maria De Angelis Ilaria Farella Elisa Lanza Mohamad Khalil David Q.-H. Wang Markus Sperandio Agostino Di Ciaula 《International journal of molecular sciences》2022,23(3)
Gut microbiota encompasses a wide variety of commensal microorganisms consisting of trillions of bacteria, fungi, and viruses. This microbial population coexists in symbiosis with the host, and related metabolites have profound effects on human health. In this respect, gut microbiota plays a pivotal role in the regulation of metabolic, endocrine, and immune functions. Bacterial metabolites include the short chain fatty acids (SCFAs) acetate (C2), propionate (C3), and butyrate (C4), which are the most abundant SCFAs in the human body and the most abundant anions in the colon. SCFAs are made from fermentation of dietary fiber and resistant starch in the gut. They modulate several metabolic pathways and are involved in obesity, insulin resistance, and type 2 diabetes. Thus, diet might influence gut microbiota composition and activity, SCFAs production, and metabolic effects. In this narrative review, we discuss the relevant research focusing on the relationship between gut microbiota, SCFAs, and glucose metabolism. 相似文献
53.
Biosurfactants from Urban Wastes for Detergent Formulation: Surface Activity and Washing Performance
Piero Savarino Enzo Montoneri Giorgia Musso Vittorio Boffa 《Journal of surfactants and detergents》2010,13(1):59-68
To promote biobased products for industry, six biosurfactants (BS) isolated from green and food urban residues aged under
aerobic digestion for 0–60 days were investigated for their chemical composition, surface activity properties and detergent
performance in fabric washing in comparison with commercial anionic and nonionic surfactants (CS). The BS exhibited a range
of chemical composition and surface activity properties presumably related to their different biomass sources. Surface tension
data for these substances correlated meaningfully with performance data in fabric washing. It was found that BS have similar
performances as CS when used neat, but the 1:1 w/w BS–CS mixes are characterized by significant synergy. High sensitivity
to water hardness and fabric yellowing were found to be the main deficiencies for the BS. However, both effects are minimized
or are not critically evident when the BS are used together with CS and/or in common detergents formulations. The results
indicate that when used above critical micellar concentration, no significant or critical performance differences are evident
within the whole group of BS or between BS and CS. These facts encourage expectations for industrial production and real commercialization
of BS as components of detergents formulations. 相似文献
54.
This paper extends a method previously introduced by the authors for building a transparent fault classification algorithm by combining the fuzzy clustering, fuzzy logic and decision trees techniques. The baseline method transforms an opaque, fuzzy clustering-based classification model into a fuzzy logic inference model based on linguistic rules which can be represented by a decision tree formalism. The classification model thereby obtained is transparent in that it allows direct interpretation and inspection of the model. An extension in the procedure for the development of the fuzzy logic inference model is introduced to allow the treatment of more complicated cases, e.g. splitted and overlapping clusters. The corresponding computational tool developed relies on a number of parameters which can be tuned by the user to optimally compromise the level of transparency of the classification process and its efficiency. A numerical application is presented with regards to the fault classification in the Steam Generator of a Pressurized Water Reactor. 相似文献
55.
Piero Lissoni 《室内设计与装修》2018,(7)
正作为太古酒店屡获殊荣的居舍系列(The House Collective)全球第四间酒店,上海镛舍坐落于繁华的静安区,同时毗邻潮流街区南京西路。上海镛舍延续居舍系列一贯的品牌理念,致力于为宾客打造申城繁华中心的雅致居舍。室内设计由意大利著名设计师Piero Lissoni操刀主理,他从上海悠久深厚的工艺文化中汲取灵感,将标志性的简约风格与经典的上海元素完美融合。清晰现代的线条、精心挑选的材料和微妙大胆的色彩,搭配以海派文化、艺 相似文献
56.
Antonino Rizzuti Rocco Caliandro Vito Gallo Piero Mastrorilli Giuseppe Chita Mario Latronico 《Food chemistry》2013
X-ray powder diffraction was combined, for the first time, with Nuclear Magnetic Resonance spectroscopy and direct infusion mass spectrometry to characterise fresh and brined grape leaves. Covariance analysis of data generated by the three techniques was performed with the aim to correlate information deriving from the solid part with those obtained for soluble metabolites. The results obtained indicate that crystalline components can be correlated to the metabolites contained in the grape leaves, paving the way to the use of X-ray diffraction analysis for food fingerprinting purposes. Moreover it was ascertained that, differently from most of the metabolites present in the fresh vine leaves, linolenic acid (an omega-3-fatty acid) and quercetin-3-O-glucuronide (a polyphenol metabolite) do not undergo sensible degradation during the brining process, which is used as preservative method for the grape leaves. 相似文献
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The quality of the image produced by an outdoor optical system is affected by the presence of atmospheric aerosols between object and receiver. The properties of the point-spread function that result from aerosol particles were calculated by a new Monte Carlo code called MEDIA (an acronym for Modélisation des Effets de Diffusion Inhérents à l'Atmosphère). The influence of the scattering phase function's angular dependence on the irradiance of the focal plane of a detector was studied. Calculations were performed by use of Mie theory and of the Henyey-Greenstein formulation for the same asymmetry parameter and various detector optical characteristics and atmospheric conditions. Major variations were observed for strong forward-peaked scattering phase functions and a large detector field of view. 相似文献
60.
Paolo Casoli Andrea Vacca Germano Franzoni Gian Luigi Berta 《Simulation Modelling Practice and Theory》2006,14(8):1059
This paper presents a numerical model for the simulation of a swash-plate axial piston pump, focusing on the characterization of fluid properties.As it is well known, the reduction of flow oscillations (which generates pressure ripples and produces vibration and noise in the entire circuit) and the avoidance of cavitation are the major problems in the design of these pumps. Developing a simulation code can be very useful for component optimisation in order to predict and reduce the undesired phenomena. The paper first gives a quick overview on a previously developed pump model; afterwards four different models of the fluid are presented: they take into account cavitation in different ways. Their aim at characterizing as well as possible the unsteady and erratic cavitation features in a simplified manner, in order to apply the models to the simulation of hydraulic components.In the second part of the paper an application is shown of these models to an axial piston pump: a few results are presented and compared with available test data. The effects of the fluid models on the predicted pump performance are shown and commented. 相似文献