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Douglas I. Rosendale Ian S. Maddox Michelle C. Miles Maroussia Rodier Margot Skinner Juliet Sutherland 《International Journal of Food Science & Technology》2008,43(12):2257-2267
A spectrophotometric bioassay was used to screen selected food ingredients intended for development of functional foods designed to influence the growth of gut bacteria. Dose–response profiles displaying Δgrowth, the magnitude of deviation from growth of controls, were generated for probiotics Lactobacillus reuteri, Lactobacillus rhamnosus, Bifidobacterium lactis and pathogens Escherichia coli, Salmonella Typhimurium and Staphylococcus aureus. Ingredients were manuka honey UMF?20+(dose‐dependently increased probiotics and decreased pathogens); bee pollen (biphasic growth effects against all); Rosehips and BroccoSprouts® (increased all dose‐dependently); blackcurrant oil (little effect) and propolis (inhibited all strains). Ingredients were also bioassayed in pairs to assess desirable or undesirable synergistic interactions. Observed synergies included manuka honey (predominantly desirable); rosehips or BroccoSprouts® (desirable and undesirable); blackcurrant oil (desirable) and propolis (tended towards synergies reinforcing its antimicrobial effects), collectively revealing a complex web of interactions which varied by ingredient and bacterial strain. Manuka honey was particularly effective at influencing gut bacteria. The surprising frequency of undesirable synergistic interactions illustrates the importance of pre‐testing potential ingredient combinations intended for use in functional foods. 相似文献
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Denise C. Hunter Jingli Zhang Lesley M. Stevenson Margot A. Skinner 《International Journal of Food Science & Technology》2008,43(12):2123-2129
Developing functional food products requires a structured approach for screening potential ingredients. Using the development of a product with antioxidant properties as a model, eight fruit juice concentrates were screened, including New Zealand fruits. The total phenolic content and the antioxidant capacity, using chemical‐based assays (ferric reducing antioxidant power and oxygen radical absorbance capacity assays), were determined. The potential to protect against oxidative stress in Jurkat cells was also determined. Results indicate that the total phenolic content and antioxidant capacity in chemical‐based assays were strongly correlated. However, the total phenolic content did not dictate the level of protection from oxidative stress in this cell‐based model, suggesting that the type of phenolic compounds present and interactions between them may be important, although the activity of other compounds, such as vitamin C or carotenoids, may also be implicated. This model for screening ingredients may be used to design synergistic combinations of ingredients, and results may provide supportive evidence in the development of functional foods for this and other health targets. 相似文献
14.
Incorporated ethnocultural, socioeconomic, and sex factors into one design, allowing comparisons under conditions of uncontrolled and controlled (by covariance) IQ conditions. In addition, the present study with 384 1st graders allowed for comparisons between reported Koppitz norms and error scores for the current sample. Findings suggest that if IQ (or IQ-mediated variables) were taken into account, the Koppitz system would be relatively uninfluenced by sex, ethnocultural, and socioeconomic status determinants. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Barthélemy O Margot J Laville S Vidal F Chaker M Le Drogoff B Johnston TW Sabsabi M 《Applied spectroscopy》2005,59(4):529-536
In this work, the assumption of local thermodynamic equilibrium (LTE) for a laser-induced plasma in ambient air is examined experimentally using two different laser systems, namely an infrared short-pulse Ti : Sapphire laser and an ultraviolet long-pulse XeCl excimer laser. The LTE assumption is investigated by examining the plasma produced at a laser fluence of 10 J/cm(2) from aluminum targets containing iron and magnesium impurities. The excitation temperature is deduced from Boltzmann diagrams built from a large number of spatially integrated neutral iron lines distributed from 3.21 to 6.56 eV. It is shown that at any time after the end of the laser pulse, the neutral excited states are in excellent Boltzmann equilibrium. Detailed investigation of Boltzmann equilibrium further validates previous temperature measurements using less accurate diagrams. However, observations of ion lines provide some evidence that the ionized species do not obey Saha equilibrium, thereby indicating departure from LTE. This could be explained by the fact that the plasma cannot be considered as stationary for these species. 相似文献
17.
Le Drogoff B Vidal F Laville S Chaker M Johnston T Barthélemy O Margot J Sabsabi M 《Applied optics》2005,44(2):278-281
The ablated depth and volume per laser pulse from an aluminum target were measured for pulse durations that ranged from 80 fs to 270 ps at an average fluence of approximately 100 J/cm2 and a wavelength of 0.8 microm. The ablated volume showed a flat maximum for subpicosecond pulses and a minimum for approximately 6 ps. The crater diameters were rather constant up to pulse durations of approximately 6 ps and increased for larger pulse durations. As a result, the ablated depth also showed a plateau for subpicosecond pulses but decreased monotonically with pulse duration. A physical interpretation of these results and their consequences for laser applications are discussed. 相似文献
18.
One of the more intriguing challenges faced by educators is to help their students experience “inventive learning”. This is learning in which the acquisition of factual knowledge is enhanced by creatively extending and or synthesizing that knowledge. It is similar to the personal style of learning developed by intellectually curious adults, scholars, artists, and workers in research and development environments.Two factors that can help cultivate the practive of inventive learning in students are supportive social environments and supportive physical environments. The Solo/NET/works project at the University of Pittsburgh is currently developing a microcomputer-based system that uses multiprocess simulations to create such environments.Students use personal-level microcomputers to design local processes that they then run within a larger global-process framework. It is hypothesized that learning to deal creatively with the unforseen interactions that characterize such multiprocess simulations will foster inventive learning as a natural extension of solo-mode program design. Our experience in developing a low-cost version of the Solo/NET/works system will be described, and examples of the variety of multiprocess simulations that seem possible for the system will be given. 相似文献
19.
Margot Den Hondt Jan Jeroen Vranckx 《Journal of materials science. Materials in medicine》2017,28(2):24
The trachea has a complex anatomy to fulfill its tasks. Its unique fibro-cartilaginous structure maintains an open conduit during respiration, and provides vertical elasticity for deglutition, mobility of the neck and speech. Blood vessels pierce the intercartilaginous ligaments to perfuse the ciliated epithelium, which ensures effective mucociliary clearance. Removal of a tracheal segment affected by benign or malignant disease requires airtight restoration of the continuity of the tube. When direct approximation of both tracheal ends is no longer feasible, a reconstruction is needed. This may occur in recurrent short-segment defects in a scarred environment, or in defects comprising more than half the length of the trachea. The resulting gap must be filled with vascularized tissue that restores the mucosal lining and supports the semi-rigid, semi-flexible framework of the trachea. For long-segment or circular defects, restoration of this unique biomechanical profile becomes even more important. Due to the inherent difficulty of creating such a tube, a tracheostomy or palliative stenting are often preferred over permanent reconstruction. To significantly improve and sustain quality of life of these patients, surgeons proposed innovative strategies for complex tracheal repair. In this review, we provide an overview of current clinical applications of tracheal repair using autologous and allogenic tissues. We look at recent advances in the field of tissue engineering, and the areas for improvement of these first human applications. Lastly, we highlight the focus of our research, in an effort to contribute to the development of optimized tracheal reconstructive techniques. 相似文献
20.
Fabien Cremona Alo Laas Toomas Kiv Margot Sepp Peeter Nges Tiina Nges 《Lakes & Reservoirs: Research and Management》2019,24(1):18-23
Theoretical pelagic primary production of phytoplankton and benthic primary production of periphyton were modelled for two small lakes in Estonia (Northeast Europe). Although located only 500 m apart, the water colour and light attenuation of these two lakes differed markedly. The Secchi depth (SD) in the clear‐water lake was 4.5 m and only 0.47 m in the dark‐water lake. The total phosphorus (TP) concentrations were, respectively, 15 μg/l and 28 μg/l. An empirical model whose inputs were morphometric, light conditions and dissolved organic carbon parameters obtained from in situ measurements was employed for the present study. The model calculated primary production with a time‐step of 10 min, and a spatial resolution of 10 cm, from sunrise to sunset and from lake surface to lake bottom. The primary production of periphyton and phytoplankton was almost equal in the clear lake, whereas only phytoplankton contributed to whole‐lake primary production in the dark lake because of the stronger light attenuation in the water column. The results of the present study indicated the depth‐distribution profiles differed dramatically between the two lakes. The clear lake had a deep, U‐shaped curve, with the productive layer reaching considerable depth soon after sunrise and maintaining a similar profile throughout the light hours. In contrast, the dark lake production declined rapidly with increasing depth, whereas the profile changed over the day reaching the greatest depth at noon. 相似文献