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Nicole J. Gaudette Gary J. Pickering 《Critical reviews in food science and nutrition》2013,53(5):464-481
The functional foods sector represents a significant and growing portion of the food industry, yet formulation of these products often involves the use of ingredients that elicit less than desirable oral sensations, including bitterness. Promising new functional ingredients, including polyphenolics, may be more widely and readily employed in the creation of novel functional foods if their aversive bitter taste can be significantly reduced. A number of approaches are used by the industry to improve the taste properties and thus the acceptance of conventional foods that elicit excessive bitterness. This article reviews the most commonly employed techniques, including the use of bitter-modifying additives, which may prove useful for successfully introducing new functional ingredients into this rapidly growing sector. 相似文献
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Ivan Rehor Jitka Slegerova Jan Kucka Vladimir Proks Vladimira Petrakova Marie‐Pierre Adam François Treussart Stuart Turner Sara Bals Pavel Sacha Miroslav Ledvina Amy M. Wen Nicole F. Steinmetz Petr Cigler 《Small (Weinheim an der Bergstrasse, Germany)》2014,10(6):1106-1115
High pressure high temperature (HPHT) nanodiamonds (NDs) represent extremely promising materials for construction of fluorescent nanoprobes and nanosensors. However, some properties of bare NDs limit their direct use in these applications: they precipitate in biological solutions, only a limited set of bio‐orthogonal conjugation techniques is available and the accessible material is greatly polydisperse in shape. In this work, we encapsulate bright 30‐nm fluorescent nanodiamonds (FNDs) in 10–20‐nm thick translucent (i.e., not altering FND fluorescence) silica shells, yielding monodisperse near‐spherical particles of mean diameter 66 nm. High yield modification of the shells with PEG chains stabilizes the particles in ionic solutions, making them applicable in biological environments. We further modify the opposite ends of PEG chains with fluorescent dyes or vectoring peptide using click chemistry. High conversion of this bio‐orthogonal coupling yielded circa 2000 dye or peptide molecules on a single FND. We demonstrate the superior properties of these particles by in vitro interaction with human prostate cancer cells: while bare nanodiamonds strongly aggregate in the buffer and adsorb onto the cell membrane, the shell encapsulated NDs do not adsorb nonspecifically and they penetrate inside the cells. 相似文献
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Duffy Ryan D.; Martin Helena M.; Bryan Nicole A.; Raque-Bogdan Trisha L. 《Canadian Metallurgical Quarterly》2008,55(4):518
The purpose of the present study was to investigate methods of measuring individual research productivity for counseling psychologists. Using the 60 members of the Journal of Counseling Psychology editorial board, the authors computed a comparison of 6 popular indices of productivity, revealing considerable levels of positive skewness, kurtosis, and overlap with each other. Combining the strengths of the 6 indices, the authors developed a new productivity index entitled the Integrated Research Productivity Index (IRPI). The IRPI measures individual productivity by statistically combining an individual's author-weighted publications, average times cited by other publications, and years since first publication into a comprehensive score. Productivity values and IRPI scores for 3 groups of counseling psychologists (Tyler Award recipients, Kuder Award recipients, and Division 17 Presidents) were computed to provide evidence of discriminant validity among the indices. In contrast to the other measures examined, the IRPI accounts for productivity per year and years in the field and assesses mean citation count per article as opposed to total citation count, thus yielding similar scores for Tyler (lifetime) and Kuder (early career) research award recipients. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Vladimir Totolin Ichiro Minami Christoph Gabler Joseph Brenner Nicole Dörr 《Tribology Letters》2014,53(2):421-432
The assessment of ionic liquids (ILs) as lubricants in several tribological systems has shown their ability to provide remarkable reduced friction and protection against wear, whether they are used as additives or in the neat form. However, their corrosion and limited solubility in non-polar hydrocarbon oils represent the bottleneck-limiting factors for the use of ILs as lubricants. Therefore, in order to tackle these problems, mixtures of alkylborane–imidazole complexes with one halogen-free IL as additive were used in this study. The knowledge of the additive–surface interactions and hence the understanding of tribological properties are an important issue for lubricant formulations and were also investigated in this work. Thus, combination effects between two ionic liquid additives, a halogenated and a halogen-free one, were evaluated by a ball-on-disc-type tribometer under boundary lubrication conditions. Effective friction reduction and anti-wear properties have been demonstrated in tribological investigations when adding between 0.7 and 3.4 wt% of the halogen-free IL into base fluid composed of alkylborane–imidazole complexes. X-ray photoelectron spectroscopy analyses of the steel specimens were conducted to study the correlation between tribological properties and chemical surface composition of the boundary films formed on the rubbing surface. This work suggests potential applications for using halogen-free ILs as additives for synthetic ionic liquid lubricants. 相似文献
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Anderson Nicole D.; Craik Fergus I. M.; Naveh-Benjamin Moshe 《Canadian Metallurgical Quarterly》1998,13(3):405
Four studies examined the effects of divided attention in younger and older adults. Attention was divided at encoding or retrieval in free recall (Experiment 1), cued recall (Experiments 2 and 3), and recognition (Experiment 4). Dividing attention at encoding disrupted memory performance equally for the two age groups; by contrast, for both age groups, dividing attention at retrieval had little or no effect on memory performance. Secondary task reaction times (RTs) were slowed to a greater extent for the older adults than for the younger adults, especially at retrieval. Age-related differences in RTs costs at retrieval were largest in free recall, smaller in cued recall, and smallest in recognition. These results provide evidence for an age-related increase in the attentional demands of encoding and retrieval. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献