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51.
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Daniela de Oliveira Ribeiro Bianca Waruar Lobo Nádia Maria Volpato Venício Féo da Veiga Mendes Lúcio Cabral Valeria Pereira de Sousa 《Nutrition journal》2009,8(1):51-13
Background
Preterm infants need high amounts of calcium and phosphorus for bone mineralization, which is difficult to obtain with parenteral feeding due to the low solubility of these salts. The objective of this study was to evaluate the physicochemical compatibility of high concentrations of calcium associated with organic phosphate and its influence on the stability of AIO admixtures for neonatal use. 相似文献53.
Claudia M. Asensio Valeria Nepote Nelson R. Grosso 《International Journal of Food Science & Technology》2013,48(11):2417-2428
The objective of this study was to evaluate chemical and physical stability and consumers' acceptance of olive oil flavoured with oregano essential oils (EOs; Compacto, Cordobes, Criollo and Mendocino). Samples of olive oil were added with 0.05% EO and stored in dark (D) and light (L) conditions for 126 days. Samples with oregano EO had lower lipid oxidation indicator values [K232, K269, peroxide value (PV) and anisidine value], especially in darkness. Olive oil with Cordobes EO in D had the lowest PV (18.71 meqO2 kg?1). Using prediction equations, 20 meqO2 kg?1 PV in olive oil should be reached in 34 days in L control sample and in 126 days in the Cordobes EO sample in darkness. Samples with Cordobes and Criollo EOs in darkness had the highest chlorophyll content after 126 days (2.91 and 2.88 mg kg?1, respectively). Sensory analysis showed that oregano EO addition in olive oil was detected by panellists in discriminative test and affected consumer acceptance. 相似文献
54.
Maria De Marsico Stephen Kimani Valeria Mirabella Kent L. Norman Tiziana Catarci 《Universal Access in the Information Society》2006,5(2):150-169
Most of the existing efforts for supporting the design, preparation, and deployment of accessible e-learning applications propose guidelines that primarily address technical accessibility issues. Little, if any, consideration is given to the real actors involved in the learning experience, such as didactical experts and disabled learners. Moreover, implementing artifacts addressed to the e-learning world requires a wide range of particular skills which are related not only to technical but also to didactical, pedagogical, usability, and accessibility aspects of the produced material. This paper argues that the know-how of a number of stakeholders should be blended into a joint design activity, and that it should be possible to determine the role of each participant in the successive phases of the development lifecycle of e-learning applications. The paper sketches the methodological guidelines of a design framework based on involving the users with disabilities, as well as pedagogical experts, in the development process. The novelty of this proposal mainly stems from being built up around the core of strategies and choices specifically bound to accessibility requirements. Characteristic elements of learner-centered design are then further integrated into processes and methodologies which are typical of participatory and contextual design approaches. Following such guidelines, it will be possible to gain a deeper understanding of the requirements and of the operational context of people needing accessible material, either as learners or educators. The underlying objective is to increase the potential to realize learning systems that better meet different user needs and that provide a more satisfying learning experience. Moreover, when people get involved in the development process, they gain a sense of ownership of the system and are therefore more likely to accept and “promote” it. 相似文献
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We developed a photochemical method for the online oxidation of p-hydroxymercurybenzoate (PHMB), an organic mercury species widely used for mercaptan and thiolic compound labeling. The method is based on a fully integrated online UV/microwave (MW) photochemical reactor for the digestion of PHMB, followed by cold vapor generation atomic fluorescence spectrometry (CVG-AFS) detection. The MW/UV process led to the quantitative conversion of PHMB and thiol-PHMB complexes to Hg(II), with a yield between 91% and 98%, without using chemical oxidizing reagents and avoiding the use of toxic carcinogenic compounds. This reaction was followed by the reduction of Hg(II) to Hg(0), performed in a knitted reaction coil with NaBH(4) solution, and AFS detection in an Ar/H(2) miniaturized flame. The low MW power applied (18 W) allowed us to keep constant the temperature of the photochemical reactor (21 ± 1 °C), using a flowing water bath. This avoided peak widening due to diffusion processes generally occurring at high temperatures and in the additional cooling coil. This method has been applied to the determination of thiols in human plasma, blood, and wine. 相似文献
57.
Transglutaminase effects on gelation capacity of thermally induced beef protein gels 总被引:1,自引:0,他引:1
Transglutaminase (TG) is an enzyme that catalyzes an acyl-transfer reaction between the γ-carboxyamide group of peptide or protein-bound glutaminyl residues, and primary amines. TG action on protein molecules, causes a cross-linking and polymerizing effect of these latter, through ε-(γ-glutamyl)lysine bonds. This TG-mediated protein cross-linking creates drastic physical changes in protein-rich foods. 相似文献
58.
Valeria Andriano 《Systems & Control Letters》1993,20(5)
In this paper we prove that the angular velocity equations of a symmetric rigid body can be globally stabilized by means of linear feedback when two control torques act on the body. 相似文献
59.
Two types of single-site heterogeneous catalysts have been designed so as to facilitate either the side-chain oxidation or
ring-hydroxylation of toluene in O2 (solvent-free) or by employing aqueous (H2O2) or organic (cumene hydroperoxide) hydroperoxides in high yield. The use of H2O2 and cumene hydroperoxide in particular, facilitates the ring-hydroxylation of toluene when zeolite-encapsulated metal complexes,
such as perhalogenated or tetra-nitro-substituted phthalocyanines, are used as catalysts. Nanoporous, redox molecular sieves,
display a higher tendency for the side-chain oxidation of toluene with air as an oxidant, with benzoic acid as the predominant
product. 相似文献
60.
A Manganelli G Barbanti M Fornaini MT Del Vecchio 《Canadian Metallurgical Quarterly》1996,56(1):52-54
OBJECTIVE: To estimate the magnitude of the dog bite problem in the US. METHODS: Data on dog bites were gathered as part of a 1994 national telephone survey of 5,238 randomly dialed households. Data were weighted to provide national estimates. RESULTS: The weighted total number of dog bites was 4,494,083 (estimated incidence = 18/1,000 population); of these, 756,701 persons sustained bites necessitating medical attention (incidence rate = 3/1,000). Children had 3.2 times higher medically attended bite rates than adults (6.4/1,000 children v 2/1,000 adults). CONCLUSIONS: More attention and research needs to be devoted to the prevention of dog bites. Potential prevention strategies include: educational programs on canine behavior, especially directed at children; laws for regulating dangerous or vicious dogs; enhanced animal control programs; and educational programs regarding responsible dog ownership and training. Unfortunately, the relative or absolute effectiveness of any of these strategies has not been assessed. Continuing surveillance for dog bites will be needed if we are to better understand how to reduce the incidence of dog bites and evaluate prevention efforts. 相似文献