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101.
Previous research has indicated that individual foods or beverages are ingested independently and do not produce adjustments to the intake of other constituents in the diet (de Castro, 1993; Wilson, 1991). In order to eliminate time of day as a potential contaminant, the present study investigated the accommodation of foods and beverages into the amount ingested at large evening meals only. Adults (n = 601) were paid to maintain detailed diaries of the timings, quantities and preparation techniques of everything they ingested for seven consecutive days. With the exceptions of soup, beef and chicken, 12 out of 15 types of drinks or foods were found to add to the total calories ingested in evening meals without displacing calories ingested in other forms, while ingestion of non-caloric diet sodas was not associated with differences in intake. The fat and protein, but not carbohydrate, contents of the items correlated with a measure of the satiating properties of the particular food or beverage, namely the correlation between the amount ingested of the particular type and the amounts of other nutrients ingested in the meal. The results confirm that intake at a meal is quite elastic and can be significantly influenced by the presence or absence of particular components of the meal and their constituents.  相似文献   
102.
Transgenic tobacco plants expressing the wild-type (wt) coat protein (CP) gene of alfalfa mosaic virus (AIMV) have been shown to be resistant to infection with viral particles and RNAs or to infection with viral particles only. The difference in resistance of these plants to RNA inocula was found to correlate with a difference in the expression level of the transgene. Plants expressing a mutant AIMV CP with the N-terminal serine residue changed to glycine have been shown to be susceptible to infection with wt viral particles or RNAs. By site-directed mutagenesis of AIMV cDNA a viable mutant virus encoding CP with the same N-terminal mutation was obtained. Plants expressing wt or mutant CP were resistant to the mutant virus, demonstrating that a single amino acid substitution in CP did not permit the virus to overcome CP-mediated resistance. Although the mutant CP did not confer resistance to wt virus when expressed in transgenic plants, it was still effective in classical cross-protection: plants infected with the mutant virus were resistant to severe strain of AIMV. A model to explain the data is discussed.  相似文献   
103.
Public–private partnership in urban renewal in France concerns mainly housing, transport infrastructure and large public facilities. The distinction between public, private and civil actors does not concern social and economic development. This situation tends to limit the integration of different issues and approaches in renewal projects. Also, French urban renewal projects do not produce a new type of partnership between public and private actors and the regulatory framework. These projects remain publicly dominated policy-making procedures because of the uneven distribution of resources and assets and despite a policy discourse emphasising the need for a new division of work between state, market and civil society. The current French situation cannot be understood without bearing in mind the history of urban planning policies in France. Using a historical analysis and the path-dependence approach, we highlight the resilience of inherited structures of interaction between public and private actors.  相似文献   
104.
In shedding light on the 1908–9 competition for Greater Copenhagen this article examines the contest as an instrument for the accumulation and transmission of planning know‐how, ideas and innovations in relation to the development of town planning theory and practice in the Nordic Countries. Plans are considered as both technical and cultural graphics marks reflecting alternative and possibly contradictory images of the greater city or city of the future. The discussion focuses on the relationship between urban design's twin polarities: urban transformation and creation on the one hand; concern for conservation and urban continuity on the other. After considering the competition's international dimension, the article explores the civic art strand of design in northern Europe before 1914 and the idea of the historic city by investigating the conservation movement that flourished in Copenhagen when there were rapid changes in the physical fabric. The article, based on archive materials, analyses of awarded and non‐awarded entries alike, illustrates how architects, engineers and surveyors combined their design of the city's extensions with conservation schemes for both peripheries and centre. It is suggested that, at a time when Nordic municipal authorities were pressing for comprehensive town planning, planners strove to provide ways of protecting the existing built environment. This involved not only safeguarding an emerging ‘historic city’ in contrast to the new extensions, but also proposals for maintaining urban continuity in the peripheries.  相似文献   
105.
Active starch films with glycerol and potassium sorbate were obtained by casting. Native and acetylated corn starches, as well as the mixture of them in equal proportions were used and filmogenic suspensions with pH 4.5 were also prepared. Sorbate concentration decreased during film storage due to its oxidative degradation. Active films resulted more yellow and less transparent than films without sorbate. The minimum inhibitory concentration of sorbate resulted 0.3%, regardless of the starch type and the formulation pH. The use of antimicrobial package was more effective to prevent microbial growth on food surfaces than the use of conventional methods. Additive kinetic release was neither affected by the starch type nor by the formulation pH. Sorbate diffusion process was mathematically modeled satisfactorily. Active films were able to inhibit Candida spp., Penicillium spp., S. aureus and Salmonella spp. growth. Active films extended 21% the shelf life of refrigerated cheese, regardless of the formulation pH.  相似文献   
106.
By using first-principles calculations we studied the electronic, optical and magnetic properties of ZnO co-doped with Eu and Pm. In this calculation, we used Wien2k code based on full potential linearized augmented plane waves (FP-LAPW) method with the modified Becke-Johnson (mBJ) approximation. This correction gives good band gap compared to experimental band gap. The introduction of Eu and Pm codoping leads to an increase in the band gap. Electrons can transit easily from the valence band to the conduction band, which results in an enhancement of visible light absorption in a wider absorption range. Absorption spectra reach a high value in visible and infrared light regions. With the significance of the obtained results, the studied compounds may potentially find spintronic and optoelectronic applications.  相似文献   
107.
Hydroxylated polychlorinated biphenyls also known as biphenylols, are suspected estrogen mimics found in the environment. Various derivatization schemes were evaluated and a gas chromatography-ion trap mass spectrometry method was developed for the trifluoroacetyl derivative using MS-MS techniques for the analysis of eleven biphenylols. A time-segmented chromatographic method was developed using the respective MS-MS parameters to analyze all the eleven biphenylols in a single chromatographic run. Isomers were differentiated based on the MS-MS data of the trofluoroacetyl-biphenylol derivatives. The method was applied to detect 40 pg on-column of these compounds in a spiked egg sample which simulates a real world sample.  相似文献   
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