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排序方式: 共有255条查询结果,搜索用时 31 毫秒
81.
van der Sluis AA Dekker M Skrede G Jongen WM 《Journal of agricultural and food chemistry》2004,52(10):2840-2848
There is a great interest in food components that possess possible health-protecting properties, as is the case with flavonoids. Previous research showed that conventional apple juice processing resulted in juices poor in flavonoids and with a low antioxidant activity. This paper shows that it is possible to improve flavonoid content in juice and its antioxidant activity by applying an alcoholic extraction either on the pulp or on the pomace. The levels of flavonoids and chlorogenic acid in enriched juice were between 1.4 (chlorogenic acid) and 9 (quercetin glycosides) times higher than in conventional apple juice. In enriched juice the antioxidant activity was 5 times higher than in conventional apple juice, with 52% of the antioxidant activity of the originating fruits present. The novel processing method had similar effects for three apple cultivars tested (Elstar, Golden Delicious, and Jonagold). The taste and color of enriched juice were different from those of conventional juice. 相似文献
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83.
An Integrative Approach to Value‐Added Planning: From Community Needs to Local Authority Revenue
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The concept of value‐added planning (as part of the Valuing Attractive Landscapes in the Urban Economy, INTERREG IVB North West Europe Project) is introduced in this paper to facilitate integrative planning, focusing on the benefits that use and non‐use green spaces can provide to an urban area. The aim is to stress the need to plan for, and protect, green spaces in urban areas by determining the economic values connected to the green spaces and relate that values to community benefit and local authority revenue. The paper identifies tools that can be used to determine the economic value of green spaces based on the environmental, social, and economic benefits. The first section (value) refers to the social value of green spaces as determined from the public perspective and introduces the workbench method as a tool to assist with participatory planning and capturing of the social benefits of green spaces. The second section (added) refers to the environmental benefits of green spaces and, by means of the Green Credit Tool, introduces ways to ensure the protection of the green resources in an area. The final section (planning) refers to the economic benefit of green space, bringing use values and non‐use values of green spaces together. The paper concludes with an integrative framework for value‐added planning, incorporating all the tools presented in the paper, capturing the social, environmental, and economic benefits of green spaces and relating it to community benefit and local authority revenue. 相似文献
84.
Consumer acceptance of cultured meat is expected to depend on a wide diversity of determinants ranging from technology-related perceptions to product-speciifc expectations, and including wider contextu... 相似文献
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87.
Steukers L Vandekerckhove AP Van den Broeck W Glorieux S Nauwynck HJ 《Veterinary research》2011,42(1):33
ABSTRACT: In general, members of the Alphaherpesvirinae use the epithelium of the upper respiratory and/or genital tract as a preferential site for primary replication. Bovine herpesvirus type 1 (BoHV-1) may replicate at both sites and cause two major clinical entities designated as infectious bovine rhinotracheitis (IBR) and infectious pustular vulvovaginitis/balanoposthitis (IPV/IPB) in cattle. It has been hypothesized that subtype 1.1 invades preferentially the upper respiratory mucosa whereas subtype 1.2 favors replication at the peripheral genital tract. However, some studies are in contrast with this hypothesis. A thorough study of primary replication at both mucosae could elucidate whether or not different BoHV-1 subtypes show differences in mucosa tropism. We established bovine respiratory and genital organ cultures with emphasis on maintenance of tissue morphology and viability during in vitro culture. In a next step, bovine respiratory and genital mucosa explants of the same animals were inoculated with several BoHV-1 subtypes. A quantitative analysis of viral invasion in the mucosa was performed at 0 h, 24 h, 48 h and 72 h post inoculation (pi) by measuring plaque latitude and penetration depth underneath the basement membrane. All BoHV-1 subtypes exhibited a more profound invasion capacity in respiratory tissue compared to that in genital tissue at 24 h pi. However, at 24 h pi plaque latitude was found to be larger in genital tissue compared to respiratory tissue and this for all subtypes. These similar findings among the different subtypes take the edge off the belief of the existence of specific mucosa tropisms of different BoHV-1 subtypes. 相似文献
88.
Paul Vanhaecke Lieven De Vrieze Wim Tackaert Patrick Sorgeloos 《Journal of the World Aquaculture Society》1990,21(4):257-262
Decapsulated Arremia cysts have been evaluated as a direct food source for larvae of the carp Cyprinus carpio L. All decapsulated cyst diets gave excellent survival of carp larvae during the first two weeks of culturing. Unlike traditionally brine-stored decapsulated cysts, dried Artemia embryos provided growth results comparable to those obtained with freshly hatched Artemia nauplii. Furthermore, except for Artemia embryos that lost their hatchability after long-term storage in air, several other inactivation treatments, simulating improper harvesting and processing of cysts, did not produce a significant decrease in the nutritional quality of the decapsulated cysts.
Using decapsulated cysts 89 a direct food source for carp larvae, instead of nauplii, the quantity of cysts needed can be reduced by about 25% to 35% after one and two weeks of culturing, respectively. Moreover, the use of decapsulated cysts advances the possible commercialition of poor-hatching and less expensive cyst products for culture of carp larvae. 相似文献
Using decapsulated cysts 89 a direct food source for carp larvae, instead of nauplii, the quantity of cysts needed can be reduced by about 25% to 35% after one and two weeks of culturing, respectively. Moreover, the use of decapsulated cysts advances the possible commercialition of poor-hatching and less expensive cyst products for culture of carp larvae. 相似文献
89.
Peter K. Jensen Yutaka Matsuno Wim van der Hoek Sandy Cairncross 《Irrigation and Drainage Systems》2001,15(2):117-128
The standards for irrigation water qualityare currently provided by global andnational guidelines that are mostly basedon the assumption that threshold valuescould be applied to protect crops. Thisapproach can create problems for a largelyunrecognized group of people who make useof irrigation water for non-agriculturalpurposes. At the same time, increasingwater scarcity will lead to the need forrecycling of water in irrigated riverbasins, and the use of low qualityirrigation water. Apart from hazards ofhigh pollutant levels, a sustainabilitycriterion has to be included in the waterquality guidelines to account for long-termlow-level application of certain pollutantsthat can accumulate in the environment.Using the example of cadmium, it is arguedthat the current guidelines need to berevised and should take local factors andfuture developments into account. 相似文献
90.
F. Stevens P. Bogaert K. Van Oost S. Doetterl B. Van Wesemael 《European Journal of Soil Science》2014,65(4):539-552
The heterogeneity of the spatial distribution of soil organic carbon (SOC) at the landscape scale is generally not considered in regional or national SOC dynamics models. In cropland this heterogeneity is controlled largely by topography, which influences the distribution of water, energy and sediments, and thus the SOC dynamics. Sediment redistribution rates have increased strongly since the mechanization of agriculture. The over‐simplification of landscape processes in regional models of C dynamics may add to the uncertainty in C balances. Therefore, a better characterization of the importance of landscape‐scale effects on the SOC distribution throughout a region is needed. This study characterized the relative importance of geomorphology in the SOC horizontal and vertical variability across croplands in the Belgian loess belt region. A large legacy dataset of soil horizons was exploited together with 147 recently sampled profiles. Mean SOC depth profiles for different soil types were compared. Various topographic attributes were computed from a digital elevation model, and their influence on SOC was quantified through simple linear models. Finally, SOC content was mapped at three depth layers through multiple linear models, and results were cross‐validated. The legacy dataset allowed identification of significant differences in the mean SOC profile according to texture, drainage or profile development classes. A clear relationship between SOC content and topographic attributes was demonstrated, but only for the recently sampled profiles. This may be explained by a substantial error in the location of the profiles of the legacy dataset. This study thus shows evidence that the major control of the vertical distribution of SOC is related to topography in a region where observed heterogeneities for other commonly involved factors are limited. However, the large amount of unexplained variability still limits the usefulness of the spatial prediction of SOC content, and suggests the importance of additional influencing factors. 相似文献