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排序方式： 共有2061条查询结果，搜索用时 15 毫秒
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934.
Mike Saltmarsh 《Journal of the science of food and agriculture》2015,95(4):649-652
The E number system for food additives was introduced in the 1960s and the E was intended to reassure consumers that permitted additives were safe. In the 1980s full ingredient declarations had to be provided on food products for the first time and manufacturers were permitted to use either the name or the number of the additive on the ingredient list. This paper outlines some of the trends in the sourcing, use and labelling of additives since the introduction of full ingredient listing. Generally, sourcing has become more global with a large number of suppliers being based in China. From an initial use of E numbers in ingredient lists, manufacturers are increasingly using the names of additives. This trend is being extended to avoid the use of anything the consumer might consider an additive, particularly in connection with colours and preservatives. Specifically, the colours used in the Southampton study on the impact of food colours on hyperactivity in children have largely been replaced by colouring foodstuffs, and the preservative used in the study, sodium benzoate, has been replaced by potassium sorbate in the majority of soft drinks. © 2014 Society of Chemical Industry 相似文献
935.
Mike W. Humphreys Sally A. O'Donovan Markku S. Farrell Alan P. Gay Alison H. Kingston‐Smith 《Food and Energy Security》2014,3(2):98-110
The field performance and potential future use of F1 Lolium multiflorum and Lolium perenne × Festuca arundinacea var. glaucescens and Festuca mairei hybrids (2n = 4x = 28) are described. Foliar trait expression in the hybrids was largely determined by the Lolium rather than their Festuca parent ensuring maintenance of high‐forage quality. All four Festulolium populations comprised high‐yielding genotypes, but the L. multiflorum populations were particularly erect and tall, while the L. perenne populations had significantly higher numbers of tillers and were prostrate. Forage yields of the Festulolium populations assessed in field plot trials were either not significantly different from, or were superior to leading L. multiflorum and L. perenne cultivars used as controls. Endogenous plant proteases contribute to excessive proteolysis in the rumen which causes environmental N pollution. Protein degradation due to plant‐mediated proteolysis was assessed by in vitro exposure of leaves to the environmental conditions of the rumen (39°C, anaerobic) and calculated based on the time taken for protein levels to be reduced to half their original levels (t½). Leaf proteins were significantly more stable in L. multiflorum × F. arundinacea var. glaucescens and L. perenne × F. arundinacea var. glaucescens F1 hybrids (t½ 18–21 h) than in their respective Lolium parental genotypes (t½ 4–5 h), and there was a highly significant genome interaction. The t½ in the majority of the L. multiflorum × F. arundinacea var. glaucescens F1 hybrids studied often exceeded 24 h, whereas t½ of their Lolium and Festuca parents was consistently <14 h. Although inferior to the F1, F. arundinacea var. glaucescens genotypes tested had significantly greater t½ than L. perenne under rumen‐simulated conditions. Significant variation in protein stability was apparent within the F1 and their respective parent species' groups. The initial protein content of the F1 hybrids was lower than their respective parents, but following 24‐h exposure to anoxia at 39°C, the protein content of both parent and hybrid genotypes was similar. The differences in protein stability between parental and hybrid genotypes was due to the greater rate of protein decline observed in the Lolium genotypes. Hence, uptake of these Festulolium hybrids as forage crops has potential to directly mitigate environmental impact of livestock farming without affecting production capacity. 相似文献
936.
937.
Mike Beanie Sara Jones Jill Hewitt John Sapsford-Francis 《New Review of Hypermedia and Multimedia》2013,19(1):69-87
Abstract Advice systems are defined as information systems which present users with both information and more subjective expert advice about complex and weakly structured domains. This paper presents a Generic Advice System Architecture (GASA) to assist in developing such systems. It describes how the architecture was used in developing the SPIRE system, whose aim is to provide advice and information which will assist the integration of students with disabilities into higher education. The paper discusses the way in which the GASA addresses key issues in the development of hypermedia advice systems including the need to make such systems available to users with little training and limited knowledge of the domain; the requirement to support diverse information exploration strategies; the provision of purely ‘point and select access; ’ and the minimisation of user disorientation and cognitive overhead. 相似文献
938.
Charlotte N. Dunford Mike Yearworth Darren M. York Patrick Godfrey 《Systems Engineering》2013,16(2):134-151
The purpose of the study was to gain a greater understanding of the use of Systems Practice among engineers working in the Rolls‐Royce Defence Sector at its Bristol site and develop hypotheses about its use. This study is part of a larger project to investigate and improve the use and embedding of Systems Practice among engineers at the site. The current situation was studied using a combination of grounded theory and system dynamics, supported by the use of a computer‐aided qualitative data analysis software (CAQDAS) package. The results from this work show that Systems Practice is valued as a way of enabling quality in design but engineers find it challenging to adopt because of (i) lack of stakeholder appreciation of its value, (ii) their lack of experience with Systems Engineering, and (iii) logistical issues with its application. This work will be followed by group model building sessions to further develop the findings by identifying interventions to create and assess improvement in Systems Practice, in particular finding errors earlier in the design lifecycle. ©2012 Wiley Periodicals, Inc. Syst Eng 16 相似文献
939.
Mike King 《Digital Creativity》2013,24(4):215-227
3D computer graphics has been under-used by fine artists. This paper explores some of the possible reasons for this and also some of the possible attractions of 3D. The rigid depiction of three-space, as performed so accurately by the camera, had been a goal of painters since the Renaissance, but in the twentieth century a host of factors led to its subversion. Only in the sixties and in the US did a photorealist painting become popular. The author suggests that linear perspective has been seen as a tyranny, but the time has come to re-evaluate and liberate it through 3D computer graphics as a medium for fine art. The author's own work using ray-tracing software is described. 相似文献
940.
Mike Phillips 《Digital Creativity》2013,24(1):48-57
Fulldome is slowly emerging from its planetarium shaped incubator into a brave new world of digital projectors, real-time visualisation software, independent content producers and transdisciplinary collaborations. This article takes a slow zoom through the evolution of fulldome. It reflects on the technologies and institutions that have shaped the fulldome orthodoxy and the recent emergence of a digital framework where all the different kinds of technologies, disciplines and media forms fit together. The fulldome may no longer be full of stars, but the emptiness that lies beyond its domed surface offers new imaginings of a ‘future in space’. 相似文献