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951.
International experience of Policy Councils on food and nutrition has developed over recent decades but they have not received the attention that is due to them. The 1992 International Conference on Nutrition recommended that governments create Food Policy Councils but few have been created. There has been more experience in local and sub-national policy councils, particularly in North America. Developing country experience of attempting to improve food policy integration stems from the 1970s. The UK's House of Commons' (Parliamentary) Health Committee, in its 2004 report on obesity, reviewed current policy determinants of the rise in obesity, concluding that national food and health policy lacked coherence, integration and effectiveness. To address this vacuum, it proposed the creation of a new 'Council of Nutrition and Physical Activity to improve co-ordination and inject independent thinking into strategy'. The case for creating such a Council in the UK is reviewed, as are possible organisational options, functions and remit. A Council could be created under the forthcoming Public Health Act. The purpose of the new Council would be to provide independent advice and strategic advice as well as monitor the linkages between policies on food, nutrition and physical activity, noting their environmental implications. 相似文献
952.
Wegmann J Krucker M Bachmann S Fischer G Zeeb D Lienau A Glaser T Runge F Lüddecke E Albert K 《Journal of agricultural and food chemistry》2002,50(26):7510-7514
The core-shell structure of lycopene micronizates can be verified by employing a combination of solid-state and suspended-state NMR spectroscopy. The type of molecular aggregation of carotenoid nanoparticles can be clearly determined from their characteristic fingerprint pattern in the solid-state NMR spectra. 相似文献
953.
Anders R?bild Anders S?nderg?rd Larsen Jan Svejgaard Jensen Moussa Ouedraogo Sitske De Groote Patrick Van Damme Jules Bayala Boukary Ousmane Diallo Haby Sanou Antoine Kalinganire Erik Dahl Kjaer 《New Forests》2011,41(3):297-315
Fruit trees play an important nutritional role for livelihoods of rural people in the West African Sahel through provision of energy and nutrients such as vitamins, minerals, and proteins. Research on the domestication of local fruit trees has started recently through projects concentrating on some of the most important indigenous species of dry West Africa, i.e. Adansonia digitata, Parkia biglobosa, Tamarindus indica, Vitellaria paradoxa and Ziziphus mauritiana. We present a status of finalised and ongoing domestication research with the aim of defining research gaps that would need to be covered by future research activities to obtain higher yields and better quality fruits. Germplasm collection in central West Africa has been intense compared to elsewhere in the species?? distribution areas, but conservation status of the material is poor since it is only planted in few trials. Knowledge of genetic parameters, especially for fruit traits, is almost absent, but characterisation of genotypes is underway for some of the species. Mating systems and patterns are still unknown for many species. Efficient vegetative propagation based on simple techniques was shown to be possible for all species except P. biglobosa. In order to secure immediate as well as long term gains, we recommend combining clonal propagation of selected plus individuals with recombination and breeding of selected genotypes. We discuss whether local institutions in the Sahel have the financial capacity to carry out long term breeding programmes, and suggest that efforts should be made to find new ways of disseminating improved germplasm. 相似文献
954.
This study describes the physiological response of two co-occurring tree species (Eucalyptus marginata and Corymbia calophylla) to seasonal drought at low- and high-quality restored bauxite mine sites in south-western Australia. Seasonal changes in photosynthesis (A), stomatal conductance (g(s)), leaf water potential (ψ), leaf osmotic potential (ψ), leaf relative water content (RWC) and pressure-volume analysis were captured over an 18-month field study to (i) determine the nature and severity of physiological stress in relation to site quality and (ii) identify any physiological differences between the two species. Root system restriction at the low-quality site reduced maximum rates of gas exchange (g(s) and A) and increased water stress (midday ψ and daily RWC) in both species during drought. Both species showed high stomatal sensitivity during drought; however, E. marginata demonstrated a higher dehydration tolerance where ψ and RWC fell to -3.2 MPa and 73% compared with -2.4 MPa and 80% for C. calophylla. Corymbia calophylla showed lower g(s) and higher ψ and RWC during drought, indicating higher drought tolerance. Pressure-volume curves showed that cell-wall elasticity of E. marginata leaves increased in response to drought, while C. calophylla leaves showed lower osmotic potential at zero turgor in summer than in winter, indicating osmotic adjustment. Both species are clearly able to tolerate seasonal drought at hostile sites; however, by C. calophylla closing stomata earlier in the drought cycle, maintaining a higher water status during drought and having the additional mechanism of osmotic adjustment, it may have a greater capacity to survive extended periods of drought. 相似文献
955.
The neutralization reaction between an acid and a base in water, triggered after optical excitation, was studied by femtosecond vibrational spectroscopy. Bimodal dynamics were observed. In hydrogen-bonded acid-base complexes, the proton transfer proceeds extremely fast (within 150 femtoseconds). In encounter pairs formed by diffusion of uncomplexed photoacid and base molecules, the reaction upon contact was an order of magnitude slower, in agreement with earlier reported values. These results call for a refinement of the traditional Eigen-Weller picture of acid-base reactions: A three-stage model is introduced to account for all observed dynamics. 相似文献
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958.
Stokstad E 《Science (New York, N.Y.)》2002,296(5573):1589
959.
960.
Stokstad E 《Science (New York, N.Y.)》2008,320(5875):472