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41.
Gudrun B. Keding John M. Msuya Brigitte L. Maass Michael B. Krawinkel 《Food Security》2012,4(1):129-140
The objective of the present study was to measure diversity in nutrition with dietary scores, and to assess their relationship
to vegetable production and the socio-economic status of women in rural Tanzania. A dietary diversity score (DDS) and a food
variety score (FVS) were created from data gathered with three semi-quantitative 24-h recalls performed during three non-consecutive
seasons during 2006/2007. Data on vegetable production, selling and buying and socio-economic data was gathered with a semi-quantitative
questionnaire. A total of 252 randomly selected women from three districts of north-eastern and central Tanzania participated.
The median DDS of 6 and the mean FVS of 8.3 were low, suggesting an overall poor dietary quality, with about one third of
participants having an alarmingly low DDS of only two to four food groups per day. These women consumed a very basic diet
consisting mainly of cereals and vegetables. Differences among districts were pronounced while those among seasons were less
distinct. The DDS and FVS were both significantly associated with ethnicity, occupation and status within the household of
participants. As a more varied diet is not necessarily healthier, integration of both quantity and quality in the scores is
proposed for future studies. This can be achieved, for example, by weighing food types according to their importance in the
diet. As both scores are linked to the production, selling and buying of vegetables, the promotion of homestead food production
may be a good way to improve dietary diversity. 相似文献
42.
This study identified practices, preferences, attitudes and decision-making for fruit consumption, fruit production, and use of income generated from these activities and assessed the contribution of fruits to closing nutritional gaps of members of smallholder farming households in Western Kenya during two different seasons. Two cross-sectional surveys were conducted, one in July/August 2013 (S1) and the other in February/March 2014 (S2). The same respondents, women responsible for food preparation in the household, were interviewed during S1 and S2 with a total of 272 women participating. Semi-structured questionnaires were used to collect data on practices, preferences and attitudes related to fruit production and consumption including a quantitative 24-h recall. On the day prior to the interview, only 25% of women during S1 and 37% during S2 had consumed fruits. Fruit consumption in grams per day differed significantly (p < 0.001) between the two seasons and was higher in S2 (mean = 106 g/d; SD = 208 g/d) compared to S1 (mean = 49 g/d; SD = 101 g/d). During both seasons, 80% or more respondents did not reach the recommended amount of 200 g of fruits per day and also had low vitamin A and C intakes, especially during S1. Simultaneously, 80% of women indicated that the household grew fruit, yet fruit production and consumption diversity were low. About 20% of respondents identified fruit consumption taboos for different household members and 37% viewed the consumption of wild fruits negatively. Integrated agriculture-nutrition programs should consider local practices, preferences and cultural attitudes in order to promote the consumption of a diversity of nutrient rich fruits and consequently better diets and nutrition. 相似文献
43.
Lofts S Chapan PM Dwyer R McLaughlin MJ Choeters I Sheppard SC Adams WJ Alloway BJ Antunes PM Campbell PG Davies B Degryse F De Vries W Farley K Garrett RG Green A Jan Groenenberg B Hale B Harrass M Hendershot WH Keller A Lanno R Liang T Liu WX Ma Y Menzie C Moolenaar SW Piatkiewicz W Reimann C Rieuwerts JS Santore RC Sauvé S Schuetze G Schlekat C Skeaff J Smolders E Tao S Wilkins J Zhao FJ 《Environmental science & technology》2007,41(18):6326-6331
44.
Production and processing of foods as core aspects of nutrition-sensitive agriculture and sustainable diets 总被引:1,自引:0,他引:1
Some forms of malnutrition are partly due to agriculture not having nutrient outputs as an explicit goal. A better understanding of what is required from agricultural production and food processing for healthy and sustainable diets is needed. Besides nutritional quality or nutrient output, important factors are: water, soil, health hazards, agrobiodiversity and seasonality. Therefore, possible interactions among constituents of the food chain – human health, the environment, knowledge and education – should be considered from a systemic perspective. Nutrition-sensitive agriculture needs to consider and understand the role of biodiversity in improving dietary quality and dietary diversity as well as seasonality in food supply. Apart from improving agricultural systems in order to close the nutrition gap, efficient storage and food processing technologies to prolong shelf-life are required. If processing is poor, high food losses can cause food insecurity or increase the risk of producing unsafe and unhealthy food. Food storage and processing technologies, particularly at household level, are challenging and often not applicable to traditional crops. In order to achieve the aims of nutrition-sensitive agriculture, it is necessary to comprehend its complexity and the factors that influence it. This will require a trans-disciplinary approach, which will include the three sectors agriculture, nutrition and health at research, extension and political levels. Ensuring that farmers are knowledgeable about production systems, which sustainably provide adequate amounts of nutritious food while conserving the environment is an essential part of nutrition-sensitive agriculture. At the same time, for the benefits of nutrition-sensitive agriculture to be realized, educated consumers are required who understand what constitutes a healthy and sustainable diet. 相似文献
45.
Frank Hemberger Sebastian Weis Gudrun Reichenauer Hans-Peter Ebert 《International Journal of Thermophysics》2009,30(4):1357-1371
Novel graded carbon aerogels were synthesized to study the impact of different synthesis parameters on the material properties
on a single sample and to test a new, locally resolved thermal-conductivity measurement technique. Two identical cylindrical
aerogels with a graded structure along the main cylindrical axis were synthesized. Along the gradient with an extension of
about 20 mm the densities range from 240 kg·m−3 to 370 kg·m−3 and the effective pore diameter determined via small angle X-ray scattering and SEM increase systematically from 70 nm up
to 11,000 nm. One specimen was cut perpendicular to the cylinder axis into disc-shaped samples; their thermal conductivities
in an argon atmosphere, as determined via a standard laser-flash technique, range from 0.06W·m−1·K−1 to 0.12W·m−1·K−1 at 600 °C. The second specimen, cut to obtain a sample with the gradient in-plane, was investigated with a spatially resolved
laser-flash technique at ambient conditions. The results of the two different techniques are compared and discussed in detail. 相似文献
46.
The molecular parameters of the flocculation agent from polyacrylonitrile and dicyandiamide (PAN-DCD) were determined in dimethylsulfoxide. In acidic and alkaline aqueous solutions (0.1 N) PAN-DCD is weakly aggregated, additionally a small fraction of polymer exists as highly aggregated particle component. A shift of the pH-value in direction to the neutral range leads immediately to particle growth, which is finished at pH 3, coming from the acidic range and pH 10, coming from the alkaline one. After the passage of the neutral range disaggregation occurs. Flocculation can also be induced by addition of salt. The structural parameters of the particles were determined by a detailed analysis of the light scattering curves. Results obtained give information about the flocculation mechanism. 相似文献
47.
Ann-Charlotte Eliasson Gudrun Ljunger 《Journal of the science of food and agriculture》1988,44(4):353-361
The retrogradation of waxy maize starch in the presence of surfactants and emulsifiers was measured by differential scanning calorimetry. It was found that a surfactant (cetyltrimethylammonium bromide) and unsaturated monoglycerides reduced retrogradation, whereas lecithin and a soya bean oil influenced the retrogradation to a lesser extent. The effects were greater after 1 day of storage than after 7 days, and the influence of the surfactant was greater at +25oC than at +7oC. Different storage temperatures led to crystallised forms of amylopectin with different melting temperatures. Further, an amylopectin sample was affected by the presence of a surfactant in a way similar to the waxy maize starch. 相似文献
48.
Copolymers of AN were prepared with variable molecular masses and with variable contents of methylacrylate (ASME) and sodiumallylsulfonate (NaAS), acrylamide (AA), itaconic acid (IS), polyethyleneglycol acrylate (600) (PEGA), vinylacetate (VA), 2-hydroxyethyl acrylate, (HEE) or sodium acrylamido-2-methylpropanesulfonate (NaAMPS), respectively, by using a mathematical model for the calculation of the polymerization conditions needed. Precipitation studies by light scattering showed the predominant influence of NaAS and NaAMPS on the precipitation properties. Acrylonitrile homopolymers show a hard precipitation behaviour. The originating particles have a density of between 0.2 and 0.4 g/cm3. An increasing content of NaAS or NaAMPS leads for example beginning from 0.8 wt.-% NaAS in the monomer composition to a soft precipitation behaviour and to highly swollen particles possessing a density of less than 1 · 10?2 g/cm3. The molar mass and the ASME-content show no significant influence. For the acrylonitrile/acrylamide system already 0.5 wt.-% allylsulfonate is sufficient to get a soft precipitation behaviour with formation of highly swollen particles. All samples with the other cocomponents and without NaAS- or NaAMPS-comonomer show a hard precipitation behaviour with little swollen particles. 相似文献
49.
Wolfgang Schwack Gudrun Kopf 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1993,197(3):264-268
In order to study the photoreactivity of pirimicarb (2-(dimethylamino)-5,6-dimethyl-pyrimidin-4-yl-N-dimethylcarbamate) on plant surfaces, model experiments with organic solvents were performed. Pirimicarb decomposed readily when irradiated (>280 nm) in the presence of the selected model solvents to form a number of products. Half-lives were in the order isopropanol N-formylpirimicarb and, in a second step, toN-desmethylpirimicarb as well as to further oxygenated products with the carbamate moiety intact. Photolysis in cyclohexene resulted in photomi-neralisation as the main degradation pathway. Irradiation of pirimicarb in the presence of isopropanol also yielded an addition product of the parent compound with the secondary alcohol.
Photoabbau des Carbamat-Insecticids Pirimicarb
Zusammenfassung Zur Untersuchung des photochemischen Verhaltens von Pirimicarb auf Pflanzenoberflächen wurden Modellexperimente mit organischen Lösungsmitteln durchgeführt. Die Bestrahlung (>280 nm) von Pirimicarb in den ausgewählten Modellösungsmitteln führte zu einem raschen Abbau unter Bildung zahlreicher Produkte. Die Halbwertszeit für den Photoabbau in den einzelnen Lösungsmitteln stieg in der Reihenfolge Isopropanol相似文献
50.
Summary: An organic‐inorganic hybrid material consisting of a 3‐(methacryloxy)propyl functionalized SiO2/MgO framework was synthesized. This hybrid was successfully reacted with styrene, butyl acrylate and butyl methacrylate via a free radical emulsion polymerization to form polymer composites. The polymer composites were investigated by means of FT‐IR spectroscopy, TGA, DSC and rheometry. It is shown that the polymer is linked covalently to the organic/inorganic hybrid. Although the polymer content is rather low, the composites exhibit a polymer‐like character and enhanced mechanical properties compared to the corresponding homopolymers.