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Postharvest management is critical to attaining household food, nutrition, and income security. Hermetic grain storage bags offer an effective pesticide-free way to protect stored grain against fungal and insect infestation. We evaluated articles indexed in the Web of Science that included experiments comparing the storage efficacy of conventional and hermetic storage bags based on grain germination rate, insect infestation, physical damage, mycotoxin contamination, and changes in weight and moisture content. Compared with grain stored in hermetic bags, grain stored in conventional bags lost 3.6-fold more seed viability, contained 42-fold more insects, had 11-fold more physical damage, and lost 23-fold more grain weight, while grain moisture levels were similar for both hermetic and conventional storage bags. Mycotoxin contamination levels were not as frequently assessed. Levels could be low in grain stored in both types of bags, or levels could be low in hermetic bags and significantly higher in conventional bags. The improved properties of grain stored in hermetic bags can increase food security and household income by providing safe storage options for maintaining seed germinability, and for consumption and/or sale when food supplies are high, or when prices are low. Hermetic bags are economically feasible for use by subsistence farmers in Sub-Saharan Africa for grain for household consumption and for carrying-over seed for planting in the next season. Additional studies are needed to verify the mycotoxin contamination results and to determine if there are differences in functional food characteristics, e.g. flavor and cooking properties, that have not been as comprehensively studied. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
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The hypothesis tested was that "clients whose behavior when asked to free associate is highly variable, flexible, or productive exhibit significantly greater variability when judging the extent of autokinetic movement on successive trials than Ss whose behavior at the outset of psychotherapy is highly inflexible, stereotyped, or rigid." 7 neurotic college student analysands in the extremely flexible group were matched with 10 Ss of the extremely rigid group for relevant personal variables. Sherif's autokinetic apparatus was used, and each S's judgmental variability was determined. The highly significant difference between autokinetic variability scores of the 2 groups lends strong support to the hypothesis. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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An experimental group (N = 19) was trained to receive Morse code with signals that were weighted with respect to frequency of presentation in rough proportion to their order of difficulty for beginners. A control group (N = 19), matched on a code aptitude test performance, was trained with each signal presented an equal number of times. On the test runs, no significant differences were observed in the progress of the two groups. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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The writer summarises his researches in the field of polymer science. He began with studies of the structures of space-network and sheet polymers in crystals. Currently he is working on the structures of macro-ions in silicate and borate crystals and glasses and on the development of a new theory of structures and thermodynamic properties of (polymer and other) solutions.  相似文献   
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