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The application of systems analysis to the study of agricultural distribution has far-reaching implications for marketing investigations and for managerial decision-making. Concepts developed in the emerging discipline of Physical Distribution Management are applicable to agricultural distribution, an area which has not hitherto been the subject of a systems approach which incorporates such concepts as ‘total distribution analysis’, ‘socio-technical systems’ and ‘synergy’. This paper demonstrates the scope for taking a systems analysis view of agricultural distribution and illustrates three of its aspects—namely, the marketing of farm inputs, the distribution of farm produce and machinery management on the farm.  相似文献   
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The concentrations of basophils in blood and bone marrow were monitored in guinea pigs subjected to primary and secondary infestations with larvae of Dermacentor andersoni. In these guinea pigs a significant increase of basophils was evident in peripheral blood. The response following the secondary infestation was more rapid and more intense than that following the primary infestation. Similar changes were also shown to occur in bone marrow. The possible significance of these responses in relation to acquired tick resistance in guinea pigs is discussed.  相似文献   
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A residual fumigant effect is demonstrated for fruit held 1 to 3 days within its cardboard carton after fumigation with 1,2-dibromoethane (EDB). This residual fumigant effect reduces significantly the dosage required for a specified level of control when compared with that required for fruit removed from the carton immediately after airing when fumigation is completed. The effect is due to the slow release of gas sorbed during fumigation and to the slow dispersion of this gas from the carton.  相似文献   
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Fractionation and reconstitution techniques were used to study the contribution of endogenous flour lipids to the quality of semisweet (Rich Tea-type) biscuits. Biscuit flour was defatted with chloroform and baked with bakery fat but without endogenous lipid addition. Semisweet biscuits baked from defatted flour were flatter, denser, and harder and showed collapse of gas cells during baking when compared with control biscuits. Defatted flour semisweet doughs exhibited a different rheological behavior from the control samples showing higher storage and loss moduli (G' and G' ' values), that is, high viscoelasticity. Functionality was restored when total nonstarch flour lipids were added back to defatted flour. Both the polar and nonpolar lipid fractions had positive effects in restoring flour quality, but the polar lipid fraction was of greatest benefit. Both fractions were needed for complete restoration of both biscuit quality and dough rheological characteristics.  相似文献   
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