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Large‐scale manufacture of nitrogen fertilizers in India originated during the Second World War as a result of the interruption of the import of rice from Burma. The growth of production has been at the prodigious rate of 22 per cent per annum in the 17‐year period 1949/50–1965/6. Demand has never acted as a constraint; this suggests that agro‐industry can play an important part in an industrializing strategy for development. In spite of this success two negative features have characterized the economic history of fertilizer production: gestation lags and under‐utilized capacity. Had the establishments worked at design capacity and had the average gestation lag not exceeded three years, less than 60 per cent of the 2.1 million tons of nutrient imported into India during these 17 years would have been required. This highlights the need to include in planning models of output expansion both of these variables, getstation lag and low capacity utilization. Some of their causes have been exogenous to the industry. But a number are internal and recurrent. Unjustified technical risks, plant dis‐integration, faulty process selection and inadequate project appraisal in investment decision‐making. Attempts to reduce the balance of payments deficit have had a negative feedback on the foreign exchange flow by reducing the industry's average annual output. Such negative effects should be included in formulating import control, import substitution and export promotion policies. Finally the ubiquity of excess capacity and the invariance of labour force size with the degree of capacity utilization in this sector is shown to lead to large over‐estimates of the future required‐labour force when certain forecasting techniques are used, even in the absence of trends to increasing labour productivity.  相似文献   
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A scant literature has identified gun carrying as a potential risk factor for victimization at the individual level. To date, however, research has generally focused on high-risk individuals rather than samples drawn from the general population. Additionally, prior studies have not often enough included controls robust enough to feel strongly that the relationship between gun carrying and victimization, gun victimization in particular, is not simply the spurious outcome of factors that influence both variables. The current study uses data from Add Health participants (N = 13,568) to look at the effect of gun carrying on gun victimization among adolescents. Results suggest that even when robust controls are considered, a measure of gun carrying significantly and positively correlates with gun victimization. The results support a model of the gun carrying-gun victimization relationship wherein gun carrying increases risks for gun victimization independent of factors that may influence both risky behaviors and victimization. Implications for theory and policy are discussed.  相似文献   
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