A Quasi-Classical Model of Intermediate Velocity Particle Production in Asymmetric Heavy Ion Reactions

The particle emission at intermediate velocities in mass asymmetric reactions is studied within the framework of classical molecular dynamics. Two reactions in the Fermi energy domain were modelized, $^{58}$Ni+C and $^{58}$Ni+Au at 34.5 MeV/nucleon. The availability of microscopic correlations at all times allowed a detailed study of the fragment formation process. Special attention was paid to the physical origin of fragments and emission timescales, which allowed us to disentangle the different processes involved in the mid-rapidity particle production. Consequently, a clear distinction between a prompt pre- equilibrium emission and a delayed aligned asymmetric breakup of the heavier partner of the reaction was achieved.Comment: 8 pages, 7 figures. Final version: figures were redesigned, and a new section discussing the role of Coulomb in IMF production was include

Estimating household demand for millet and sorghum in Niger and Nigeria, Series Paper Number 39

Millet and sorghum are two important crops and source of calories for poor households in semiarid West and Central Africa. This research analyzes the response of household demand for millet and sorghum to income and prices in Niger and Nigeria using the latest Living Standards Measurement Study-Integrated Surveys on Agriculture (LSMS-ISA) data by a two-stage method. In the first stage, a Working-Leser model is estimated to obtain the elasticity of food expenditure with respect to household total expenditure. In the second stage, a Quadratic Almost Ideal Demand System (QUAIDS) model, incorporating household socio-demographic characteristics and regional dummy variables, is estimated for rural and urban households separately. Unconditional expenditure elasticities, own-price elasticities, and cross-price elasticities are obtained by combining the results of first and second stages. Results reveal that millet and sorghum are necessities for households in Niger and Nigeria. As income grows, household demand for the two crops will increase but at a lower rate than income growth in both countries. Demand for sorghum and millet among rural households is less responsive to income and price changes compared with urban households. Considering high population growth rate and increasing urbanization rate in the two countries, it is expected that total demand for millet and sorghum will continue to increase, but their share in household’s food budget will decline

The Impact of Biofortified Iron Bean Adoption on Productivity, and Bean Consumption, Purchases and Sales

This study evaluates the treatment effect of adoption of biofortified iron beans in Rwanda on household yields, bean consumption from own-production and purchases, bean sales, and the probability of being a net seller of beans. Because the adoption decision could be endogenous to these outcomes, we use an instrumental variable approach to quantify the impacts of adoption. Some of the iron bean varieties provide yield gains (measured as multiplication ratio, i.e. quantity harvested/quantity planted) of 19-25% over traditional varieties. Iron bean adoption also increases household consumption of own-produced beans by 14%. It reduces the probability of purchasing beans to meet consumption needs by 13% and reduces total purchases by 3.9 kg per adult equivalent on average. Finally, adoption increases the probability that a household sells beans by 16% and increases the probability that it is a net seller of beans by 14%. These findings are promising for the continued adoption of iron beans in Rwanda and elsewhere and provide evidence that biofortified crops are a good investment for nutrition, food security, and poverty reduction