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Empowering women farmers to participate in agricultural research is a key strategy for sustainable agricultural development. Women empowerment has the potential to improve their roles in agricultur...

In 2012, Africa RISING conducted participatory community analysis (PCA) as the first phase of a participatory development approach in the Ethiopian highlands. The PCA identified trends, constraints...

There is a limited understanding of the lotic macroinvertebrate fauna of West Africa, although many watercourses are heavily impacted. Macroinvertebrates were sampled from a stream running through Accra, the capital of Ghana, to provide information on the nature of these communities and their response to pollution. The physicochemical pollution gradient in the stream was reflected in the macroinvertebrate community, which showed a similar response to that observed in well studied temperate areas. Heavily polluted sites within the city supported a poor fauna and were dominated by tolerant taxa, such as the Chironomidae. The success of the macroinvertebrate fauna in revealing the pollution gradient and discriminating between sites suggest that there is potential for biological monitoring in such situations.

Summary The comparative morphology of the foregut during development from embryonic larva to adult in Cherux quadricarinatus was examined by light and scanning electron microscopy. Major ontogenetic changes occurred in the gastric mill dentition in terms of denticle shape, appearance of vertical ridges in the lateral teeth, roughness of masticating surfaces, degree of sclerotization and proportional sizes of the median tooth components. Natural food types appropriate for the various life history stages during artificial rearing of C. quadricarinatus may be inferred from the morphology of the gastric mill dentition of those stages. Cardiopyloric valves and the gland filter appeared prior to development of functional gastric mill teeth. Compared with the foregut of adult astacid crayfish, that of adult C. quadricarinatus shows differences in the ventral cardiopyloric valve, pyloric funnel and lateral valves.

(1945). A Property of Appell Sets. The American Mathematical Monthly: Vol. 52, No. 4, pp. 191-193.