Is AIDS in Africa a distinct disease?

In Africa, opportunistic infections, transmission patterns, and viral subtypes differ from what is seen in the AIDS epidemics of the United States and Europe, yet 2 decades into the epidemic, AIDS researchers have only a shaky handle on the fundamental question: What accounts for these differences? The answers have potentially important implications for both prevention and treatment strategies.     

When are two heads better than one and why?

A recent study, using a perceptual task, indicated that two heads were better than one provided that the members could communicate freely, presumably sharing their confidence in their judgments. Capitalizing on recent work on subjective confidence, I replicated this effect in the absence of any dyadic interaction by selecting on each trial the decision of the more confident member of a virtual dyad. However, because subjective confidence monitors the consensuality rather than the accuracy of a decision, when most participants were in error, reliance on the more confident member yielded worse decisions than those of the better individual. Assuming that for each issue group decisions are dominated by the more confident member, these results help specify when groups will be more or less accurate than individuals.     

Crop–livestock interactions in agricultural and pastoral systems in West Africa

Driven by population pressures on natural resources, peri-urban pastoralists in the Far North Province of Cameroon have recently intensified livestock production in their traditional pastoral system by feeding their cattle cottonseed cakes and other agricultural byproducts to cope with the disappearance of rangelands typically available through the dry season. Although the crop–livestock interactions in this altered intensive pastoral system seem similar to alterations recently named in mixed-farming systems in West Africa, they are distinctly different and would require a different type of agricultural development support. I use Bourdieu’s theoretical constructs of “habitus” and “capital” to explain those differences.