Iranian traditional architecture is one of the world's architectures par excellence. It was one of the most important architectures in the medieval Islamic world. Iranian architecture has developed over millennia in response to its religion. Many traditional and vernacular buildings in Iran show that the architects had been so clever in harmonizing the Iranian religion and architecture in the p...

In a rural district hospital in Kenya, the authors screened 100 randomly selected outpatients for khat (miraa) chewing. A surprisingly high number of them admitted chewing khat leaves. The implications of this finding and the controversy about whether or not khat is a harmful drug are discussed.

Coarse Particles and Dust Storm Mortality In a paper titled "Episodes of High Coarse Partide Concentrations Are Not Associated with Increased Mortality," Schwartz et al. (1) concluded that "coarse particles from windblown dust are not associated with mortality risk." The authors seem to have overlooked the medical literature on the health effects of the historic U.S. dust storms of the dust bow...

We show that strictly abnormal geodesics arise in graded nilpotent Lie groups. We construct such a group, for which some Carnot geodesics are strictly abnormal and, in fact, not normal in any subgroup. In the 2-step case we also prove that these geodesics are always smooth. Our main technique is based on the equations for the normal and abnormal curves, that we derive (for any Lie group) explic...

Referral of extremely low birthweight infants (less than 1001 g) from district hospitals in a geographically defined area to a specialist regional centre significantly improved their chances of survival.