in the x direction, the water wants to flow in that direction) For a given hydraulic. conductivity, the vertical flow rate depends on the sum of the gravitational potential energy. gradient per unit weight of water (dz/dz =1) and the vertical gradient in soil water pressure.
Origin and spread of the 1278insTATC mutation causing TayâSachs disease in Ashkenazi Jews: Genetic drift as a robust and parsimonious hypothesis. Human Genetics 114 (4): 366â376. pmid 14727180.
Tay-Sachs disease occurs most frequently among people whose ancestors come from Eastern and Central European Jewish communities (Ashkenazi Jews), from certain French Canadian communities in Quebec, the Old Order Amish community in Pennsylvania and from the Cajun community of Louisiana.