background: unsustainable development of human societies, especially in arid and semi-arid areas, is one of the most important environmental hazards that require preservation of groundwater resources, and permanent study of qualitative and quantitative changes through sampling. accordingly, this research attempts to assess and analyze the spatial variation of quantitative and qualitative indica...

The recent evidence for neutrino oscillations stimulate us to discuss again the problem of fermion masses and mixings in gauge theories. In the standard model, several forms for quark mass matrices are equivalent. They become ansatze within most extensions of the standard model, where also relations between quark and lepton sectors may hold. In a seesaw framework, these relations can constrain ...