We study the cross-country evolution of technology diffusion processes. Using data from the last two centuries for twenty-five major technologies, we document two new facts: there has been convergence in adoption lags between rich and poor countries, while there has been divergence in long run penetration rates, once technologies are adopted. We show that the evolution of aggregate productivity...

Few days ago our advisory editorial board member Prof. Gholam A. Peyman was named as one of the 12 eminent researcher recipients of the National Medal of Technology and Innovation in US. Eleven extraordinary inventors were also named recipients of the National Medal of Technology and Innovation. This award and the National Medal of Science designations are the uppermost honors bestowed by the f...

All truths are easy to understand once they are discovered; the point is to discover them. A sthma, a chronic inflammatory lung condition with acute episodes of bronchoconstriction and exacerbation, is associated with considerable patient morbidity, a diminution of productivity, and an increase in health-care utilization. Throughout the 1980s and 1990s, there was a clear perception that asthma ...

abstract: iran passed wide range of events over her controversies history. it has great special geopolitics position, natural resources and cultural values. iran is in asia and connects asia to europe. iran as relational bridge has an important role so that it could be an important center during first and second world war for enemies' forces in spite of explicit neuter declaration from ira...

background: during the month of ramadan, millions of muslims abstain from food and drink daily from dawn to sunset and people actually experience repeated cycles of fasting and refeeding. menstruation is a normal physiological process that its regularity is controlled by hypothalamic-pituitary-ovarian axis. etiology of menstrual dysfunction includes weight loss, hypoleptinemia, abnormal eating ...