Introduction. Beta-blockers, also known as beta-adrenoceptor blocking agents, are medications used to treat conditions such as angina, heart failure and high blood pressure. They decrease the activity of the heart by blocking the action of hormones like adrenaline.
1 The concept of âdemographic changeâ describes a populationâs age structure adjusting to. changes in living conditions. Consequently, changes in thcomposition of a societyâe s age. structure are the result of social shifts. (. 2  cf. . 3  theory of first and second demographic transition.
November 21, 2014. The sweeping racial changes transforming the United States come with an important demographic dimension: age. The waves of Hispanics and Asians and multiracial Americans reshaping the countryâs population are full of young people, who by some measures already outnumber their white counterparts.