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.
The Changing Demographic Profile of the United States. Congressional Research Service 4. Figure 2 and the Appendix (at end of this report), in addition to highlighting the estimated and. projected trends in population growth for the period 1950-2050, also highlight trends and.