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.
Its population has undergone rapid urbanisation over the last 50 years, changing from being mostly rural at the time of independence in the 1960s to the point that the share of urban population as a percentage of total population was estimated at about 40% in 2010, with an average growth rate of 5% per year.