Urbanization: The process whereby a society changes from a rural to an urban way of life. It refers also to the gradual increase in the proportion of people living in urban areas.Urban Renewal: The planned upgrading of a deteriorating urban area, involving rebuilding, renovation, or restoration. It frequently refers to programs of major demolition and rebuilding of blighted areas.Urban Population: The inhabitants of a city or town, including metropolitan areas and suburban areas.Cities: A large or important municipality of a country, usually a major metropolitan center.Population Growth: Increase, over a specific period of time, in the number of individuals living in a country or region.Satellite Communications: Communications using an active or passive satellite to extend the range of radio, television, or other electronic transmission by returning signals to earth from an orbiting satellite.Urban Health: The status of health in urban populations.Economic Development: Mobilization of human, financial, capital, physical and or natural resources to generate goods and services.Rural Population: The inhabitants of rural areas or of small towns classified as rural.Topography, Medical: The systematic surveying, mapping, charting, and description of specific geographical sites, with reference to the physical features that were presumed to influence health and disease. Medical topography should be differentiated from EPIDEMIOLOGY in that the former emphasizes geography whereas the latter emphasizes disease outbreaks.Population Density: Number of individuals in a population relative to space.Gross Domestic Product: Value of all final goods and services produced in a country in one year.Conservation of Natural Resources: The protection, preservation, restoration, and rational use of all resources in the total environment.Lakes: Inland bodies of still or slowly moving FRESH WATER or salt water, larger than a pond, and supplied by RIVERS and streams.City Planning: Comprehensive planning for the physical development of the city.Ecosystem: A functional system which includes the organisms of a natural community together with their environment. (McGraw Hill Dictionary of Scientific and Technical Terms, 4th ed)Population Dynamics: The pattern of any process, or the interrelationship of phenomena, which affects growth or change within a population.Sanitation: The development and establishment of environmental conditions favorable to the health of the public.Sparrows: The family Passeridae comprised of small, mainly brown and grey seed-eating birds with conical bills.Slovakia: Created 1 January 1993 as a result of the division of Czechoslovakia into the Czech Republic and Slovakia.TaiwanRivers: Large natural streams of FRESH WATER formed by converging tributaries and which empty into a body of water (lake or ocean).Developing Countries: Countries in the process of change with economic growth, that is, an increase in production, per capita consumption, and income. The process of economic growth involves better utilization of natural and human resources, which results in a change in the social, political, and economic structures.Geography: The science dealing with the earth and its life, especially the description of land, sea, and air and the distribution of plant and animal life, including humanity and human industries with reference to the mutual relations of these elements. (From Webster, 3d ed)Agriculture: The science, art or practice of cultivating soil, producing crops, and raising livestock.Poverty Areas: City, urban, rural, or suburban areas which are characterized by severe economic deprivation and by accompanying physical and social decay.Socioeconomic Factors: Social and economic factors that characterize the individual or group within the social structure.China: A country spanning from central Asia to the Pacific Ocean.World Health: The concept pertaining to the health status of inhabitants of the world.Social Change: Social process whereby the values, attitudes, or institutions of society, such as education, family, religion, and industry become modified. It includes both the natural process and action programs initiated by members of the community.BrazilDenitrification: Nitrate reduction process generally mediated by anaerobic bacteria by which nitrogen available to plants is converted to a gaseous form and lost from the soil or water column. It is a part of the nitrogen cycle.Prevalence: The total number of cases of a given disease in a specified population at a designated time. It is differentiated from INCIDENCE, which refers to the number of new cases in the population at a given time.