BorderBorders are usually defined as geographical boundaries, imposed either by features such as oceans and terrain, or by political entities such as governments, sovereign states, federated states, and other subnational entities. Political borders can be established through warfare, colonization, or mutual agreements between the political entities that reside in those areas; the creation of these agreements is called boundary delimitation.
Border controlBorder control refers to measures taken by governments to monitor and regulate the movement of people, animals, and goods across land, air, and maritime borders. While border control is typically associated with international borders, it also encompasses controls imposed on internal borders within a single state. Border control measures serve a variety of purposes, ranging from enforcing customs, sanitary and phytosanitary, or biosecurity regulations to restricting migration.
Open borderAn open border is a border that enables free movement of people (and often of goods) between jurisdictions with no restrictions on movement and is lacking substantive border control. A border may be an open border due to intentional legislation allowing free movement of people across the border (de jure), or a border may be an open border due to a lack of legal controls, a lack of adequate enforcement or adequate supervision of the border (de facto).
European integrationEuropean integration is the process of industrial, economic, political, legal, social, and cultural integration of states wholly or partially in Europe or nearby. European integration has primarily come about through the European Union and its policies. In antiquity, the Roman Empire brought about integration of multiple European and Mediterranean territories. The numerous subsequent claims of succession of the Roman Empire, even the iterations of the Classical Empire and its ancient peoples, have occasionally been reinterpreted in the light of post-1950 European integration as providing inspiration and historical precedents.
Protein secondary structureProtein secondary structure is the local spatial conformation of the polypeptide backbone excluding the side chains. The two most common secondary structural elements are alpha helices and beta sheets, though beta turns and omega loops occur as well. Secondary structure elements typically spontaneously form as an intermediate before the protein folds into its three dimensional tertiary structure. Secondary structure is formally defined by the pattern of hydrogen bonds between the amino hydrogen and carboxyl oxygen atoms in the peptide backbone.
Regional integrationRegional Integration is a process in which neighboring countries enter into an agreement in order to upgrade cooperation through common institutions and rules. The objectives of the agreement could range from economic to political to environmental, although it has typically taken the form of a political economy initiative where commercial interests are the focus for achieving broader socio-political and security objectives, as defined by national governments.
