Cession

The act of cession is the assignment of property to another entity. In international law it commonly refers to land transferred by treaty. Ballentine's Law Dictionary defines cession as "a surrender; a giving up; a relinquishment of jurisdiction by a board in favor of another agency" In contrast with annexation, where property is forcibly given up, cession is voluntary or at least apparently so.

Examples

In 1790, the U.S. states of Maryland and Virginia both ceded land to create the District of Columbia, as specified in the U.S. Constitution of the previous year. The Virginia portion was given back in 1847, a process known as "retrocession".

Following the First Opium War (1839–1842) and Second Opium War (1856–1860), Hong Kong (Treaty of Nanking) and Kowloon (Convention of Peking) were ceded by the Qing dynasty government of China to the United Kingdom; and following defeat in the First Sino-Japanese War, Taiwan was ceded to the Empire of Japan in 1895.

Territory can also be ceded for payment, such as in the Louisiana Purchase and Alaska Purchase.

Committed dose

The committed dose in radiological protection is a measure of the stochastic health risk due to an intake of radioactive material into the human body. Stochastic in this context is defined as the probability of cancer induction and genetic damage, due to low levels of radiation. The SI unit of measure is the sievert.

A committed dose from an internal source represents the same effective risk as the same amount of effective dose applied uniformly to the whole body from an external source, or the same amount of equivalent dose applied to part of the body. The committed dose is not intended as a measure for deterministic effects such as radiation sickness which is defined as the severity of a health effect which is certain to happen.

The radiation risk proposed by the International Commission on Radiological Protection (ICRP) predicts that an effective dose of one sievert carries a 5.5% chance of developing cancer. Such a risk is the sum of both internal and external radiation dose.