The Cambrian explosion, Cambrian radiation, Cambrian diversification, or the Biological Big Bang refers to an interval of time approximately 538.8 million years ago in the Cambrian Period of early Paleozoic when there was a sudden radiation of complex life and practically all major animal phyla started appearing in the fossil record. It lasted for about 13 – 25 million years and resulted in the divergence of most modern metazoan phyla. The event was accompanied by major diversification in other groups of organisms as well.Before early Cambrian diversification, most organisms were relatively simple, composed of individual cells, or small multicellular organisms, occasionally organized into colonies. As the rate of diversification subsequently accelerated, the variety of life became much more complex, and began to resemble that of today. Almost all present-day animal phyla appeared during this period, including the earliest chordates.A 2019 paper suggests that the timing should be expanded back to include the late Ediacaran, where another diverse soft-bodied biota existed and possibly persisted into the Cambrian, rather than just...

Dystonia is a neurological hyperkinetic movement disorder in which sustained or repetitive muscle contractions result in twisting and repetitive movements or abnormal fixed postures. The movements may resemble a tremor. Dystonia is often intensified or exacerbated by physical activity, and symptoms may progress into adjacent muscles.The disorder may be hereditary or caused by other factors such as birth-related or other physical trauma, infection, poisoning (e.g., lead poisoning) or reaction to pharmaceutical drugs, particularly neuroleptics, or stress. Treatment must be highly customized to the needs of the individual and may include oral medications, chemodenervation botulinum neurotoxin injections, physical therapy, or other supportive therapies, and surgical procedures such as deep brain stimulation. Classification There are multiple types of dystonia, and many diseases and conditions may cause dystonia. Dystonia is classified by: Clinical characteristics such as age of onset, body distribution, nature of the symptoms, and associated features such as additional...

The London Conference of 1912–1913, also known as the London Peace Conference or the Conference of the Ambassadors, was an international summit of the six Great Powers of that time (Austria-Hungary, France, Great Britain, Germany, Italy, and Russia) convened in December 1912 due to the successes of the Balkan League armies against the Ottoman Empire in the First Balkan War. In particular, the conference intended to arbitrate between the warring powers as to territorial acquisitions, and also to determine the future of Albania, whose independence was proclaimed during the conflict. History An armistice to end the First Balkan War had been signed on 3 December 1912. The London Peace Conference was attended by delegates from the Balkan allies (including Greece) who had not signed the previous armistice, as well as the Ottoman Empire. The Conference started in September 1912 at the St James's Palace under the chairmanship of Sir Edward Grey. Further sessions of the conference began on 16 December 1912, but ended on 23 January 1913, when the 1913 Ottoman coup d'état (also known as the Raid on the Sublime Porte) took...