The Mexican Border Service Medal was a United States military award, established by an act of the United States Congress on July 9, 1918. The medal was awarded for service between May 9, 1916 and March 24, 1917, or with the Mexican Border Patrol between January 1, 1916 to April 6, 1917; the medal recognizes those military service members who were assigned to the U. S.-Mexico border at the period of time when the United States was on the verge of all-out war with Mexico. The United States was engaged in the Pancho Villa Expedition, a military operation conducted by the United States Army against the paramilitary forces of Mexican revolutionary Francisco "Pancho" Villa from March 14, 1916, to February 7, 1917, during the Mexican Revolution 1910–1920; the U. S.-Mexico border was thought to be a potential location for a German-funded invasion by Mexico. Border service went into effect when this possible threat was exposed with the British interception of the Zimmerman Telegram, which discussed Germany's proposal that Mexico join in an alliance with Germany if the U.

S. were to enter the war. To be awarded the Mexican Border Service Medal, a service member must have served with the United States Army, along the Mexican border, or must have been assigned as a Regular or National Guard member to the Mexican Border Patrol; those who had received the Mexican Service Medal were not eligible for the Mexican Border Service Medal. The United States National Guard was sent to guard the American side of the border as regular Army personnel were being depleted by the efforts in Mexico; the Mexican Border Service Medal held dual status as both a U. S. Federal and National Guard medal; the first recipient was Major General Charles M. Clement, in recognition of his status as the longest-tenured National Guard officer eligible for the award at the time it was authorized. Congress created a similar award to present to members of the Texas National Guard who served on the border from December 8, 1917 to November 11, 1918, known as the Texas Cavalry Medal; these guardsmen deployed to the border to free up regular Army units for service during World War I.

Awards and decorations of the United States military

Primecoin is a cryptocurrency that implements a proof-of-work system that searches for chains of prime numbers. Launched on July 7, 2013 by anonymous hacker and peercoin founder Sunny King, Primecoin was the first cryptocurrency to have a proof-of-work system with a practical use. Earlier cryptocurrencies, such as Bitcoin, were mined using algorithms that solved arbitrary mathematical problems, the results of which had no value or use outside of mining the cryptocurrency itself. Primecoin's algorithm, computed chains of prime numbers, the results of which were published on its blockchain's public ledger, available for use by scientists and anyone else. Use of a proof-of-work system to calculate chains of prime numbers was an innovation that produced useful results while meeting the criteria for a proof-of-work system: it involved a calculation, difficult to perform but easy to verify, the difficulty was adjustable. Shortly after its launch, some trade journals reported that the rush of over 18,000 new users seeking to mine Primecoin overwhelmed providers of dedicated servers.

Unlike Bitcoin, Primecoin targets a block generation period of one minute rather than every ten minutes, changes difficulty every block rather than every 2016 blocks, has a dynamic block reward, a function of the difficulty. Primecoin transactions are confirmed 8–10 times as fast as Bitcoin transactions. Orrell, David; the Evolution of Money. New York: Columbia University Press. Pp. 200–201. ISBN 978-0-231-17372-8. Retrieved 2018-11-13. Antonopoulos, Andreas M.. Mastering Bitcoin: Unlocking Digital Cryptocurrencies. Sebastopol, California: O'Reilly Media. ISBN 978-1-4919-2198-2. Retrieved 2018-11-13. Fanning, Kurt. "Blockchain and Its Coming Impact on Financial Services". Journal of Corporate Accounting & Finance. 27: 54–55. Doi:10.1002/jcaf.22179. Official website