Bitcoin – Wikipedia

Da Wikipedia, l'enciclopedia libera.

Bitcoin (simbolo: ; codice: BTC o XBT) una moneta elettronica creata nel 2009 da un anonimo conosciuto con lo pseudonimo di Satoshi Nakamoto, implementando un'idea dello stesso autore presentata su Internet a fine 2008. Convenzionalmente, il termine Bitcoin maiuscolo si riferisce alla tecnologia ed alla rete mentre il minuscolo bitcoin si riferisce alla valuta in s.[2]

A differenza della maggior parte delle valute tradizionali, Bitcoin non fa uso di un ente centrale: esso utilizza un database distribuito tra i nodi della rete che tengono traccia delle transazioni, e sfrutta la crittografia per gestire gli aspetti funzionali come la generazione di nuova moneta e l'attribuzione di propriet dei bitcoin.

La rete Bitcoin consente il possesso ed il trasferimento anonimo delle monete; i dati necessari ad utilizzare i propri bitcoin possono essere salvati su uno o pi personal computer sotto forma di "portafoglio" digitale, o mantenuti presso terze parti che svolgono funzioni simili ad una banca. In ogni caso, i bitcoin possono essere trasferiti attraverso Internet verso chiunque disponga di un "indirizzo bitcoin". La struttura peer-to-peer della rete Bitcoin e la mancanza di un ente centrale rende impossibile per qualunque autorit, governativa o meno, di bloccare la rete, sequestrare bitcoin ai legittimi possessori o di svalutarla creando nuova moneta.

Bitcoin una delle prime implementazioni di un concetto definito criptovaluta qui, descritto per la prima volta nel 1998 da Wei Dai su una mailing list[3].

Il controvalore totale dell'economia Bitcoin, calcolato a dicembre 2012 era di circa 140 milioni di dollari statunitensi[4], in aprile 2013 1,4 miliardi di dollari statunitensi[5], nel novembre 2013, con un cambio 1 bitcoin = 540 USD, il controvalore sale ancora a pi di 6 miliardi di dollari statunitensi[6].

L'economia basata sui bitcoin ancora molto piccola, se paragonata ad economie stabilite da lungo tempo, ed il software ancora in uno stato di beta release, tuttavia sono gi commercializzati in bitcoin merci e servizi reali quali, ad esempio, automobili usate o contratti di sviluppo software. I bitcoin vengono accettati sia per servizi online sia per beni tangibili[7].

Sono moltissimi ormai gli enti, le organizzazioni e le associazioni che accettano donazioni in bitcoin; tra i tanti si possono citare la Electronic Frontier Foundation[8], The Pirate Bay[9], Free Software Foundation[10] e anche Wikimedia Foundation[11].

possibile inoltre acquistare da altri grandi siti come Amazon o eBay attraverso alcuni intermediari. Dal novembre 2013 l'Universit di Nicosia, a Cipro, accetta il bitcoin come mezzo di pagamento della tasse universitarie.[12]. Alcuni commercianti, utilizzando appositi siti di cambio, permettono di cambiare bitcoin in diverse valute, ivi compresi dollari statunitensi, euro, rubli russi e yen giapponesi[13].

Chiunque pu controllare la catena dei blocchi (detta Blockchain) ed osservare le transazioni in tempo reale. Diversi servizi sono gi disponibili per facilitare queste operazioni.[14][15]

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Bitcoin - Wikipedia

Bitcoin – Wikipedia, la enciclopedia libre

Bitcoin, tambin Bitcin[3] (signo: ; abr.: BTC, XBT[4] ) es una criptodivisa descentralizada concebida en 2009 por Satoshi Nakamoto. El trmino se aplica tambin al protocolo y a la red P2P que lo sustenta.

Las transacciones en Bitcoin se realizan de forma directa, sin la necesidad de un intermediario. Al contrario de la mayora de las monedas, Bitcoin no est respaldado por ningn gobierno ni depende de la confianza en ningn emisor central,[5] sino que utiliza un sistema de prueba de trabajo para impedir el doble gasto y alcanzar el consenso entre todos los nodos que integran la red.[6]

Bitcoin es un proyecto relativamente nuevo que se encuentra en evolucin. Por esta razn, sus desarrolladores recomiendan ser cautos y tratarlo como software experimental.[7]

Desde la dcada de 1970, la utilizacin de firmas digitales basadas en criptografa de clave pblica ha proporcionado un fuerte control de propiedad.[8][Nota 1] Sobre la base de la criptografa de clave pblica, en 1998 Wei Dai describe b-Money,[9] una solucin descentralizada al problema de pagos electrnicos. Posteriormente, Nick Szabo y Hal Finney extienden y complementan el trabajo de Wei Dai.

En 2008, Satoshi Nakamoto publica un artculo en la lista de criptografa de metzdowd.com donde describe el protocolo Bitcoin.[8][10][11]

El 3 de enero de 2009 la red P2P de Bitcoin entra en funcionamiento con la publicacin del primer cliente, de cdigo abierto, y la creacin de los primeros bitcoines. Hasta la invencin de bitcoin era obligado que todos los pagos en el comercio electrnico se canalizaran a travs de entidades centralizadas de confianza,[12] generalmente bancos y otras empresas financieras, que gestionaban el seguimiento de todas las transacciones.

Satoshi Nakamoto es el seudnimo de la persona o el grupo de personas que disearon el protocolo Bitcoin en 2008 y que crearon la red en 2009. En una conferencia de criptgrafos se apuntaron los nombres de Michael Clear y Vili Lehdonvirt, pero ambos rechazaron ser Nakamoto.[13] En abril de 2011, Nakamoto anunci su desvinculacin del proyecto para dedicarse a otras labores.[13]

Aunque existen monedas[14] y billetes fabricados por particulares y empresas, normalmente para poder comerciar con bitcoines se utilizan programas cliente,[Nota 2] que pueden ser aplicaciones nativas o aplicaciones web.

Las aplicaciones nativas[15][16] se instalan o se ejecutan directamente en ordenadores o en dispositivos mviles.[Nota 3] Tambin pueden ejecutarse automticamente cuando el usuario clica en un navegador web sobre un enlace que cumple con el formato del URI scheme de bitcoin segn la especificacin registrada en IANA.[17]

Bitcoin Core es el nico programa que implementa totalmente el protocolo, protegiendo la red, y se considera la referencia en la que se apoyan el resto de clientes existentes. Bitcoin Core necesita descargar completamente la cadena de bloques y almacenarla localmente, lo que puede llegar a tardar varios das. Su uso solo se recomienda para usuarios avanzados que deseen aportar a la estabilidad de la red.

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Bitcoin - Wikipedia, la enciclopedia libre

MASL Weekly – Week 16

February 13, 2015 - Major Arena Soccer League (MASL) Comets Remain Unscathed, but Blast Finally Falter on the Road

2/11/15 - The Missouri Comets won two more games to extend their run to 18-0. Their 10-5 win in St. Louis Saturday, followed by an 11-4 rout of the Wichita B-52s Sunday were their 22nd and 23rd consecutive regular season wins going back to last season. Their last non-playoff loss was February 9, 2014 against the Baltimore Blast.

The Blast's own impressive season-opening streak of 13 wins ended abruptly when Ivan Simental converted a 2-0 break early in overtime to give the Las Vegas Legends a shocking 5-4 win. Before their first loss of the season could sink in, Baltimore had to travel to San Diego, where they suffered a 7-2 loss in one of the most anticipated games of the season. The Baltimore-San Diego rivalry which dates back to the 1982-83 season, has now officially been rekindled.

Kraig Chiles led the Sockers to victory with three goals and an assist and took the league lead with 42 goals, but he lost his league points record. Leo Gibson's five points Sunday gave him 73 on the season, eclipsing Chiles's record of 72 set during the 2012/13 season.

The Sockers, who hold the league record with 32 consecutive home regular season wins, have now won 13 straight at the Valley View Casino Center.

MASL Team of the Week

GK - Chris Toth, San Diego Sockers

Toth recorded 12 saves, a handful spectacular, as the Sockers beat the Baltimore Blast 7-2 in front of 6,274 fans on Saturday night. Toth's biggest saves came when the game was tied 1-1, stopping a point-blank volley in the final two minutes of the second quarter, and then a back post sitter in the opening seconds of the third quarter. Toth is 10-3 in net this season with a 4.82 GAA and .722 save percentage.

GK - Zeke Sanchez, Las Vegas Legends

Sanchez recorded 20 saves and allowed only 4 goals on Friday night leading the Legends to a victory over the then-undefeated Baltimore Blast. He leads the league in games played (17) minutes (1034) and number of saves (277).

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MASL Weekly - Week 16

Beautiful island in the world, travel to to beautiful around the world – Video


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Fox World Travel Hosts European River Cruise Travel Show

(PRWEB) February 13, 2015

Fox World Travel is excited to announce their European River Cruise Travel Show. The show is being presented on Wednesday, February 25th in two locations. The first showing will be held at Brookfield Suites at 1:30pm. The second showing will be held at the Oconomowoc Lake Club at 6:30pm. The one hour presentations will be held by Fox World Travels knowledgeable representatives and attendees will be provided with brochures, flyers, refreshments, door prizes and more. Admission is free, but space is limited so those interested in attending are asked to RSVP online.

Fox World Travel European River Cruises include added amenities and features, special value pricing, customized itineraries, and often the comfort and convenience of an experienced tour manager to ensure a worry-free experience for travelers. At this presentation, attendees are able to learn about Fox World Travel's exclusive Select Group Vacations, featuring those added amenities and special values that can't be found anywhere else. According to Avalons website, European River Cruises are among their most popular itineraries. For more information visit Fox World Travel online at gofox.com.

About Fox World Travel, Inc.:

Fox World Travel was founded in 1960 and is ranked as top travel agency in the United States, according to the Business Travel Survey in Business Travel News. Fox World Travel owns and operates 11 retail travel locations throughout Wisconsin as well as a full service corporate travel division and Premier Meetings and Incentives in Oshkosh and Fox World Travel School. Fox World Travel is the largest vacation travel agency in Wisconsin. Fox World Travels corporate travel division is a leading provider of travel management solutions, serving travelers as they navigate the globe while guiding organizations toward successful policies, compliance and financial advantages in their domestic and global travel programs. Visit Fox World Travel online at http://www.GoFox.com.

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Fox World Travel Hosts European River Cruise Travel Show

FAQ Part 1: MEsenchymal Stem cell therapy for CAnadian MS patients (MESCAMS) – Video


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Stem Cell Therapy for Erectile Dysfunction – Alvarado Hospital – Video


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Grace Centurys Portfolio Project Board Member Asked to Serve on Bahamian Pre-Clearance Stem Cell Ethics Committee

Ras Al Khaimah, UAE (PRWEB) February 12, 2015

Private equity and international research consultancy, Grace Centurys portfolio company, Provia Laboratories, LLC, has announced, just days after the provisional approval of the firms new entrance into the Commonwealth, that Dr. James A. Manganello has been invited to serve on a newly formed pre-clearance team for future entities applying for activity in the Caribbean nation.

The purpose of this team, led by Dr. Desiree Cox, Rhodes Scholar, MD, Ph.D., MPhil, is to provide quality control of the stem cell research and stem cell therapy applications submitted to the Bahamian National Stem Cell Ethics Committee.

"This further demonstrates Provias leadership in this field. Provia has advised pharmaceutical/biotech companies and consulted on multiple initiatives within the National Institutes of Health (NIH) in the field of biobanking for many years now. The team has established itself as a group of thought leaders in the field of bio-banking and stem cell science, Scott Wolf, CEO of Grace Century, commented.

The commonwealth continues to fortify its vision for establishing the nation as a true global force in health care innovations and in the future of the stem cell industry, Wolf added.

I am truly honored to be invited to participate on such an important team, Dr. Manganello said. The Bahamian government, with the help of local businesses, the medical community, and local investors, are trying to attract the best technologies from around the world, and to establish itself as a destination for innovative healthcare. I am excited to do my part to help ensure the highest quality and standards are adhered to.

About Grace Century Grace Century FZ LLC is an International research and private equity consultancy located in Ras Al Khaimah, (north of Dubai) in the United Arab Emirates (UAE). Grace Century specializes in game-changing life science and health related private equity projects.

About Provia Laboratories, LLC Headquartered in Littleton, MA, Provia Laboratories, LLC is a healthcare services company specializing in high-quality bio-banking (the collection, transport, processing and cryogenic storage of biological specimens). Provia Labs offers the Proviasette product range for use in bio-banking environments to improve sample logistics, security and quality. The company manages and promotes its own bio-bank for a dental stem cell banking service, Store-A-Tooth, which gives families the option to store stem cells to protect their childrens future health and take advantage of advances in stem cell therapies. Provia advises industrial, academic and governmental clients on matters related to the preservation of biological specimens for research and clinical use. Provia Labs is a member of ISBER, the International Society for Biological and Environmental Repositories, as well as ESBB, the European, Middle Eastern & African Society for Bio-preservation & Bio-banking. For further information about Provia Labs products and services, call +1 (781) 652-4815 or visit http://www.store-a-tooth.com.

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Grace Centurys Portfolio Project Board Member Asked to Serve on Bahamian Pre-Clearance Stem Cell Ethics Committee

A VACCINE TO DESTORY SPIRITUALITY! Pentagon Develops Way to Eliminate Faith, Human Soul? Illuminati – Video


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A VACCINE TO DESTORY SPIRITUALITY! Pentagon Develops Way to Eliminate Faith, Human Soul? Illuminati - Video

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