How does Bitcoin work?

Bitcoin, the world’s “first decentralised digital currency”, was launched in 2009 by a mysterious person (or persons) known only by the pseudonym Satoshi Nakamoto. It has been in the news this week as the value of an individual Bitcoin, which was just $20 at the beginning of February, hit record highs above $250, before falling abruptly to below $150 on April 11th. What exactly is Bitcoin, and how does it work?

Unlike traditional currencies, which are issued by central banks, Bitcoin has no central monetary authority. Instead it is underpinned by a peer-to-peer computer network made up of its users’ machines, akin to the networks that underpin BitTorrent, a file-sharing system, and Skype, an audio, video and chat service. Bitcoins are mathematically generated as the computers in this network execute difficult number-crunching tasks, a procedure known as Bitcoin “mining”. The mathematics of the Bitcoin system were set up so that it becomes progressively more difficult to “mine” Bitcoins over time, and the total number that can ever be mined is limited to around 21m. There is therefore no way for a central bank to issue a flood of new Bitcoins and devalue those already in circulation.

The entire network is used to monitor and verify both the creation of new Bitcoins through mining, and the transfer of Bitcoins between users. A log is collectively maintained of all transactions, with every new transaction broadcast across the Bitcoin network. Participating machines communicate to create and agree on updates to the official log. This process, which is computationally intensive, is in fact the process used to mine Bitcoins: roughly every 10 minutes, a user whose updates to the log have been approved by the network is awarded a fixed number (currently 25) of new Bitcoins. This has prompted Bitcoin fans to build powerful computers, or even to hijack other people’s computers, for use in Bitcoin mining.

Bitcoins (or fractions of Bitcoins known as satoshis) can be bought and sold in return for traditional currency on several exchanges, and can also be directly transferred across the internet from one user to another using appropriate software. This makes Bitcoin a potentially attractive currency in which to settle international transactions, without messing around with bank charges or exchange rates. Some internet services (such as web hosting and online gambling) can be paid for using Bitcoin. The complexity and opacity of the system means it also appeals to those with more nefarious purposes in mind, such as money laundering or paying for illegal drugs. But most people will be reluctant to adopt Bitcoin while the software required to use it remains so complex, and the value of an individual Bitcoin is so volatile. Just as BitTorrent was not the first file-sharing service and Skype was not the first voice-over-internet service, it may be that Bitcoin will be a pioneer in the field of virtual currencies, but will be overshadowed by an easier-to-use rival.

{ The Economist }

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The macaroni’s soggy, the peas are mushed and the chicken tastes like wood

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What do you do if you drop your sandwich on the floor? Pick it up within five seconds and just continue eating? […]

American researchers wanted to test  how long food has to be on the floor before it becomes contaminated. They dropped sausages and bread onto different surfaces, such as carpet, wood and tiles, and examined  the transfer of Salmonella bacteria.

They found that of all the bacteria that contaminated the food, 99 percent of them  had transferred already in the first five seconds. The time it took them was influenced by the kind of surface the bacteria were on, yet only a little. Bacteria on carpet took more time to get onto the sausages than those on wood or tile.

We all have enough strength to endure the misfortunes of others

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Why do we sigh?

Does it help regulate my breathing when I’m stressed? Is it a subconscious action I do to express to those around me that I’m anxious or upset? Perhaps a mental reset button, so to speak?

In fact, it may be a combination of all three.

In a series of studies, Teigen and colleagues at University of Oslo explored the context in which people sigh—when are people doing it, and how is it perceived by others?

photo { Mario Torres }

Flip of a single molecular switch makes an old brain young

The flip of a single molecular switch helps create the mature neuronal connections that allow the brain to bridge the gap between adolescent impressionability and adult stability. Now Yale School of Medicine researchers have reversed the process, recreating a youthful brain that facilitated both learning and healing in the adult mouse.

Scientists have long known that the young and old brains are very different. Adolescent brains are more malleable or plastic, which allows them to learn languages more quickly than adults and speeds recovery from brain injuries. The comparative rigidity of the adult brain results in part from the function of a single gene that slows the rapid change in synaptic connections between neurons.

By monitoring the synapses in living mice over weeks and months, Yale researchers have identified the key genetic switch for brain maturation a study released March 6 in the journal Neuron. The Nogo Receptor 1 gene is required to suppress high levels of plasticity in the adolescent brain and create the relatively quiescent levels of plasticity in adulthood. In mice without this gene, juvenile levels of brain plasticity persist throughout adulthood. When researchers blocked the function of this gene in old mice, they reset the old brain to adolescent levels of plasticity.

{ Eureka Alert | Continue Reading }

Dogshit Orgasm.


From Cat Piss to Alaskan Thunderfuck, marijuana strains have strange names; here’s why we’re in for more soon

Golden Goat is a strain of marijuana distinguished by a citrus scent and a potent but mellow buzz. “The person who originally created that strain, I knew him personally,” explains Garrett Pearson of Natural Remedies Medical Marijuana Dispensary in Colorado. “There was a recycling plant out in Kansas where the strain is originally from. When the sun hit those empty bottles and the scent of soda and beer mingled, it smelled a certain way, and that’s just what the strain smells like. So he named it Golden Goat after the Golden Goat recycling factory.”

Greg Williams, better known as Marijuana Man, told me the story behind another strain. Williams used to sell seeds by mail order, “There was a strain in our catalogue called A-Frame. We always wondered why it was called A-Frame,” he said, in exactly the sort of leisurely drawl you might expect from someone known as Marijuana Man. “We thought maybe it was because the shape of the plant was like an A-shape but it turns out, the seeds originally came from a guy who lived in an A-frame.”

OG Kush, Big Afghan Skunk, AK47, Alien God, Fraggle Rock, Smelly Guy, Blueberry Yum Yum. There’s one named Snoop Dogg too. It’s potent and cerebral. According to online reviews, your brain will feel like it’s hovering over your body.

Linnaean biological classifications divide the genus Cannabis into three species: indicasativa, and ruderalis. The strain named for DO-double-G is one of many indicas, distinguished from the sativas by its drowsy, fullbody effects. Sativas provide a more energetic high. To speak in reductive binaries, indica is nighttime while sativa is daytime. No one really cares about ruderalis because it has a negligible THC count.

{ The New Inquiry | Continue Reading }