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Submission + - Two mutations triggered an evolutionary leap 500 million years ago (uchospitals.edu)

Taco Cowboy writes: "Changes in just two letters of the genetic code in our deep evolutionary past caused a massive shift in the function of one protein and set in motion the evolution of our present-day hormonal and reproductive systems," said Joe Thornton, PhD, professor of human genetics and ecology & evolution at the University of Chicago

In a feat of "molecular time travel" the researchers resurrected and analyzed the functions of the ancestors of genes that play key roles in modern human reproduction, development, immunity and cancer. By re-creating the same DNA changes that occurred during those genes' ancient history, the team showed that two mutations set the stage for hormones like estrogen, testosterone and cortisol to take on their crucial present-day roles

"If those two mutations had not happened, our bodies today would have to use different mechanisms to regulate pregnancy, libido, the response to stress, kidney function, inflammation, and the development of male and female characteristics at puberty," Thornton said

Understanding how the genetic code of a protein determines its functions would allow biochemists to better design drugs and predict the effects of mutations on disease. Thornton said the discovery shows how evolutionary analysis of proteins' histories can advance this goal, Before the group's work, it was not previously known how the various steroid receptors in modern species distinguish estrogens from other hormones

They found that just two changes in the ancient receptor's gene sequence caused a 70,000-fold shift in preference away from estrogens toward other steroid hormones. The researchers also used biophysical techniques to identify the precise atomic-level mechanisms by which the mutations affected the protein's functions. Although only a few atoms in the protein were changed, this radically rewired the network of interactions between the receptor and the hormone, leading to a massive change in function


Submission + - Satellites providing Internet to the "under-connected" (phys.org)

Taco Cowboy writes: On this Tuesday, a Russian Soyuz rocket will shoot the first 4 of 12 satellites in a new constellation that are designed to provide affordable, high-speed Internet to people in nearly 180 "under-connected" countries

The orbiters, part of a project dubbed O3b for the "other 3 billion" people with restricted Internet access, were built by the Franco-Italian company Thales Alenia Space, will orbit at 8,062 km and will weigh only 650 kilogrammes (1,400 pounds) each

There are already geostationary satellites providing this type of services, but at a prohibitive cost for many end-users. Existing satellites generally obit at an altitude of some 36,000 kilometres (22,000 miles) above Earth, weigh in at a hefty four to six tonnes each, and take much longer to bounce a signal back to Earth—about 500 milliseconds to be exact, according to an O3b document. "It is such a long delay that people speaking over a satellite link will shorten conversations, interactive web has an extremely poor experience and many web-based software programmes just won't function," as stated in the said document

Crucially, they will communicate with Earth four times faster, said the company, and six would be enough to assure permanent coverage. "O3b's prices will be 30 — 50 percent less than traditional satellite services," said the document

Launch company Arianespace, which will put the satellites in orbit, said the O3b constellation will combine "the global reach of satellite coverage with the speed of a fiber-optic network"

Project investors include Internet giant Google, cable company Liberty Global, satellite operator SES, HSBC bank and the Development Bank of Southern Africa

The first four satellites were due to be boosted into space on Monday but the launch was postponed by a day due to unfavourable weather conditions

The next four satellites will be launched within weeks, according to Arianespace, and a final four "backup" orbiters early next year

Comment Negetive interest makes cash less interesting... (Score 1) 446

If you owe money in this economy, paying it back early with liquid cash is a better value than holding it. Why have cash when it can't even keep pace with inflation? Savers are punished, and so are the taxpayers when this hot potato comes back to us before it has cooled. Who needs cash when its not worth the paper its printed on? Tesla is making a smart hedge on the current economic situation, which shows real sophistication in corporate automobile technology and salesmanship....

Comment Re:50 years ago... (Score 1) 184

"We now face the danger, which in the past has been the most destructive to the humans: Success, plenty, comfort and ever-increasing leisure. No dynamic people has ever survived these dangers."

I quite agree with you and Mr. Steinbeck, as I sit here in Steinbeck Country - generally unemployed, unsuccessful, with plenty of ever increasing leisure and discomfort; I realize nothing ever survives. Steinbeck has surpassed all danger.

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