In the eighties, software was a big challenge for me. In the early nineties as well, as I had to master multiprocessor systems available for the "masses" -- Intel and RISC machines instead of big Mainframes, to support Internet transaction systems. Nowadays, big challenges are elsewhere, that's why bright minds in the US are looking elsewhere. Software is just another tool, something you can outsource to occupy your bright mind with real challenges. It's boring to solve a problem a lot of people can solve. In US, there are bigger challenges to tackle at universities -- a rich, challenging environment. In poorer environments, bright people have less choices. US people are not less smart than they were in the eighties and nineties -- their interests changed, that's all. For the record, I'm Brazilian.

I beg to differ. It's 99% genetically compatible. 1% is mitochondrial DNA, which can still prompt an immune response rejecting a transplant. Unless the donor oocyte has the same mitochondria as the recipient -- like a mother, sister or maternal grandma's oocyte.

Sheeps and rabbits "convert more eggs to maturity" in each cycle than humans. Better now? When I had the idea of xenocloning I had just read an article saying that egg availability was one of the main barriers to human cloning. She-rabbits are also "born with all the eggs she'll ever have in her ovaries". I think that's true of all female mammals. Maybe the eggs must be mature (complete meiosis I and II and segregation of polar bodies) to be used in cloning. I don't know. Do you know?

You mean rabbits like carrots because of the genes in their mitochondria? Nothing would be left of their chromosomes. Maybe there's more to our preferences than our chromosomes. Good opportunity to know! I mean, clone chimps that would be eager for carrots. Cloning a human with such a compulsion would be unethical!

The problem with human cloning is women produce too few eggs - just one a month. There's one thing that isn't cloned from the original cell: mitochondria. The clone gets them from the egg, not from the original donor. So, why not use rabbit eggs? After a few cell divisions, all proteins would have been replaced by human proteins anyway. All but those in the mitochondria. I wonder what would happen to the organism? We can try it first with monkeys and rabbits to see whether it works or not. I had this idea soon after dolly, but felt I should keep my mouth shut. It seems the Chinese tried something like that some years later, but I don't know the results. Anyone here knows?

Life on Earth is made of strings. The beads are amino acids, nucleic acids. Why acids? Is there a thermodynamic reason this specific organization is the most likely to become alive? Or it's just Earth's environment 3 billion years ago, the specific context that determined amino acids and nucleic acids as the building blocks? A local set of constraints determines the most likely solution. How many different sets of constraints are there in the Universe? How many different solutions they determine?

Now convince criminals that your disembodied fingers won't work. There will always be skeptics. Don't worry, your missing fingers won't do the job for them.

I agree! No robots in the battlefield! I also propose that all battles from now on be fought by avatars in a game. Humans should be prohibited to engage in real battles, where they act as merciless robots, "just following orders", even "illegal" ones. A new Geneva convention should be summoned immediately to enforce these new rules of engagement!

I updated my iPhone 4 to iOS 6.1 yesterday. I live in Sao Paulo. Today I went to my parent's in Sao Bernardo (just 20 miles away) and tried to access 3G. I found out neither 3G nor my phone service were working. I turned off / restarted my iPhone, the problem continued. I thought it was a problem with the carrier (Vivo), but my brother-in-law laughed at me showing his Android phone working just fine with the same carrier. Back home, my iPhone started working again.This may be evidence that there is really a problem with iOS 6.1. I don't like to jump to conclusions, but it quacks like a duck...

40% compliance rate for washing hands in hospitals? In USA? I knew that to be a problem in Brazil, where I live, but I thought you Americans were more civilized. I must conclude this is a human problem, so it must be dealt with by machines. I propose the installation of access control to patients in all hospitals. Instead of badges, passwords, magnetic stripe cards, transponder (RFID, NFC) tokens or biometric authentication, just install a washbasin with detection equipment (computer vision, video recording). Ideally, the door would open only after the hand washing was properly detected. Just video recording could be enough, even if it were fake. "Somebody may be watching or will know that I broke the protocol" is a good incentive. An emergency button could allow immediate entrance, but a photograph would be taken and a report required to justify the breach. Wash your hands or do paperwork. I would wash my hands. That's only human. Expensive? How many lives would be saved?