Post in evidenza

AI Revolution: Robot Operation System

Sophia, the first humanoid robot to receive citizenship of a country.   She was featured on the cover of Ella Brazil magazine and has a...

giovedì 19 gennaio 2012

Primi organismi complessi in 'provetta'

Ricostruita in laboratorio una tappa dell'evoluzione: il passaggio da organismi unicellulari a multicellulari. E il primo atto degli organismi complessi e' il suicidio programmato delle cellule: lo rileva uno studio sul lievito pubblicato su Pnas. Dati alla mano il passaggio avviene piu' rapidamente di quanto si immaginasse e nell'evoluzione della divisione del lavoro all'interno di gruppi di cellule la maggior parte delle cellule rimane vitale e si riproce, mentre una minoranza si suicidia.

Primi organismi complessi in 'provetta' 17 gennaio 2012

Artificial Testicles

Researchers in California are working to build an artificial testicle, a human "sperm-making biological machine," that can produce human sperm and allow otherwise infertile men to make babies.
According to My Health News Daily, Dr. Paul Turek, director of the Turek Clinic, a men's health medical practice in San Francisco, says that recent advances show that the idea of treating infertility in male animals by producing sperm using stem cells is feasible. While this has been done successfully in mice, it has not been done in humans.
Turek recently announced on his Turek on Men's Health site that he has received a government grant to develop a human "sperm-making biological machine." According to My Health News Daily, Turek and his colleague, Dr. Constance John, chief executive of MandalMed Inc., a biotech company in San Francisco, received a small research grant from the National Institute of Environmental Health Sciences.
Turek says the new "machine" will not be designed to resemble a testicle like non-sperm-producing prosthesis that are saline-filled implant for men who don't have testicles. Rather, the sperm producing machine will come as a cylindrical bag a few inches in length and will look "like a transparent, over-sized Tootsie Roll." Turek on Men's Health explains: "To be clear, this grant is not about creating a testicular implant for a man who is missing a real one. We did that a decade or so ago. This award is to develop a sperm making biological machine...We now have a couple of years to create human artificial sperm in a dish, or more formally, a 'bioreactor,' a fancy dish to be sure."
This is not the first time scientists will attempt to device artificial methods for growing sperm cells. But so far, attempts have failed because the sperm cells do not complete the necessary steps in spermatogenesis, that is, the biological process in which sperm cells are created. Spermatogenesis goes through 12 stages, but so far, attempts to take cells through the stages under artificial conditions end at the 9th or 10th stage, showing that the last stages require very precise conditions provided by the testicles in its natural state, specifically, the conditions in the the testicular structures in which the main stages of spermatogenesis occur, namely, the seminiferous tubules. According to Turek, he and his team are working to, "re-create the testicle in an artificial environment, with all of its components."
The researchers say that they will begin by growing cells, such as sertoli cells, that are involved in nurturing sperm cells during development in the seminiferous tubules. The researchers will then add embryonic stem cells, that is, cells that can be grown into any cell in the human body. The stem cells will have special genes directing spermatogenesis implanted in them to ensure that they develop into viable sperm precursor cells.
An alternative method, according to Turek, would be to use adult stem cells rather than embryonic stem cells. In this case, the cells could be taken from the human skin (the patient's) and the "clock turned back" so that the cells develop into sperm. But it is not certain whether this is feasible, Turek said.
According to the researchers, the artificial testicles will last only about 70 days, the approximate time it takes for one cycle of sperm production.
My Health News Daily reports Kyle Orwig, associate professor of obstetrics, gynecology and reproductive sciences at the University of Pittsburgh, said: "It's an ambitious project. But it would be fantastic if it happened. It would have an important impact on fundamental investigations of human sperm production as well as the fertility field...To my knowledge, no one has tried to create sperm in this specific manner before. The major challenge will be figuring out how to get the human stem cells to become sperm precursor cells. Several labs around the world are actively working on this problem with some reported successes."

Researchers to build artificial testicles for infertile men Jan 19, 2012

giovedì 12 gennaio 2012

Etica Artificiale

Un robot entra in un bar e ordina uno screwdriver (letteralmente: cacciavite). Pessima battuta, ma sarebbe stato peggio se fosse entrato nel bar dicendo "Mani in alto, questa e' una rapina!"

Queste le prime due righe (da me liberamente tradotte) di un articolo su un blog del New York Times: The Future of Moral Machines, by Colin Allen. Il giornalista accenna al concetto di Friendly AI, a dimostrazione che l'idea sta percolando al di fuori del ghetto singolaritario, e sostiene che lo sviluppo di un'etica artificiale (machine morality) e' fondamentale e che e' sara' possibile ottenerla solo riconciliando ingegneria elettronica e filosofia.

Intelligenza Artificiale: un articolo del New York Time sulla "etica artificiale" 12 gennaio 2012

IBM Brains Turn 12 Atoms Into World’s Smallest Storage Bit

IBM researchers have found a way to put a single bit of data on a 12-atom surface, creating the world’s smallest magnetic storage device.
It’s a breakthrough that’s not likely to make its way into hard drives or memory sticks for decades, but it gives us a hint at how much road lies ahead for magnetic storage devices.
Before now, physicists really didn’t know how small they could take magnetic storage before the laws of quantum mechanics would take over, making it impossible to reliably store data. String together 8 atoms, for example, and you simply can’t get a stable magnetic state, says Andreas Heinrich, the IBM researcher behind the discovery. “The system will just spontaneously hop from one of those states to another state in a timescale that is too fast for us to claim anything like a data storage [demonstration]. It might be switching 1,000 times per second.”
Another problem: how to keep neighboring bits of data from interfering with each other? Today’s hard drives store data in what’s known as a ferromagnetic structure. This is how a compass needle or a refrigerator magnet work: They have lots of atoms lumped together, all pointing in the same magnetic directions.
IBM’s 12-atom bit-keeper uses an antiferromagnetic structure, however, meaning that the atoms point in opposite directions. This keeps the atoms from interfering with each other, an important feature when you’re storing data just 12 atoms at a time. “In a ferromagnet all of these atoms add together to make a big spin and that big spin interacts with the neighboring big spin. And so you cannot control these independently anymore,” Heinrich says. “But in an antiferromagnet there is no big spin, and so you can put these guys very close together”
Heinrich did his work using a scanning tunneling microscope (STM), something that IBM researchers invented 30 years ago, which allows them to see and move around atoms.
12-atom storage devices would be much, much smaller than today’s disks. Heinrich’s friends at hard-drive maker Hitachi estimate that their storage drives require about 800,000 atoms per bit.
So what’s keeping the atom-scale flash drive from showing up at your local Best Buy? Well, first off, they operate at 1 degree kelvin. That’s about -458 Fahrenheit. Bump things up to room temperature and Heinrich thinks it would take about 150 atoms per bit.
And there’s an even bigger problem. Nobody has a clue how to build something this small outside of the lab. And certainly, nobody can do it cheaply, Heinrich says. “That is something that many people are working on, but nobody has solved it yet.”
Still, when Heinrich got his first glimpse at the 12 atoms holding a charge in his STM last spring, he was mesmerized. He sat at his Almaden lab for four hours straight, switching the tiny clump of atoms back and forth between magnetic states. “I was basically just blown away,” he says. “Every once in a while, even we who work with this kind of stuff on an almost daily basis get blown away that it is actually possible.”

IBM Brains Turn 12 Atoms Into World’s Smallest Storage Bit January 12, 2012

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