Synthetic cells get together to make electronics

A network of artificial cells that work together to act as an AC/DC converter has been built. Demonstrating that synthetic cells can team up to achieve such feats is a step towards building synthetic tissues to interface biology with electronics, says the team of chemists behind the work.

Synthetic biologists have show they can reprogram living cells to make them produce drug compounds, and are even working towards building cells from scratch to create artificial life.

But that work focuses on only individual cells, says Hagan Bayley at the University of Oxford. He’s more interested in making artificial tissue in which individual synthetic cells work together.

Bayley’s group, working with colleagues at the University of Massachusetts in Amherst, has made a step towards that goal by connecting together multiple artificial “protocells” so that they share electrical signals.

Source: New Scientist.

Israeli military robot snake

Geoengineering: More Political and Moral Than Scientific?

The prospect of geoengineering continous to spark debate among scientists, environmentalists and politicians. Recently NPR carried an article on the topic:

Engineering our climate to stop global warming may seem like science fiction, but at a recent National Academy of Sciences meeting, scientists discussed some potential geoengineering experiments in earnest.

Climate researcher Ken Caldeira was skeptical when he first heard about the idea of shading the Earth a decade ago in a talk by nuclear weapons scientist Lowell Wood.

“He basically said, ‘We don’t have to bother with emissions reduction. We can just throw aerosols — little dust particles — into the stratosphere, and that’ll cool the earth.’ And I thought, ‘Oh, that’ll never work,’ ” Caldeira said.

But when Caldeira sat down to study this, he was surprised to discover that, yes, it would work, and for the very same reasons that big volcanoes cool the Earth when they erupt. Fine particles in the stratosphere reflect sunlight back into space. And doing it would be cheap, to boot.

Tim Harper (Cientifica), a long time commentator on ethics and nanotechnology recently blogged about geoengineering:

I recently suggested that we need a New Green Agenda, one based on solving problems not just mitigating them, and drawing on everything that science and technology can offer to create a more sustainable future. Greenpeace, rather surprisingly from a scientific viewpoint but obviously from a political one refused to countenance any funding for geoengineering or any trials, even small scale local ones and put up the rather weak argument that it would take funding away from other areas of environmental science.  One of the attractions of geoengineering is that it is cheap and uses mainly existing technologies, so a few tens of millions of dollars spent evaluating options is hardly going to handicap the the rest of the research community. I tend to agree with David Keith and growing number of others that if we are serious about climate change then we should be trying to do something about it rather than delaying research.

Probing further it seems that geoengineering horrifies Greenpeace and other NGOs precisely because it does offer a solution. The real reason Greenpeace dislikes ideas such as this is that it may offer politicians an excuse to stop buying into the sustainable/renewable argument which they have been promoting for thirty years, or to put it their terms “may reduce the political and social impetus to reduce carbon emissions.”

The many vested interests in climate politics may feel threatened by an actual solution to the problem of global warming. The conspiracy crowd feel threatened by the possible harmful effects on humans by experiments in tweaking the atmosphere.

A Thermodynamic Limit on Brain Size

If our brains have to be cooled like computer chips, is there a limit on how big they can be?

In recent years, chip makers have conlcuded that the race to produce ever faster circuits is a fool’s game. As the clock speed increases, the amount of energy lost as heat becomes too large to dissipate efficiently and in any case, the waste is unjustifiable.

That raises some interesting questions about the human brain, says Jan Karbowski at the Sloan-Swartz Center for Theoretical Neurobiology at the California Institute of Technology. Karbowski points out that the problem of heat transfer could be a serious factor shaping brain evolution and so has embarked on a program to determine the relationship between brain temperature, its size, cerebral power generated and neural activity.

The question on Karbowski’s mind is whether there is any thermodynamic limit on brain size. And if so, does 5 kg, which Karbowski says is the mass of the largest mammalian brain, approach that limit?

Source: Arxiv blog.

Also see “Why Worry About This Sci-Fi Stuff Now? Mindfiles, Mindware and Mindclones” on IEET.

Quantum tunneling with nanowires

Nanowires

Quantum tunneling is the capability of a particle to inhabit regions of space that would normally be off-limits according to classical mechanics. This research observes a process called a quantum phase slip, whereby packs of roughly 100,000 electrons tunnel together from higher electrical current states to lower ones. The energy locked in the motion of the electrons as they phase slip is dissipated as heat, causing the nanowires to switch from a superconducting state to a more highly resistive one.

Source: University of Illinois. The researchers hope this effect could be used for quantum computing.

Also read “New rotors could help develop nanoscale generators” about more breakthroughs in nanotechnology from Eurkalert.

Latest human cloning claims leave sour taste

It’s clone-mania again, for the second time in just a few weeks. This time, it’s fertility expert Panayiotis Zavos, founder of the private Zavos Organization in Lexington, Kentucky, claiming that he made 14 human cloned embryos and transferred 11 of them into the wombs of women.

None of the embryos survived this time (allegedly), but “the cloned child is coming”, Zavos told The Independent newspaper in the UK. “There is absolutely no way that it will not happen.”

Last month, we had the spectacle of Italian fertility expert Severino Antinori’s assertion that three clones already exist: two boys and a girl. He told Italy’s Oggi magazine that the children are now nine years old and living in eastern Europe.

But as usual, he provided no scientific proof to confirm that they were indeed clones. Nor did he submit any scientific data for publication. How on earth are we supposed to believe these claims?

Source: New Scientist.

Manning the barricades

Ill. “Blackouts and Cascading Failures of the Global Markets”,
Scientific American.

The credit crunch is dragging down the global economy and raising political tensions

Collapsing credit has plunged the world economy into the deepest recession in more than 70 years. What began as a property bubble in the US has spread rapidly as troubled banks have stopped lending and consumers and businesses have stopped spending. As demand in the US and Europe evaporates, once-thriving emerging markets are losing their best customers and biggest investors. An increasingly synchronised global economy will contract in 2009 for the first time since World War II.

Eighteen months after it began, this economic chain reaction—from banks to markets to consumers to companies—is entering a new phase. Economic pain, reflected in millions of lost jobs and destroyed savings, has entered the political realm, causing some governments to collapse and threatening others. The risk of political instability is leading to a wave of trade protectionism, which is rippling across the globe. It was just such a political response in the 1930s, exemplified by America’s infamous Smoot-Hawley tariffs, that deepened and prolonged the Great Depression.

Source: “Introduction: Banks, busts and batons”, The Economist Intelligence Unit. Download the entire report “Manning the barricades: Who’s at risk as deepening economic distress foments social unrest” (PDF).

Artificial human body parts

Exact replicas of a man’s thumb bones have been made for the first time
using a printer that uses natural materials for ink

EXACT replicas of a man’s thumb bones have been made for the first time using a 3D printer. The breakthrough paves the way for surgeons to replace damaged or diseased bones with identical copies built from the patients’ own cells.

“In theory, you could do any bone,” says Christian Weinand of the Insel Hospital in Berne, Switzerland, head of the team that copied his thumb bones. “Now I can put spares in my pocket if I want,” he says.

Weinand “grew” his replacement bones on the backs of laboratory mice, in the same way that Jay Vacanti of Massachusetts General Hospital famously grew a human ear from human cartilage cells back in 1997.

Source: “Thumbs up for 3D bone printer”, New Scientist.

The smooth cartilage that covers the ends of long bones provides a level of lubrication that artificial alternatives haven’t been able to rival – until now. Researchers say their lubricating layers of “molecular brushes” can outperform nature under the highest pressures encountered within joints, with potentially important implications for joint replacement surgery.

With every step we take, bones at the knee and hip rub against each other. That would quickly wear them away if it wasn’t for the protection afforded by the thick layer of smooth and slippery cartilage that covers their ends.

No amount of polishing can remove all of the small imperfections from the stainless steel used in artificial joints. Any raised areas that are left grind against each other and release debris particles that soften the bone, explains Jacob Klein at the Weizmann Institute of Science in Rehovot, Israel.

Like bone, artificial joints must be covered with a cartilage-like layer. However, while it’s possible to match cartilage’s slick properties at low pressure, at the high pressures found in joints synthetic alternatives “seize up”.

Source: “Artificial cartilage performs better than the real thing”, New Scientist.

Hacking the planet: The only climate solution left?

Click image to enlarge.

Geoengineering schemes range from the low-tech, such as planting trees, to sci-fi, such as placing mirrors in orbit between Earth and the sun. All would work either by diverting solar energy away from Earth or by sucking carbon dioxide out of the atmosphere to dampen the greenhouse effect (see diagram).

Previously, the idea of tweaking the climate in this way was anathema to most scientists. Apart from the technical challenges and environmental risks, many argued that endorsing the concept might scupper international negotiations for a post-Kyoto protocol to reduce global emissions. But it’s becoming clear that moves to cut global carbon emissions are too little and too late for us avoid the worst effects of climate change. “There is a worrying sense that negotiations won’t lead anywhere or lead to enough,” says Lenton. “We can’t change the world that fast,” says Peter Liss, who is scientific adviser to the UK parliamentary committee investigating geoengineering. Extraordinary measures may now be the only way of saving vulnerable ecosystems such as Arctic sea ice.

Source: New Scientist.

Quantum dance: Discovery led by Princeton researchers could revolutionize computing

Theorists have long predicted that atoms placed in certain configurations would trigger electrons to behave in odd “quantum” ways. The Princeton-led team has been searching for a material that would produce these conditions. In the Feb. 13 issue of Science, the team has reported it witnessed the exotic behavior in a carefully constructed crystal made of an antimony alloy laced with bismuth.

Surveying the structure on an atomic level with new techniques, the scientists have recorded swarms of electrons spinning in a synchronized quantum dance. The coordinated behavior observed involves a strange form of rotation. Unlike most objects, which return to their original “face” when revolved full circle or 360 degrees, the harmonized electrons need to be twisted two full turns or 720 degrees in order to go back to the same face at the surface of the material.

Source: Princeton University.