Cheerful or not

Big Data Needs a Big Theory to Go with It || Scientific American

To bring scientific rigor to the challenges of our time, we need to develop a deeper understanding of complexity itself.

What does this mean? Complexity comes into play when there are many parts that can interact in many different ways so that the whole takes on a life of its own: it adapts and evolves in response to changing conditions. It can be prone to sudden and seemingly unpredictable changes—a market crash is the classic example. One or more trends can reinforce other trends in a “positive feedback loop” until things swiftly spiral out of control and cross a tipping point, beyond which behavior changes radically.

What makes a “complex system” so vexing is that its collective characteristics cannot easily be predicted from underlying components: the whole is greater than, and often significantly different from, the sum of its parts. A city is much more than its buildings and people. Our bodies are more than the totality of our cells. This quality, called emergent behavior, is characteristic of economies, financial markets, urban communities, companies, organisms, the Internet, galaxies and the health care system….

The trouble is, we don’t have a unified, conceptual framework for addressing questions of complexity. We don’t know what kind of data we need, nor how much, or what critical questions we should be asking. “Big data” without a “big theory” to go with it loses much of its potency and usefulness, potentially generating new unintended consequences.

When the industrial age focused society’s attention on energy in its many manifestations—steam, chemical, mechanical, and so on—the universal laws of thermodynamics came as a response. We now need to ask if our age can produce universal laws of complexity that integrate energy with information. What are the underlying principles that transcend the extraordinary diversity and historical contingency and interconnectivity of financial markets, populations, ecosystems, war and conflict, pandemics and cancer? An overarching predictive, mathematical framework for complex systems would, in principle, incorporate the dynamics and organization of any complex system in a quantitative, computable framework.

Lockheed Martin Throws More Dirt on Malthus’ Grave || via Meadia

Cheap, clean water may soon be available for the whole planet. According to Reuters, defense contractor Lockheed Martin has developed a filter that will hugely reduce the amount of energy necessary to turn sea water into fresh water. The filter, which is five hundred times thinner then others currently available, lets water pass through but blocks all salt molecules. It will use almost 100 times less energy than other methods for making salt water drinkable, giving third world countries another way of expanding access to drinking water without having to create costly pumping stations.

An Energy Coup for Japan: ‘Flammable Ice’ || New York Times

Japan said Tuesday that it had extracted gas from offshore deposits of methane hydrate — sometimes called “flammable ice” — a breakthrough that officials and experts said could be a step toward tapping a promising but still little-understood energy source.

The gas, whose extraction from the undersea hydrate reservoir was thought to be a world first, could provide an alternative source of energy to known oil and gas reserves. That could be crucial especially for Japan, which is the world’s biggest importer of liquefied natural gas and is engaged in a public debate about whether to resume the country’s heavy reliance on nuclear power.

Experts estimate that the carbon found in gas hydrates worldwide totals at least twice the amount of carbon in all of the earth’s other fossil fuels, making it a potential game-changer for energy-poor countries like Japan. Researchers had already successfully extracted gas from onshore methane hydrate reservoirs, but not from beneath the seabed, where much of the world’s deposits are thought to lie.

The exact properties of undersea hydrates and how they might affect the environment are still poorly understood, given that methane is a greenhouse gas. Japan has invested hundreds of millions of dollars since the early 2000s to explore offshore methane hydrate reserves in both the Pacific and the Sea of Japan.

Intercontinental mind-meld unites two rats || Nature

The brains of two rats on different continents have been made to act in tandem. When the first, in Brazil, uses its whiskers to choose between two stimuli, an implant records its brain activity and signals to a similar device in the brain of a rat in the United States. The US rat then usually makes the same choice on the same task.

Miguel Nicolelis, a neuroscientist at Duke University in Durham, North Carolina, says that this system allows one rat to use the senses of another, incorporating information from its far-away partner into its own representation of the world. “It’s not telepathy. It’s not the Borg,” he says. “But we created a new central nervous system made of two brains.”

Nicolelis says that the work, published today in Scientific Reports, is the first step towards constructing an organic computer that uses networks of linked animal brains to solve tasks. But other scientists who work on neural implants are skeptical.

Manufacturing metals: A tantalising prospect || The Economist

ALUMINIUM was once more costly than gold. Napoleon III, emperor of France, reserved cutlery made from it for his most favoured guests, and the Washington monument, in America’s capital, was capped with it not because the builders were cheapskates but because they wanted to show off. How times change. And in aluminium’s case they changed because, in the late 1880s, Charles Hall and Paul Héroult worked out how to separate the stuff from its oxide using electricity rather than chemical reducing agents. Now, the founders of Metalysis, a small British firm, hope to do much the same with tantalum, titanium and a host of other recherché and expensive metallic elements including neodymium, tungsten and vanadium.

The effect could be profound….

The difference between its process and that of Hall and Héroult (and why electrolysis has not previously been used to make metals such as tantalum and titanium) is that the Hall-Héroult method requires both input oxide and output metal to be in liquid form. That demands heat. But aluminium has a fairly low melting point and its oxide can be dissolved in a substance called cryolite that also has a low melting point, so the amount of heat needed is manageable. Titanium and tantalum are not so obliging. The Metalysis trick is to do the electrolysis on powdered oxides directly, without melting them.

This was shown to be possible in 1997 when researchers at Cambridge University found that immersing small samples of certain oxides in baths of molten salt and passing a current through them transformed the material directly into metal.

World’s First Digital Laser Designed and Built in Africa || Technology Review

In principle, [lasers] are simple devices. They consist of a couple of mirrors, a source of energy, usually light, and a lasing cavity in which the light can bounce back and forth.   

The trick is to fill the lasing cavity with a material known as a gain medium which amplifies at a specific frequency when stimulated by light of another frequency. When this amplified light is directed out of the cavity, using a half-mirror, it forms a narrow beam of coherent light of a single specific frequency–a laser beam.

For many applications, the shape of this beam– the way the light intensity varies across the beam–is important.

Physicists currently change the shape by placing various kinds of beam-shaping devices in front of the laser. These include lenses, mirrors and digital holograms generated using spatial light modulators.

But because these devices are essentially bolted on to the front of a laser, they all require expensive custom optics that have to be calibrated each time they are changed.

Today, however, Sandile Ngcobo at the University of KwaZulu–Natal in South Africa and few buddies, say they’ve worked out a way round this. And they’ve designed and built a device to test their idea.

The solution is simple. Instead of putting  a spatial light modulator in front of the laser, they’ve built one in to the device, where it acts as the mirror at one end of the cavity. In this way, the spatial light modulator shapes the beam as it is being amplified.

The result is that the beam is already shaped in the required way when it emerges from the laser cavity…. The big advantage of all this is that the spatial light modulator generates patterns electronically. That allows these guys to change the beam shape at the touch of a button and without any of the time-consuming set up required with other methods.

You May Have Been Born to Flock || Wired

In “Spontaneous flocking in human groups,” a paper published in the January issue of Behavioral Sciences, Boos and colleagues describe an attempt to isolate underlying flocking mechanisms hinted at by the large-scale behaviors sometimes seen in crowds.

Her team designed an experiment in which test subjects were allowed to move within a virtual space, but with the identities of other people completely hidden. Other people were literally seen as black dots.

Despite the impossibility of exchanging information or social cues, people in the experiment drifted towards each other in predictable, mathematically regular ways. These are hints, said Boos, of the fundamental forces of spatial attraction that exist between people….

“We see collective behavior in many aspects of human society,” said Couzin. “If you observe a crowd from above, you see that pedestrians spontaneously form lanes, following the slipstream of others. There’s lots of patterns that arise from local interactions that we’re not aware of.”

IBM's Warmth-Activated Gel Can Break Up Tough Bacterial Biofilms And Kill Superbugs || Popular Science

Drug-resistant bacteria present a couple types of problems—they don’t die when attacked with typical antibiotics, and they form slimy, hard-to-remove colonies called biofilms, meaning they literally stick around after you’ve tried to wash them off. New treatments to prevent their spread have to take a different approach from other antimicrobial products. Researchers at IBM have a new idea, and they say it could work in hospitals, countertops and on your skin.

The new antimicrobial hydrogel, made of 90 percent water, gloops together spontaneously when warmed to body temperature. It can bust through biofilms and kill a whole host of bacterial types, from small bugs like E. coli to large bugs like methicillin-resistant Staphylococcus aureus. The hydrogel is comprised of specially designed polymers, which are biodegradable and positively charged. When mixed with water and warmed up, the polymers self-assemble into chains, and the result is a thick gel.

The research team, led by Yi-Yan Yang at the Singapore-based Institute of Bioengineering and Nanotechnology, says the gel can be incorporated into creams, thin-film coatings for medical instruments, wound treatments, and plenty of other uses.

Their key breakthrough is the way the material hunts down and kills its quarry. Rather than interfering with DNA or selectively binding to a bacterial cell wall, like antibiotics do, the polymers grab on to the cell wall and rip it open, letting the contents leak out. This is possible because of their positive charge—matching the negatively charged cell wall of a microbe—and their hydrophobicity, or avoidance of water. Bacteria stand no chance, and they can’t evolve resistance to this method of attack the way they could evolve resistance to the proteins found in drugs. It’s a physical attack.

How Science Invented a Remarkable New Harder-Than-Diamond Nanomaterial || Wired

Ultrahard nanotwinned cubic boron nitride,” describes how researchers from the University of Chicago, the University of New Mexico, Yanshan University, Jilin University, and Hebei University of Technology compressed a form of boron nitride particles to an ultrahard version.

The transparent nuggets that resulted rivaled — and even exceeded — diamond in their hardness, according to tests run by the researchers. With a Vickers score of 108 GPa, it surpasses synthetic diamond (100 GPa) and more than doubles the hardness of commercial forms of cubic boron nitride.

The secret is in the nanostructure. Yongjun Tian and the other researchers started with onion-like boron nitride particles shaped a bit like a flaky rose — or, as Tian describes them, like Matryoshka dolls. When they compressed them at 1,800 Celsius and 15 GPa (around 68,000 times the pressure in a car tire), the crystals reorganized and formed in a nanotwinned structure.

In a nanotwinned crystalline structure, neighboring atoms share a boundary, the way neighboring apartments do. And like some apartments, the twins mirror each other.

An Antipodean Raj || The Economist

The first Australians thus arrived about 45,000 years ago. After that, it took until 1788, when Captain Arthur Phillip, RN, turned up in Sydney Cove with a cargo of ne’er-do-wells to found the colony of New South Wales, for gene flow between Australia and the rest of the world to be resumed.

This storyline was called into question a few years ago by the discovery, in some aboriginal Australian men, of Y chromosomes that looked as though they had come from India. But the details were unclear. Now a study by Irina Pugach of the Max Planck Institute for Evolutionary Anthropology, in Leipzig, and her colleagues, which has just been published in the Proceedings of the National Academy of Sciences, has sorted the matter out. About 4,000 years before Captain Phillip and his merry men arrived to turn the aboriginals’ world upside down, it seems that a group of Indian adventurers chose to call the place home. Unlike their European successors, these earlier settlers were assimilated by the locals. And they brought with them both technological improvements and one of Australia’s most iconic animals.

Sealed Under Turkish Mud, a Well-Preserved Byzantine Chapel || New York Times

In the fourth century A.D., a bishop named Nicholas transformed the city of Myra, on the Mediterranean coast of what is now Turkey, into a Christian capital…. After some 800 years as an important pilgrimage site in the Byzantine Empire it vanished — buried under 18 feet of mud from the rampaging Myros River. All that remained was the Church of St. Nicholas, parts of a Roman amphitheater and tombs cut into the rocky hills.

But now, 700 years later, Myra is reappearing.

Archaeologists first detected the ancient city in 2009 using ground-penetrating radar that revealed anomalies whose shape and size suggested walls and buildings. Over the next two years they excavated a small, stunning 13th-century chapel sealed in an uncanny state of preservation. Carved out of one wall is a cross that, when sunlit, beams its shape onto the altar. Inside is a vibrant fresco that is highly unusual for Turkey.

The chapel’s structural integrity suggests that Myra may be largely intact underground. “This means we can find the original city, like Pompeii,” said Nevzat Cevik, an archaeologist at Akdeniz University who is director of the excavations at Myra, beneath the modern town of Demre.

Mark Jackson, a Byzantine archaeologist at Newcastle University in England, who was not involved in the research, called the site “fantastic,” and added,“This level of preservation under such deep layers of mud suggests an extremely well-preserved archive of information.”

Occupied since at least the fourth century B.C., Myra was one of the most powerful cities in Lycia, with a native culture that had roots in the Bronze Age. It was invaded by Persians, Hellenized by Greeks, and eventually controlled by Romans.