EVERYTHING OLD IS NEW AGAIN

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

I thought we’d take a little dip in the technology file for some interesting stories. As you’ve probably figured out, I get interested in the strangest things and I asked a friend of mine (she’s an Egyptologist) a question about the pyramids in Egypt. I said “What holds them together? Is it just the weight of the blocks?” And she told me that the blocks are actually held together with a concrete-like mortar.

Well, it turns out I’m not the only one interested in how they were constructed. Ole J. Bryn, an architect and researcher at the Norwegian University of Science and Technology (NTNU) says he has the answer to this ancient puzzle.

Researchers have been so preoccupied by the weight of the stones they tend to overlook two major problems: How did the Egyptians know exactly where to put the heavy building blocks? And how did the architects communicate detailed, highly precise plans to a workforce of 10,000 illiterate men?

What Bryn discovered was quite simple. He believes that the Egyptians invented the modern building grid, and separated the structure’s measuring system from the physical building itself. Bryn studied the plans from thirty Egyptian pyramids, and discovered a precision system that made it possible for the Egyptians to reach the pyramid’s apex point, with an impressive degree of accuracy. As long as an architect knows the main dimensions of a pyramid, he can project the building as he would with a modern building but using the building methods and measurements known from ancient Egypt.

If the principles behind Bryn’s drawings are correct, then archaeologists have a new "map" that demonstrates that the pyramids are not a bunch of heavy rocks with unknown structures but, rather, incredibly precise structures.

And it turns out the Egyptians weren’t the only precision builders. In the business of concrete making, what’s old is definitely new again. Almost 1,900 years ago, the Romans built what continues to be the world’s largest unreinforced solid concrete dome, the Pantheon. The secret turns out to be that the lightweight concrete used to build the dome had set and hardened from the inside out. This internal curing process enhanced the material’s strength, durability, resistance to cracking, and other properties so that the Pantheon continues to be used for special events to this day.

But it’s only in the last decade or so that internally cured concrete has begun to have an impact on modern world infrastructure. Internally cured concrete is now being used for pavement and to build bridge decks, parking structures, water tanks, and many other structures.

The virtues of internally cured concrete come from substituting light-weight pre-wetted absorbent materials for some of the sand and stones that are mixed with cement to make conventional concrete. When they’re dispersed through the mixture, these water-filled lightweight materials serve as reservoirs that release water to nearby hydrating cement particles.

According to one study, bridge decks made with internally cured, high-performance concrete have a service life of 63 years, as compared with 22 years for conventional concrete and 40 years for high-performance concrete without internal curing.

Unfortunately, using internally cured concrete increases the cost of a project by 10 to 12 percent. Of course this should be evaluated against the reduced risk of cracking, better protection against salt damage, and other improved properties that contribute to a more durable structure that has a longer life and lower life-cycle costs. The authors also say that using internally cured concrete could have substantial benefits in a reduced disruption to the traveling public during road construction.

Think we’ll see any internally cured concrete here on Guam any time soon? Nah, me neither!

THROUGH A GLASS CLEARLY

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

Greetings! Well, I thought we’d dip into the technology file today. We haven’t been there for a while and there’s actually some good news.

Although it isn’t the dangerous problem it can be in the temperate zones in winter, it’s still a hassle when your glasses fog up when you go from an air-conditioned building into Guam’s humid air. And if you aren’t lucky enough to have AC in your car, your windshield can fog up dangerously when it’s raining hard and you can’t roll down the windows.

So news from the Universite Laval in France is welcome indeed. Researchers there have published news of an innovation that could eliminate the fog on eyeglasses, windshields, goggles, camera lenses, and any other transparent glass or plastic surface. Fog forms on a surface when water vapor in the air condenses in fine droplets. It’s not a continuous film and a good anti-fog coating should prevent the formation of such droplets.

The researchers use polyvinyl alcohol, a hydrophilic (water-loving) compound that allows water to spread uniformly. The challenge is to firmly attach the compound to the glass or plastic surface. To accomplish this, researchers constructed a layered base and then added the anti-fog compound. The result is a thin, transparent, multilayered coating that doesn’t alter the optical properties of the surface. In addition, the chemical bonds that join the different layers ensure the hardness and durability of the entire coating.

Two patents already protect this invention, which has numerous potential applications, including vehicle windshields, camera lenses, binoculars and corrective lenses. Negotiations are already underway with a major eyewear company interested in obtaining a license for this technology.

Foggy glass. A new innovation could eliminate, once and for all, the fog on eyeglasses, windshields, goggles, camera lenses, and on any transparent glass or plastic surface. (Credit: iStockphoto/Chepko Danil)

Well, I’m certainly all for this innovation! It’s a real pain to walk outside and have everything go blurry! And now for some new technology that that could have an impact locally.

Your next new car hopefully won’t be a lemon, but it could be a pineapple or a banana. That’s because Brazilian scientists are using fibers from these plants to make new plastics for cars that are stronger, lighter, and more eco-friendly than plastics now in use.

The scientists are using these plants to produce "nano" cellulose fibers, so tiny that 50,000 could fit inside across the width of a single strand of human hair. Like fibers made from glass, carbon, and other materials, nano-cellulose fibers can be added to raw material used to make plastics, producing reinforced plastics that are stronger and more durable.

The researchers are using pineapple stems and leaves, banana leaves, coconut shell fiber, cattails, and sisal fibers produced from the agave plant. To prepare the nano-fibers, the scientists insert the plant material into a device like a pressure cooker. Then they add just the right chemicals and heat the mixture over several cycles, to produce a fine material that resembles talcum powder. The process is costly, but just one pound of nano-cellulose produces 100 pounds of super-strong, lightweight plastic.

The new plastics are very strong but much lighter than traditional plastics. The researchers believe that many car parts like dashboards, bumpers and side panels will be made of nano-sized fruit fibers in the future. They’ll reduce a car’s weight and that improves fuel economy.

Clear glasses and cars made from locally grown plants. Sounds good to me!

REMEMBERING 9/11

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

As you all know, this is the anniversary week of the terrorist attacks on the United States ten years ago. Although I certainly wasn’t at the World Trade Center on 11 September 2001, I do have a story to tell because I was in the air between Tokyo and Detroit when the planes hit their targets.

Our first inkling that something was wrong was when the pilot came on the intercom and said “Ladies and gentlemen, I regret to inform you that our flight has been diverted to Vancouver.” Loud sighs, some moans. In conversations with my seatmates, I found that we all assumed someone had an inflight medical emergency.

We landed at Vancouver, rolled to the terminal and sat there. And sat there. And sat there. After about an hour, the pilot came on the intercom again and told us what had happened, an announcement that was greeted by stunned silence.

We’d been in the airplane for about three hours when we were told we’d be deplaning, five at a time. When my turn came, I entered the jetway and saw five people sitting on the jetway floor. We were directed to sit down in front of one of them and completely empty everything we had brought on board. All electronics had to be opened or turned on. All bags were thoroughly inspected.

But that wasn’t the really interesting part. At the top of the jetway, completely blocking the entrance to the terminal was a very large young Mountie in full uniform. He had some kind of large rifle or machine gun and he was pointing it down the jetway . . . at us. The end of the gun was constantly moving from passenger to passenger. It was the first and hopefully the only time in my long and adventurous life that I’ve ever been searched at gunpoint.

After we repacked our bags we were escorted into the terminal by our searchers where we were all given a very thorough pat down. One of the men in the jetway with me was escorted into another room and we never saw him again.

We were eventually taken to a hotel in Vancouver and I must say at this point that every Canadian I met treated me and everyone that was with me with the utmost courtesy and respect. I think we were all in shock.

We spent the night in Vancouver and were bussed across the border to Seattle the next day. From there, the routine trip to two science conferences deteriorated into a two-week nightmare of long lines, hotel rooms and trying to get home. Everyone else, you see, got to take a bus or a train or rent a car, but me? I was stuck in the mainland until American air space was opened again.

I eventually wound up in Chicago (the final destination of my checked bag) staying with the friend I was supposed to be with for two days. It wound up being over a week. Although I was never in harm’s way, I have my own reasons for never forgetting 9/11!

And now I’d like to tell you a little story about an unsung tribute to the people who died on that dreadful day. As you know if you’ve followed this column for a while, we have two car-sized robots Spirit and Opportunity on the planet Mars. What you probably don’t know is that each robot has a grinder that bores into Martian rocks and those grinders were being built in lower Manhattan by employees of Honeybee Robotics in September 2001. Although they weren’t directly affected by the crashes, the people building the grinders found a find a special way to pay tribute to the thousands of victims who perished in the attack.

An aluminum cuff that serves as a cable shield on each of the rock grinders on the Mars robots was made from aluminum recovered from the destroyed World Trade Center towers and the cable shield on both rovers bears the image of an American flag.

Stephen Gorevan, Honeybee founder and chairman, and a member of the Mars rover science team said “That shield on Mars, to me, contrasts the destructive nature of the attackers with the ingenuity and hopeful attitude of Americans.”

Since landing on the Red Planet, both rovers have made important discoveries about wet environments on ancient Mars that may have been favorable for supporting microbial life. Although Spirit went silent last year, Opportunity is still going strong, and researchers plan to use its rock abrasion tool on selected targets around a large crater that the rover reached last month.

One day, both rovers will be silent. In the cold, dry environment of Mars, the onboard tributes to the victims of 9/11 could remain in good condition for millions of years and be the most lasting memorial of them all.

CHEMICAL TRACERS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

So, that bag of spinach you just took out of the fridge has been in there for a while. Is it still safe to eat? Would you like a spinach bag that changed color when harmful levels of bacteria were present? How about a device that could be implanted in your body that would monitor the sugar levels in your blood without those twice-daily finger pricks? It may sound like science fiction but researchers at Tufts University are designing such devices out of . . . silk.

Current optical devices are based primarily on glass, semiconductors and plastics. But the harsh solvents and extreme temperatures needed to make them make it impossible to incorporate bioactive sensing components into the devices. Chemical residues and lack of biodegradability also limit environmental and medical applications. Furthermore, biological components typically need to be stored at controlled temperatures to retain their activity.

Silk proteins are a natural for integrating optical and biological functions. They can be processed in water at ordinary temperatures and patterned to generate a wide range of optical elements, including ultrathin films, thick films, and tiny and large-diameter fibers. Silk proteins also offer excellent surface quality and transparency, which are necessary for high-quality optics. And equally important, they’re mechanically robust.

To make their devices, Tufts scientists boiled silkworm cocoons in water to extract the glue-like sericin proteins. The purified silk protein solution was poured onto holographic diffraction gratings with spacing as fine as 3600 grooves/mm. The cast silk solution was air dried to create solid silk films that were cured in water, dried and optically evaluated. A similar process was used to create lenses, microlens arrays and holograms.

Since the films are made at room temperature, any included biological receptors stay active after the solution has hardened into the film. The Tufts team embedded three very different biological agents in their silk solution: a protein (hemoglobin), an enzyme (horseradish peroxidase) and an organic pH indicator (phenol red). All three agents maintained their activity for long periods when the silk film was simply stored on a shelf. According to the Tufts researchers, this is truly amazing when you consider that the enzyme becomes inactive if left unrefrigerated for a few days. The researchers also discovered they could alter how light travels through the silk film with certain chemicals to create an optical signal for different kinds of biological activity.

Silk optics has captured the interest of the Defense Department, which has funded and been instrumental in enabling rapid progress of the research. If the military is interested, you can be sure that more advances are coming in this area. Silk rules!!

And in case you were planning on going on a crime spree in the mainland and then coming back here to the Marianas to hide, you might want to reconsider. Recent research has shown that the beverages you drink can be used to track your location through time.

The body removes hydrogen and oxygen atoms from the water and beverages you drink and uses them to make proteins, including the protein in hair. The proportions of the isotopes in hydrogen and oxygen vary geographically with higher values in low-latitude, low-elevation, or coastal regions, for instance, and lower values elsewhere.

The finding may help trace the origin of drinks or help criminal investigators identify the geographic travels of crime suspects and other individuals through analysis of hair strands.

IN YOUR HANDS

By Pam Eastlick

Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.

One of the wonders of nature is what’s at the end of your arm. The human hand is an amazing machine that’s capable of all sorts of astounding feats. It can pick up, clench and caress. Although you certainly take your hands for granted, just imagine what life would be without them.

Robots need hands too, and building them has been a real challenge. Now, researchers at Cornell University and iRobot (the makers of the absolutely awesome Roomba vacuum cleaner) have gotten together and made a robotic hand. Ah, you’re thinking, what’s at the end of my arm but made of metal, right? Well, not exactly. They made it out of coffee and a party balloon. Say whut??

They call it a universal gripper and not a hand, since it conforms to the object it’s grabbing rather than being designed for particular objects, said Hod Lipson, Cornell associate professor of mechanical engineering and computer science. He worked with Chris Jones at iRobot Corp.

"This is one of the closest things we’ve ever done that could be on the market tomorrow," Lipson said. The gripper could be used to dismantle explosive devises or to move potentially dangerous objects. It could also be used on robotic arms in factories and perhaps most importantly, on prosthetic limbs.

Here’s how it works: An everyday party balloon is filled with ground coffee and attached to a robotic arm. The coffee-filled balloon presses down and deforms around the desired object, and then a vacuum sucks the air out of the balloon, solidifying its grip. When the vacuum is released, the balloon becomes soft again, and the gripper lets go.

Coffee is a particulate material which means it’s made of a lot of individually solid particles. Particulate materials have what’s called a jamming transition. When the particles aren’t packed tightly together, they move around each other like a liquid, but when they’re tightly packed they become solid and can no longer slide past each other. You’ve seen this yourself if you drink vacuum-packed coffee which is hard as a brick until the package is unsealed.

"The ground coffee grains are like lots of small gears," Lipson said. "When they aren’t pressed together they can roll over each other and flow. When they are pressed together just a little bit, the teeth interlock, and they become solid. What’s particularly neat with the gripper is that here we have a case where a new concept in basic science provided a fresh perspective in a very different area — robotics — and then opened the door to applications none of us had originally thought about.”

As for the right particulate material, anything that can jam will do in principle, and early prototypes involved rice, couscous and even ground- up tires. They settled on coffee because it’s light but also jams well. Sand did better on jamming but was prohibitively heavy. What sets the jamming-based gripper apart is its good performance with almost any object, including a raw egg or a coin — both notoriously difficult for traditional robotic grippers.

Basic principles, new science. Let’s all give these researchers a big hand!

Graduate student John Amend, left, and associate professor Hod Lipson with the universal robotic gripper. (Credit: Robert Barker/University Photography)