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for January, 2010.
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Well, I figured since we did space last week, that this week it would be medicine or what ails the two-legged animal, but in fact, the bulging file turned out to be the one with the four-legged animals and the six-legged animals and the however-many-you’ve-got animals including the no-legged animals. And that’s where we’ll start.
My article several weeks ago about the giant snake invasion in the states generated a lot of controversy on The Deep website. Many people apparently feel that the snake invasion is a lot of hype generated by the National Park Service. I suspect they’re wrong, but there’s no question that we should all be VERY glad that the subject of our first tale isn’t going to slither into anybody’s garden any time soon!
THE SNAKE THAT ATE ????
In the afore-mentioned article, I shared my memories of Pete, a reticulated python I met in Thailand who had been fed a chicken every week. At the time I knew her (she was female, despite her name) Pete was 33 feet long and weighed over 300 pounds. But Pete was a midget compared to the largest snake ever found. That bad boy was as long as a school bus and as heavy as a small car and it was the top drawer predator in tropical ecosystems only 6 million years after that big rock took out the dinosaurs.
Scientists found partial skeletons of a snake they named “Titanoboa” in Colombia. From the bones, the researchers estimate that the snake was about 45 feet long. They also estimate that it weighed around 2,500 pounds!
The scientists also found many skeletons of giant turtles and extinct primitive crocodile relatives that likely were eaten by the snake. Prior to this research, there had been no fossil vertebrates found in tropical South America that dated from the period immediately after the extinction of the dinosaurs.
The impressive size of Titanoboa tells us that the temperatures along the equator were hotter than they are now during the period that followed the end of the long meteor-generated global winter that did in the dinosaurs. That’s because snakes and other cold-blooded animals are limited in body size by the ambient temperature of where they live, a point that no doubt gives hope to the people who stand to be invaded by tropical snake species in the states.
If you look at cold-blooded animals and their distribution on the planet today, the large ones are in the tropics, where it’s hottest, and they become smaller the farther away they are from the equator.
Based on the snake’s size, the team estimates that the mean annual temperature at equatorial South America 60 million years ago would have been about 91 degrees Fahrenheit, about 10 degrees warmer than today. The presence of outsized snakes and turtles shows that even 60 million years ago the foundations of the modern Amazonian tropical ecosystem were in place. Fossil hunting is usually difficult in the jungle-covered tropics because of the lack of exposed rock, but the fossils were found in the Cerrejon Coal Mine in Northern Colombia.
Hmmm . . . Snakes on a plane, snakes in a coal mine. Although Pete was my friend, she was safely in a cage, and she wasn’t big enough to eat me anyway. However, I would NOT want to meet Titanoboa any time soon!
This artist’s rendering of Titanoboa cerrejonensis demonstrates the great snake’s size. It is anticipated the boa spent much of its life in or near water. (Credit: Copyright Jason Bourque, University of Florida)
And since we’re talking about reptiles, let’s move on to a much smaller one and learn how it does something interesting.
LOOK, MA, I CAN FLY!
The Lacerta family of lizards is confined mostly to Europe although there are some species in Africa and Asia. They are the ‘original’ lizards and indeed, the word “Lacerta” is the Latin word for lizard.
Although we don’t have any species here on Guam, most of them look very much like skinks, and skinks and lacertids are closely related. Like skinks, most of them are ground-dwelling, but like our blue-tailed skink, some of them have taken to living in trees.
Strangely enough, there is also a blue-tailed lacertid and neon blue tailed tree lizards (Holaspis guentheri) leap from branch to branch as they scamper through trees in the African forest. It’s even been said that the tiny African tree lizards can glide. But without any obvious adaptations to help them to upgrade a leap to a glide, it wasn’t clear whether the reptiles really do take to the air and, if they do, how they remain aloft.
Researchers from the University of Antwerp, decided to find out whether neon blue tailed tree lizards can really glide. They began filming them along with gliding geckos (Ptychozoon kuhli) and the common wall lizard (Podarcis muralis) as the animals leapt from a 6 foot tall platform to see if the neon blue tailed tree lizards really could glide.
Unfortunately, filming the lizards was extremely difficult. When the researchers startled the small animals into leaping off the platform, they had little control over the animal’s direction, and couldn’t guarantee that it was parallel to their camera. It was also difficult to capture each trajectory with a single camera and tricky to get the lighting conditions right. But after weeks of persistence the team finally collected enough film of the leaping lizards to compare their performances.
At first, it didn’t look as if the African lizard was gliding any better than the common wall lizard. Both animals were able to cover horizontal distances of about 18 inches after leaping from the platform, while the gliding gecko covered distances greater than 3 feet, aided by its webbed feet and skin flaps. But when the team compared the lizards’ weights, they noticed there was a big difference between the common wall lizard and the tree lizard. The tiny tree lizard only weighed 1.5 grams, while the larger common wall lizard’s weight averaged 5 grams.
The team recalculated their data to include the masses of the lizards and discovered that the tree lizard was traveling about four inches farther than you’d expect if it were simply jumping off the platform. The tree lizard was definitely delaying its descent and landing more slowly than the common wall lizard; the tree lizard was gliding.
But how was the tree lizard able to remain airborne for so long? Maybe the lizard was squashing itself flat while gliding to increase its surface area and generate more lift. But when the team re-examined their footage, the tree lizard’s shape did not change. And when they calculated the amount of lift each lizard generated as they descended, it was clear that the tree lizard was unable to produce a lift force. The team then realized that instead of increasing its surface area to generate lift, the tree lizard is able to glide because it is so light. The tree lizard’s ‘wing loading’ (mass:surface area ratio) was the same as that of the gliding gecko (assisted by skin flaps and webbed feet) so the tree lizard was able to glide like a feather because it was almost as light as a feather.
Curious to discover the cause of all that lightness, the scientists contacted colleagues at the European Synchrotron Radiation Facility to scan all three lizards’ bodies. The X-rays showed that the tree lizard’s bones were packed full of air spaces, making the lizard’s skeleton feather light for gliding.
Researchers discovered that neon blue tailed tree lizards glide like feathers through the air. (Credit: Kristaan D’Aout)
This gliding ability is not, unfortunately a feature of house geckoes who fall with astounding regularity from the heights in my house and do the gecko cha-cha on my head.
So we’ve moved from the no-legs to the four-legs and now we move on to the eight-legs. And as the no-legs was the biggest snake, there’s something really big about the arachnid we’re going to talk about next. And since arachnids include the spiders, I think we’re all happy that these fellows don’t live here either!
MY WHAT BIG WEBS YOU WEAVE!
One of Guam’s biggest spiders, often referred to as ‘banana spiders’, are those yellow and black numbers that build big spider webs, most notably at your house when they get the chance and between power lines. Although all spiders are poisonous, without exception, most of them aren’t poisonous to YOU and the Argiopes (to give them their Latin name) won’t hurt you at all. They are death on mosquitoes and the other bugs that bug you, however and it’s a good idea to leave their webs intact where they aren’t actively interfering with your lifestyle.
Our spiders and the webs they build are good-sized, but they don’t hold a candle to the new Nephila species (golden orb weaver spider) researchers recently discovered in Africa and Madagascar. The findings show that this new species, on average, is the largest orb weaver known. Like our Argiopes, only the females are giants with a body length of 1.5 inches and a leg span of 4-5 inches.
More than 41,000 spider species are known to science with about 400-500 new species added each year. But for some well-known groups, like the giant golden orb weavers, the last valid described species dates back to the 19th century. Nephila spiders are renowned for being the largest web-spinning spiders. They make the largest orb webs, which often exceed 3 feet in diameter.
Giant golden orb weavers are common throughout the tropics and subtropics. There are thousands of Nephila specimens in natural history museums. Past taxonomists recognized 150 distinct Nephila species, but recent examination using the latest techniques has caused spider researchers to recognize only 15 species as valid.
Therefore researchers were surprised to find a giant female Nephila from South Africa in the collection of the Plant Protection Research Institute in Pretoria, South Africa, that did not match any described species.
Several expeditions were launched to South Africa to find this species, but all were unsuccessful, suggesting that perhaps the Nephila specimen, first collected in 1978, was a hybrid or perhaps an extinct species. In 2003 a second specimen from Madagascar was found in another museum suggesting that it was not a hybrid. But no additional specimens were found in more than 2,500 samples from 37 museums and it was assumed that the species seemed extinct. Then a male and two females were found in South Africa’s Tembe Elephant Park, and it became clear that the specimens were indeed a valid new species.
The researchers hope that new populations of this giant spider will be found in Africa or Madagascar, because the species seems to be extremely rare and its only reported habitat is a sand forest in Tembe Elephant Park. The data suggest that the species is rare and its range is restricted.
This photo shows a giant golden orb-web exceeding 1 meter in diameter: Nephila inaurata, Rodrigues, Indian Ocean. (Credit: Photo M. Kuntner)
Which is probably a good thing for you if you’re a spider-hater! But don’t be, they kill many more bugs than they do people!
Giant snakes and spiders. Oh my!
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Well, a check of the files reveals that a subject that’s closest to my heart needs some attention. I’m teaching Astronomy at the University this semester and as I tell my students “That’s the marvelous thing about Astronomy, it changes every single day”. So let’s take an imaginary ride into space and find out the latest news.
Let’s start our journey with the stars. Specifically the closest one to us. Do you know how many stars there are in our solar system? No, not billions or even millions: there’s just one star in our solar system and its name is Sol. Of course, most of us refer to it as the Sun and if it wasn’t for the atomic bomb in our back yard, we wouldn’t be here. Read on!
STARING AT THE SUN
Now if your parents raised you right, you know better than to do this. But even if you tried it when your parents weren’t looking, you figured out real fast why it wasn’t a good idea. It’s hard to examine the Sun because, well frankly, it’s awful bright! But there are new telescopes and new satellites that examine the Sun every day. The Sun is the most important thing in our lives and even little burps could have dire consequences for Earth’s inhabitants.
There’s a new boy on the block that will help us understand much more about the Sun. It’s called the Solar Dynamics Observatory (SDO) and it will be launched next month. Its successful deployment will trigger an avalanche of data.
“SDO will beam back 150 million bits of data per second, 24 hours a day, 7 days a week,” says Dean Pesnell of the Goddard Space Flight Center in Greenbelt, Md. That’s almost 50 times more science data than any other mission in NASA history. “It’s like downloading 500,000 iTunes a day.”
SDO is on a mission to study the sun in unprecedented detail. Onboard telescopes will examine sunspots and solar flares using more pixels and colors than any other observatory in the history of solar physics. And SDO will reveal the sun’s hidden secrets in a prodigious rush of pictures.
“SDO is going to send us images ten times better than high definition television,” says Pesnell, the project scientist for the new mission. A typical HDTV screen has 720 by 1280 pixels; SDO’s images will have almost four times that number in the horizontal direction and five times in the vertical. “The pixel count is comparable to an IMAX movie — an IMAX filled with the raging sun, 24 hours a day.”
Resolution is only half the story, though. Previous missions have photographed the sun no faster than once every few minutes. SDO will shatter that record.
“We’ll be getting IMAX-quality images every 10 seconds,” says Pesnell. “We’ll see every nuance of solar activity.” Because photography like this has never been attempted for the Sun, new discoveries about how the Sun does its business are just around the corner.
To help us understand how this might affect solar physics, Dr. Pesnell recalled a story about Eadweard Muybridge, the 18th century photographer, who won a famous bet with racehorse owner Leland Stanford. In those days, most people thought that horses kept at least one hoof on the ground even in full gallop. That’s how it appeared to the human eye.
“But when Muybridge photographed horses using a new high-speed camera system, he discovered something surprising,” says Pesnell. “Galloping horses spend part of the race completely airborne with all four feet are off the ground.”
There will be similar surprises from high-speed photography of the sun. The images could upend commonly held ideas about how sunspot form, what triggers solar flares, and how explosions ripple through the sun’s atmosphere.
The SDO has three main instruments. There are four visible light telescopes that will work in tandem to produce astounding pictures. There’s also an instrument that will map the Sun’s magnetic field to peek beneath the Sun’s surface using a technique called helioseismology. The third instrument will examine the Sun in ultraviolet. There have never been rapid-fire photos taken of the Sun in ultra-violet and this instrument is guaranteed to teach us new things.
SDO also has an interesting orbit. It’s geosynchronous and is stationary above a pair of dedicated radio antennas near Las Cruces, New Mexico. It’s also far enough away from the Earth that it has the Sun in its gun sights all the time. Not a single bit of data should be lost.
Get ready to change a whole bunch of ideas about your favorite star!
This is the sun photographed by an ultraviolet camera onboard NASA’s STEREO spacecraft. Solar Dynamics Observatory will expand scenes like this one to IMAX resolution. (Credit: NASA/STEREO)
Now we’ll move from a new satellite to an old mystery. How hot is the Sun? Well, it depends on what part of the Sun you’re talking about. The temperature of the interior is estimated to be around 15 million degrees Kelvin, seriously hot on anybody’s temperature scale.
The Sun’s surface is around 12,000 K, and to help the kids understand this, I tell them that the inhaled end of a cigarette is around 1,200 K. But the surface is where the mystery begins.
As you left the Sun’s surface in your seriously refrigerated spaceship and headed out into the solar system, you’d expect the temperature to steadily fall from 12,000 K to roughly 10 K around Neptune, but strangely enough that’s not what happens. Temperatures in the solar corona, the sun’s outer atmosphere, soar to around two million degrees K, a whole lot hotter than 12,000 K. The reason this happens has been a complete mystery since it was discovered. Now, we may finally have an answer. New observations made with instruments aboard Japan’s Hinode satellite reveal the culprit to be nanoflares.
Nanoflares are small, sudden bursts of heat and energy that happen inside material trapped in a magnetic tube called a coronal loop. Coronal loops are the fundamental building blocks of the thin, translucent gas that makes up the Sun’s corona.
One proposed theory said that steady heating of coronal loops with specific lengths and temperatures explained the corona’s two million degree temperatures. But observations showed that most coronal loops have much higher density than the steady heating model predicts. Newer theories were based on nanoflares which can explain the observed density. But no direct evidence of the nanoflares existed until now.
The researchers think when a nanoflare suddenly releases its energy, the plasma in the low-temperature, low-density strands becomes very hot—around 10 million degrees K—very quickly. The density remains low, however, so the emission, or brightness, remains faint. This heat flows to the base of the coronal loop, which heats up the dense plasma at the loop’s base. Because it is so dense at the base, the temperature only reaches about 1 million degrees K. The dense plasma expands up into the strand. Thus, a coronal loop is a collection of 5-10 million degree K faint strands and 1 million degree K bright strands.
The Hinode satellite has detected the superheated 10 million degree plasma for the first time, which can only be produced by the impulsive energy bursts of nanoflares. These nanoflares can explain most coronal heating.
I suspect that the scientists who operate the new SDO satellite will also be on the lookout for nanoflares. Will they find them? Who knows, but every satellite gives us new insight into the star that gives us life.
This false-color temperature map shows solar active region AR10923, observed close to center of the sun’s disk. Blue regions indicate plasma near 10 million degrees K. (Credit: Reale, et al. (2009))
And now it’s time to leave our automated eyes and ears behind and do some real exploring for ourselves. Well . . . sort of . . . .
BUT I ONLY HAVE A COUPLE OF HOURS!
Although I’m a great fan of science fiction of all sorts, one of the things movies and TV shows seem to have done is permanently warp everyone’s ideas of just how long it takes to get anywhere.
Kids in the Planetarium ask me, “Miss, how long would it take to get to (insert any one of several solar system bodies)?” My stock answer is “How fast are you going?” And they look at me. And I say “How long would it take to get to Agana?” And some brave soul will say “Ten minutes?” And I say “But how long will it take if you’re walking?”
Speed matters when you’re talking about solar system distances (and farther distances as well!). If you’re going to drive to the Sun at say, 60 mph, it will take you roughly 16 YEARS to get there. If you want to go to the closest star other than the Sun and you’re traveling at the speed our spaceships travel around the solar system right now (about 80,000 mph), it will take you about 100,000 YEARS and you will be very seriously DEAD.
So . . . how long will it take you to get to Mars? Again, that depends on your speed, but it also depends on where Earth and Mars are in their orbits. If we’re on the other side of the Sun from Mars, it will take you much longer to get there than if we’re on the same side.
So . . . how long? Starting this year, an international crew of six will take part in a grand adventure that will simulate the 520-day round-trip to Mars that will include a 30-day stay on the Martian surface. In reality, they will live and work in a sealed facility in Moscow, Russia, to investigate the psychological and medical aspects of a long-duration space mission.
The ‘mission’ is part of the Mars500 program that’s being conducted by the European Space Agency and Russia’s Institute of Biomedical Problems (IBMP) The scientists intend to study human psychological, medical and physical capabilities and limitations on long journeys in space. Yes, boys and girls, humans are FINALLY beginning to seriously prepare for future human missions to Mars.
The crew will follow a program designed to simulate a 250-day journey to Mars, a 30-day surface exploration phase and 240 days traveling back to Earth. For the ’surface exploration’, half of the crew will move to the facility’s Martian simulation module and the hatch to the rest of the facility will be closed.
I say BRAVO to the ESA and the Russians for this step forward. NASA???
A special isolation facility hosts the Mars500 study. (Credit: ESA – S. Corvaja)
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Greetings! Well, this week the technology file is bulging, so hang on for a jaunt into the wonderful worlds of music and building construction. And if that’s not a wonderful juxtaposition, I don’t know what is!
A Violin Sweetly Singing
Everyone knows the name Stradivarius, but everyone may not realize why that name is famous. Antonio Stradivari was, quite simply, the maker of the best violins in the world. And this is still true even though he lived in the 1600’s.
Musicians and scientists have tried for centuries to discover what gives a Stradivarius violin its astoundingly beautiful sound. Some new research has been done that may not only explain it, but give some insights on how to reproduce it.
Joseph Nagyvary, a professor emeritus of biochemistry at Texas A&M University, has been working to solve the Stradivarius mystery for 34 years and he is confident he has succeeded. Dr. Nagyvary first theorized in 1976 that chemicals used on the instruments, not just the wood and the construction, are responsible for the distinctive sound of these violins.
His controversial theory has now received definitive experimental support through collaboration with Renald Guillemette, director of the electron microprobe laboratory in the Department of Geology and Geophysics, and Clifford Spiegelman, professor of statistics, both Texas A&M faculty members.
Dr. Nagyvary assumed that the wood Stradivari used was aggressively treated with chemicals and the chemicals were what created the sound. He got very small wood samples from restorers working on Stradivarius violins (“no easy trick and it took a lot of begging to get them,” he adds). The results of the preliminary analysis, suggested that the wood was treated with unidentified chemicals. In the present study, the researchers burned the wood slivers to ash, the only way to obtain accurate readings for the chemical elements they contained.
They found numerous chemicals in the wood, among them borax, fluorides, chromium and iron salts. The presence of these chemicals points to a collaboration between the violinmakers and the druggists of the time. Stradivari would have treated the wood with chemicals to keep worms from eating his precious violins.
Antonio Stradivari (1644–1737) made about 1,200 violins in his lifetime and sold them only to the very rich, primarily the royalty. Today, there are about 600 Stradivarius violins remaining and they are valued at up to $5 million each.
Dr. Nagyvary, a native of Hungary who learned to play the violin by using an instrument that once belonged to Albert Einstein, has wondered for decades how Stradivari, with his rudimentary education and no scientific training, could have produced musical instruments with such an unequaled sound. He believes the current findings will be of great interest to art historians and musical instrument makers around the world and could change the process of how fine violins are made.
What makes a Stradivarius’ violin sound different from other violins? (Credit: iStockphoto/José Carlos Pires Pereira)
But there are other theories about the cause of the beautiful sound of the instruments created by the old masters. Read on.
There was a music contest last year that none of us heard about. And it occurred at a conference on forest husbandry, (science talk for “How to Manage Your Trees”). Not a noted venue for a music contest.
A gentleman named Francis Schwarze who is a researcher for the Swiss Federal Laboratories for Materials Testing and Research played his ‘biotech violin’ in a head to head contest with a Stradivarius and he won!
1 September 2009 was the day of reckoning for Schwarze and Swiss violin maker Michael Rhonheimer. The violin they created used wood treated with a specially selected fungus and they played it in a blind test against a violin made in 1711 by the master violinmaker Antonio Stradivari.
In the test, the British violinist Matthew Trusler played five different instruments behind a curtain, so the audience didn’t know which one was being played. One of the violins Trusler played was his own Stradivarius, worth two million dollars. The other four were all made by Rhonheimer. The wood of two of them was treated with the fungus and the other two were made of untreated wood.
A jury of experts, together with the conference participants, judged the tone quality of the violins. The top vote getter was ‘Opus 58’ one of the treated violins. Trusler’s Stradivarius was rated second, but most of the people who voted for ‘Opus 58’ thought it was the Stradivarius. Opus 58 had been treated with fungus for the longest time, nine months.
Judging the tone quality of a musical instrument in a blind test is, of course, an extremely subjective matter, since it is a question of pleasing the human senses. Since the beginning of the 19th century violins made by Stradivari have been compared to instruments made by others in blind tests, including one organized by the BBC in 1974. In that test, the world famous violinists Isaac Stern and Pinchas Zukerman and the English violin dealer Charles Beare were challenged to distinguish a Stradivarius made in 1725, two other instruments made in 1739 and 1846 and a modern instrument made by the English master violin maker Roland Praill. The result was rather sobering – none of the experts could correctly identify more than two of the four instruments, and in fact two of the jurors thought that the modern instrument was actually the Stradivarius.
Many experts feel the success of the “fungus violin” in the current contest represents a revolution in the field of classical music because talented young musicians will be able to afford a violin with the same tonal quality as an impossibly expensive Stradivarius. Fungal growth changes the cell structure of the wood, reducing its density and simultaneously increasing its homogeneity. The experts believe that a violin made of wood treated with the fungus has a warmer, more rounded sound.
The five instruments played during the test. Visually, there is very little difference between them.
Chemicals or fungus? It makes a difference in the world of music! And now we’ll turn our attention to more mundane things. Building construction! And our first consideration is a building material we’re all familiar with. Cement!
Cementing it all together
In the 2,000 or so years since the Roman Empire employed a naturally occurring form of cement to build a vast system of concrete aqueducts and other big building projects (think Coliseum), researchers have analyzed the molecular structure of natural materials and created entirely new building materials like steel, which has a well-documented crystalline structure at the atomic scale.
Oddly enough, the molecular structure of
cement hydrate — the paste that forms and quickly hardens when cement powder is mixed with water — has eluded all attempts at decoding, despite the fact that concrete is the most prevalent man-made material on earth and the focus of a multibillion-dollar industry.
Scientists long believed that at the atomic level, cement (or calcium-silica-hydrate) resembled the rare mineral tobermorite, which has an ordered geometry consisting of layers of infinitely long chains of three-armed silica molecules (called silica tetrahedra) interspersed with neat layers of calcium oxide.
But a research team from MIT has discovered that the calcium-silica-hydrate in cement isn’t really a crystal. It’s a hybrid that shares some characteristics with crystals and some with the amorphous structure of frozen liquids, like glass or ice.
At the atomic scale, tobermorite has horizontal layers of triangles interspersed with layers of stripes. But a two-dimensional look at cement hydrate shows layers of triangles with every third, sixth or ninth triangle turned up or down along the horizontal axis and reaching into the layer of calcium oxide above or below.
And it is in these messy areas – where breaks in the silica tetrahedra create small voids in the corresponding layers of calcium oxide – that water molecules attach, giving cement its robust quality. The flaws in the otherwise regular geometric structure provide some give to the building material at the atomic scale that transfers up to the macro scale. When under stress, cement has the flexibility to stretch or compress just a little, rather than snapping.
And since most of our houses here in the Marianas are built with cement and concrete, it’s a very good thing, given all our earthquakes that it has that little bit of flexibility!
Concrete being poured from a cement truck chute on a new sidewalk construction project. (Credit: iStockphoto/Mike Clarke)
And now a little story about a pig. Specifically one of the three little pigs, the last one. You remember, the one that made his house not of cement but straw . . . .
I’ll Huff and I’ll Puff and . . . . .
The cement industry is a major Earth pollutant. The manufacture of cement is responsible for about 5 percent of all carbon dioxide emissions worldwide, and new emission standards proposed by the U.S. Environmental Protection Agency could push the cement industry to the developing world.
Researchers are trying to come up with a way to reduce that carbon footprint and scientists at the University of Bath in England have made a house that could do that. It’s made of straw.
Well, it’s actually made of pre-fabricated straw-bale and hemp panels and strangely enough, has fire resistance as good as houses built of conventional building materials.
The scientists tested one of the pre-fabricated panels, for fire safety by exposing it to temperatures over 1000°C. To reach the required standard the panel had to withstand the heat for more than 30 minutes. Over two hours later — four times as long as required — the panel had still not failed.
The straw house will be monitored for a year to assess its insulating properties, humidity levels, air tightness and sound insulation qualities to assess the performance of straw and hemp as building materials.
Straw is a very good insulator and the house has reduced heating bills of up to 85% compared to a house of similar size made from conventional materials. In addition, straw is an ideal environmentally-friendly building material because it is renewable and is a by-product of existing farming production. Because the plant that becomes straw absorbs carbon dioxide as it grows, buildings made from it have a very low carbon footprint.
A house made of straw? One wonders how it would stand up to the ‘huff and puff’ of a typhoon.
BaleHaus at Bath is constructed from straw bale prefabricated panels and has a very low carbon footprint. (Credit: Image by Modcell — www.modcell.co.uk)
Welcome to The Deep science and technology column where we cover topics from the deep sea to deep space and beyond.
Greetings everyone. Well, we had quite a bit of feedback on last week’s article on snakes. Many people think that the spread of the giant snakes into the southern US will be impossible because of the winter conditions. I certainly hope they’re right!
There were also a few comments about my story about Pete, the reticulated python. Someone pointed out that a three-foot long snake would hardly weigh 30 pounds and I suspect they’re right. I didn’t know Pete back then and I suspect five or ten pounds would be much more realistic.
I never personally weighed Pete either and have no clue if the 300-pound figure in the days when I knew her was actually accurate, but I can tell you from personal observation that the 33-foot length was certainly close to the truth. When she raised her head to my eye level, most of her was still on the ground!
We’ll leave the animals behind this week and concentrate on the planet’s most populous large animal and their woes. [For you sticklers out there, notice that I did NOT say ‘most populous life form’ (bacteria) or ‘most populous animal’ (insects)].
Certainly at the top of human woes is cancer. This dreadful disease, where the body’s own cells go rogue (sorry, Ms Palin) seems to be on the upswing. But there’s hope on the horizon from some unexpected sources.
NEW HOPE FROM JEWELERY?
We’ve known for a long time that heat is an excellent weapon against cancer cells. But it’s hard to cook tumors without cooking the surrounding tissue too.
Now, researchers from MIT are using tiny particles of gold to home in on tumors. Then the gold absorbs energy from near-infrared light and re-emits it as heat. This destroys tumors with minimal side effects. The particles called gold nanorods, can be used to diagnose as well as treat tumors.
Cancer affects about seven million people worldwide, and that number is projected to grow to 15 million by 2020. Most cancer patients are treated with chemotherapy and/or radiation, which are often effective but can have debilitating side effects because it’s difficult to target tumor tissue.
Gold nanoparticles can absorb different frequencies of light, depending on their shape. Rod-shaped particles absorb light at near-infrared frequencies. This light heats the tiny rods but passes harmlessly through human tissue.
In the study, tumors in mice that received an intravenous injection of nanorods plus near-infrared laser treatment disappeared within 15 days. The mice survived for three months (the end of the study) with no evidence of reoccurrence. Mice with tumors who received no treatment or only nanorods or only laser heating didn’t have that kind of survival rate.
Once the nanorods are injected, they disperse uniformly throughout the bloodstream. The research team developed a polymer coating for the particles that allowed them to survive in the bloodstream longer than any other gold nanoparticles (the half-life is greater than 17 hours).
In designing the particles, the researchers took advantage of the fact that blood vessels located near tumors have tiny pores just large enough for the nanorods to enter. Nanorods accumulate in the tumors, and within three days, the liver and spleen clear any that don’t reach the tumor.
During a single exposure to a near-infrared laser, the nanorods heat up to 70 degrees Celsius, hot enough to kill tumor cells. Additionally, heating them to a lower temperature weakens tumor cells enough to enhance the effectiveness of existing chemotherapy treatments, raising the possibility of using the nanorods as a supplement to those treatments.
The nanorods could also be used to kill tumor cells left behind after surgery. The nanorods can be more than 1,000 times more precise than a surgeon’s scalpel, so they could potentially remove residual cells the surgeon can’t get.
The nanorods’ homing abilities also make them a promising tool for diagnosing tumors. After the particles are injected, they can be imaged using a technique known as Raman scattering. Any tissue that lights up, other than the liver or spleen, could harbor an invasive tumor.
Another advantage of the nanorods is that by coating them with different types of light-scattering molecules, they can be designed to simultaneously gather multiple types of information – not only whether there is a tumor, but whether it is at risk of invading other tissues, whether it’s a primary or secondary tumor, or where it originated.
The researchers are looking into commercializing the technology. Before the gold nanorods can be used in humans, they must undergo clinical trials and be approved by the FDA, which will be a multi-year process.
MIT researchers developed these gold nanorods that absorb energy from near-infrared light and emit it as heat, destroying cancer cells. (Credit: Photo / Sangeeta Bhatia Laboratory; MIT)
Some how I’d never considered using gold as a cancer killer. Gold is one of the most inert things we know about and I don’t think I’d worry too much about being injected with gold nanorods if I was staring cancer in the face.
But gold isn’t the only new option. A old drug that I take every day and that many of you take as well, has been found to have some astounding new side effects.
NEW HOPE FROM OLD DRUGS
Researchers at the Harvard Medical School have found a drug that not only reduced tumors, but prolonged remission in mice longer than conventional chemotherapy. It apparently works by targeting cancer stem cells. What is this new miracle drug? Metformin, also known as glucophage.
There is a growing body of evidence in cells, mice and people that metformin may improve breast cancer outcomes in people. In the current study, the diabetes drug seemed to work independently of its ability to improve insulin sensitivity and lower blood sugar and insulin levels, all of which are also associated with better breast cancer outcomes.
The results fit within the cancer stem cell hypothesis, an intensely studied idea that a small subset of cancer cells has a special power to initiate tumors, fuel tumor growth, and promote recurrence of cancer. Cancer stem cells appear to resist conventional chemotherapies, which kill the bulk of the tumor. The cancer stem cell hypothesis says you can’t cure cancer unless you also get rid of the cancer stem cells.
The possible usefulness of metformin against cancer supports an emerging idea that, in the vast and complex alphabet soup of molecular interactions within cells, there are a few biological pathways that may be important in the development of many different diseases.
In mice, pretreatment with metformin prevented the otherwise dramatic ability of human breast cancer stem cells to form tumors. In other mice, where tumors were allowed to take hold for 10 days, the dual therapy also reduced tumor mass more quickly and prevented relapse. In the two months between the end of treatment and the end of the experiment, tumors regrew in the mice treated with chemotherapy alone, but not in mice that had both chemotherapy and metformin. But in an interesting side note, metformin was ineffective in treating tumors when used by itself.
The researchers have applied for a patent for a combined therapy of metformin and a lower dose of chemotherapy, which is being tested in animals. Hopefully, the results will be very good and be in soon.
is rampant here on Guam and one of the unfortunate side effects of diabetes is kidney disease. There’s also some good news in that department.
NEW HOPE FROM GETTING OFF THE COUCH
Getting off the couch could lead to a longer life for kidney disease patients, according to a study that appeared in the Clinical Journal of the American Society Nephrology (CJASN). The findings indicate that, as in the general population, exercise has significant health benefits for individuals with kidney disease.
Many patients with chronic kidney disease die prematurely, but not from effects directly related to kidney problems. Because physical activity has known health benefits, researchers at the University of Utah looked into the effects of exercise on people with chronic kidney disease.
The study included 15,368 adult participants (5.9% of whom had chronic kidney disease [CKD]) in the National Health and Nutrition Examination Survey III, a survey of the US population. After answering a questionnaire on the frequency and intensity of their leisure time physical activity, participants were divided into inactive, insufficiently active, and active groups. On average, participants were followed for seven to nine years.
The researchers found that 28% of individuals with CKD were inactive, compared with 13.5% of non-CKD individuals. Active and insufficiently active CKD patients were 56% and 42% less likely to die during the study than inactive CKD patients, respectively. Similar survival benefits associated with physical activity were seen in individuals without CKD.
"These data suggest that increased physical activity might have a survival benefit in the CKD population. This is particularly important as most patients with stage III CKD die before they develop end stage renal disease," the authors wrote.
So, it looks like getting off that couch is good for everybody and now that I’ve finished this article, I’m going to do just that. Why don’t you join me?
Jim is, above all, a passionate eco-humanitarian who has developed his own science talk-radio show to inform The DEEP’s listeners about such newsy topics as global warming, shark-finning and reef protection as well as to explore earth’s many underwater and space mysteries.
sailing 12,000 miles and visiting five countries Jim is back here, ready to explore the depths of the ocean to the deepest frontier, space MORE>>
Lady Pam Eastlick is an expert in both the stars
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