A humble marine worm may hold the key to mending bones that have been shattered: a strong adhesive that the worm uses to build its shell, and which hardens despite the worm’s watery habitat. Sandcastle worms, Phragmatopoma californica, dwell in the intertidal zone where they construct a tubelike shell by gluing together bits of sand, broken shells and other mineral debris. The glue is secreted from a special gland and hardens in less than 30 seconds underwater, forming a leatherlike consistency over several hours [Science News].
Medical engineer Russell Stewart has been working on a synthetic glue modeled on the worm’s adhesive. He thinks the worm-inspired glue could be just the thing for piecing together the small fragments of bone that result from complex breaks that must be glued within the wet environment of the body. “There’s lots of synthetic adhesives in widespread use for other things, [but] there’s no adhesives used for deep tissue repair,” Stewart said. Current remedies are primarily mechanical fixes, such as screws, pins, and plates, which can be an inefficient method for repairing highly fractured bones [The Scientist].
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In chunks of rock quarried from a Russian mountain range, physicists have found perfect “quasicrystals,” a type of material that researchers previously thought could only be created in a lab. Quasicrystals display ordered arrangements and symmetries but are not periodic—that is, they are not defined by a single unit cell (such as a cube) that simply repeats itself in three dimensions [Scientific American]. Instead, quasicrystals have two different geometric structures that alternate, and that are organized in ways which create complex patterns and symmetries. When such a pattern is laid out in two-dimensions, the resulting design is often called Penrose tiling.
Quasicrystals were first created in the lab in 1984, and physicist Paul Steinhardt, a coauthor of the current study, says the hunt for naturally occurring quasicrystals began about 10 years ago. “The latest issue surrounding quasicrystals has been could nature ever make them? … When we make them in the lab we try very hard to make perfect quasicrystals, but nature has no such goal” [Discovery News]. The researchers put out a call to mineralogists around the world, asking them to send in likely rock samples for testing.
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Using a fancy piece of chemistry equipment to study the chemical composition of wine, European researchers have one-upped the sophisticated palates of wine connoisseurs. The researchers used ultra high resolution mass spectrometry to sort through all the chemical compounds present in wines that had been aged in oak barrels, and found that for each wine, they could determine which French forest the oak was cut from. No other approach – analytical or sensory – has been able to significantly discriminate wines according to the species or the origin of the oak used for the barrels before, they say [Chemistry World].
The findings could prove useful to wine connoisseurs and historians, the researchers said, concluding that their findings produced “chemical representations of the way such noble nectar can shape, on the (tongue) of the wine taster, some of the outlines of the scene of its birth” [AP]. Similar analyses could also be used to detect wine fraud, the researchers noted.
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“LOOK MOM NO ELECTRICITY.” That was the first message conveyed by a rudimentary new communication system that researchers are calling the “infofuse.” In a new study, researchers printed patterns of three different flammable metallic salts on a nitrocellulose fuse and then set the fuse on fire. As it burned, it emitted pulses of different colored light that can be interpreted with a Morse code system.
In the study, published in the Proceedings of the National Academy of Sciences, researchers explain that they developed a code for the alphabet, numbers and four special characters (a full-stop, comma, exclamation mark and the “@” sign) based on the presence or absence of one of the three metals in each dot. Extra coding information comes from the length of the dot, which determines the duration with which it burns, and the space between dots, where no colour is produced [New Scientist]. They placed dots of the three metals–lithium, rubidium, and caesium–on the paper using an ordinary ink-jet printer. When the infofuse was set alight, its precise patterns were “read” by an optical detector.
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Wouldn’t it be useful if an aging, weakening bridge started to turn red as a warning to structural engineers? That’s the potential inherent in a new invention from a team of chemists and materials scientists, who created a plastic that turns red when it’s exposed to stress. Ultimately, such color-changing polymers could be used as coatings on everything from bridges to airplane wings, alerting engineers when vital structures are near failure [ScienceNOW Daily News].
To make the red-alert plastics, researchers placed small ring-shaped molecules that they call “mechanophores” in the center of polymer chains. In response to mechanical force, these rings break, changing the color of the polymer [ScienceNOW Daily News].
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A new study has found higher than expected levels of a controversial plastics chemical in people who had fasted for 24 hours. This surprised researchers because the chemical, bisphenol A (BPA), was thought to be ingested when trace amounts leaked from plastic food containers and bottles, and researchers thought it quickly passed through the system.
The finding suggests that exposure to BPA may come from many different sources, not just food products, or that the body doesn’t metabolize the chemical as fast as has been thought, the researchers said…. “What this study shows is that either we are getting exposed to a lot more BPA than we thought, or it’s hanging around longer than we thought, or both,” said lead researcher Dr. Richard W. Stahlhut [HealthDay News].
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When two people get knocked off their feet by physical chemistry, their friends may offer this standard glib explanation: “It’s all about the pheromones.” But in fact, 50 years after the term “pheromones” was coined by biologists to refer to the chemical messages passed within many insect and mammal species, researchers still haven’t found proof that humans emit or detect such chemicals. In an essay in Nature [subscription required] marking the 50-year milestone, zoologist Tristram Wyatt sums up the state of the research, and reminds the gullible not to buy any love potions that boast of their pheromone content.
The first studies took place in 1959, when German researchers discovered a chemical called bombykol that’s secreted by female silk moths and that immediately sends males into a mating frenzy. Following that Nobel Prize-winning work, biologists proceeded to find pheromones “across the animal kingdom, sending messages between courting lobsters, alarmed aphids, suckling rabbit pups, mound-building termites and trail-following ants. They are also used by algae, yeast, ciliates and bacteria” [Wired News], Wyatt writes. Pheromones have been found to play a part not just in mating rituals, but also battles for dominance, warnings about approaching danger, and cooperative behavior.
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By tweaking chemical strands of RNA, researchers have taken another step towards understanding how life may have first evolved on our planet. A test tube based system of chemicals that exhibit life-like qualities such as indefinite self-replication, mutation, and survival of the fittest, has been created by US scientists…. “This is the very end of the line, where chemistry starts turning into biology” [Chemistry World], says researcher Gerald Joyce. Researchers have previously created RNA strands that replicated themselves for a while before grinding to a halt, but this experiment marks the first creation of RNA strands that continue to replicate themselves indefinitely, which set up the conditions that allowed for evolution.
In the modern world, DNA carries the genetic sequence for advanced organisms, while RNA is dependent on DNA for performing its roles such as building proteins. But one prominent theory about the origins of life, called the RNA World model, postulates that because RNA can function as both a gene and an enzyme, RNA might have come before DNA and protein and acted as the ancestral molecule of life [Astrobiology Magazine].
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A synthetic material that mimics the qualities of an iridescent opal may have wide-reaching technological applications, its creators say. With the application of an electric current the material can rapidly change to any color of the spectrum, and the developers, who said they’re ready to sell the technology today, added that their ‘photonic ink’ (P-Ink) material could soon be used in electronic books or advertising displays [ZDNet].
The synthetic material can be likened to an opal, a mineral that owes its variety of colours to its layered structure: regions with a high refractive index, in which light travels slowly, are interleaved with regions with a low refractive index. Light waves with a wavelength – or colour – similar to that of the space between layers are scattered in a way that gives opal its iridescent sheen [New Scientist]. The synthetic material has a similarly layered structure, but with the addition of a little voltage the space between the layers swells or shrinks, allowing for fine-tuned control of what color of light the material scatters.
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To truly assess the risks posed by a ubiquitous group of chemicals found in everything from vinyl shower curtains to bug spray, researchers need to study their cumulative impact on human health, declares a new report from the National Research Council, a group that advises the government on science and health policy. The chemicals, called phthalates, are used to make plastic products soft and flexible, and are also found in cosmetics, personal-care products, and even pharmaceuticals. In rodent studies exposure to phthalates has been shown to interfere with the development of the male reproductive system, causing infertility, reduced sperm production, undescended testes, penile birth defects and other reproductive-tract malformations [Science News].
Traditionally, health agencies have studied the risk of each chemical individually, but experts say such a process doesn’t accurately reflect human exposure. “It is extremely important to conduct cumulative risk assessments to protect public health,” said [phthalate researcher] Dr. Sheela Sathyanarayana…. “Unlike in scientific experiments, humans are exposed to multiple chemicals everyday,” she said, so combining the chemicals “can help identify how these multiple exposures could be leading to health outcomes in the general population” [Scientific American].
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Researchers have created a strong, light-weight ceramic inspired by the composition of seashells, and say their new material could one day replace the aluminum alloys used in aerospace engineering. A seashell may seem like a fragile thing, but the iridescent mother-of-pearl coating on the inside of many shells has surprising toughness. Natural mother-of-pearl, also known as nacre, has a brick-and-mortar structure: Layers of “bricks” made from a calcium carbonate mineral are held together by thin films of a biopolymer “mortar” such as chitin [Chemical & Engineering News].
Researchers have tried to mimic this brick-and-mortar structure for years, but copying natural laminated materials has proved difficult, despite the best efforts of many researchers, says [lead researcher] Robert Ritchie…. Those best efforts have resulted in only very thin films, not bulk specimens with real-world practicality [New Scientist]. Now, researchers have come up with an ingenious way to produce a synthetic in large chunks, and say the material is both strong and resistant to fracture.
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Over 4 billion years ago the young and barren Earth was being buffeted by meteor strikes, and that violent bombardment could have created the first amino acids that then gave rise to the origin of life on the planet, a new study suggests. The hellish temperatures and pressures generated when an extraterrestrial object strikes Earth at speeds of several kilometers per second are enough to shatter and vaporize rock…. Yet part of such an immense burst of energy can trigger chemical reactions that generate complex organic substances from basic inorganic ingredients, says Takeshi Kakegawa [Science News].
Previously, researchers have suggested that organic molecules may have been created elsewhere in the universe and were brought to Earth by meteors. But the new study, in which researchers simulated the impact of meteorites in the primordial ocean, argues that the organic molecules could have been synthesized from the inorganic molecules already present on the planet when the meteorites crashed into the ocean. Other researchers have suggested similar processes for the creation of organic molecules on Earth, including lightning strikes or chemical reactions surrounding hot, volcanic vents in the deep sea.
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Vials holding the results of a famous chemistry experiment conducted 55 years ago have been discovered in dusty cardboard boxes, and a new analysis of their contents has revealed fresh insights into a big question: the origin of life on earth. In 1953, chemist Stanley Miller tried to duplicate the conditions present on the primordial earth in laboratory flasks, and while some of his results were published to great acclaim, other results were packed away and forgotten–until now.
Miller’s classic experiment involved putting atmospheric components thought to reflect those of the early Earth (ammonia, hydrogen, methane, and water) in a closed system and stimulating that mixture with an electric current to mimic the effects of lightning storms. He generated a small number of biochemically significant compounds, including amino acids, hydroxy acids, and urea, showing that conditions of primitive earth can create the building blocks of life [Ars Technica]. These results generated considerable excitement, but later researchers argued that Miller was wrong about the composition of the young earth’s atmosphere, and the experiment was written off as a novelty.
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Three researchers who worked on a fluorescent protein found in jellyfish and developed it into a standard laboratory tool have been awarded the Nobel Prize in chemistry, the prize committee announced today. The three researchers, Osamu Shimomura, Martin Chalfie, and Roger Tsien, worked separately to first isolate the protein, which glows brightly when exposed to ultraviolet light, and then to develop ways to use it as a luminescent marker in the cells of other organisms.
Said the prize committee: “The remarkable brightly glowing green fluorescent protein, GFP, was first observed in the beautiful jellyfish, Aequorea victoria in 1962…. Since then, this protein has become one of the most important tools used in contemporary bioscience. With the aid of GFP, researchers have developed ways to watch processes that were previously invisible, such as the development of nerve cells in the brain or how cancer cells spread” [Reuters].
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A “sustainable chemical” company called Genomatica has developed a way to use sugar and genetically engineered bacteria to produce a common industrial chemical that’s usually produced using petroleum, and which is found in everything from Spandex to car bumpers. By using sugar from sugar cane as a feedstock, industrial chemical companies can get a cheaper alternative to petroleum-derived chemicals, while investing in processes that are less polluting and nontoxic, said Genomatica CEO Chris Gann [CNET].
Genomatica produces the chemical, 1,4-butanediol (BDO), by feeding pure glucose derived from sugarcane to E. coli bacteria, which has been engineered to produce BDO. “We have engineered the organism such that it has to secrete that product in order for it to grow,” says [company president] Christophe Schilling…. “The interests of the organism are aligned with our interests: It grows faster when it produces more” [Scientific American].
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