Purple sea urchins feast on the remains ofBut a new sequence of the California purple urchin's genome reveals that the marine creatures and humans bear a striking number of similarities. (See related photo: "Sea Urchin Genome Decoded".)
"Comparing all the genes of the sea urchin, it's actually quite similar to us," said George Weinstock, who led the sequencing project. Weinstock is co-director of the Human Genome Sequencing Center at Baylor College of Medicine in Houston, Texas.
The sea urchin is one of the few marine organisms whose genome has been sequenced. The study therefore also provides insights into the vital role of sea urchins in many marine ecosystems.
"Sea urchins are major grazers in shallow seas of many parts of the world's oceans ... and they are the main prey of many top predators," said John Pearse, a biologist at the University of California, Santa Cruz.
Results from the sequencing project and accompanying articles, including one by Pearse, will appear in tomorrow's issue of the journal Science.
Kelp Forests
Sea urchins, which feed mainly on algae, live in environments that alternate between species-rich kelp forests and sea urchin-dominated "barrens."
"They are known to limit sea grass and kelp production and consequently the diversity and complexity in communities supported by these producers," Pearse said.
He compares sea urchins to rabbits and other grazers found on land.
"Sea urchins are the main prey of many top predators—including crabs, lobsters, fish, and sea otters—that directly limit their abundance, comparable to how coyotes, hawks, and owls limit the abundance of rabbits," Pearse said.
With a diminishing population of sea otters in California's Monterey Bay, for example, the population of sea urchins has multiplied. The sea urchins are reportedly chewing up the kelp forest in the area and upsetting the ecosystem. (Related video: "Killer Whale Mystery at Monterey Bay".) There are other factors that influence sea urchins' ecological role, including interactions among different urchin species.
"Populations of some species tend to explode and devastate the communities they are in, while others rarely do so," Pearse said. "Knowledge of their genome might allow people to better understand the underlying mechanisms that lead to such differences."
Sea urchins can also be used by scientists to detect toxic chemicals.
"One of the things in the genome project has been to come up with a very detailed description of the defense mechanism that sea urchins have to deal with toxic chemicals," Weinstock, of Baylor College of Medicine, said.
"Understanding their sensitivities and resistances could potentially help fine-tune our use of them, in terms of understanding the marine environment."
Humans are also directly affecting sea urchin populations. Sea urchin roe, or ovaries, are a delicacy in Korea and Japan.
[November 2, 2006].)
Human Cousin?
The urchin's usefulness as a model for developmental biology was another major reason for the sequencing project.
Scientists have long used sea urchins to study fertilization and early development in humans.
"The series of steps that happen after an egg is fertilized by a sperm ... those very early events turn out to be the same in the sea urchin as they are in the human," Weinstock said.
The scientists identified more than 23,000 genes in the 814 million base pairs, or "letters," of DNA code taken from the sea urchin.
The sea urchin represents the first sequenced genome from the echinoderms, which are the closest known relatives of the chordates, the group that includes vertebrates, animals with spinal columns.
The genome includes analogs to many essential human genes that were previously thought to be exclusive to vertebrates.
But missing among the sea urchin genes are some genes found in flies and worms. This, scientists say, shows that sea urchins are closer kin to humans than beetles, flies, crabs, and clams.
"Humans and sea urchins have a common ancestor," Weinstock said.
The eyeless sea urchin also has genes associated with taste, smell, hearing, balance—and surprisingly, even vision.
Source : http://news.nationalgeographic.com
A company that developed technology capable of creating water out of thin air nearly anywhere in the world is now under contract to nourish U.S. soldiers serving in Iraq.
The water-harvesting technology was originally the brainchild of the Pentagon's Defense Advanced Research Projects Agency, which sought ways to ensure sustainable water supplies for U.S. combat troops deployed in arid regions like Iraq.
"The program focused on creating water from the atmosphere using low-energy systems that could reduce the overall logistics burden for deployed forces and provide potable water within the reach of the war fighter any place, any time," said Darpa spokeswoman Jan Walker.
To achieve this end, Darpa gave millions to research companies like LexCarb and Sciperio to create a contraption that could capture water in the Mesopotamian desert.
But it was another company, Aqua Sciences, that developed a product on its own and was first to put a product on the market that can operate in harsh climates.
"People have been trying to figure out how to do this for years, and we just came out of left field in response to Darpa," said Abe Sher, chief executive officer of Aqua Sciences. "The atmosphere is a river full of water, even in the desert. It won't work absolutely everywhere, but it works virtually everywhere."
Sher said he is "not at liberty" to disclose details of the government contracts, except that Aqua Sciences won two highly competitive bids with "some very sophisticated companies."
He also declined to comment on how the technology actually works.
"This is our secret sauce," Sher said. "Like Kentucky Fried Chicken, it tastes good, but we won't tell you what's in it."
He did, however, provide a hint: Think of rice used in saltshakers that acts as a magnet to extract water and keeps salt from clumping.
"We figured out how to tap it in a very unique and proprietary way," Sher said. "We figured out how to mimic nature, using natural salt to extract water and act as a natural decontamination.
"Think of the Dead Sea, where nothing grows around it because the salt dehydrates everything. It's kind of like that."
The 20-foot machine can churn out 600 gallons of water a day without using or producing toxic materials and byproducts. The machine was displayed on Capitol Hill last week where a half-dozen lawmakers and some staffers stopped by for a drink.
"It was very interesting to see the technology in action and learn about its possible implementation in natural disasters," said Rep. E. Clay Shaw Jr., a Republican from Florida whose hurricane-prone district includes Fort Lauderdale.
"It was delicious," Shaw said.
Jason Rowe, chief of staff to Rep. Tom Feeney, another Florida Republican, called the technology "pretty impressive."
"I was pretty blown away by the things it's able to do," Rowe said. "The fact that this technology is not tied to humidity like others are makes it an attractive alternative for military bases in the Mideast where humidity is not really an option.
"It seems like it's a cheaper alternative to trucking in bottled water, which has a shelf life," said Rowe, who described himself as a fiscal hawk.
Once deployed, the machines could reduce the cost of logistical support for supplying water to the troops in Iraq by billions of dollars, said Stuart Roy, spokesman of the DCI Group, Aqua Sciences' public affairs firm.
The cost to transport water by C-17 cargo planes, then truck it to the troops, runs $30 a gallon. The cost, including the machines from Aqua Sciences, will be reduced to 30 cents a gallon, Roy said.
Several systems on the market can create water through condensation, but the process requires a high level of humidity.
Aqua Sciences' machines only require 14 percent humidity, Roy said. "That's why this technology is superior and why they are getting the contracts."
"The army's explanation of weather balloons in the Roswell, New Mexico incident 60 years ago has been dealt a serious public relations blow. Late Army Lt. Walter Haut had signed a sealed affidavit prior to his death last year asserting that he had witnessed the wreckage of an egg-shaped craft and its extraterrestrial crew while working at the Roswell Army Air Field. An article at News.com.au reviews how Haut had worked as public relations officer for the Roswell base and was involved in the original weather balloon explanation of events at the time. This recent evidence would seem to confirm speculation that egg-shaped saucers are notoriously difficult to fly safely at low altitude." Source : Slashdot
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"Researchers in Japan have developed a display that makes 3D objects solid enough to grasp. The system, created by engineers at Japan's NTT, combines a 3D display with a haptic glove, making 3D items that look real but also feel solid to touch. Two cameras are used to image an object, to make the 3D image. A computer also uses this to render a solid representation. It could be used to inspect products remotely, or even to shake hands with someone on the other side of the world, the researchers say."
1928: W3XK, the first American TV station, begins broadcasting from suburban Washington, D.C.The station was an outgrowth of the work done by Charles Francis Jenkins in devising a way to transmit pictures over the airwaves, a process he called "radiovision." He sold several thousand receiving sets, mostly to hobbyists, and, after receiving permission to start an experimental TV transmitting station, aired programming five nights a week until shutting down in 1932.
Jenkins essentially brought the wrong technology to the field: His receiving sets relied on a 48-line image projected onto a 6-inch-square mirror to create the picture, rather than using electronics, the technology that determined the future of television.
An interesting aside: Jenkins was also the first to air a television commercial. He was fined by the government for doing so, a practice that was discontinued, unfortunately, as the medium matured.
Source : http://www.wired.com
"The Register is reporting that the UK government has stated there is no place in the science curriculum for Intelligent Design and that it can not be taught as science. 'The Government is aware that a number of concerns have been raised in the media and elsewhere as to whether creationism and intelligent design have a place in science lessons. The Government is clear that creationism and intelligent design are not part of the science National Curriculum programs of study and should not be taught as science.'"
The molten-rock layer is 10 miles thick and can’t be seen, felt or smelt from the surface. Researchers Daniel Toffelmier and James Tyburczy of Arizona State University found the layer using a relatively new technique that measures changes in weak electrical currents flowing through the Earth’s mantle rock.
The current is created when the solar wind, a continuous flow of charged atomic particles emitted by the sun, interact with Earth’s magnetic field, called the magnetosphere.
The chemical make-up of the rocks affects their conductivity. By measuring changes in the current at different depths, the scientists were able to detect distinct rock layers, including the "invisible" magma layer.
“Rocks are semiconductors,” Tyburczy said. “And rocks with more hydrogen embedded in their structure conduct better, as do rocks that are partially molten.”
The discovery, detailed in the June 21 issue of the journal Nature, partially confirms a recent hypothesis by two Yale University geoscientists, which states that a band of molten magma circles the Earth about t 250 miles beneath the planet’s crust, near a hypothetical “transition zone” separating the planet’s two mantle layers.
The idea is that as the rock rises from the lower mantle to the upper mantle, it expels all the water in its crystal structure and melts.
The researchers detected the molten layer beneath Tucson, Arizona. They aren’t sure how far the sheet extends, but say there is little chance any of the molten rock will erupt at the surface.
The discovery only partially confirms the Yale scientists’ idea, since it reveals a molten magma layer only beneath one spot on the Earth. But “finding that sheet of melt-rock tells us we’re on the right track,” Tyburczy said.
Source : http://news.yahoo.com/
"When I went back to my geologist colleague Lin Tan's lab to check the skeleton, I was shocked," Xu wrote in his e-mail. "I said to Tan, 'It is not a sauropod, it is not a tyrannosaurus, it is a tyrannosaurus-sized oviraptor. We have a gigantic chicken!' " And that's the report the journal Nature is publishing today: the discovery of a creature Xu's team has named Gigantoraptor erlianensis, a giant birdlike dinosaur from the Gobi's Erlian basin, long known to science for its famous fossils and to prospectors for its vast oil reserves. From the fossil record, the world's leading paleontologists are now sure that all modern birds are descended from the dinosaurs; in fact, the scientists often term birds "modern dinosaurs." And paleontologists, studying the fossils marking the evolution of birds during the age of dinosaurs, have observed that as the birdlike dinosaurs approached birdness, they seem to have evolved into smaller and smaller types. So what's an enormous beast like Gigantoraptor doing among the avian world's ancestors? It's a curious twist in the long up-and-down saga of evolution that has intrigued science ever since the Cambrian explosion of 500 million years ago, when the ancestors of countless familiar life forms emerged -- in the short span of 10 million years. Said UC Berkeley's Kevin Padian, a leading expert on dinosaur evolution and curator of the university's Museum of Paleontology who has seen the report from Xu and Tan: "We have dwarf sauropods, so why not giant oviraptors (the term means 'egg thief')? If resources are available, all animals will take the opportunity to increase their size. Dinosaurs can get small, and dinosaurs can get big, and the bigger ones grow faster than the little ones, because getting bigger fast can reduce the number of predators around. "It all goes to show that when it comes to the diversity of dinosaurs, we're still just scratching the surface." The details in the report by Xu and Tan are fascinating: "Growth lines" in one bone showed that the creature grew to adult size in only seven years -- faster than most other two-footed, meat-eating dinosaurs and "probably died in the eleventh year of life." The animal had no teeth in its beak so its diet is a mystery, Xu said, because it had the relatively small head and long neck typical of plant-eaters, and the sharp claws of many meat-eaters. And while the fossil-hunters found no evidence of feathers -- as many dinosaur species show -- the beast could well have had feathered arms and feathers on its tail, most likely for sexual display. Finally, although most two-footed dinosaurs had stout legs to carry their weight, and short arms, Gigantoraptor's legs were relatively long and slender, and its arms were unusually long -- "more birdlike than its small relatives in many features," Xu said. Mark Norell at the American Museum of Natural History has hunted dinosaur fossils with Xu in the Gobi Desert in the past but was not involved in this discovery. He studied the Gigantoraptor's fossil bones last year at Xu's Institute of Paleontology and Paleoanthropology in Beijing. "It was really a surprise when I first saw it," Norell said in a telephone conversation. As dinosaurs evolved toward birds, they got smaller and smaller, their fossils show; until now, birdlike dinosaurs were at most 10 or 11 feet long -- certainly not 26 feet. Paul Sereno, a paleontologist at the University of Chicago who read the report, called it "a big find, really exciting -- a class act." "But what kind of environment on Earth was this animal adapted to?" he wondered. "It's off the charts, and with no teeth what did it eat? Did it use those long legs to escape from predators? It's clearly a pre-flight bird, but no one would have predicted its evolution, so the door seems open to a new way of living for a new kind of dinosaur." E-mail David Perlman at dperlman@sfchronicle.com. Source : http://www.sfgate.com
The taxonomy (that is, the classification) of the barnacle family, in addition to placing them in the phylum Arthropoda, also puts them in the class Crustacea and the order Cirripedia. Crustacea, in Latin, means "the shelled ones," and Cirripedia, roughly translated, means an animal with feet that are slender and wispy, like cirrus clouds.
 Stalked barnacle |
The most common barnacle belongs to the order Balanus. It is called the acorn barnacle (balanos, in Greek, means acorn). The species Balanus nubilus, found in Puget Sound, can reach a diameter of nearly a foot and is said to be good to eat.
Barnacles have existed since Jurassic times, the period in the earth's history during which dinosaurs lived. Fossils more than 150 million years old have revealed the presence of barnacles, whose ancestry can be traced back nearly 400 million years.
An eleventh century myth tells a story about one kind of barnacle, the goose barnacle (Lepas). The monks of those days were forbidden from eating meat during Lent, and they claimed that the barnacle goose, a bird, was simply a "grown up" goose barnacle. They argued that, being a fish, the barnacle goose could be eaten. Perhaps with a little imagination, the stalk, shell, and feathery cirri (feet) of the goose barnacle do look like those of an embryonic bird. in any event, the myth helped out those monks who wanted a hearty meal and gave the barnacle goose its name.
Barnacles live only in salt water. There are two kinds, the stalked barnacle (goose barnacle) and the nonstalked barnacle (acorn, or sessile, barnacle). Most barnacles are hermaphroditic; that is, they have both male and female reproductive organs. However, most barnacles must be fertilized by a neighbor, and that is one reason why they grow in large colonies. One scientist has estimated that the barnacles living along a half mile stretch of coastline can release a trillion young a year; many of these are eaten by other animals.
If barnacles are allowed to accumulate on a ship's hull, the ship will travel slower in the water, or it will have to burn more fuel to keep up its speed, than it would otherwise. A sixmonth growth of barnacles can result in having to burn 40 to 45 percent more fuel to maintain cruising speed. Removing barnacles from ships' hulls costs ship owners more than $125 million a year.
Although many new ideas have been tested, the best way to keep barnacles from growing on a ship's hull is still to paint the hull with copper bottom paint. The paint, which contains copper oxide, forms a toxic film that keeps cyprides (young, swimming barnacles) away from the hull.
The development of a barnacle takes place in two stages: a larval stage called the naupli, and a cyprides stage. In both of these stages of development the barnacles swim about freely, making up part of the mass of microscopic plants and animals collectively called plankton. During the later, cyprides stage they are attracted to other barnacles and use their front two antennae to crawl to a likely spot, where they will glue themselves and remain for life. The life span of most barnacles is from three to five years.
Inside its shell, the barnacle actually stands on its "head" and uses its "feet" to rake the plankton, which it eats. When the shell becomes too small to house the growing animal, a chemical is secreted which dissolves the inside of the shell and simultaneously builds up the outside. The barnacle's shell is made of limestone.
Barnacle cement, the substance the animals use to glue themselves to ships' bottoms and to rocks, has attracted the interest of doctors. A layer of this cement three tenthousandths of an inch thick over one square inch will support a weight of 7000 pounds. It is even stronger than epoxy cement. At temperatures above 6000°F the glue will soften but not melt, and at 380°F the cement will not crack. It does not dissolve in most strong acids, alkalies, organic solvents, or water. If man could learn to manufacture this cement, which barnacles have been using for millions of years, it could be used to mend broken bones and hold fillings in teeth.
The conversion method could not only make the otherwise daunting field of genomic coding more approachable to the general public and even children but could also provide scientists — including those who are vision-impaired — an entirely new way for analyzing proteins.
"It's a great teaching tool because everyone is familiar with music and it's a universal language," said research assistant Rie Takahashi, a microbiologist who studied classic piano for 14 years.
Takahashi developed the Gene2Music technique with microbiologist Jeffrey Miller at the University of California, Los Angeles, and published their results in the latest issue of Genome Biology 2007.
The team's initial study focused on the human thymidylate synthase A (ThyA), a protein involved in making and repairing DNA. Knowing the genetic pattern of a protein's amino acids (there are 20) is essential to understanding its function.
For example, some proteins have a pattern that causes them to repel water, while others attract water. That information that can ultimately help bioengineers develop more effective drugs.
It was too much to assign each of the 20 amino acids a unique note (the range would be two-and-a-half octaves), so Takahashi paired amino acids together into chords according to their water attracting or repelling capabilities. The result was 13 base notes, with the higher chords represented by the water-attracters and the lower keys represented by the water repellers.
Rhythm is determined by the three DNA letters that code for each amino acid in the protein. The more abundant the sequence of the three letters, the longer the duration a chord is played. So in the end, the chords and the rhythm say something about the protein's structure."Previous efforts have sought either to create works of art, and were directed primarily to the artistic community, or tried to evoke in the listener a sense of the 'music of the spheres' inherent in DNA," said Neil Smalheiser, assistant professor in psychiatry at the University of Illinois at Chicago.
"In contrast, the Gene2Music project shares the sensibility and mindset of the bioinformatics community, which seeks to create public, open source tools for discerning biologically meaningful patterns within protein and DNA sequences."
But there are many different ways of assigning amino acids to notes and rhythm, said Smalheiser, and the software is still at the demo stage.
"Right now their software converts arbitrary nucleotide sequences to amino acid sequences, and thus to music, regardless of whether the result is biologically accurate or not," he said.
Takahashi and Miller are working to improve upon the software so that different instruments could be assigned to unique sections of the genome as way to distinguish their function. Free software developed by team member Frank Pettit can be downloaded from the Gene2Music Web site: (http://www.mimg.ucla.edu/faculty/miller_jh/gene2music/home.html).
