Large Hadron Collider

* The Large Hadron Collider (LHC), the biggest and most complicated particle physics experiment ever seen, is nearing completion and is scheduled to start operating this year.
* The LHC will accelerate bunches of protons to the highest energies ever generated by a machine, colliding them head-on 30 million times a second, with each collision spewing out thousands of particles at nearly the speed of light.
* Physicists expect the LHC to bring about a new era of particle physics in which major conundrums about the composition of matter and energy in the universe will be resolved.

You could think of it as the biggest, most powerful microscope in the history of science. The Large Hadron Collider (LHC), now being completed underneath a circle of countryside and villages a short drive from Geneva, will peer into the physics of the shortest distances (down to a nano-nanometer) and the highest energies ever probed. For a decade or more, particle physicists have been eagerly awaiting a chance to explore that domain, sometimes called the tera­scale because of the energy range involved: a trillion electron volts, or 1 TeV. Significant new physics is expected to occur at these energies, such as the elusive Higgs particle (believed to be responsible for imbuing other particles with mass) and the particle that constitutes the dark matter that makes up most of the material in the universe.

The mammoth machine, after a nine-year construction period, is scheduled (touch wood) to begin producing its beams of particles later this year. The commissioning process is planned to proceed from one beam to two beams to colliding beams; from lower energies to the tera­scale; from weaker test intensities to stronger ones suitable for producing data at useful rates but more difficult to control. Each step along the way will produce challenges to be overcome by the more than 5,000 scientists, engineers and students collaborating on the gargantuan effort. When I visited the project last fall to get a firsthand look at the preparations to probe the high-energy frontier, I found that everyone I spoke to expressed quiet confidence about their ultimate success, despite the repeatedly delayed schedule. The particle physics community is eagerly awaiting the first results from the LHC. Frank Wil­czek of the Massachusetts Institute of Technology echoes a common sentiment when he speaks of the prospects for the LHC to produce “a golden age of physics.”

A Machine of Superlatives

To break into the new territory that is the tera­scale, the LHC’s basic parameters outdo those of previous colliders in almost every respect. It starts by producing proton beams of far higher energies than ever before. Its nearly 7,000 magnets, chilled by liquid helium to less than two kelvins to make them superconducting, will steer and focus two beams of protons traveling within a millionth of a percent of the speed of light. Each proton will have about 7 TeV of energy—7,000 times as much energy as a proton at rest has embodied in its mass, courtesy of Einstein’s E = mc2. That is about seven times the energy of the reigning record holder, the Tevatron collider at Fermi National Accelerator Laboratory in Batavia, Ill. Equally important, the machine is designed to produce beams with 40 times the intensity, or luminosity, of the Tevatron’s beams. When it is fully loaded and at maximum energy, all the circulating particles will carry energy roughly equal to the kinetic energy of about 900 cars traveling at 100 kilometers per hour, or enough to heat the water for nearly 2,000 liters of coffee.

The protons will travel in nearly 3,000 bunches, spaced all around the 27-kilometer circumference of the collider. Each bunch of up to 100 billion protons will be the size of a needle, just a few centimeters long and squeezed down to 16 microns in diameter (about the same as the thinnest of human hairs) at the collision points. At four locations around the ring, these needles will pass through one another, producing more than 600 million particle collisions every second. The collisions, or events, as physicists call them, actually will occur between particles that make up the protons—quarks and gluons. The most cataclysmic of the smashups will release about a seventh of the energy available in the parent protons, or about 2 TeV. (For the same reason, the Tevatron falls short of exploring tera­scale physics by about a factor of five, despite the 1-TeV energy of its protons and antiprotons.)

Four giant detectors—the largest would roughly half-fill the Notre Dame cathedral in Paris, and the heaviest contains more iron than the Eiffel Tower—will track and measure the thousands of particles spewed out by each collision occurring at their centers. Despite the detectors’ vast size, some elements of them must be positioned with a precision of 50 microns.

The nearly 100 million channels of data streaming from each of the two largest detectors would fill 100,000 CDs every second, enough to produce a stack to the moon in six months. So instead of attempting to record it all, the experiments will have what are called trigger and data-acquisition systems, which act like vast spam filters, immediately discarding almost all the information and sending the data from only the most promising-looking 100 events each second to the LHC’s central computing system at CERN, the European laboratory for particle physics and the collider’s home, for archiving and later analysis.

A “farm” of a few thousand computers at CERN will turn the filtered raw data into more compact data sets organized for physicists to comb through. Their analyses will take place on a so-called grid network comprising tens of thousands of PCs at institutes around the world, all connected to a hub of a dozen major centers on three continents that are in turn linked to CERN by dedicated optical cables.

Hydrogen Hypersonic Airplane!

A Mach-5 (3,400mph) plane from Reaction Engines A2, carries 300 passengers, fly twice as fast and at the same time be greener for the skies. Funded in part by the European Union’s Long-Term Advanced Propulsion Concepts and Technologies project (Lapcat), the airliner is desired to fly from Brussels to Sydney in less than four hours without producing a trace of harmful carbon emissions.

The A2 engine uses two modes, a combination of turbojet and ramjet propulsion systems, make the A2 efficient at slower speeds while giving it great speed capabilities. In the first mode, four Scimitar engines send incoming air through bypass ducts to turbines which produce thrust comparable to conventional jet engines and get the jet into the air to Mach 2.5. After it reaches Mach 2.5, the A2 switches into the second mode and incoming air is rerouted to the engine’s core. The air gets pushed through the engine with enough pressure to sustain combustion speeds of up to Mach 5.

It’s carbon footprint stands to be the biggest asset to the hydrogen-powered jet. It only produces water vapor and just a bit of nitrous oxide as exhaust. A hypersonic jet loaded with liquid hydrogen sounds a bit dangerous, but hydrogen fuel is no more explosive than normal jet fuel.

The biggest challenge they face is manufacturing hydrogen fuel on a large scale without emitting carbon in the process. Reaction Engines’s technical director, Richard Varvill, is hesitant to market it as a truly green machine till carbon-free production of hydrogen is reached.

Source:
http://www.popsci.com/military-aviation-space/article/2008-01/green-skies-mach-5

Mixing Mammals

Putting bat DNA into mice sheds light on how limbs evolved.

By outfitting mice with a chunk of DNA that directs wing development in bats, scientists have created rodents with abnormally long forelimbs, mimicking one of the steps in the evolution of the bat wing. Their work gives weight to the idea that variations in how genes are controlled, and not just mutations in the coding regions of genes, are a driving force in evolution.

The slightly longer forelimbs of the transgenic mice "make them more batlike," says Nipam Patel, a professor of molecular and cell biology and integrative biology at the University of California, Berkeley, who was not involved in the work. "It seems like a subtle difference, but evolution works by these subtle differences."

The researchers focused on a gene, Prx1, that plays a part in the elongation of limb bones in mammals. The gene's expression is regulated by another sequence of DNA, called a Prx1 enhancer. To investigate how the enhancer shapes limb development, Richard Behringer, a professor of molecular genetics at the University of Texas MD Anderson Cancer Center, and his colleagues around the country put the bat version of the Prx1 enhancer into mice so that it controlled the mouse Prx1 gene. These transgenic animals developed forelimbs that were on average 6 percent longer than normal by the time they were born. It was a significant difference, although "the mice look like mice," Behringer says. "They're not going to fly out of the cage." The researchers report their work in the latest issue of Genes and Development.

To have any chance of flying, mice would have to develop very different forelimbs, like those of bats, which are longer and have membranes stretched between the bones. Behringer says that he'd like to try replacing the limb enhancers in mice with those from other animals, such as whales or wallabies.

Charles Darwin contemplated the evolution of different kinds of limbs in On the Origin of Species. Starting with a basic limb pattern, "successive slight modifications," he wrote, eventually produce the various mammal limbs we see today: human hands, bat wings, whale fins.

"We think what we've done is made one of those slight modifications," Behringer says. "Maybe during evolution you'd have a lot of those and the limb would get a lot longer, and maybe some of the tissue would be retained between digits, ultimately leading to the structures that would allow a bat to fly."

"It's a very nice demonstration of something that people have been suspecting now for some time: that regulatory sequences rather than changes in protein sequences sort of drive evolution," says Susan Mackem, who heads the Developmental Biology Unit at the National Cancer Institute's Center for Cancer Research. Mackem was not involved in Behringer's research.

Behringer's team also found something unexpected. When the researchers created mutant mice that lacked the mouse Prx1 enhancer, the animals developed forelegs of a normal length. That suggests that more than one enhancer controls the expression of the Prx-1 gene in mice, ensuring what Behringer calls a "regulatory redundancy."

"As long as there is one copy to do the work, the other copy can be creative," says Ann Burke, an associate professor of biology at Wesleyan University.

http://www.technologyreview.com/

Instant Boot-Up

Many office workers have the same morning routine: turn on the computer, then grab coffee, catch up with coworkers, or look at paperwork while Windows boots up. Others save time, but waste energy, by keeping their machines on all the time.

Now Device VM, a startup based in Silicon Valley, has a product that circumvents the everlasting boot-up. The company has recently released a tiny piece of software that, when integrated with common computer hardware, gives users the option to boot either Windows or a faster, less-complex operating system called Splashtop. Depending on the hardware and Splashtop settings, a person using the software--which is based on the open-source operating system Linux--can start surfing the Web or watching a DVD in less than 20 seconds, and, in some cases, in less than five.

DeviceVM has formed partnerships with several hardware manufacturers, and Splashtop is already available on hardware from Asus, a manufacturer of motherboards, the main circuit boards inside computers. Within the next couple of months, desktops and laptops with Splashtop-enabled hardware will be available to consumers, says David Speiser, director of business development at DeviceVM.

Lengthy boot-ups on Windows machines occur for a number of reasons, explains Ben Chong, senior architect at DeviceVM. "First of all," he says, "Windows is pretty big." This means that it has megabytes of instructions to follow--from opening up applications to checking what's in memory. Most computers also come with extra software that Windows automatically loads at startup. "In many cases, Windows PC comes with a whole bunch of stuff you don't need," Chong says. "Starting all of the programs takes a lot of time." (Microsoft wasn't able to comment on Windows' startup times before this article went up.)

Hitting the power button on any computer loads software called the basic input-output system, or BIOS, which is often stored in flash memory. The BIOS checks for hardware drivers and sets up the operating system. Splashtop is embedded in the BIOS, so it starts before the operating system is up and running. The user sees a screen with a simple interface offering a handful of options, including launching the Firefox Web browser, a media player, Skype, or an instant-messaging program, or allowing Windows to boot. The applications are stored in a flash-memory chip on the motherboard, so they can be quickly accessed--even if the hard drive fails, Speiser notes.

DeviceVM is not alone in its effort to give people a way to bypass Windows. Phoenix Technologies, a company that develops BIOSes that run on many computers, recently announced a technology called HyperSpace, a lightweight operating system that launches at the same time Windows does. (DeviceVM is also developing a version of Splashtop that can boot alongside Windows.) HyperSpace is expected to be available in laptops in the second half of this year.

For its part, Intel is developing both hardware and software that will shorten boot times. "We see boot time as something in which there is room for improvement," says Steve Grobman, director of Intel's business-client architecture group. Intel is currently shipping Intel Turbo Memory, which boots Windows faster by caching data in flash memory instead of on the hard drive. It also consumes less power, which is a concern in mobile devices. Grobman says that Turbo Memory works in conjunction with software coming from Microsoft, called ReadyDrive and ReadyBoost.

Grobman adds that Splashtop also resembles the lightweight operating systems found on some mobile devices, which allow access to only a few applications at a time. "I think Splashtop's capability is the same concept, but it's making it a little bit more general purpose," since it works on desktop and laptop machines, Grobman says. "It's a positive development in that it's making the PC easier to use in certain circumstances."

Synthesizing a Genome from Scratch

In a technical tour de force, scientists at the J. Craig Venter Institute, in Rockville, MD, have synthesized the genome of the bacterium Mycoplasma genitalium entirely from scratch. The feat is a stepping stone in creating precisely engineered microbial machines capable of generating biofuels and performing other useful functions.

"It really is groundbreaking that you can synthetically build a genome for a bacterium," says Chris Voigt, a synthetic biologist at the University of California, San Francisco, who was not involved in the project. "It's bigger by orders of magnitude than what's been done before."

Biologists creating genetically engineered organisms now routinely order pieces of DNA that are 10,000 to 20,000 base pairs long--big enough to incorporate the genes for a single metabolic pathway. That allows researchers to engineer microbes that can perform specific tasks, but the ability to synthesize entire genomes could grant a whole new level of control over biological design. (See "Tumor-KillingBacteria.")

In the new study, scientists ordered 101 DNA fragments, encompassing the entire Mycoplasma genome, from commercial DNA synthesis companies. These fragments were designed so that each overlapped its neighboring sequence by a small amount; these overlapping stretches stick together, thanks to the chemical properties of DNA. Researchers then bound the fragments piece by piece, eventually generating the full 582,970 base pair Mycoplasma sequence. The findings were published Thursday in the online edition of Science.

"We consider this a second and significant step in a three-step process of our attempt to create the first synthetic organism," says Craig Venter, president of the Venter Institute. Venter and his colleagues ultimately want to create a minimal genome--one with the least number of genes needed to sustain life. Pinpointing the minimal genome will both shed light on key cellular processes and provide a base for designing sophisticated synthetic organisms. "We ultimately want to design cells that could function in a robust fashion to make unique biofuels," says Venter.

The researchers' next step will be to show that the synthetic genome functions as it should. "We have the whole genome assembled in a tube, but we need to transplant it into the cell of a different species to show that it can reboot the cell," says Hamilton Smith, a Nobel laureate who oversaw the project at the Venter Institute. Last year, Smith's group transplanted the genome of one species of Mycoplasma into another, demonstrating that this type of transplant is possible. (See "Transplanting a Genome.")

While the synthesis of a genome might be impressive from a scientific perspective, it is not yet a practical way to engineer microbes to make biofuels. Instead, several companies, including Synthetic Genomics, a biotech company founded by Venter to engineer microbes for energy, are using more traditional metabolic engineering techniques to generate fuel-producing bacteria. (See "Building Better Biofuels.") "What we're doing with synthetic chromosomes will be the design process for the future," says Venter.

Others in the field are excited about that prospect. "Being able to synthesize genomes opens up a new world," says Voigt. "You can build things on the scale of the genome." For example, he says, scientists are now engineering bacteria to perform different steps in the conversion of biomass into ethanol--one strain to break down the biomass, another to make ethanol. But ideally, scientists could put those processes together to create one organism that could eat biomass and spit out fuel. (See "The Price of Biofuels.") "That would require genome-scale design," Voigt says.

He likens the current project, which required multiple steps to glue the fragments together, to the last computers designed before automated manufacturing and microfabrication techniques were introduced. Similar advances are needed for more ambitious genome-synthesis projects. "We still need to develop 'one step' genome construction methods in order to reduce the costs and turn time of genome construction," says Drew Endy, a synthetic biologist at MIT.

"UNKNOWN" FACTS

*A rat can last longer without water than a camel.

*Your stomach has to produce a new layer of mucus every two weeks or it will digest itself.

*The dot over the letter "i" is called a tittle.

*A raisin dropped in a glass of fresh champagne will bounce up and down continuously from the bottom of the glass to the top.

*A female ferret will die if it goes into heat and cannot find a mate. I know some people like that!

*A duck's quack doesn't echo. No one knows why.

*A 2 X 4 is really 1-1/2 by 3-1/2.

*During the chariot scene in "Ben Hur," a small red car can be seen in the distance.

*On average, 12 newborns will be given to the wrong parents daily! That explains it!

*Donald Duck comics were banned from Finland because he doesn't wear pants.

*Because metal was scarce, the Oscars given out during World War II were made of wood.

*The number of possible ways of playing the first four moves per side in a game of chess is 318,979,564,000.

*There are no words in the dictionary that rhyme with orange, purple and silver.

*The name Wendy was made up for the book "Peter Pan." There was never a recorded Wendy before.

*The very first bomb dropped by the Allies on Berlin in World War II killed the only elephant in the Berlin Zoo.

*If one places a tiny amount of liquor on a scorpion, it will instantly go mad and sting itself to death.

*Bruce Lee was so fast that they actually had to s-l-o-w film down so you could see his moves.

*The first CD pressed in the US was Bruce Springsteen's "Born in the USA."

*The original name for butterfly was flutterby.

*The phrase "rule of thumb" is derived from an old English law which stated that you couldn't beat your wife with anything wider than your thumb.

*The first product Motorola started to develop was a record player for automobiles. At that time, the most known player on the market was the Victrola, so they called themselves Motorola.

*Roses may be red, but violets are indeed violet.

*By raising your legs slowly and laying on your back, you cannot sink into quicksand.

*Celery has negative calories. It takes more calories to eat a piece of celery than the celery has in it to begin with.

*Charlie Chaplin once won third prize in a Charlie Chaplin look-alike contest.

*Chewing gum while peeling onions will keep you from crying.

*Sherlock Holmes NEVER said "Elementary, my dear Watson."

*An old law in Bellingham, Washington, made it illegal for a woman to take more than 3 steps backwards while dancing.

*The glue on Israeli postage is certified kosher.

*The Guinness Book of Records holds the record for being the book most often stolen from Public Libraries.

*Astronauts are not allowed to eat beans before they go into space because passing wind in a spacesuit damages them. Not to mention the other drawback.

*Bats always turn left when exiting a cave.

Controlling Cell Behavior with Magnets

For the first time, researchers have demonstrated a means of controlling cell functions with a physical, rather than chemical, signal. Using a magnetic field to pull together tiny beads targeted to particular cell receptors, Harvard researchers made cells take up calcium, and then stop, then take it up again. Their work is the first to prove that such a level of control over cells is possible. If the approach can be used with many cell types and cell functions, it could lead to a totally new class of therapies that rely on cells themselves to make and release drugs.

The research, which appeared in the journal Nature Nanotechnology, was led by Donald Ingber, professor of pathology at Harvard Medical School and cochair of the Harvard Institute for Biologically Inspired Engineering. Ingber's group demonstrated its method for biomagnetic control using a type of immune-system cell that mediates allergic reactions. Targeted nanoparticles with iron oxide cores were used to mimic antigens in vitro. Each is attached to a molecule that in turn can attach to a single receptor on an immune cell. When Ingber exposes cells bound with these particles to a weak magnetic field, the nanoparticles become magnetic and draw together, pulling the attached cell receptors into clusters. This causes the cells to take in calcium. (In the body, this would initiate a chain of events that leads the cells to release histamine.) When the magnetic field is turned off, the particles are no longer attracted to each other, the receptors move apart, and the influx of calcium stops.

"It's not the chemistry; it's the proximity" that activates such receptors, says Ingber.

The approach could have a far-reaching impact, as many important cell receptors are activated in a similar way and might be controlled using Ingber's method.

"In recent years, there has been a realization that physical events, not just chemical events, are important" to cell function, says Shu Chien, a bioengineer at the University of California, San Diego. Researchers have probed the effects of physical forces on cells by, for example, squishing them between plates or pulling probes across their surfaces. But none of these techniques work at as fine a level of control as Ingber's magnetic beads, which act on single biomolecules.

"Up to now, there hasn't been much control [over cells] at this scale," says Larry Nagahara, project manager in the National Cancer Institute's Alliance for Nanotechnology in Cancer and a physics professor at Arizona State University.

Many drugs, from anticancer antibodies to hormones, work by activating cell receptors. Once a hormone is in the blood, however, there's no turning it on or off. "This shows that you can turn on and off the signal, and that you can do it instantly," says Christopher Chen, a bioengineer at the University of Pennsylvania. "That's something that's hard to do, for example, with an antibody."

Ingber has many ideas for devices that might integrate his method of cellular control. Magnetic pacemakers could use cells instead of electrodes to send electrical pulses to the heart. Implantable drug factories might contain many groups of cells, each of which makes a different drug when activated by a magnetic signal. Biomagnetic control might lead to computers that can take advantage of cells' processing power. "Cells do complex things like image processing so much better than computers," says Ingber. Ingber, who began the project in response to a call by the Defense Advanced Research Projects Agency for new cell-machine interfaces, acknowledges that his work is in its early stages. In fifty years, however, he expects that there will be devices that "seamlessly interface between living cells and machines."

Other researchers agree. Ingber's biomagnetic control "may represent a new mechanism for man-machine interfaces," says UC San Diego's Chien. But before such interfaces can be developed, says University of Pennsylvania engineer Chen, researchers need to learn a lot more about cells.

"Say we have cells on a chip and we know what behavior we want to elicit," such as getting a stem cell to enter a wound site and initiate repairs, says Chen. "We don't know what signaling events have to happen to put the cell into the right state" so that it will take the desired action.

In the short term, Chen says that Ingber's method could help biologists gain crucial knowledge about cell signaling, such as how these signals are processed chemically and physically by the cell, and how they lead to particular outcomes, from calcium uptake to changes in gene expression. "It provides a tool that lets us tweak the cell and see what happens," says Chen.

By Katherine Bourzac http://www.technologyreview.com