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Only a few percent of the 15 million or so cargo containers that enter the country every year are screened for nukes, a number that Congress mandates must be 100 percent by 2012. That benchmark is impractical using today’s tech, however. Standard detectors can miss nuclear material hidden behind lead or steel, and naturally radioactive cargo such as kitty litter gives false positives, requiring a labor-intensive hand-search.

A new detector from Decision Sciences, a security company in California, sees through anything and can scan a semi in less than a minute. It tracks muons, cosmic particles constantly bombarding Earth. Muons penetrate everything but are deflected more by heavy atoms such as uranium and plutonium. The detector tracks these deflections.

The company finished lab tests this spring and is now building detectors to deploy at several ports in the next year. “As long as it works quickly enough, it should fit the bill,” says Robert Dynes, a physicist at the University of California at San Diego who reviewed radiation detectors for Homeland Security. Tests indicate that the device should be speedy on real cargo, says Decision Sciences’s chief technology officer, Allan Wegner. And it’s nearly foolproof. Wegner can’t go into detail about its weaknesses (for obvious reasons), but he assures us that kitty litter and watermelons will no longer threaten national security.

How It Works

As muons come from the sky, they pass through the top detector, the truck and the bottom detector. The muons create ionization trails in the scanner's gas-filled detector tubes, which sensors record.

Heavy atoms, such as uranium and plutonium, deflect muons more than lighter ones do. If the angles of muons' entrance and exit paths vary by a wide magin, nuclear material could be present.

The detector also senses gamma radiation, which the computer combines with muon data to build a 3D view of suspicious muon-scattering objects, alerting customs agents exactly where to search.

The biotech company Alnylam announced in June that its drug ALN-VSP cut off blood flow to 62 percent of liver-cancer tumors in those 19 patients, by triggering a rarely used defense mechanism in the body to silence cancerous genes. Whereas conventional drugs stop disease-causing proteins, ALN-VSP uses RNA interference (RNAi) therapy to stop cells from making proteins in the first place, a tactic that could work for just about any disease. “Imagine that your kitchen floods,” says biochemist and Alnylam CEO John Maraganore. “Today’s medicines mop it up. RNAi technology turns off the faucet.”

Here’s another analogy: If DNA is the blueprint for proteins, RNA is the contractor. It makes single-stranded copies of DNA’s genes, called mRNA, which tell the cell to produce proteins. In 1998, scientists identified RNAi, a mechanism that primitive organisms use to detect and destroy virus’s double-stranded RNA and any viral mRNA. Mammals’ immune systems made RNAi’s antiviral function irrelevant (although all vertebrates, including humans, still use RNAi to regulate mRNA activity), but researchers found that introducing small segments of double-stranded RNA to cells could trigger the ancient mechanism and selectively halt the production of specific proteins.

That ability makes RNAi a potential fix for many diseases, including cancer, that arise when abnormal cells produce excessive amounts of everyday proteins. In theory, manipulating RNAi to kill proteins is simple. ALN-VSP, for example, consists of synthetic double-stranded RNA designed to match tumor mRNA that codes for two proteins: VEGF, which cancers overproduce to help grow new blood vessels, and KSP, which sets off rapid cell division. The researchers send the synthetic RNA into liver cells, and the body’s RNAi system kills both the synthetic RNA and any matching tumor-grown mRNA. Knock out the mRNAs coding for those proteins—which in the liver are produced only by cancer cells—and the tumor stops growing.

“We can turn off any one of 20,000 genes with RNAi,” says Bruce Sullenger, a molecular biologist researching RNAi at Duke University. “The challenge has been to get a drug into only the desired cells and not harm others.” Researchers have worried that a drug might disrupt normal protein production in a healthy cell, or that the immune system will destroy the drug before it reaches its target.

Alnylam overcame both concerns by packaging the drug in a fatty envelope that is absorbed primarily by the liver. This allowed doctors to administer the drug through the blood, rather than by an injection to one spot, which improves results by ensuring that the entire liver receives an even dose.

The technique’s ability to attack single genes could lead to drugs for the 75 percent of cancer genes that lack any specific treatment, as well as for other illnesses. Alnylam is already testing RNAi therapy for Huntington’s disease and high cholesterol in cell cultures; other researchers are tackling macular degeneration, muscular dystrophy and HIV. The potential has driven nearly every major pharmaceutical company to start an RNAi program.

Because the approach is fundamentally simple, RNAi therapy could be ready within two years, say experts including John Rossi, a molecular geneticist at City of Hope National Medical Center in California. Alnylam plans to enroll an additional 36 patients in the ALN-VSP trial and increase the dosage, but the early results are good enough to suggest that it could be among the first RNAi therapies to hit the market. “I think RNAi could work for anything,” Rossi says. “But even if it only works for liver cancer, it would be pretty good.” For liver-cancer patients who have been failed by chemotherapy and radiation and felt their harsh side effects, that would be wonder drug enough.

Aeros (Airborne Robotic Oil Spill Recovery System) is a fleet of airplane-deployed robots that cordon off the oil and use centrifuge-like oil/water separators to collect oil for refining. Each ’bot can purify up to 3,000 gallons of water a minute. Several could clean an 11-million-gallon, Exxon Valdez–size spill in a few days.

Global Response Group, Aeros’s developer, is building its first prototype robot to test on an experimental oil spill next year. The company is also in talks with the Chinese government to establish the first Aeros airbase, which will deploy ’bots to protect that country’s fishing waters from offshore drilling. It will cost $800 million, a small fee compared with the billions of dollars in damage that a spill can cause.

Spills present challenges for any cleanup. “Booms don’t work well with big waves,” says oil expert Greg McCormack of the University of Texas. But the industry is eager for new strategies, he says, and will embrace Aeros if the prototype works. Aeros’s inventor, Myron Sullivan, says it will. “It needs fine-tuning,” he says, “but the technology is proven. There will be another disaster. All we can do is prepare for it.”

How It Works
1. ’Bots Away! Planes drop minivan-size water-cleaning robots and inflatable booms near the spill site.
2. Trap the Spill Once inflated, the U-shaped booms surround the oil. Robots use GPS to get behind a boom’s flap, which directs water into the ’bot’s cleaning system.
3. Clean The robot sucks oily water into a cone that spins the liquids, sending denser water to the outside and creating a stream of oil in the center. Low pressure at one end draws oil away while the heavier—and 99 percent clean—water flows out the other side.
4. Collect the Black Gold A bladder collects the oil, which crews pick up later to recycle. One robot can clean up to 3,000 gallons of water per minute, scrubbing the affected area in just a few days.

Ibogaine, a brown powder derived from the African Tabernathe iboga plant, has intrigued researchers since 1962, when Howard Lotsof, a student at New York University and an opiate addict, found that a single dose erased his drug cravings without causing any withdrawal symptoms. Unfortunately, the hallucinogen can increase the risk of cardiac arrest, and the U.S. Drug Enforcement Agency lists it as a Schedule 1 substance, a classification for drugs like ecstasy and LSD with “no known medical value” and “high potential for abuse,” making it difficult to get federal funding to run clinical trials.

Animal tests, however, have shown the drug’s medicinal promise. “Rats addicted to morphine will quit for weeks after receiving ibogaine,” says Stanley Glick, the director of the Center for Neuropharmacology and Neuroscience at Albany Medical College. And addicts have reported positive effects in Mexico and Europe, where ibogaine therapy is legal. “Going cold turkey is horrible. There’s vomiting and diarrhea and pain and a constant drug craving,” says Randy Hencken, a drug user who was treated in Mexico. “After ibogaine, I didn’t feel any symptoms or cravings. I’ve been clean for nine years. Heroin and cocaine no longer have any power over me.”

Despite these successes, ibogaine lacks scientific credibility. “As great as ibogaine seems, no one knows exactly how effective it is as a treatment,” says Valerie Mojieko, the director of clinical research for the Multidisciplinary Association for Psychedelic Research (MAPS), a privately funded Massachusetts-based nonprofit. So starting this month, MAPS will enlist Clare Wilkins, the director of Pangea Biomedics, to run the first long-term study to gauge the drug’s lasting effects at her clinic in Mexico (where patients already pay $5,000 for the treatment). She will treat 20 to 30 heroin addicts and, for the next year, MAPS will subject them to psychological and drug tests to quantify ibogaine’s effectiveness.

The study will also help establish how to prescribe the drug safely. “Most psychedelics are relatively harmless,” says neurologist Deborah Mash of the University of Miami, “but ibogaine has a much narrower margin for error.” Mash runs an ibogaine clinic in St. Kitts and has treated more than 400 addicts without incident in the past decade. But in the early 1990s, overdoses of the drug at a clinic in the Netherlands led to several deaths, which ultimately scared off the National Institute of Drug Addiction (NIDA) from starting its own research program in the U.S.

From the limited research, though, scientists have two theories about how ibogaine works. Some say it’s purely biological—that ibogaine degrades into a compound that binds with opiate receptors in the brain to quiet cravings. Others believe that it is also psychological, with the “whole-life review” part of the hallucination providing perspective on the negative aspects of drug use, and so the subject strives to quit.

Regardless of the mechanism, proving ibogaine works is essential to winning approval and funding for clinical trials in the U.S. The sooner the better: Nearly seven million Americans abuse illicit drugs, costing the nation an estimated $181 billion a year in health care, crime and lost productivity.

The MAPS study should begin to answer questions about ibogaine’s efficacy and safety, but most experts think prescriptions are 10 to 15 years away. Until then, desperate patients will continue to seek out treatment in unregulated places such as Mexico, and that’s ideal for neither the patients nor the researchers. Rick Doblin, the founder of MAPS, hopes this study will force regulators’ hands. “If we can show great results, it could increase support for ibogaine clinics and maybe get NIDA interested again—because that’s who really should be doing this research.”

A research effort doubles as a shark-attack warning system

It’s not known how far great whites—whose worldwide numbers are estimated to be fewer than 3,500—migrate or if there’s a season when they spend more time near the coast, says Rory McAuley, a senior research scientist with Western Australia’s Department of Fisheries. McAuley hopes that the buoys, along with about 50 sensors on the ocean floor, will also reveal behavior. This information could help authorities better predict the monthly risk at beaches and restrict seasonal shipping routes to protect sharks from boats.

As a bonus, the work could give swimmers a heads-up when a great white is closing in. If a tagged shark swims within approximately a quarter-mile of a coastal buoy, the system sends a text to lifeguards on nearby beaches. Even swimming at top speed, it might take the dangerous fish a couple of minutes to reach shore, possibly enough time for the lifeguards to drop the phone and sunscreen and get folks out of the water.

The five-pound rock in question was discovered in 1984 in the Transantarctic Mountains and is known as the Allan Hills Meteorite, or ALH84001 in astrobiology circles. Many scientists considered the gray-green meteorite a dead end, but the NASA team never stopped studying it and, thanks to improved microscopy techniques, the case for life on Mars is stronger than ever. “You can almost feel the tide turning,” Thomas-Keprta says. “People are looking at our research again.”

The first time around, critics argued that the markings that resembled Earthly bacteria were too small to have been alive (bacteria of the same size have since been found here) and that the organic material in the rock formed in Antarctica. But the killing blow came in 2003. Thomas-Keprta’s group had asserted that magnetite crystals, structures that Earthly microorganisms make, were formed in the meteorite by Martian bacteria. In 2003, however, researchers ran computer models that indicated that geological processes occurring at temperatures too hot to sustain life could have created these magnetites.

Now science is again considering the possibility that ALH84001 is full of fossilized nano-ETs. In Thomas-Keprta’s new magnetite study, she used a focused ion beam to isolate a fraction of the magnetite. When she analyzed the sample’s chemical composition, she found that the magnetites were similar to those created by Earth microbes, and that their specific atomic makeup could not have formed at the high temperatures suggested by critics. “This doesn’t definitively show that the magnetites in ALH84001 are biological in origin,” says Dennis Bazylinski, a bacteriologist at the University of Nevada who refereed Thomas-Keprta’s paper. “But it does show that the thermal mechanism popular among those who think strongly that the magnetites do not have a biological origin is extremely unlikely. I think Kathie really put a nail in the coffin for that explanation.”

Convincing doubters that this means Mars was teeming with life, however, will be difficult. “ALH84001 is a really nice rock, full of lots of cool stuff about early Mars, but nothing in it points in the direction of life,” says David Blake, a NASA exobiologist who studied ALH84001 in the 1990s. “To look at a rock 140 million miles from where it formed and turn it into a whole world is tough.”

Recent studies by other groups of two other Martian meteorites, the Nakhla meteorite, found in Egypt, and Yamato 593, another Antarctic specimen, have yielded features similar to ALH84001. Later this summer, Thomas-Keprta will turn her ion beam on these rocks—which formed in a wet Martian environment ripe for microbes—in hopes of revealing whether it contains biological by-products, and possibly uncovering fossilized cell walls.

Even if ALH84001 really is the dead end some argue, the work has been worth it. Astrobiologists now know how incredibly difficult it is to discern biological agents from geological processes, saving researchers from a wicked learning curve when they someday get a bit of Mars itself on the table. In the next decade, the first sample return missions will bring back a pound of Martian soil, and unless it’s full of living microbes or space maggots, scientists will inspect it with the same methods developed for these meteorites. In the meantime, there are more than 200 pounds of Martian material on Earth. That’s a lot of rocks to practice on.

The five-pound rock in question was discovered in 1984 in the Transantarctic Mountains and is known as the Allan Hills Meteorite, or ALH84001 in astrobiology circles. Many scientists considered the gray-green meteorite a dead end, but the NASA team never stopped studying it and, thanks to improved microscopy techniques, the case for life on Mars is stronger than ever. “You can almost feel the tide turning,” Thomas-Keprta says. “People are looking at our research again.”

The first time around, critics argued that the markings that resembled Earthly bacteria were too small to have been alive (bacteria of the same size have since been found here) and that the organic material in the rock formed in Antarctica. But the killing blow came in 2003. Thomas-Keprta’s group had asserted that magnetite crystals, structures that Earthly microorganisms make, were formed in the meteorite by Martian bacteria. In 2003, however, researchers ran computer models that indicated that geological processes occurring at temperatures too hot to sustain life could have created these magnetites.

Now science is again considering the possibility that ALH84001 is full of fossilized nano-ETs. In Thomas-Keprta’s new magnetite study, she used a focused ion beam to isolate a fraction of the magnetite. When she analyzed the sample’s chemical composition, she found that the magnetites were similar to those created by Earth microbes, and that their specific atomic makeup could not have formed at the high temperatures suggested by critics. “This doesn’t definitively show that the magnetites in ALH84001 are biological in origin,” says Dennis Bazylinski, a bacteriologist at the University of Nevada who refereed Thomas-Keprta’s paper. “But it does show that the thermal mechanism popular among those who think strongly that the magnetites do not have a biological origin is extremely unlikely. I think Kathie really put a nail in the coffin for that explanation.”

Convincing doubters that this means Mars was teeming with life, however, will be difficult. “ALH84001 is a really nice rock, full of lots of cool stuff about early Mars, but nothing in it points in the direction of life,” says David Blake, a NASA exobiologist who studied ALH84001 in the 1990s. “To look at a rock 140 million miles from where it formed and turn it into a whole world is tough.”

Recent studies by other groups of two other Martian meteorites, the Nakhla meteorite, found in Egypt, and Yamato 593, another Antarctic specimen, have yielded features similar to ALH84001. Later this summer, Thomas-Keprta will turn her ion beam on these rocks—which formed in a wet Martian environment ripe for microbes—in hopes of revealing whether it contains biological by-products, and possibly uncovering fossilized cell walls.

Even if ALH84001 really is the dead end some argue, the work has been worth it. Astrobiologists now know how incredibly difficult it is to discern biological agents from geological processes, saving researchers from a wicked learning curve when they someday get a bit of Mars itself on the table. In the next decade, the first sample return missions will bring back a pound of Martian soil, and unless it’s full of living microbes or space maggots, scientists will inspect it with the same methods developed for these meteorites. In the meantime, there are more than 200 pounds of Martian material on Earth. That’s a lot of rocks to practice on.