Wednesday, April 25, 2007

Potentially Habitable Planet Found Around Another Star

You've probably heard by now, but scientists at the European Southern Observatory have announced that they have found the smallest planet yet around another star (other than around pulsars, which would be completely inhospitable to life). It's still bigger than Earth, about five times our mass, which means it would have a surface gravity about 1.6 times ours.

Most exciting, though, is that this planet is relatively temperate. It orbits a weak, red dwarf star (Gliese 581), that doesn't give off much heat. But it orbits close enough--about 6.7 million miles--to its parent star that its surface temperature is estimated to be between 0 and 40 degrees Celsius (32 to 104 degrees Fahrenheit).

It's too early to tell if the planet would be hospitable to life or--and how exciting is this?--if it already has life on it. All scientists know for sure is the planet's mass and distance from its parent star... the planet could be icy, with a much larger diameter and lower temperature. Or it could be shrouded in a very dense atmosphere, like Venus, in which case it would be extremely hot. But so far indications are good for the planet to be capable of sustaining liquid water, and thus capable of supporting life.

Gliese 581 is one of the one hundred closest stars to Earth, at only about 20.5 light years distant, in the constellation Libra. More resources should be put into probing stars in our stellar neighborhood, as it is quite possible that there are many, many more Earth-like planets to be found.

Over the next several years, several space-based missions will join the terrestrial telescopes that are already searching. Earlier this year, the ESA's COROT went into service studying the accoustical waves that ripple across the surface of stars as a result of planets orbiting around them, similar to tidal effects in our oceans here on Earth due to the orbit of the moon. Astronomers expect to find between 10-40 rocky worlds, together with tens of new gas giants, in each star field that COROT will observe. Every 150 days COROT will move to a new field and begin observing again.

Next to launch will be NASA's Kepler mission, currently scheduled for launch in October 2008. Kepler will essentially be a super-powerful photometer that measures the brightness of stars. When a planet passes between Kepler and its parent star, it will block a portion of the star's light, and Kepler will register this difference. It will do this for 100,000 stars over the course of its 4-6 year mission.

No sooner than 2015 or 2016, NASA will launch SIM Planetquest (formerly known as the Space Interferometry Mission), which will use interferometry to amplify the light of any planets and negate out the glare of the parent star to look for planets. The launch date for this mission has already been pushed back five times, and with NASA's science budget continuing to be squeezed, it's likely that it will be pushed back farther, or even cancelled.

NASA is also planning a pair of missions, called the Terrestrial Planet Finder missions. The first of these, the Visible Light Coronagraph (TPF-C), will collect starlight and the very dim reflected light from the planets. The telescope would have special optics to reduce the starlight by a factor of one billion, thus enabling astronomers to detect the faint planets. TPF-C could conceivably launch as early as 2014, but I wouldn't count on it.

The second TPF mission, the Infrared Optical Interferometer (TPF-I), will small telescopes on a fixed structure or on separated spacecraft floating in precision formation would simulate a much larger, very powerful telescope. The interferometer would utilize a technique called nulling to reduce the starlight by a factor of one million, thus enabling the detection of the very dim infrared emission from the planets. TPF-I could conceivably launch by 2020, but I doubt NASA will let it get that far.

Also on the far horizon is the ESA's Darwin mission, which would use three space telescopes flying in formation as an interferometer, similar to TPF-I. In addition to detecting Earth-sized planets, Darwin would be capable of determining their atmospheric content. Darwin is currently slated for a launch no sooner than 2020.

Some of these missions will never be launched for political or economic reasons, but the ones that do manage to make it to launch will bring potentially hundreds or thousands of discoveries of worlds outside our solar system, many of which may be capable of supporting human life.

Then we'll just need to find a way to get there.

Monday, April 23, 2007

Stop the Nonsense

Messenger RNA is used by the body to encode proteins based on the structure of certain genes. In mRNA as in DNA, genetic information is encoded in the sequence of four nucleotides arranged into codons of three bases each. Each codon encodes for a specific amino acid, except the stop codons that terminate protein synthesis.

But what happens if the DNA of the genes mutates, or becomes corrupted? Sometimes it causes the wrong proteins to be encoded. Sometimes, the DNA mutates in such a way that the Messenger RNA is prematurely truncated.

Example (thanks to Wikipedia):
Protein: Met Thr His Arg Ala Arg Ser Stop

Now, suppose that a mutation occurs in the DNA:

The RNA derives from the DNA (where UGA derives from TGA) In this case, UGA is a stop codon, so the protein produced by this interaction looks like this:
Protein: Met Thr His Stop

"Okay," you're saying, "but why go into all this detail?"

The answer is fairly simple. The type of mutation described above is called a "nonsense mutation." It has been estimated that n most genetic conditions, between 5-15 per cent of cases are caused by these types of mutations.

But a new drug by PTC Therapeutics, now in Phase II clinical trials, allows the cellular machinery to read through premature stop codons in mRNA, and thereby enables the translation process to produce full-length, functional proteins.

The drug, known as PTC124, has already had encouraging results in patients with Duchenne muscular dystrophy (the most severe form of muscular dystrophy) and cystic fibrosis. The drug has excited scientists because research suggests it should also work against more than 1,800 other genetic illnesses, including spinal muscular atrophy, hemophilia, lysosomal storage disorders, retinitis pigmentosa, familial hypercholesterolemia and some forms of cancer.

PTC124 won't be a cure-all for these types of conditions, but if it can be effective in 5-15% of cases, this could be one of the most promising new drugs of the decade.

Thursday, April 19, 2007

51 Things: No Left Turn

Number 45 on TIME Magazine's list of 51 Things We Can Do to only make right turns while driving. It sounds strange at first, but when you think about it, it starts to make sense. How much time do you spend sitting at green lights waiting for your chance to turn left? While you sit idling, your car is burning fuel, which wastes your money and contributes wasteful carbon to the global warming problem.

According to TIME, in 2004, UPS announced that its drivers would avoid making left turns. In metro New York, UPS has reduced CO2 emissions by 1,000 metric tons since January. Today 83% of UPS facilities are heading in the right direction; within two years, the policy will be adopted nationwide.

So plan your routes ahead of time to avoid making left turns. You could save yourself some money and do your part to fight global warming at the same time.

Tuesday, April 17, 2007

Hey Buddy, Wanna Be a Research Test Subject?

Sometimes the easiest way to contribute to scientific advancement is not to be the scientist, but to be the lab rat. Research projects across the country and around the world need subjects for their test and control groups. The two means they have for getting subjects into their tests is by recruiting and by accepting volunteers.

Recruiting happens when the researchers target people with specific conditions, usually by working through a network of doctors who treat whatever condition they are trying to treat. The doctors recruit the patients and, if the patients consent, the doctors sign them up for the trials and are usually available to administer the treatments and provide follow-up care as part of the study.

Volunteers, on the other hand, take a proactive step to contact the research center or some agent in order to volunteer for the trial. I use the term "volunteer" loosely here, because in many of these studies, the volunteers are compensated (in cash, free medical care during the study, or both).

There are several ways to find out about opportunities for you to participate in a research study. The first (and best) is to ask your doctor. My doctor works at a clinic where they do clinical research, and she takes part in a couple of studies, one of which she considered signing me up for (until she discovered that the samples of a cholesterol medication she was giving me lowered my cholesterol by a massive amount in just two months).

You can also volunteer by checking with a local testing center, such as those run by Covance, or by searching for available studies at, a site run by the National Institutes of Health. If you're looking for studies outside the U.S., Thomson Centerwatch maintains a list of actively recruiting clinical trials around the world.

Even if you volunteer directly, though, you should still check with your doctor before volunteering for any study.

Monday, April 16, 2007

Studies Pinpoint Cause of ALS

Two studies published in Nature Neuroscience may show new ways to treat the degenerative nerve disease amyotrophic lateral sclerosis (ALS), which slowly paralyzes its victims until they die.

Both studies showed that a specific type of nerve cells, called astrocytes, turn toxic when they carry a mutated gene called SOD1, which has previously been linked with ALS. When SOD1 is mutated in astrocytes, one of the nourishing proteins apparently turns toxic. When the researchers grew astrocytes with mutated SOD1, they killed the neighboring mouse motor neuron cells.

This research may lead to new methods of detecting ALS earlier, and eventually to options for arresting the progress of the disease by neutralizing the protein that causes the cells to die.

Friday, April 13, 2007

Hey Buddy, Wanna Be a Satellite Software Developer?

I know it's been a while since I wrote a post in this series, but I just found an exciting new opportunity for people like you and me to participate in the advancement of science and technology.

Wired Magazine reports on a new effort by NASA to develop software for satellites in the public domain through open-source software development projects.

The program was launched quietly last year under NASA's CoLab entrepreneur outreach program, created by Robert Schingler, 28, and Jessy Cowan-Sharp, 25, of NASA's Ames Research Center in Mountain View, California. Members of the CosmosCode group have been meeting in Second Life and will open the program to the public in the coming weeks, organizers said.

I'm pretty excited about this opportunity, personally. Not only am I a science-and-technology nerd (as should be obvious from reading this blog), but I'm also a software developer. CosmosCode is my chance to take part in the creation of software for satellites and actually contribute my knowledge and skills--as opposed to just my idle CPU cycles--to the advancement of the human race.

Thursday, April 12, 2007

3D Solar Cells Boost Efficiency, Reduce Size and Weight

A team of researchers at the Georgia Tech Research Institute has designed new three-dimensional solar cells that absorb almost all of the light that hits them and could boost the efficiency of photovoltaic (PV) systems while reducing their size, weight and mechanical complexity.

The GTRI photovoltaic cells trap light between their tower structures, which are about 100 microns tall, 40 microns by 40 microns square, 10 microns apart -- and built from arrays containing millions of vertically-aligned carbon nanotubes. Conventional flat solar cells reflect a significant portion of the light that strikes them, reducing the amount of energy they absorb.

Because the tower structures can trap and absorb light received from many different angles, the new cells remain efficient even when the sun is not directly overhead. That could allow them to be used on spacecraft without the mechanical aiming systems that maintain a constant orientation to the sun, reducing weight and complexity – and improving reliability.

The researchers caution that there is still some work to be done on improving the designs. However, at least two efforts to commercialize this technology are already in the works.

Wednesday, April 11, 2007

51 Things: Plant a Fence

Number 26 on TIME Magazine's list of 51 Things We Can Do to fight global warming now is to plant a bamboo fence. Bamboo makes an attractive fence, and it consumes more carbon than many other plants when allowed to grow.

Most homeowners have to restrict its growth, lest it get out of control. Do this, however, and you reduce bamboo's capacity as a carbon sink. Only large-scale plantings, which absorb CO2 faster than they release it, can favorably tip the scales.

Planting a fence also saves on the carbon production that would have gone into manufacturing a fence from wood, metal, or plastic.

If you have a homeowners' association, make sure you check with them before planting your fence.

New Promise for Diabetes Treatment Using Stem Cells

A new research study treated fifteen young diabetics in Brazil, all suffering from Type I diabetes, with stem cells drawn from their own blood. Though too early to call it a cure, the procedure has enabled thirteen of the young people, who have Type I diabetes, to live insulin-free so far, some as long as three years.

"It's the first time in the history of Type 1 diabetes where people have gone with no treatment whatsoever ... no medications at all, with normal blood sugars," said study co-author Dr. Richard Burt of Northwestern University's medical school in Chicago.

While the procedure can be potentially life-threatening, none of the 15 patients in the study died or suffered lasting side effects. But it didn't work for two of them.

Larger, more rigorous studies are needed to determine if stem cell transplants could become standard treatment for people with the disease once called juvenile diabetes. It is less common than Type 2 diabetes, which is associated with obesity.

Read the full article by AP Medical Writer Lindsey Tanner here.

Saturday, April 7, 2007

Nanogenerator Provides Continuous Direct Current

Researchers at Georgia Tech have developed a prototype nanometer-scale generator that produces continuous direct-current electricity by harvesting mechanical energy from such environmental sources as ultrasonic waves, mechanical vibration or blood flow. Based on arrays of vertically-aligned zinc oxide nanowires that move inside a novel “zig-zag” plate electrode, the nanogenerators could provide a new way to power nanoscale devices without batteries or other external power sources.

The nanogenerators take advantage of the unique coupled piezoelectric and semiconducting properties of zinc oxide nanostructures, which produce small electrical charges when they are flexed. Fabrication begins with growing an array of vertically-aligned nanowires approximately a half-micron apart on gallium arsenide, sapphire or a flexible polymer substrate. A layer of zinc oxide is grown on top of substrate to collect the current. The researchers also fabricate silicon “zig-zag” electrodes, which contain thousands of nanometer-scale tips made conductive by a platinum coating.

This device could be a big step forward for self-powered nanotech devices and could help bring about the future of nano-machines.

Thursday, April 5, 2007

51 Things: Let Employees Work Close to Home

Number 13 on TIME Magazine's list of 51 Things We Can Do to fight global warming now is to let your employees work closer to home. Gene Mullins, a software developer in Seattle, created a program that helps firms slash the time employees spend driving by matching them with work closer to home.

By spending less time driving, employees use less fuel (and spend less time commuting). Using less fuel saves the employees some money and reduces the amount of pollutants going into the atmosphere.

Of course, an even better solution is to let employees work from home, and that's exactly what the Federal government is considering.

MIT Researchers Teach Computer to See Like a Person

A team of researchers at the Massachusetts Institute of Technology have created a computer visualization model that mimics the way humans see and interpret images. The computer model, designed to mimic the way the brain itself processes visual information, performs as well as humans do on rapid categorization tasks. The model even tends to make similar errors as humans, possibly because it so closely follows the organization of the brain’s visual system.

This new study supports a long–held hypothesis that rapid categorization happens without any feedback from cognitive or other areas of the brain. The results also indicate that the model can help neuroscientists make predictions and drive new experiments to explore brain mechanisms involved in human visual perception, cognition, and behavior. Deciphering the relative contribution of feed-forward and feedback processing may eventually help explain neuropsychological disorders such as autism and schizophrenia. The model also bridges the gap between the world of artificial intelligence (AI) and neuroscience because it may lead to better artificial vision systems and augmented sensory prostheses.

Importantly, the results showed no significant difference between humans and the model. Both had a similar pattern of performance, with well above 90% accuracy for the close views dropping to 74% for distant views. The 16% drop in performance for distant views represents a limitation of the one feed-forward sweep in dealing with clutter. Still, the researchers caustion that "We have not solved vision yet." With more time for cognitive feedback, people would outperform the model because they could focus attention on the target and ignore the clutter.

This model is a big step forward toward a real artificial intelligence (is that an oxymoron?). Computers that use a visual model to interpret what they are seeing could allow for computer systems that perform many of the tasks that are restricted to people today.

Wednesday, April 4, 2007

Mind-Machine Interface Takes a Step Forward

In a laboratory at the University of Southern California, a team of researchers has found a way to engineer a brain implant that can re-create thoughts, Popular Science reports. The revolutionary device could be used to treat brain damage or memory loss.

The chip represents a hardware version of the brain cells in your hippocampus that are crucial to the formation of memory. At the moment, the chip models fewer than 12,000 neurons, compared with the 100 billion or so present in a human brain. Still, even this small number represents a stunning achievement in the field of neuro-engineering.

The next big challenge, the researchers say, is to make the chip fully bidirectional, so that it can both generate and receive signals, just like a real cell.

For anyone (like me) who has a family history of memory loss (at least, I think I do... it's hard to remember...), a device like this could be just what the doctor ordered.

Tuesday, April 3, 2007

PTO Invalidates Three Human Stem Cell Patents

The U.S. Patent and Trademark Office has invalidated three patents covering human stem cells that were issued to the Wisconsin Alumni Research Foundation. This is good news for anyone who hopes to develop treatments for illnesses and injuries based on human stem cells, because the three patents have been blamed for slowing research in the highly visible field of regenerative medicine.

The PTO ruled the discovery of embryonic stem cells from primates--including humans--was not worthy of patent protection because scientists had used similar methods to isolate embryonic stem cells from mice and other mammals, and described the cells' potential for producing medical therapies.

It's too early to say for sure what affect this is going to have, because these results are still preliminary. WARF's attorneys have two months to respond to the concerns; if they don't succeed they can take the case to the Board of Patent Appeals and Interferences. If the patents are not reinstated, the foundation can file a claim in court.

When I hear more about the results of the legal proceedings, I'll post them here.

51 Things: Cozy Up to Your Water Heater

Number 21 on TIME Magazine's list of 51 Things We Can Do to fight global warming now is one of the simplest: wrap your water heater with a thermal blanket.

The cost? $10-20. The benefit? Your water heater will lose less heat over time, lowering your bill for electricity or gas (depending on your type of water heater), lowering your bills and your household carbon emissions (approximately 250 lbs. of CO2 per year).

For the price, I plan to do this for my apartment. There's not much I can think of that will have this much effect for such a small, one-time price.

Monday, April 2, 2007

Researchers Identify New Target for Blocking Cancer Cell Metastasis

Last week, the Van Andel Institute announced that its researchers have identified a protein involved in cancer cell metastasis, called DIP. DIP binds to and inhibits the activity of mDia2, a protein that works to control tumor cell metastasis, or the development of secondary tumors away from the primary cancer site.

When DIP binds to mDia2, it causes the affected cells to change shape and bubble, or bleb. This cell blebbing inhibits the control mDia2 has over tumor cell metastasis and may lead to development of secondary tumors.

If researchers can find a compound that will inhibit DIP, they believe it could prevent cancer cells from metastasizing, vastly improving the survivability of many forms of cancer.