Bacterial Enzyme Releases Hydrogen
Optimists who say we can quickly switch from a fossil fuel economy to a hydrogen-powered economy face an elephant in the room they'd rather not see: the huge cost of creating hydrogen gas. Now chemists at Oxford University in the UK think they have a solution. While researching enzymes that are used by organisms to convert hydrogen ions into hydrogen gas, they discovered one bacterial enzyme with properties that make it admirably suited to generating hydrogen from water.
The main problem with such enzymes, called hydrogenases, is that they do their best work in the absence of oxygen, and are also damaged to a greater or lesser extent by the hydrogen they produce. The enzyme utilized by chemists Erwin Reisner and Fraser Armstrong is rich in nickel, iron and selenium. It is hardly affected by hydrogen gas, and can function in air that contains one percent oxygen by volume ? which is quite an improvement over hydrogenases that normally can't handle even a few parts per million of oxygen.
Reisner and Armstrong note that the enzyme binds to titanium dioxide nanoparticles, and works in the presence of light. This results in a sort of light-powered, hydrogen-generating dust. So far, the process is slow; when one small sample spent eight hours under a lamp, the gas above it became 4.6 percent hydrogen by volume. Still, it produced much more hydrogen than the control experiment, and Armstrong felt it was ?promising for a first trial.? It could be one small step toward a hydrogen-based economy. The next steps would include improving the efficiency of the reaction and releasing the oxygen from the water as well as the hydrogen. Other researchers think they can use such hydrogenases in the design of an inexpensive catalyst that is unaffected by oxygen.
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Imagine MRI With 100 Million Times the Resolution
Magnetic resonance imaging (MRI) was a huge breakthrough and remains a vital medical test for diagnosing many ailments. But even this technology has its limits. Now IBM Research scientists, in collaboration with the Center for Probing the Nanoscale at Stanford University, have stretched those limits to an almost unimaginable degree. They have demonstrated MRI imaging that can resolve details 100 million times finer than conventional MRI.
The ability to see such fine details means that very tiny, complex three-dimensional structures that could not be examined directly before can now be seen. The scientists hope their research will lead to a microscope that can reveal the structure and interactions of individual proteins. Such a research tool could lead to the ability to create more targeted and individualized medicines.
To achieve this massive increase in imaging resolution, the scientists used a technique called magnetic resonance force microscopy (MRFM), which detects the tiniest magnetic forces. The technique has a number of advantages, not the least of which is that it does not damage biological materials. It's unlikely that we'll see this new MRI technique used on patients the way conventional MRI is, but "This technology stands to revolutionize the way we look at viruses, bacteria, proteins, and other biological elements," notes IBM Fellow Mark Dean, vice president of strategy and operations for IBM Research.
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Internet Relatively Safe for Kids After All
Parents worry about millions of threatening things when it comes to their children, but a report newly released by a task force made up of 49 state attorneys general discovered that at least one of those threats was overblown. According to the Internet Safety Technical Task Force, the panel putting together the report, the Internet isn't as dangerous for children as depictions in the media make it out to be.
The task force focused on the extent of the threats that children face on MySpace, Facebook and other social networks. They were specifically concerned that adult sexual predators were using these networks to mislead and harm vulnerable children. But apparently the task force found very little of this activity. John Cardillo, CEO of a company that maintains a sexual offender database, and a member of the task force, noted that ?Social networks are very much like real-world communities that are comprised mostly of good people who are there for the right reasons.?
So does that mean that parents can breathe easy while their children spend time on MySpace? Not quite. The task force found that the biggest threat facing children, much worse than that of sexual predators, is the problem of online and offline bullying among children. Lest you think that this is a flip conclusion, you can examine the 278-page report for yourself; it was a year in the making, and came out of meetings between ?dozens of academics, experts in childhood safety and executives of 30 companies, including Yahoo, AOL, MySpace and Facebook,? according to the New York Times.
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