MUSIC: "Our World" theme

This week on "Our World" ... The strongest tropical cyclones are getting stronger ... Exercise may slow Alzheimer's memory loss  ... and NASA gets ready to fix a remarkable earth-orbiting telescope ...

GRUNSFELD:  "The Hubble Space Telescope is more than remarkable. ... It's answered just so many of those fundamental questions that people have been asking about the cosmos since people were able to ask questions."

Those stories, Google's new web browser, and more. I'm Art Chimes. Welcome to VOA's science and technology magazine, "Our World."

Strongest storms have been getting stronger

Some of the most powerful storms on earth are getting stronger, according to new research published this week.

ELSNER:  "If we look at over the entire globe, we see that the strongest tropical cyclones are actually getting stronger. And this increase is most notable over the North Atlantic and also the northern Indian Oceans."

Jim Elsner of Florida State University and his colleagues based their conclusion on 25 years of satellite data.

They found that the top wind speeds in the strongest tropical cyclones have been increasing. And the stronger the cyclone, the bigger the increase.

Scientists say these storms pick up energy from the warm water they pass over. Elsner says that's really a simplified version of what's happening.

ELSNER:  "And this thermodynamic theory of hurricane intensification says that, with all else being equal, the warmer the ocean, the stronger the storms. So it stands to reason that if the theory is correct we should see increases in the intensity of the strongest storms with the warming ocean."

And that's exactly what they saw. For their study, Elsner and his colleagues examined the top wind speed in a range of storms, from weak to strong.

The weaker storms showed little or no increase in their maximum wind speed over 25 years of observations. But in the same period, the top wind speed in the strongest storms rose significantly.

ELSNER:  "Generally the wind speed and how much power, destructive power a hurricane has are very well correlated."

Incidentally, although the storm data comes from satellites, Elsner says satellite instruments don't measure the wind speed directly.

ELSNER:  "But what you can do is look at how the pattern of the satellite pictures are changing over time. If you see how the clouds change from one picture to the next, you can get some idea of motion. So if you look at where the clouds were at one time, then later, you get some idea of speed."

The effect the researchers observed was not evenly distributed around the world, probably because of different conditions in the various areas where tropical cyclones occur.

ELSNER:  "Well, we speculate that has to do with the amount of warming we're seeing in the different basins. So basins that are marginally warm enough to support tropical cyclones on average and are increasing, then we expect to see the effect stronger in those basins, and those include the North Atlantic and Indian Oceans."

So is this effect related to climate change? Elsner says his study looked at data from the past quarter-century, so he says it can't necessarily predict what's in the future. But warmer oceans could provide the energy to fuel stronger storms, and he said the data is consistent with the idea that global warming could affect sea temperatures.

ELSNER:  "That gives us some confidence that if the seas continue to warm, we're likely to see the stronger storms getting stronger."

Jim Elsner of Florida State University. His paper appears this week in the journal Nature. 


Exercise program helps stroke victims

Next, two stories about how exercise can help people who are ill.

Strokes are caused when something disrupts the brain's supply of blood ? along with the oxygen it carries. When this happens, the stroke victim is often left disabled. As we hear from health reporter Rose Hoban, new research indicates it may be possible to reverse some of the effects of a stroke.

HOBAN:  For many years, doctors believed that this kind of disability was irreversible.

But in the past few years, researchers have been testing ways to help stroke patients regain movement and strength. Dr. Andy Luft and a team from the Johns Hopkins University in Baltimore worked with patients from a local Veterans' Affairs Hospital. They gave half of them an intensive exercise regimen.

LUFT:  "We were training them in the VA hospital on a treadmill program for six months, which is three times a week for about an hour. And then we studied them before and after the six-month training program and we assessed walking and cardio respiratory fitness." 

HOBAN:  Luft and his colleagues found that the treadmill patients were able to walk faster than another of group of patients who only did stretching exercises. They also had better heart and lung function after the training.

The researchers also put the patients who were getting treadmill training into a brain scanner, and had them move their legs as if they were walking.

LUFT:  "And that will show you all the brain areas involved in this movement, and likely involved in walking. And then we compared before and after training and sought changes reflecting what we called plasticity in the brain. So, a reprogramming of these brain circuits that control walking. And that's what we're after." 

HOBAN:  Luft says they're not sure exactly how this brain 'rewiring' takes place. He says it might be that the brain taps into some very primitive areas during the retraining process.

LUFT:  "Through this training after stroke, these evolutionary old regions are reactivated and may be able to compensate."

HOBAN:  Luft says the retraining has to be very intense in order to be effective. But he says it opens up the possibility that people might be able to regain abilities after losing them to stroke.

Luft's research is published in Stroke: Journal of the American Heart Association. I'm Rose Hoban.


Exercise may help Alzheimer's patients, too

Another study indicates that people with Alzheimer's Disease may also benefit from exercise.

Alzheimer's is the crippling brain disease that causes memory loss and other problems, mainly among the elderly.

As VOA's Jessica Berman reports, there are some promising findings from a small study of older men and women in Australia

BERMAN:  Experts say the number of people afflicted with Alzheimer's will quadruple by the middle of the century because people around the globe are living longer and Alzheimer's tends to strike older individuals.

But a new study suggests that the dementia that is a hallmark of the disease could be delayed among patients who exercise moderately three times per week.

Researchers at the University of Western Australia conducted a study involving 138 adult men and women, aged 50 and over, that had memory problems but not dementia.

The participants were randomly assigned to a moderate intensity exercise program for six months. Researchers had them exercise an average of 50 minutes three times per week. Most of them walked. The other group was educated about exercise, but was not encouraged to do so.

At the end of the study, those in the regular exercise group did better on cognitive tests to assess their memory, according to Nicola Lautenschlager, a psychiatrist who specializes in the elderly.

LAUTENSCHLAGER:  "What we do not know at this point of time is the mechanism underlying this effect."

Researchers found the benefit was small, with a modest improvement on the cognition scale. But Lautenschlager says the study showed that exercise is more effective than medication, which has little or no effect at improving mild memory loss.

Lautenschlager is sufficiently encouraged that she says doctors may change their advice to patients with Alzheimer's disease.

LAUTENSCHLAGER:  ""We need to reconsider what we recommend to older people when they ask us what kind of healthy lifestyle do I need to do to protect my brain."

The study on the benefits of exercise in delaying the dementia in Alzheimer's disease is published in the Journal of the American Medical Association. Jessica Berman, VOA News, Washington.


Environmental news on our Website of the Week

Time again for our Website of the Week, when we showcase interesting and innovative online destinations.

This week it's a way to get all your environmental news in one convenient place.

NORTON:  "The trend is that sustainability and environmental news is going to be ever-growing, and we want to make sure that we cover everything."

Lawrence Norton is publisher of the Environmental News Network at

NORTON:  "Environmental News Network likes to think that we are a broad but relatively deep news network. So we try and cover as many topics as possible. Some of those could include science and technology breakthroughs or environmental health."

Norton says ENN collects stories from trusted sources, including news agencies and environmental newsletters.

NORTON:  "We have an affiliate network of people who submit stories to us, about 35 partners. And basically, ENN publishes their stories through our website, as well as commentary and bloggers from around the world, actually."

Top stories appear on the home page, of course, and to help you explore more environmental news, it's all sorted under categories such as wildlife, ecosystems, climate, and green building. aggregates news, but it also distributes news in the form of press releases by a wide range of organizations involved with the environment.

NORTON:  "So we work with over 200 nonprofits to get these stories out and around. You'll see all of these announcements from our press members. And some of those stories, I think, are sometimes even more interesting that what you can find above the fold."

The Environmental News Network. Read all about it at, or get the link to this and more than 200 other Websites of the Week from our site,


MUSIC:  "Speed House"


You're listening to VOA's science and technology magazine, Our World. I'm Art Chimes in Washington. 

Google introduces Chrome web browser

Google, the Internet search company, turns ten years old this weekend.  It was incorporated on September 7, 1998, by two 24-year old Stanford University students, Sergey Brin and Larry Page, who today are still at the helm of what is now a publicly-traded company worth more than $150 billion.

Google in the past decade has expanded into several other Internet applications, including a global map program, an e-mail service and an online word-processor. This week, Google introduced a new web browser called Chrome. It competes with the market leader, Microsoft Internet Explorer, the popular open source Firefox browser, and Apple's Safari for Macintosh users.

To find out more, we checked in with Rafe Needleman, editor of CNET's, where he writes about "cool web apps for everyone." He was at Google's press event on Tuesday and has been testing out Chrome for himself. 

NEEDLEMAN:  "Well, it's fast. Chrome is based on a rendering engine, the engine underneath it, there are two parts, one of which makes web pages load pretty fast, and the other one, called V8, works on Javascript. Now Javascript is the language that most of the new interactive web pages are written in, like Google's Gmail or maps or stuff like that. And it's much faster than the current Javascript implementation. So this means that advanced, interactive web pages, web applications, should work more quickly in Chrome than other products."

Q:  You know, I like to think of the three s's in terms of browser usability: speed, you just addressed, but [also] stability and security. How does Chrome stack up in those departments?

NEEDLEMAN:  "We've done some early tests and we've determined that it is, in fact, faster. In terms of stability there's a very key element of Chrome, which is that each tab is a separate process, which means if you go to a web application that crashes, it will only crash that tab. It won't bring the whole browser down around it."

Q:  What about the user interface itself?  There's no separate search box, for example. From the user's point of view, how does the interface differ?

NEEDLEMAN:  "Yeah, it does mirror the Google aesthetic, which is definitely spare. There is no menu bar. And for a Google product, there is no search box. How funny is that? What they have is something ? the address bar they call the Omnibox. When you type in the web address of a place you've been to before, it fills it in for you automatically. You just press enter to go there. If you type in something that is a search query that is not an Internet domain, it fires off the search. The home page for Chrome is a really useful thumbnail view of the sites that you go to most often and most frequently, along with a list of search engines you use and recent things added to your bookmarks.

"I'm not sure I would recommend that people jump over today. Not all websites render perfectly in Google. It is, after all, still a beta of a 1.0 product. But it does show kind of the direction of where things are going."

Q: You mentioned that this is a beta, and Google does seem to love beta versions, but what's missing from Chrome. Obviously there's a development roadmap still ahead?

NEEDLEMAN:  "There are a few key things still missing from Chrome. For example, if you are a Macintosh or a Linux user, there is no Chrome for you. Google says, our developers are Mac users. They want it as much as we do. So they're working on it.

"Now, another key thing that's missing that Firefox has made a lot of hay with is an architecture for extensions. Those are the things that you add into Firefox to do things that it doesn't do inherently out of the box. Again, Google says it's on the roadmap and they'll layer it in as soon as it's ready, but it's not there today.

Q: Why is Google doing this? What's in it for Google to have a browser of their own out there?

NEEDLEMAN:  "That is the million dollar, or in Google's case the $40 billion question. The more people who use the Internet, the better it is for Google because Google makes a lot of money from advertising queries and search queries on the web. And what this platform does ? and this is a platform, not just a browser ? more designed for web applications as opposed to just web pages - the more Google can encourage people to write complex and rich web applications, the less they need the traditional operating system.

"As programmers start to write applications that run well on Google [Chrome], the other browsers, Google hopes, will have to scramble to keep up.  So even if people don't use Google's Chrome and the other browsers get better and people continue to use the other browsers, they're still using browsers, they're still using the Internet. Google still profits."

Rafe Needleman, editor of He also said that at this week's news conference, Google officials made a big deal of the fact that it's being released in more than 40 languages, including Mandarin, Arabic, and Hindi, as well as most European languages.


Astronauts preparing for Hubble Telescope repairs

In just over a month [Oct 8], the space shuttle Atlantis will blast off from Florida, heading not for the International Space Station, its usual destination, but for the earth-orbiting Hubble Space Telescope.

Astronauts will maneuver the bus-sized telescope into the shuttle's cargo bay, then perform a series of space walks to install new science instruments, replace batteries and gyroscopes, and generally do what's needed to keep Hubble in good shape until its replacement is launched, five years from now.

Astronaut Mike Massimino will be on two of the five space walks.

MASSIMINO:  "We're going up to Hubble and we're going to put in a new Wide Field Camera, which is going to increase the telescope's ability to see into the universe by a factor of 10, so we can see a lot of cool stuff if we do our job right and this thing works. So we're excited about the Wide Field Camera, and also the Cosmic Origins Spectrograph, which is another big scientific instrument we're putting in. So those things are going to increase the science capability of the telescope."

Massimino was on one of the previous Hubble servicing missions. His crewmate, John Grunsfeld, was on three of the four prior Hubble repair flights.

GRUNSFELD:  "The Hubble has been in orbit for 18 years. It's a remarkable period of time for any spacecraft to be operating at the level Hubble has, and in an environment that's pretty nasty, and that takes its toll on the telescope."

Grunsfeld's academic background is in physics and astronomy. He says it's important to keep Hubble working as long as possible because of the contributions it's made to science.

GRUNSFELD:  "The Hubble Space Telescope is more than remarkable. It has produced all of the science that we expected it would ? the discovery that black holes really do exist, massive black holes millions of times the mass of our sun. It's measured the age of the universe. It's answered just so many of those fundamental questions that people have been asking about the cosmos since people have been able to ask questions."

After the shuttle program's second fatal accident in 2003, NASA cancelled the planned repair mission to Hubble. Astronomers and other supporters of the space telescope urged the decision be reversed, but NASA considered the flight too dangerous. If there were any problem with the shuttle, they said, the astronauts would be stranded. Space flight is inherently dangerous, so NASA now includes extensive inspections of the shuttle in orbit. And crew commander Scott Altman explains what happens if they find a problem.

ALTMAN:  "So we will shelter in place on our [shuttle] orbiter, power down to extend the life, the oxygen, and we can go up to roughly 25 days waiting for somebody to come up to us. Meanwhile, NASA's decided to have an orbiter on the pad so the day we launch, that if we find damage flight day 2 or flight day 3, turn that mission on, and by our flight day 7 or so, they're airborne, coming up after us."

The 11-day shuttle flight to the Hubble Space Telescope is set to begin October 10.


Major test for world's largest physics experiment

The biggest science experiment on Earth is expected to take a big step forward on Wednesday.

Scientists at the European Organizatio