Science, Technology & Health: November 2006 Archives

Here's a neat article about finding the mastermind in a social network... who do you have to eliminate to break the whole thing up? Who's got the real power in the group?

Who’s the most important player in a group? Who’s merely peripheral? Data crunchers find out by plotting people as “nodes” on computerized graphs, forming web-like networks. The links between nodes are then weighed and analyzed using matrix algebra and other tools.

And it's not the "hubs" who know everyone, as you might suspect. Social network analysis (SNA) is an emerging part of artificial intelligence, especially as we struggle to dismantle terrorist networks, and this stuff is pretty cutting edge.

Lots of people wonder what fire is made of, so read and find out.

The glow of a flame is somewhat complex. Black-body radiation is emitted from soot, gas, and fuel particles, though the soot particles are too small to behave like perfect blackbodies. There is also photon emission by de-excited atoms and molecules in the gases. Much of the radiation is emitted in the visible and infrared bands. The color depends on temperature for the black-body radiation, and chemical makeup for the emission spectra. The dominant color in a flame changes with temperature. The photo of the forest fire is an excellent example of this variation. Near the ground, where most burning is occurring, it is white, the hottest color possible for organic material in general, or yellow. Above the yellow region, the color changes to orange, which is somewhat cooler, then red, which is cooler still. Above the red region, combustion no longer occurs, and the uncombusted carbon particles are visible as black smoke.

So the flame itself consists of glowing, burning particles that rise due to convection and are called smoke and soot when they cool.

I don't know much about reading the weather because we didn't have much of it in Southern California. However, now that I'm in the middle of a blizzard in Missouri I guess it's time to learn.

I might just have to order this new book so I can understand my wife.

In The Female Mind, Dr Luan Brizendine says women devote more brain cells to talking than men.

And, if that wasn't enough, the simple act of talking triggers a flood of brain chemicals which give women a rush similar to that felt by heroin addicts when they get a high.

Dr Brizendine, a self-proclaimed feminist, says the differences can be traced back to the womb, where the sex hormone testosterone moulds the developing male brain.

The areas responsible for communication, emotion and memory are all pared back the unborn baby boy.

The result is that boys - and men - chat less than their female counterparts and struggle to express their emotions to the same extent.

"Women have an eight-lane superhighway for processing emotion, while men have a small country road," said Dr Brizendine, who runs a female "mood and hormone" clinic in San Francisco.

There are, however, advantages to being the strong, silent type. Dr Brizendine explains that testosterone also reduces the size of the section of the brain involved in hearing - allowing men to become "deaf" to the most logical of arguments put forward by their wives and girlfriends.

But what the male brain may lack in converstation and emotion, they more than make up with in their ability to think about sex.

Dr Brizendine says the brain's "sex processor" - the areas responsible for sexual thoughts - is twice as big as in men than in women, perhaps explaining why men are stereotyped as having sex on the mind.

Or, to put it another way, men have an international airport for dealing with thoughts about sex, "where women have an airfield nearby that lands small and private planes".

I knew it wasn't my fault, I'm just extremely masculine! Sweet.

Here's a great article that explores the oncoming intersection between artificial intelligence and human services. An important development, considering that there aren't nearly enough elder-care workers for the aging baby-boomers.

Unfortunately, there's a shortage of people working in nursing homes and caring for old people and the disabled, said Maja Mataric, director of the University of Southern California's Center for Robotics and Embedded Systems. The average stroke victim gets 39 minutes of active exercise a day when six hours a day is needed, she said, so robots can free up the few nurses for more nurturing activities.

Mataric adjusts her robots' personalities to fit the needs of stroke patients -- nurturing buddy or goal-pushing coach.

And in the case of low-functioning autistic children, they actually seem to relate better to robots than humans, Mataric said. "You'll see a child smile that has never smiled before. No one knows why it happens."

The scientists trying to engineer robots to work with humans are learning more than they expected. They have a new appreciation for our own unique abilities.

Said Deb Roy, director of MIT's Cognitive Machines Group: "It's not until you try to build a machine that does the same task (that people do) ... that you realize how incredibly hard it is."

I've said the same thing before. Studying artificial intelligence has given me a real appreciation of just how amazing humans are.

I like this quote:

"We're cheap dates," [Sherry Turkle from MIT] says. "If an entity makes eye contact with you, if an entity reaches toward you in friendship, we believe there is somebody there ... But that doesn't mean that there is. That just means that our Darwinian buttons are being pushed."

Despite all the amazing scientific advances of the past few centuries there is still a heck of a lot that we don't know, especially about ourselves. First up is a really remarkable new study that has completely revolutionized our understanding of genetics.

The discovery has astonished scientists studying the human genome - the genetic recipe of man. Until now it was believed the variation between people was due largely to differences in the sequences of the individual " letters" of the genome.

It now appears much of the variation is explained instead by people having multiple copies of some key genes that make up the human genome.

Until now it was assumed that the human genome, or "book of life", is largely the same for everyone, save for a few spelling differences in some of the words. Instead, the findings suggest that the book contains entire sentences, paragraphs or even whole pages that are repeated any number of times.

The findings mean that instead of humanity being 99.9 per cent identical, as previously believed, we are at least 10 times more different between one another than once thought - which could explain why some people are prone to serious diseases.

One consequence that the article underplays is that this discovery now makes it possible, for the first time, to determine a person's "race" or "ethnicity" based on their DNA. What's more,

Another implication of the finding is that we are more different to our closest living relative, the chimpanzee, than previously assumed from earlier studies. Instead of being 99 per cent similar, we are more likely to be about 96 per cent similar.

Thereby striking another blow against evolution (which will probably go completely unnoticed until the entire edifice crumbles). As I said, there's a lot we don't know, and it's continually surprising how much of what we think we know turns out to be wrong or only partially right. Makes life interesting!

Secondly, some high-definition pictures of animals in the womb.

An unborn elephant, tiny but perfect in every way. A dolphin swimming in the womb, just as it will have to swim in the ocean the moment it is born. An unborn dog panting. Each one amazing and now, thanks to these remarkable pictures, they can be seen for the first time.

Using an array of technology, the images reveal what until now has been a secret - exactly how animals develop in the womb. They were created by the same team who in 2004 showed how human embryos "walk in the womb".

Using a combination of three-dimensional ultrasound scans, computer graphics and tiny cameras, the team were able to show the entire process from conception to birth.

"These kind of images from inside animals have never been seen before," said Jeremy Dear of Pioneer Productions, who made the film.

These sorts of pictures will eventually overcome the ocean of blood money that keeps the abortion industry afloat.

"Animals were trained to sit still near the scanners and we also inserted cameras into the womb via the elephant's rectum-But it has been worth it. It one sequence we follow an elephant developing. When it is finally born, there is not a dry eye in the house.

Wait for the same movie to be made of a human baby. The whole debate on abortion is undergoing a sea-change as our scientific knowledge of what goes on in the womb advances. Those of our children who survive will likely live in a world that recognizes abortion as the barbarity it is.

Update:

I like James Taranto's take on the in utero pictures:

The unborn elephant, shown at the link, is quite something to see. By contrast, as we all know from reading the newspapers, there is no such thing as an unborn human being. We develop by a little-understood process in which a clump of cells, similar to a tumor or a fingernail, miraculously becomes a baby at the moment the entire clump is exposed to air.

That humans and animals come into the world in such radically different ways pretty much demolishes the notion that we are the product of Darwinian evolution, doesn't it?

Finally! A use for all that corn starch in my pantry...

Jesus: No comment.

(HT: GeekPress.)

My brother sent me a fascinating article about "cloud computing" at Google et al. that relates a lot of nifty inside-ish info on the man behind the curtain... and he really is a wizard. The most interesting part to me, though, was about power consumption.

If it's necessary to waste memory and bandwidth to dominate the petascale era, gorging on energy is an inescapable cost of doing business. Ask.com operations VP Dayne Sampson estimates that the five leading search companies together have some 2 million servers, each shedding 300 watts of heat annually, a total of 600 megawatts. These are linked to hard drives that dissipate perhaps another gigawatt. Fifty percent again as much power is required to cool this searing heat, for a total of 2.4 gigawatts. With a third of the incoming power already lost to the grid's inefficiencies, and half of what's left lost to power supplies, transformers, and converters, the total of electricity consumed by major search engines in 2006 approaches 5 gigawatts.

That's an impressive quantity of electricity. Five gigawatts is almost enough to power the Las Vegas metropolitan area – with all its hotels, casinos, restaurants, and convention centers – on the hottest day of the year. So the annual operation of the world's petascale search machines constitutes a Vegas-sized power sump. In the next year or so, it could add a dog-day Atlantic City. Air-conditioning will be the prime cost and conundrum of the petascale era. As energy analysts Peter Huber and Mark Mills projected in 1999, the planetary machine is on track to be consuming half of all the world's output of electricity by the end of this decade.

Google's Hölzle noticed the high electric bills after taking his post in 1999. At 15 cents per kilowatt-hour, power dominated his calculus of costs. "A power company could give away PCs and make a substantial profit selling power," he says. (At The Dalles, the huge protuberances on top are not giant disk drives, climbing to the rooftop for a smoke while the RAM below does the work, but an array of eight hulking cooling towers.)

The struggle to find an adequate supply of electricity explains the curious emptiness that afflicts some 30 percent of Ask.com's square footage. Why is the second-fastest-growing search engine one-third empty? "We ran out of power before we ran out of space," says search operations manager James Snow, a ponytailed refugee from an IBM acquisition. Not only does the Verizon facility lack a cheap power source, it struggles to get any further power at all; designed for the more modest needs of Internet switching, the building has already maxed out the local grid. Consequently, Ask.com's Sampson has followed Google's trail to the Columbia River, where he's scoping out properties. Perhaps by moving farther up the river into the Washington headwaters he can get even cheaper power than Google will get in The Dalles.

Maybe they should build a datacenter on Mercury? There should be plenty of heavy metals readily available on the surface, and it's located down the sun's gravity well so it's easier to reach than Mars.

Update:

Bernardo says I'm behind the times and that Google is already planning to conquer the moon.

Reader JV passed me a link to Microsoft's amazing Photosynth technology, and I'm practically speechless. The video below shows how it works, and how it can be used.

The possible uses for this technology are endless and almost incomprehensible, especially when combined with a tool like Google Earth (or Microsoft's other Live software).

Although free, universal healthcare sounds alluring, remember that nothing is free and that nationalized healthcare isn't all it's cracked up to be.

Men are having to fight 'titanic battles' for access to tried and tested treatments for prostate cancer, a charity chief said today.

John Neate, chief executive of The Prostate Cancer Charity criticised a "short-sighted and devalued" NHS, which was compromising the care of prostate cancer patients. ...

Mr Neate said: "It cannot be acceptable that men and their families who are already having to deal with the tough news of a prostate cancer diagnosis have to wrestle with NHS bureaucracy at the same time."

The government can barely handle national defense, why would anyone trust them to care for our health?

Despite internet rumors and its membership in the triad of necessary and sufficient tools, it appears that duct tape can't cure warts.

Duct tape does not work any better than doing nothing to cure warts in schoolchildren, Dutch researchers reported on Monday in a study that contradicts a popular theory about an easy way to get rid of the unattractive lumps.

The study of 103 children aged 4 to 12 showed the duct tape worked only slightly better than using a corn pad, a sticky cushion that does not actually touch the wart and which was considered to be a placebo.

"After 6 weeks, the warts of 8 children (16 percent) in the duct tape group and the warts of 3 children (6 percent) in the placebo group had disappeared," the researchers wrote in the Archives of Pediatrics and Adolescent Medicine.

They said this difference was not statistically significant.

However, extensive studies have proven that duct tape can cure baldness.

(HT: TheDailySpork.)

In Los Angeles we didn't have to worry about such things, but here in Missouri I've had to quickly learn about wind chill and the heat index. No one had ever been able to give me a concrete definition of either term, so I turned to the ever-reliable Wikipedia for answers.

Wind chill is the apparent temperature felt on exposed skin due to the combination of air temperature and wind speed. Except at higher temperatures, where wind chill is considered less important, the wind chill temperature (often incorrectly called the "wind chill factor") is always lower than the air temperature, because any wind increases the rate at which moisture evaporates from the skin and carries heat away from the body. The phase change of water (in sweat) from liquid to vapor requires that the molecules reach a higher energy state. That energy is acquired by absorbing heat from surrounding tissue by conduction (see heat transfer).

Because wind chill is related to evaporation, dry inanimate objects are not affected by wind chill the way humans and animals are. Wind chill won't have much effect on your car, house, or outdoor machinery.

Similarly, the heat index is a measure of how much the ambient humidity is affecting evaporation.

The Heat index (HI) is an index that combines air temperature and relative humidity to determine an apparent temperature — how hot it actually feels. The human body normally cools itself by perspiration, or sweating, in which the water in the sweat evaporates and carries heat away from the body. However, when the relative humidity is high, the evaporation rate of water is reduced. This means heat is removed from the body at a lower rate, causing it to retain more heat than it would in dry air. Measurements have been taken based on subjective descriptions of how hot subjects feel for a given temperature and humidity, allowing an index to be made which corresponds a temperature and humidity combination to a higher temperature in dry air.

Humid air slows the evaporation of sweat and thereby reduces our ability to cool ourselves. Simple enough! Both pages have common formulas for calculating these values, if you're feeling adventurous.

NASA has an interesting high-level description of potential interstellar propulsion technologies based on current science. They aren't as cool as Star Trek warp drives, but at least they're somewhat based in reality. The Project Orion concept is my favorite.

Stanislaw Ulam realized that nuclear explosions could not yet be realistically contained in a combustion chamber. Such a project did briefly exist, named Helios, but its theoretical performance was so poor that it never got beyond the drawing board.

Instead, the Orion design would have worked by dropping fission or thermonuclear explosives out the rear of a vehicle, detonating them 200 feet (60 m) out, and catching the blast with a thick steel or aluminum pusher plate.

Large multi-story high shock absorbers (pneumatic springs) were to have absorbed the impulse from the plasma wave as it hit the pusher plate, spreading the millisecond shock wave over several seconds and thus giving an acceptable ride. The long arm pistons proved one of the most difficult design features but many members of the team said that this seemed solvable. Low pressure gas bags were also used for a primary shock absorber. The two sets of shock absorption systems were tuned to different frequencies to avoid resonance.

One aspect of the proposed vessel seems counter-intuitive today; because of the force involved in the thermonuclear detonations and the need to absorb the energy without harm, large, massive vessel designs were actually more efficient. Early designs had crew compartments and storage areas that were several stories tall, as opposed to contemporary chemical rockets whose height was almost all multi-stage fuel tanks with relatively little payload.

Here's more on spacecraft propulsion.