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Do you know where you came from?

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Genetic test nowadays are dirt cheap. And your 23 chromosomes have amazing stories to tell, including details of your ancestry. In fact, white supremacist were quick to jump on the gene sequencing process to prove their "ethnic purity" only to find out that they weren’t all that pure after all. They were particularly disturbed to learn that all our distant ancestors were from Africa and we all were black! But I'm getting ahead of the story.

As you know, our 23 pairs of chromosomes are made of DNA, and everyone inherits half of their DNA from their mother and half from their father. 



When DNA is passed from parents to their children, the two chromosomes in each pair are randomly shuffled together. What you may not know is that when the chromosomes are shuffled, long segments from a single recent ancestor are broken into shorter segments. In the next generation the grandparent's segments are reshuffled and their fragments become shorter yet, and sometimes just disappear.…

Fun with RADAR

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Say 'radar' and most people think of FAA air traffic controllers following airplanes or NASA engineers tracking rockets. But RAdio Detection And Ranging can be used for a lot of purposes including some that are simply fun. Especially when you can put a whole radar system on a 5mm x 5mm chip, like ViaSat managed to do.

If you stand in a canyon and yell, you'll hear an echo when the sound of your voice bounces off the side of the canyon and back to you. Like timing a thunder clap to judge distance to lightning, if you time the echo of your yell and know the speed of sound (roughly a 1000 feet per second) you can estimate how far away the cliffs are (and how close a thunderstorm is).

With radar you essentially do the same thing except you use a radio signal instead of sound, and the signal propagates at almost the speed of light (about 11 inches per nanosecond). Send a radio pulse, listen carefully for an echo, and you can tell how far away something is by measuring how long…

Satellite Solutions

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Technology is always in the news these days, but there's one spectacular device out there you've probably never heard of.

ViaSat-1, launched in late 2011, provides more capacity in one satellite than all other communications satellites over North America combined. It will help 1,000,000 technologically deprived web surfers on the ground, in the air, and on the high seas join the 21st Century.

If you rummage around online forums about broadband services you'll find grumps who complain that satellite services can be interrupted by something as common as rain. That used to be true, but engineers have found a solution so the ViaSat Exede service will do just that— exceed your expectations. Now it's just silly to worry about weather effects except under the most extreme circumstances.

Jim Petranovich, MIT grad and Chief Geek at ViaSat subsidiary Enerdyne, wrote a technical  whitepaper that discusses the ways ViaSat reduces and prevents the affects of weather for users of th…

Robot Wars

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Our robot took its first steps today. Now there's a line I never thought I'd write. I read more science fiction than most people, I suspect, but somehow I never really thought I'd own a robot. But I do.

Come to think of it, this baby is our second. Several years ago we bought an iRobot Roomba.


Rommba sucks, but that's a good thing for a vacuum cleaner. In fact, it works very well indeed, and while initially we thought it was kinda expensive, it definitely has earned its keep, wandering around nibbling odds and ends and scarfing down cat hair. When it gets caught under the sofa it bleats, "Oh-oh" a few times, and then patiently goes to sleep until we rescue it. Free to roam, it even heads home to find its docking station when the battery runs low and it needs to literally recharge its batteries.

But the second little bundle of joy came into out lives when my son, in a geneologically confusing sorta way, gave us a brother for Roomba—iRobot Create. We call him V…

Zero G Isn't Gravity free

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Watch a Space Shuttle launch and you'll hear about "zero gravity" and "zero G", terms that make people think (incorrectly) that someone or something in orbit has somehow escaped Earth's gravity. Not so. Without gravity you couldn't put a spacecraft in orbit. Imagine hitting a baseball across a ballfield. Picture the arc it makes as it goes off into the outfield. To hit a home run, you have to hit it higher, and harder,  to make a bigger arc that takes it out over the fence.
Now imagine launching the ball using a catapult, a cannon, and finally a rocket. As you send it with more force, the ball arcs out higher and faster, and lands farther and farther away--across the street, out of the neighborhood, over your town, across your country, even across the nearest ocean.
Eventually, if you launch it high enough and hard enough it will sail right over the distant curving edge of the earth itself. Instead of coming down, it literally misses the surface, gravity p…

What Doesn't Kill Us Makes Us Stronger?

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Philosopher Friedrich Nietzsche, in Twilight of the Idols (1888) wrote "What does not destroy me, makes me stronger." But modern research by the Naval Health Research Center shows that's not the case. If you've been assaulted, you're twice as likely to suffer from post traumatic stress syndrome.



Data on exposures and health outcomes were collected as part of the Millennium Cohort Study. Of 55,000 participants, data was anaylzed from from 5324 (881 women and 4443 men) who were in combat in Iraq and Afghanistan and had no Post-traumatic Stress Syndrome (PTSD) symptoms before they went.

As reported in the journal Epidemiology, more than twice as many man and women who had been assaulted prior to entering combat suffered from PTSD afterwards than those who had never been assaulted.
In other words, the odds of new-onset PTSD symptoms was more than 2-fold higher in both women and men who reported assault prior to deployment.

Alcohol Abuse Is No Laughing Matter

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The returning vet who's become a drunk is a recurring, if sad, stereotype. But until recently there wasn't much data on the problem.
Late last year the Naval Health Research Center published a report in the Journal of the American Medical Association that shows the problem is not a myth.

Data from the Millennium Cohort Study showed that Reserve and National Guard personnel and younger service members who deploy with reported combat exposures are, in fact, at increased risk of new-onset heavy weekly drinking, binge drinking, and alcohol-related problems.

Smoke If Ya Got 'Em

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The old black and white war movie admonition to, "smoke if ya got 'em" isn't just a cliche.

American Journal of Preventive Medicine conducted by the Naval Health Research Center in San Diego found that among people who had never smoked, almost twice as many service members sent overseas were likely to start smoking than those who stayed home.

Among those who used to smoke almost half again as many returned to smoking if they were deployed as those who didn't, and those who saw combat were 1.6 times more likely to start smoking than non-smokers. Those who were deployed for more than 9 months and those who deployed multiple times were more likely to start smoking again too, although it didn't seem to affect how much they smoked.

Want To Lose Weight? Go to war!

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There are probably easier ways to diet, but women who have seen combat in Iraq or Afghanistan are more than twice as likely to lose 10% or more of their body weight than those who were deployed but didn't see combat. Unfortunately, those who saw combat were almost twice as likely to develop an eating disorder.
The Naval Health Research Center (NHRC) in San Diego recently published these findings in the American Journal of Epidemiology based on data collected as part of a fascinating long term study called the Millennium Cohort Study.
Going overseas didn't seem to stimulate eating disorders in either women or men, but combat did.
Another interesting finding from the data is that low mental or physical health status before combat exposure significantly increases the risk of symptoms or diagnosis of post-traumatic stress disorder (PTSD) after deployment.
Now that we know that, thanks to the Navy's research, more vulnerable service members can be identified and provided training …

Bug 1, Bird 0

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Man bites dog is a newsworthy event, they say, but not dog bites man. In the same sense, bird eats bug, wouldn't be worthy of a headline. But how 'bout bug bites bird, or better yet bug eats bird?

That's exactly what happened recently, and my sister and brother-in-law caught it on this video.



Patiently becoming a part of the feeder, this preying mantis caught a naïve hummingbird, and within a minute the prey's struggle was over. This amateur video and pictures were taken over a few summer mornings in Albuquerque, NM.
I never thought of Preying Mantids as carniverous or quick, but they're obviously both.
More on hummingbirds here.

• Galaxy Springs a Leak

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This interacting group contains several galaxies along with a "cosmic fountain" of stars, gas and dust that stretches over 100 000 light years.


Over the past 19 years Hubble has taken dozens of exotic pictures of galaxies going "bump in the night" as they collide with each other and have a variety of close encounters of the galactic kind. Just when you thought these interactions couldn’t look any stranger, this image of a trio of galaxies, called Arp 194, looks as if of the galaxies has sprung a leak. The bright blue streamer is really a stretched spiral arm full of newborn blue stars. This typically happens when two galaxies interact and tug at each other gravitationally.

Resembling a pair of owl's eyes, the two nuclei of the colliding galaxies can be seen in the process of merging at the upper left. The bizarre blue bridge of material extending out from the northern component looks as if it connects to a third galaxy but in reality this galaxy is in the backgro…

• Fox & Friends Undress For Success

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In bed by 7 last night, lights off by 8. Kate promptly fell fast asleep, and I went into that aggravating half-awake-half-asleep-waiting-for-the-alarm-to-ring-never-never-land. We both woke up at 11:45 for some reason, but fell back to sleep until the alarm went off at 1:45am.

Coffee and shower, hurried last minute review of notes, and the limo arrived at 2:45. Not much talk in the car, re-read notes wondering what to expect. Asked the driver if this was the main Fox station or was there another downtown. He said where we were going was a contract video studio used for remotes, basically just a room and a camera. And that's what it was.


You'd recognize the camera man instantly. He was the geeky kid that belonged to the AV club in high school and ran the projector when there was a movie in class, just older.

The backdrop, instead of a paper graphic, was huge digital display running a video of the San Diego harbor in broad daylight, of course, not zero dark thirty blackness. Talked…

• How High Is Up?

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