March 23, 2009
BehindTheMedspeak: Tetrachromatic Vision
Mutant females walk the planet, possessing a rare capability: they have four types of cones in their retinas (tetrachromacy) instead of the normal three (trichromacy), which may create the ability to perceive a broader range of hues than normal.
The fourth pigment results from a mutation in one of the longer-wavelength X-linked pigment genes and shifts the spectral sensitivity of the retina.
Women with this mutation would not necessarily be aware of their enhanced visual power, as it is the norm to them.
The first known human tetrachromat, an English social worker identified in 1993, sees 10 distinct colors looking at a rainbow, whereas the rest of us see only five.
University of Washington color vision researcher Jay Neitz estimates that 2 to 3 percent of the world's women may have the fourth type of cone.
Wrote Mark Roth in a September 13, 2006 Pittsburgh Post-Gazette story, "Each of the three standard color-detecting cones in the retina — blue, green and red — can pick up about 100 different gradations of color, Dr. Neitz estimated. But the brain can combine those variations exponentially, he said, so that the average person can distinguish about 1 million different hues."
"A true tetrachromat has another type of cone in between the red and green — somewhere in the orange range — and its 100 shades theoretically would allow her to see 100 million different colors."
Ryan Sutherland's 2001 paper entitled "Aliens Among Us: Preliminary Evidence of Superhuman Tetrachromats," concluded with a section entitled "What would it be like to be a tetrachromat?"
Unfortunately, in this day and age it would likely be very frustrating, especially since most tetrachromats are likely unaware of their unique abilities. In time, though, this may change as we learn about what it is and how to recognize it. Besides the genetic, cognitive, and philosophical interest in learning something new about perception, the brain, and the evolution of our species, tetrachromacy suggests many practical possibilities, but also psychological concerns.
What advantages would a tetrachromat have? It's hard to say, though Gabriele Jordan suggests thinks superior skin tone distinction, such that a tetrachromat mother may be able to more easily spot if her child is flushed or pale. No doubt, tetrachromats would be capable of far superior colour-matching. Unfortunately, the modern world is geared up exclusively for trichromat perception. To a tetrachromat, television and photography would fail to reproduce colours correctly. Computer monitors, paper inks, clothing dyes, and even artwork would not be perceived as intended. But this could be a good thing, making tetrachromats invaluable for jobs involving colour comparison, such as authenticating artwork and pattern matching, or for recognizing subtle distinctions in skin tones for patient diagnosis, mood reading, lie detection, and make-up artistry. In addition to seeing more colours, a tetrachromat might possess a red photopigment shifted slightly further into infrared wavelengths, enabling them to see beyond the natural limit of human perception, allowing for cat-like night-vision, and perhaps even directly perceiving hints of body heat.
A mathematical analysis of the dimensionality and topology of the tetrachromatic color space is here.
José Andrés' Liquid Olives
Pictured above on the white implements, they're part of a $10 appetizer at Andrés' Bazaar restaurant in Los Angeles.
Wrote Frank Bruni in his "Critic's Notebook" feature in the March 18, 2009 New York Times Dining section, "Order them [olives] and a few come in a tin, pierced by toothpicks and stuffed with anchovy and piquillo pepper, as they might have been ages ago. The others come one apiece on curved white spoons, and they’re actually translucent balls of liquefied olive, held together by the thinnest of membranes and the miracle of modern kitchen science. Each ball is to be eaten in one bite, because it explodes instantly, a blast of olive essence."
"But he’s never paired them with ordinary olives so a diner could evaluate the riffs side by side and understand them merely as different delivery systems for the same flavor, the same pleasure."
Barbie then and now
Monica Hesse's article in yesterday's Washington Post has the back story on Mattel's 50th anniversary iteration (below) of the iconic self-hatred machine, introduced in 1959 (above, the original).
USB Plasma Ball
Allen Institute for Brain Science
Long story short: Microsoft co-founder Paul Allen decided to put serious money into a monster of a quest: map the human brain, describing the cerebral cortex down to the level of specific genes and individual neurons.
It's always interesting to stop by the institute's website to see what's going on.
On November 13, 2008, for example, the institute (founded in 2003), released two new data resources: the Allen Brain Atlas — Developing Mouse Brain, and the Transgenic Mouse Study.
The expected completion date of the Allen Human Brain Atlas is 2012.
Computational biology at the bleeding edge.
World's most technical pouring bowl
No moving parts, yet with "8 unique features to make your work easier."
1. Narrow channel directs contents toward spout
2. High sides keeps ingredients from spilling over
3. Measurement marks let you add the right amount
4. Pivoted spout sits on the rim of the bowl to make pouring stable
5. Flat edge of spout prevents drips
6. Comfort-grip handle
7. Egg-cracking ledge
8. Non-slip base
Set of two bowls (one 6-cup and one 8-cup capacity): $21.95.
WMD 2.0 — Red Laser Weapon of Mosquito Destruction
A quarter century after the real life "Star Wars" anti-missile system's heyday, lasers have been repurposed to attack the scourge of the Third World: mosquitos.
Here's Robert A. Guth's March 14, 2009 Wall Street Journal front page story with the details.
Rocket Scientists Shoot Down Mosquitos With Lasers
Humans, Butterflies Remain Unharmed; The 'Star Wars' Connection
A quarter-century ago, American rocket scientists proposed the "Star Wars" defense system to knock Soviet missiles from the skies with laser beams. Some of the same scientists are now aiming their lasers at another airborne threat: the mosquito.
In a lab in this Seattle suburb, researchers in long white coats recently stood watching a small glass box of bugs. Every few seconds, a contraption 100 feet away shot a beam that hit the buzzing mosquitoes, one by one, with a spot of red light.
The insects survived this particular test, which used a non-lethal laser. But if these researchers have their way, the Cold War missile-defense strategy will be reborn as a WMD: Weapon of Mosquito Destruction.
The scientists' actual target is malaria, which is caused by a parasite transmitted when certain mosquitos bite people. Ended in the U.S. decades ago, malaria remains a major global public health threat, killing about one million people annually.
A new global arms race is escalating: the one to protect us from the mosquito.
Efforts to eradicate the disease languished for years until recently.
Big-money donors like Bill Gates, the United Nations, the U.K. and non-profit such as Malaria No More re-launched the war on malaria, devoting billions of dollars to vaccines, methods of prevention and novel ways to kill mosquitoes.
"You can say we are very lucky -- the right place at the right time," says astrophysicist Szabolcs Márka, a Columbia University specialist in black holes. He has a grant to develop a "mosquito flashlight" designed to knock out the bugs' eye-like sensors.
Scientists around the world are testing ways of thwarting mosquitoes with microwaves, rancid odors, poisoned blood and other weapons that disrupt the sense of sight, smell and heat mosquitoes use to find their prey.
There's work on genetically altering a bacterium to infect and kill a mosquito, and a project to build a malaria-free mosquito genetically enhanced to overtake the natural kind.
There's also a researcher in Japan who thinks mosquitoes can be a force for good. He is working on transforming them into "flying syringes" that deliver vaccines with every bite.
The mosquito laser is the brainchild of Lowell Wood, an astrophysicist who worked with Edward Teller, father of the hydrogen bomb and architect of the original plan to use lasers to shield America from the rain of Soviet nuclear arms.
President Ronald Reagan embraced the idea in the 1980s, dubbing it the Strategic Defense Initiative.
Senator Edward Kennedy mocked it as "Star Wars." Eventually it became a footnote in history.
Its rebirth as a bug killer came thanks to Nathan Myhrvold, a former Microsoft Corp. executive who now runs Intellectual Ventures LLC., a company that collects patents and funds inventions. His old boss, Mr. Gates, had asked him to explore new ways of combating malaria. At a brainstorming session in 2007, Dr. Wood, the Star Wars architect, suggested using lasers on mosquitoes.
Soon Dr. Wood, Dr. Kare and another Star Wars scientist teamed with an entomologist with a Ph.D in mosquito behavior and other experts. They killed their first mosquito with a hand-held laser in early 2008.
"We like to think back then we made some contribution to the ending of the Cold War" with the Star Wars program, Dr. Kare says. "Now we're just trying to make a dent in a war that's actually gone on a lot longer and claimed a lot more lives."
The scientists envision their technology might one day be used to draw a laser barrier around a house or village that could kill or blind the bugs. Or, laser-equipped drone aircraft could track bugs by radar, sweeping the sky with death-dealing photons.
They now face one big challenge: deciding how strong to make the weapon. The laser has to be weak enough to not harm humans and smart enough to avoid hitting useful bugs. "You could kill billions of mosquitoes a night, and you could do so without harming butterflies," says Mr. Myhrvold.
Demonstrating the technology recently, Dr. Kare, Mr. Myhrvold and other researchers stood below a small shelf mounted on the wall about 10 feet off the ground. On the shelf were five Maglite flashlights, a zoom lens from a 35mm camera, and the laser itself -- a little black box with an assortment of small lenses and mirrors. On the floor below sat a Dell personal computer that is the laser's brain.
The glass box of mosquitoes across the room is an old 10-gallon fish tank. Each time a beam strikes a bug, the computer makes a gunshot sound to signal a direct hit.
To locate individual mosquitoes, light from the flashlights hits the tank across the room, creating tiny mosquito silhouettes on reflective material behind it. The zoom lens picks up the shadows and feeds the data to the computer, which controls the laser and fires it at the bug.
In a video, researchers showed what happens when they deploy deadly rays.
A mosquito hovers into view. Suddenly, it bursts into flame. A thin plume of smoke rises as the mosquito falls. At the bottom of the screen, the carcass smolders.
There's ready supply of fresh recruits nearby, where an intern feeds a saucer of goat blood to a colony of Anopheles stephensi, one species of mosquito that transmits malaria.
Not only can the laser target a mosquito, it can also tell a male from a female based on wing-beat.
That's a crucial distinction, since only females feed on blood and thus transmit disease. Males in the wild eat sugary plant nectar. (In the lab they get raisins.)
"If you really were a purist, you could only kill the females, not the males," Mr. Myhrvold says. But since they're mosquitoes, he says, he'll probably "just slay them all."
"So realistic you'll want to scrub your hands after using it."
"And no one will borrow it."