Cocktail Party Physics

a shot in the dark: the acoustics of gunfire

Who shot first, Han Solo or Greedo? If you're a diehard Star Wars fan, you know the answer is Han Solo. It's a popular bit of geek trivia, referring to a classic scene in what is now known as Star Wars Episode IV: A New Hope. Fans have engaged in heated online debates, signed petitions, and broken off budding friendships over this pressing issue. And now, thanks to advances in the acoustics of gunshot forensics described at last week's Acoustical Society of America conference, those in the "Han Shot First" camp -- and Jen-Luc Piquant reminds you that there is no other acceptable answer -- can bring in the mighty fists of science to make an even stronger case.

You remember the scene. Han meets bounty hunter Greedo at the Mos Eisley Cantina. Greedo is there to collect on behalf of Jabba the Hut, who wants payment for a load of smuggled cargo that Han dumped to avoid getting caught. The two -- well, one man, one strange-looking alien -- sit across from each other. Greedo has his blaster pointed at Han, who, as they chat, positions his own blaster beneath the table. In the original theatrical release, Greedo says, "Ive been looking forward to this for a long time," and Han replies, "Yes, I'll bet you have." He then blows Greedo away before the bounty hunter manages to take his shot. (Pic below via Mental Floss.) Except fans were outraged when director George Lucas modified the scene for the film's re-release in 1997. In the modified scene, Greedo fires first, missing Han Solo despite the point blank range (Greedo is a pretty horrible shot for a bounty hunter), and Han only fires and kills Greedo in retaliation. Apparently Lucas didn't want there to be any moral ambiguity whatsoever surrounding Solo's ultimately heroic character -- but that ambiguity has always been a big part of the character's charm. (Think the redemption of Spike in Buffy the Vampire Slayer for a similar character arc.) You don't mess with the Star Wars canon, people -- even if your name is George Lucas.

But what if you were a cantina patron whose view of the table where Han and Greedo was sitting was blocked? When the authorities asked for your account of the shooting, how much could you really tell them about what happened, when you only heard the blaster shot? You might be able to tell them quite a bit, actually assuming you'd boned up on the latest acoustics research on gunshot forensics.

Okay, granted, nobody's done a bona fide study on sci-fi blasters, but acousticians Steven Beck (BAE Systems in Austin, Texas) and the FBI's own Hirotaka Nakasone have collaborated on a number of studies of gunshot recordings of various types of firearms, wit microphones placed in many different configurations and angles relative to the gun being tested. They've combined those findings with visual evidence (photographs of gunshots) to develop more accurate waveform models for forensic audio analysis of actual gunshot events.

A waveform is a kind of acoustic signature of a given sound. So waveforms can contain a lot of useful information for someone who's trained to interpret them, once there's a reliable catalog of waveforms associated with specific sounds, of course -- in this case, different kinds of gunshots at different ranges and angles. For instance, a trained analyst might be able to determine whether a sound is a gunshot or not, or how many guns were used, or -- most relevant for Star Wars fans -- who fired first. It turns out that a gunshot "acoustic event" (i.e., "sound") has more than one component. First there is the muzzle blast (the loud bang that propels the bullet forward), which sounds like a short pop in laboratory conditions, but is louder with more reverberation in a more real-world setting. Factors that can affect the resulting waveform from this part of the gunshot include the make of firearm, model, length of the barrel, and the type of ammunition used.

The muzzle blast is followed by a ballistic shock wave, i.e., the crack as the bullet zips through the air, traveling faster than the speed of sound. It's basically a supersonic boom, as the shock wave forms a cone behind the speeding bullet. You don't always hear it either, if you happen to be standing at more than a 90 degree angle to the line of fire. How big the shock wave is, and how long it lasts, depends on such factors as the bullet's speed and its size, while the usefulness of a recording of the ballistic shock wave depends on where the microphone is located, relative to the line of tire. Per Beck and Nakasone's lay language writeup for the conference:

"Currently analysts use simple blast waveform models and cross correlation techniques to study acoustic gunshot waveforms and try to answer basic forensic questions." However, "There are many variables that can affect recorded gunshot signals and forensic audio analysts need to be aware of their influence on the resulting waveforms."

That's why the two acousticians performed so many different kinds of studies of recordings made in both the lab and the field, trying to take into account the many, many factors and conditions that could change a waveform in significant ways, and make it less accurate (and hence less useful) for forensic purposes.

The resulting waveforms matched closely with their theoretical models, at least for the high-quality recordings they made themselves in the lab, with top-notch equipment. Beck and Nakasone acknowledge that for real-world purposes, the kinds of gunshot recordings an acoustic analyst encounters are likely to be done with handheld devices like cell phones, with a lot of background noise. "Waveforms recorded under more realistic conditions can vary significantly -- even to the point of being unrecognizable and forensically unusable," they admitted in their lay language paper.

The culprit is reverberation, or the echoes that distort the waveform, not to mention from the recording equipment itself. Most gunshots occur in urban settings, so the sound will ricochet off pavement, buildings, even nearby parked cars. Beck and Nakasone focused their efforts on recordings of gunshots in the field, and then compared those with those made in the lab, but there are also "acoustic event locating systems" used by military and law enforcement officials.

Such a system was implemented in parts of Washington, DC, back in 2006. It was even featured on an episode of Bones, in which the female serial killer known as the Gravedigger is assassinated by a long-range sniper outside the courthouse for an appeals hearing. The mighty crime-fighters at the Jeffersonian use the sensor system to pinpoint the likely source of the gunshot via acoustic triangulation.

There's more than one kind of acoustic sensor used in these kinds of systems. Per How Stuff Works (a.k.a., "The Enormous Time Suck for the Eternally Curious"), some sensors detect the sonic boom a speeding bullet produces as it moves faster than the speed of sound, while others detect the optical effects produced by a muzzle blast. The DC system uses the former variety, spacing a dozen or so sensors per square mile. Those sensors can each detect the sound of gunfire within a two-mile radius. Since the speed of sound is well-established, all you need to do is measure the difference between the time it takes for the sound of the gunshot to reach three different sensors to figure out the exact location using standard GPS. That's acoustic triangulation.

Then this information gets relayed to the nearest 911 call center, and the police are on it, people. At least that's the main idea. It's pricey -- DC spent millions of dollars on the system -- but it can cut the response time for a "shots fired" 911 call in half, according to DC police officials. If only we had the film equivalent of such a system, or highly trained forensic audio analysts, to settle once and for all what every Geek and Gamer Gurl knows: that Han Shot First. (FYI, video below is a parody of Katy Perry's "California Gurls.")

 

liar, liar

I'm tired of the stories that you always tell

Shakespeare couldn't tell a story that well

You're the largest liar that was ever created

You and Pinnochio are probably related

-- Too  Much Joy, "That's a Lie"

So, I was all set to blog last weekend and then came down with a nasty cold. But I recovered just in time to take the Spousal Unit to dinner and a movie for his birthday. The film: Ricky Gervais' The Invention of Lying. It didn't have the strongest opening weekend, but it's an excellent satirical film that is very funny yet also poses some interesting questions for viewers inclined to ponder the implications a bit more deeply. Jen-Luc Piquant is just relieved to see a film that gets its humor from actual ideas, rather than broad farce in questionable taste, and encourages everyone to support the film's flagging box office by going to see it -- twice. The Invention of Lying has its farcical moments, mind you -- Jen-Luc Piquant is not a prude -- but as anyone familiar with his standup routines (or the British version of The Office) well knows, Gervais is a master of understatement; he doesn't feel the need to try too hard to make us laugh. (Personally, I'd pay to see Gervais read aloud and comment upon just about anything, including Proust; the man is that clever and funny.)

The film's premise is simplicity itself. What would the world be like if nobody could lie -- not even a harmless little white lie? In the world envisioned by Gervais, brutal honesty is the order of the day. Nobody is capable of hiding disdain, dismay, insecurity, or outright hatred. "Movies" are dry, boring documentaries of great moments in history, narrated by "actors' incapable of pretense. Poor Mark Bellison (Gervais) is about to lose his job as a screenwriter; he was assigned one of the least interested and depressing historical eras: medieval Europe decimated by the Black Plague. And he's about to be evicted from his apartment, on the eve of a blind date with the girl of his dreams (Jennifer Garner), who enjoys his company but is frankly a bit out of his league, as everyone seems compelled to tell him -- including their waiter, who also announces how unhappy he is with his job, and that he sampled their drinks before serving them. But then the hapless Mark suddenly develops the ability to lie, or in his words, "I said something... that wasn't!" We are treated to an image of neurons in his brain firing in new ways at that pivotal evolutionary moment (see clip below).

In reality, lying is probably as old as humankind, and the elusive ability to tell when someone is lying has consumed a great deal of brainpower over the ages. Or, as David Thoreson Lykken phrases it in his classic book, A Tremor in the Blood: "If man learned to lie not long after he acquired language, we may assume that the first attempts at lie detection soon made their appearance....We are all human lie detectors; we must be to survive in our mendacious society."

So it's not surprising, then, that lie detection has a long and colorful history. It has its roots in instruments of torture, most notably during the European Middle Ages, when it was believed that subjecting the body to extreme physical agony would force the victim to blurt out the truth. (We now know that this is far from the case. An Italian Enlightenment thinker, Cesare Beccaria, wrote in 1764, “By this method, the robust will escape, and the feeble be condemned. These are the inconveniences of this pretended test of truth.”) In 1730, Daniel DeFoe suggested it might be possible to measure someone's heart rate to detect deception. 

The evolution of the modern lie detector, or polygraph machine, began with the first tests to determine the physical responses of the body during the act of deception. In 1895, the so-called “ ‘Father of Modern Criminology,’” Cesare Lombroso used a device called a plethysmograph to monitor changes in the blood flow of a subject during interrogation; two years later, in 1897, B. Sticker developed a method of measuring the galvanic responses of an individual under interrogation: i.e, the amount of sweat they produced as determined by the electric conductibility of their skin. Finally, in 1914, Vittorio Benussi began to study the breathing rates of individuals, using pneumatic tubing wrapped around the subject’s chest to measure depth and rate of breath. He found that the “ratio of inspiration and expiration was generally greater before truth telling than that before lying.” So not only could blood pressure, pulse rate and sweat production be linked to the act of lying, but breathing rates as well.

All these components are combined in the modern polygraph machine, which measures physical responses such as respiration, heart rate, pulse, and electrical skin conductance to determine if a subject is lying, are notoriously unreliable. Its invention is largely credited to William Moulton Marston, an American psychologist who in 1915 began to demonstrate a lie detection test, which determined whether the subject was being deceptive using a blood pressure cuff, or sphygmomanometer, to take measurements of systolic blood pressure during interrogation.

(Interestingly, he also created the comic book character Wonder Woman under the alias Charles Moulton. Wonder Woman was known for her Lasso of Truth that compelled people to tell the truth when wrapped in its coiled -- clearly, Moulton had serious trust issues. Maybe it had something to do with his polyamorous lifestyle: he and his wife lived with a third woman, Olive Byrne, for many years.)

An American medical student and an employee of the Berkley police department,named John Larson, is credited with the first "polygraph" to be used in forensic science: he adapted the scientific procedure created by Marston in the Harvard Psychological Laboratory and adapted it to police procedure beginning in 1921. Like Marston, Larson recognized the importance of asking questions in the correct order, and wording them in specific ways, as being critical to lie detection -- the apparatus was just the supporting device. Larson called his invention a "cardio-pneumo-psychogram," because it documented blood pressure, pulse rate and respiratory rates, all on a drum of paper.

The problem with polygraph tests is that they are notoriously inaccurate and people can train themselves to beat the machine. Most notably, they only measure physiological responses; determining whether those responses indicate a lie is the job of the person administering the test -- which makes the results highly subject to interpretation. Or as the American Civil Liberties Union puts it: "The lie detector does not measure truth-telling; it measures changes in blood pressure, breath rate, and perspiration, but those physiological changes can be triggered by a wide range of emotions."

The most common countermeasures to beat the polygraph include sedatives, putting antiperspiranton the fingerprints, biting the tongue, lips or cheek, or placing tacks in one's shoe. In Ocean's 13, for instance, a character beats a polygraph test by stepping on a tack whenever he answers a question truthfully, skewing the machine's readings and making it harder to determine the difference between lies and truth. But it's not a simple matter either; it requires a bit of skill to beat the polygraph. The Mythbusters notoriously attempted to fool a polygraph in one of their episodes, and failed miserably.

Anyone still supporting the accuracy of the polygraph is going to have to come up with some seriously convincing solid evidence to win over the scientific community at this point. In 2003, the National Academy of Sciences released a report called The Polygraph and Lie Detection, concluding that most such research was "unreliable, unscientific and biased," based on the group's analysis of 57 research studies on which the APA bases its reliability.

Okay, those studies didn't completely bomb: the report concluded that polygraphs can detect a lie "at a level slightly greater than chance, yet short of perfection"; however, correct results were habitually over-stated, "almost certainly higher than actual polygraph accuracy of specific-incident testing in the field." Lots of devices work wonderfully in the carefully controlled conditions of the laboratory, but "slightly greater than average" accurate readings doesn't inspire a great deal of confidence in the technique.(A common misconception is that, when properly conducted, a polygraph is accurate 80-99% of the time. The NAS report contradicts that widespread belief.)

As recently as this past April researchers at the University of Florida conducted a study in the Journal of Forensic Sciences demonstrating the inaccuracy of standard lie detection techniques. The researchers hooked up 78 test subjects (men and women of all ages) to voice stress analyzes and used those devices to analyze vocal frequency of the speakers to determine when they were lying. The volunteers were instructed to lie while undergoing small electric shocks to simulate stress. The result? "[T]he 'true positive' (or hit) rates for all examiners averaged near chance (42-56%) for all conditions," the researchers concluded. "Most importantly, the false positive rate was very high, ranging from 40% to 65%." That was true even when representatives from the device manufacturers conducted the tests, as opposed to the scientists.

The shortcomings of traditional polygraph techniques were succinctly demonstrated in a scene from Lie To Me's first season, when the fictional Cal Lightman debunks a new handheld lie detector device under demonstration. There actually is such a device being used by US Department of Defense called the Preliminary Credibility Assessment Screening System (PCASS); apparently it relies less on the judgment of a polygraph examiner and more on a special algorithm to determine whether a subject is lying, based on the measured physiological responses. But we've just seen that those responses can be misleading, and are not always indicators of deception.

In the episode, the (male) test subject performs quite well when being interrogated by a bland male examiner, but then Lightman sends in a sexy young woman to ask the same questions in a more flirtatious, suggestive manner -- and the subject exhibits a physiological response similar to "lying" when he is really feeling self-conscious about his sexual arousal. Lightman likens the handheld device to a West African tribal custom in which a bird's egg is passed to someone suspected of a crime. If the suspect broke the egg, s/he was found guilty, because obviously they broke it out of nervousness, and if they were nervous -- well, then they must be guilty!

Lie to Me - Behind the Scenes Featurette

Lightman's character is based on real-life scientist Paul Ekman, who pioneered the use of so-called "microexpressions" to determine whether or not someone is lying; he calls his approach the Facial Action Coding System, and it classifies every human expression, including the unconscious body mechanics of decetion. For instance, there are telltale arm and movements, eye contact, and verbal contexts, all of which combined can reveal whether or not someone is being truthful (in theory, anyway). A liar won't make eye contact, and may compulsively touch his/her face, throat or mouth, or touch or scratch the nose or behind the ear. S/he will not be likely to touch the chest or heart area with an open hand. If someone says "I love you" while frowning, s/he is likely lying -- the gestures or expressions don't match the verbal statement. The timing and duration of gestures and expressions are also useful determining factors. And we've all met that person whose smile never quite reaches their eyes, making us feel like their cheerfulness is insincere.

It's an admittedly inexact science, something the show makes clear: Lightman and his team are not infallible. For instance, he mistakenly concludes a mother is not sufficiently grieving for her child and hiding some guilty truth because of the lack of the telltale microexpressions accompanying such emotion. Then Lightman realizes that she is hiding something: her age. The mother has received Botox treatments, which numb the tiny facial muscles that give rise to microexpressions in the first place.

Further complicating matters is the fact that people lie for various reasons and motivations -- not just because they are guilty of some crime. In the case of the aforementioned episode, "He Said, She Said," Lightman determines that a female soldier has made a false accusation of rape against a male colleague. But she is lying on behalf of another woman who is too terrified to come forward -- a noble impulse, even if the ends don't justify the means. Mark, the hapless screenwriter in The Invention of Lying, lies for all kinds of reasons: initially out of desperation to avoid being evicted, then to advance his career and romantic prospects -- although he can't bring himself to tell a lie to convince the woman of his dreams to be with him, even though it means she will marry his arch-rival. And, in the most heart-breaking scene, he lies to comfort his dying mother, who is terrified of the Void -- a truly altruistic lie that quickly spirals out of control.

Nonetheless, scientists are still looking for the equivalent of Wonder Woman's magical lasso of truth. Scientists have been looking into using functional magnetic resonance imaging (fMRI) to achieve a kind of "brain fingerprinting" as a means of lie detection. In fMRI, when certain parts of the brain are engaged during a specific cognitive activity, those areas light up in the brain scan -- and if a person happens to be "dissembling," it should be possible to tell that they are lying just by looking at the scan.

Brain fingerprinting seems to offer something closer to an objective analysis of whether or not not someone is lying. How can a brain scan lie, after all? Well, maybe the scan doesn't lie, but how we interpret those images is prone to human error, particularly since we don't fully understand how this complicated organ called the brain actually works. Chief among the naysayers of this new "mind reading" technology is Melissa Littlefield of the University of Illinois, who argues that the technique is based on fundamentally wrong assumptions, most notably "truth" is the baseline, the natural state of being, and lying is adding "a story on top of the truth." That might be true in Gervais-Land, but the real world is far more complicated.

An fMRI scan might reveal a lie if the person knew he or she was lying -- if it were a conscious decision. But "some people don't actually know that they're lying, or have a told a lie for so long that it becomes their subjective interpretation of reality," Littlefield explains. And just as with the polygraph test, it's possible to cheat and beat the machine: just clench your teeth or move your head slightly. FMRI requires the subject to hold perfectly still to get a usable image.

There are defenders of the technique's potential for lie detection as well. The most recent fMRI work on truthfulness comes to us via Joshua Greene of Harvard University, who published his results recently in the Proceedings of the National Academy of Sciences. He found that honest subjects showed almost no additional brain activity when telling the truth, as might be expected -- you're not inventing a lie, after all. But dishonest subjects did show extra brain activity... even when they were telling the truth. Greene's conclusion: "Being honest is not so much a matter of exercising willpower as it is being disposed to behave honestly in a more effortless kind of way."

Then again, compulsive honesty in all situations has its drawbacks. Would any of us really want to live in the fictional world envisioned by Gervais, where nobody has any kind of filter and hurtful truths are uttered on a daily basis? Lie To Me has its own similar character in Eli Loker (Brendan Hines), who has taken a vow of radical honesty in response to his work -- which includes admitting to his female love interest, Ria, that he's only slightly above average in terms of sexual performance. Ria gets in her own zinger when Lightman asks if she has any specific training in spotting deception: "Well, I've dated a lot of men." Little white lies are an integral part of our social fabric. As the Mitchell & Webb sketch below illustrates, sometimes one can be too much of a stickler for the truth.

CSI lies and suspicious science

Or, Don't Try This in Your Home Lab, Kids!

Forensic science has come a long way since Sherlock Holmes bragged that he could identify 140 types of tobacco from their ash. And far be it from me to diss one of my favorite shows on the TV I don't own, the original CSI, which is loaded with fantastic sciency goodness, even if it is a little unrealistic. CSI? Unrealistic? Hate to break it to you kids, but, yeah. At the very least, the speed with which our intrepid heroes get their results would make any cop, ADA, or defense attorney double over in laughter, when they're not crying. DNA rape kits, appallingly, have as much as a six year backlog, according to a recent NY Times Op-Ed. That's not just because of the volume of cases involved, but the time it takes to analyze and match DNA samples.

 One of the reasons there's such a huge backlog is because of the complexity of testing and matching DNA. The molecule, as many of you may know, is a double helix composed of pairs of four "bases" (nucleotides): adenine, cytosine, guanine, thymine forming "ladder rungs" up the middle. Because of their chemical makeup, adenine only bonds with thymine and only cytosine bonds with guanine. Because there are millions of base pairs in every strand of DNA, the order in which these pairs bond on the molecule can be used to "fingerprint" both species and individual characteristics. But also because there are millions of base pairs, it's most useful (and quicker) to use known repeating pairs which are known to vary among individuals. Analyzing these can tell whether a DNA sample matches one from the same person, relations, or a complete stranger, not absolutely, but within a percentage of probability.

The actual fingerprinting is a four-step process, starting with the Southern Blot test and progressing through a radioactive probe, hybridization and the most accurate step, comparing Variable Number Tandem Repeats (VNTRs). The Southern Blot is where the DNA molecule is squeezed out of the cells, cut into pieces, and "unzipped" (denatured). Then it's nicked and marked with radioactive material to label the sequences. Each of these steps have their own individual processes, so a single analysis of one sample is a long process that can go wrong at any one of these steps. Then there's the kits used to gather the evidence. One of the biggest problems with DNA evidence is that it degrades over time, so the longer they sit in storage, the less chance there is of an accurate analysis. That's why that six-year backlog is worrisome. So that DNA matching thing? It's not perfect.

 Meanwhile, that cool favorite of our CSI heroes, Luminol, the chemical that makes blood long scrubbed away show up in dramatic blacklight dayglo, turns out to be susceptible to false positives from household substances as common as Drano crystals and bleach. A competing product called Hemaglow, while easier to use in the field and not as sensitive to false positives, is also less sensitive to diluted blood than Luminol. I actually first heard of the false positives problem in a mystery novel called In the Woods by Tana French (never underestimate what you can learn from fiction). But false positives are a problem in almost any chemical test. False positives turn up because the test is reacting to some substance that's similar to the one it's testing for, even if it's just the tag end of a completely different molecule. Field tests tend to be not very sensitive, for practical reasons, since accurate chemical analysis requires controlled conditions and technical knowledge. Most field tests are simple to use, but more like a dragnet than a fine-mesh seine.

For instance, the field test for the date-rape drug GHB turns up false positives to (wait for it . . .) soap. The test is simple to use: put the suspect substance in a pouch, seal it, break the enclosed ampule and watch the pretty colors. Check out this video, in which the drummer for the Germs, Paul Bolles, is busted for alleged possession of GHB, er, soap. (Once again, truth is stranger than fiction. Or at least more ironic.) You'll also get a quick lesson on how good soap is made.

While we're on the subject of field tests, what about those Breathalyzers? The good news (for drinkers) is that they're notoriously bad. The bad news (for law enforcement) is that . . . they're notoriously bad.  I'll let David J. Hanson, Ph.D., Professor Emeritus of Sociology of the State University of New York at Potsdam sum them up:

A major problem with some machines is that they not only identify the ethyl alcohol (or ethanol) found in alcohol beverages, but also other substances similar in molecular structure. Those machines identify any compound containing the methyl group structure. Over one hundred compounds can be found in the human breath at any one time and 70 to 80 percent of them contain methyl group structure and will be incorrectly detected as ethyl alcohol. Important is the fact that the more different ethyl group substances the machine detects, the higher will be the false BAC (blood alcohol concentration) estimate.

The real problem with Breathalyzers is that they only estimate your BAC; only a real blood test can provide a truly accurate reading, so demand one if you're pulled over. Because there are so many compounds that contain that methyl group structure, it's not that hard to get a false positive, not just from your own breath, but from environmental factors. It depends on where the test is administered and what local pollutants are in the air, and whether you've been, say, spray painting something in the last hour or so. It can also depend on your own body chemistry.

One of the compounds containing the methyl group structure is acetone (dimethyl ketone), not uncommonly found in the breath of diabetics and some low-carb dieters. In addition, the symptoms of hypoglycemia (and strokes or seizures) can mimic the symptoms of intoxication. It's not unheard of for people suffering hypoglycemia to be pulled over and accused of DWI. Driving while hypoglycemic is probably just as dangerous as DWI, but not criminal.

Which brings us to a newish and disturbing trend in law enforcement: suspicion of science. i09's Annalee Newitz posted a story about about a University of Saskatchewan chemistry major who was busted on suspicion of having a home meth or bomb lab in his parents' garage. The cops later decided it wasn't a meth lab, but that he might be making explosives with the chemicals they found. Like, oh, fertilizer (which, granted can be used in both meth production and explosives, but only in large quantities). Lots of other stuff commonly found in your home goes into meth production, and you certainly don't need lab ware to cook the stuff; a coffee maker will suffice. Which makes me glad I'm a tea drinker; I'd hate to be busted for owning a Mr. Coffee (and read the comments here, if you think I'm kidding). Or too many antihistamines.

Newitz rightly points out the similarity between this case and Steve Kurtz's, in which the FBI could not tell the difference between petri dishes of harmless bacterial cultures sitting in the open air and biological weapons. Initially facing 20 years in prison for making art that was critical of genetically modified food, Kurtz has finally had his stash of commonly available lab components and living art projects returned by the FBI and been cleared of all charges. Both of these cases point to a certain amount of scientific ignorance on the part of law enforcement officials, the same kind that sent the artist's books of Edith Kollath's into the black hole of the FBI's evidence room because they contained electronic devices and she was hand-carrying them onto a plane to return home to Germany. The electronic devices? Little engines inside the books that made them appear to breathe by pushing their covers and pages up and down. I suspect these were not complicated devices. How hard would it be to tell they weren't detonators?

So there's some cognitive dissonance going on not just in law enforcement but in our culture as well. Law enforcement has increasingly relied on science to catch and convict lawbreakers from drunk drivers to terrorists; at the same time, many law enforcement officials on the ground have a hard time drawing a line between criminals and scientific dabblers, whether they're artists, basement inventors, or the merely curious. It also has a tendency to over-rely on the accuracy of techniques that are meant to provide field yardsticks rather than defense-proof  evidence. A little more knowledge about mitigating factors and some general scientific knowledge wouldn't be amiss. We like what science does, but we don't really trust the people who do it.

UPDATE: I just ran across a study "conducted by the Federation of American Scientists (FAS) and the Federal Bureau of Investigation (FBI) revealed that while scientists are disposed to assist in criminal investigations, they often fear working with law enforcement agencies." One of the key findings:

Scientists feel that the FBI does not work well with the scientific community, specifically that law enforcement officers don't understand their work (76%), that these agencies are more interested in restricting research for security purposes than they are in the scientific value of the work (71%), that officers have an overzealous approach to security issues [emphasis mine] and an interest in censorship (63%), and that research will be restricted from publication (55%).

Surprise! Not, in light of the episodes I cited above.

But it's not all bad news from the world of forensics. There's a new fingerprint test that's showing some success in lifting even prints that have been wiped away, at least from things like shell casings. It works on the corrosion caused by sweat rather than by "developing" the residue of the secretions themselves, which can be wiped away. The salts left behind by sweat are heated with an electrical charge after being coated with a powder that reacts to the ionic salts that cause corrosion and are left behind by sweat, even after wiping. Unlike fingerprint secretions, corrosion is forever and happens on a micro leve whenever we touch metals that react to our body chemistry, like brass. Watch the National Geographic video about it. And remember to leave your gloves on when you pick up those shell casings. Oh, and rinse out that Mr. Coffee pot really well, too.

blood rituals

It's All Soul's Day, and Jen-Luc is proudly sporting her vampire look for the occasion, eschewing the usual Halloween festivities last night. She embraces the notion (popularized on Buffy the Vampire Slayer) that vampires and other nasty things actually take the night off on Halloween -- because they find the whole spectacle beneath their Evil Dignity or something. I'm especially reminded of the episode where a semi-reformed Spike joins the "Scoobies" in warding off a group of vampires who decide to flout the tradition. Mid-fight, one of the vamps asks Spike, "What's your problem, man?" Spike reminds him of the tradition, to which the vamp blusters, "Yeah, well, I'm a rebel." Which causes Spike -- never the most patient of vampires -- to roll his eyes and stake the poor bastard, declaring, "No, I'm a rebel. You're an idiot." Also? A big pile of dust.

Naturally, I'm a vampire fan -- but only because I'm pretty confident the creatures don't exist. Okay, maybe there are some rare albino folks out there with a serious melanin deprivation, making them ultra-sensitive to sunlight. (And what was the rare disease that supposedly afflicted the unfortunate children in The Others? Oh right, xeroderma pigmentosum.) The hereditary disease known as porphyria has become associated with vampirism, with historians speculating that the legends arose from early sufferers. This is a disease in which the body doesn't produce enough heme, an iron-rich pigment in the blood, making victims sensitive to sunlight, sometimes with reddish mouths. (Remember the Master in Buffy? He had "fruit-punch mouth.") There are different varieties of porphyria; the rarest, and most severe, leads to blistering and scarring of the skin, with the lips and gums becoming so taut that teeth protrude like fangs.

In all of recorded history, there have only been 200 or so documented cases of the most extreme forms of porphyria, although it's popping up more and more on prime time TV. For instance, I distinctly recall an episode of C.S.I. where Grissom builds a case against a nutritionist who, it transpires, suffers from porphyria. She has trained her large dog to attack random joggers so she can harvest their blood-rich organs, puree them in the blender, and drink it up to keep her disease at bay. Drinking fresh blood is erroneously believed to be a kind of folk remedy for porphyria. In reality, the chemical enzymes in the blood that the sufferers require can't survive the digestive process; the best way to treat porphyria is through blood transfusions.

There have been a few historical figures rumored to have an especially powerful bloodlust, even in earlier, more violent ages where slow-lingering painful executions were the order of the day. Take Vlad the Impaler, a Wallachian prince (also known as Vlad Tepes or Vlad Dracula) from the mid-1400s believed to be the partial inspiration for Bram Stoker's horror classic, Dracula. He earned his nickname for his penchant for impaling his enemies on long wooden spikes.

Per Wikipedia, this was called "bung poling," i.e., "dropping a person upright onto a sharpened tree trunk starting from between the legs, the weight of the person forcing the tip of the trunk through the chest cavity or neck." Women were not exempt from this punishment, particularly those Prince Vlad deemed unchaste. Actually, by the time he got around to impaling such unfortunate females, it would have been a merciful release, given the sorts of atrocities inflicted upon them beforehand. Maybe Vlad wasn't an actual vampire, but he most certainly was a monster.

When Francis Ford Coppola filmed 1992's Bram Stoker's Dracula, he presented the vampire as actually being Vlad the Impaler, not just inspired by him. This was a highly romanticized portrayal of a sympathetic monster, driven to embrace vampirism by the suicide of his beloved wife, who threw herself out of a castle window into the river hundreds of feet below. Something very like this seems to have happened with Vlad's first wife (name unrecorded) during a siege of his castle in 1462. She jumped out of the castle tower, vowing that she "would rather have her body rot and be eaten by the fish of the Arges (River, flowing below the castle) than be led into captivity by the Turks." (The tributary is, indeed, known as "the Lady's River" or "the Princess' River," as Coppola's film declares.) Considering the Turks were only slightly less barbaric than her own spouse, it was probably a wise choice. What's lacking in this account is any evidence that Prince Vlad was all that upset over the loss of his lady. Life was cheap back then. He married another princess in between various imprisonments and reigns (it was a volatile period), siring a few sons in the process.

Then there is Elizabeth Bathory, a late 16th century Transvylvanian noblewoman of extraordinary beauty who was known as "the bloody countess" because she was rumored to bathe in the blood of young women (more than 600 victims in all) to preserve her youthful appearance, even drinking the blood of the especially pretty ones. Think of it as an especially heinous form of alternative medicine. Local villagers reported hearing screams emanating from the Castle Csejthe, and young peasant girls who went to work as maidservants for the countess never seemed to return. She got away with her diabolical practices for a good long while, until King Mathias of Hungary could ignore the rumors (and missing young girls) no longer. Around Christmas in 1609, he sent a raiding party to the castle to investigate. TruTV has this account of what they found:

"On the cold stone floor of the great hall lay a pale, partially clothed young girl. She failed to move. They wondered if she might simply be asleep or drunk so several men went toward her. Still, she made no effort to rouse herself. One reached down to touch her and shook his head. He told the others she was dead. They turned her over and saw how pale she looked. She appeared to have been drained of blood.... Just a few paces away was another girl, sprawled face up but still alive. The men discovered that her body had been pierced in many places. She was also pale, as if from severe blood depletion. It was clear to them that she would not last long."

The raiding party also found a female corpse chained to a post, also mostly drained of blood, having clearly been beaten, whipped, and burned while still alive. Deeper within the castle, they found prison cells filled with women and children, scarred from frequent repeated blood-lettings -- and greatly relieved to be released, since they were bound for the same fate as the three dead young women found earlier. Oh, and in the private upper chambers, they found "evidence of a drunken holiday orgy, complete with torture." Because really, what's a Christmas party without a spot of ritualistic blood-letting? 

The countess herself was nowhere to be found, having already fled the premises. But they tracked her down and arrested her soon after. After all that hard work collecting fresh blood to maintain her youthful complexion before the Age of Botox and chemical peels, Elizabeth Bathory continued to age, and died in 1614 in her early 50s while imprisoned for her crimes in her own castle, deep in the Carpathian Mountains. See? Alternative medicine doesn't work.

In the 1940s, England caught and executed a serial killer named John George Haigh, nicknamed the "Acid Bath Murderer" because he attempted to dispose of his victims' remains by dissolving their corpses in tubs of concentrated sulphuric acid. He was convicted of killing six people, although he confessed to nine, showing zero remorse in the process. His primary motive seems to have been fraud: he was a compulsive gambler, who had trouble holding a steady job -- he kept getting fired and/or imprisoned for silly things like theft, embezzlement and fraud -- and his murders always seemed to coincide with a particularly low point in his personal finances. It was during one of his prison stints that he dreamed up the "perfect murder": he figured that by destroying a body by dissolving it in acid, there would be no corpse, and thus no evidence with which he could be convicted, which is why he cheerfully confessed to the murders, convinced he couldn't be prosecuted. Such is the convoluted logic of the criminally insane.

Unfortunately, Haigh wasn't nearly so thorough in disposing of his victims' possessions: when they searched his workshop on Leopold Road, police found various personal items belonging to the missing persons (papers, coats, hatboxes, pawn slips for jewelry, etc.), along with the tools of Haigh's nefarious trade. They also found all the acid sludge he'd carelessly dumped in the yard. The acid hadn't quite eaten everything away. The team of pathologists probably deserved some sort of special award of merit for sifting through the stuff, but their efforts paid off. They recovered 28 pounds of human body fat; three gallstones; part of a left foot; 18 bone fragments; a hairpin; and an intact upper and lower dentures, the handle of a red plastic bag and a lipstick container.

The dentures were especially damning, as they matched the dental records of Haigh's last victim. Apparently sulphuric acid doesn't erode plastic quite as easily as human remains. The forensic team performed their own experiments to prove it, putting various items in sulphuric acid. Acid works at varying speeds, depending in part on how much water is present. Human fat is more resistant to the acid; his final victim, Mrs. Durand Deacon, has been quite a heavy woman and her weight helped preserve the items recovered from the sludge

In short: Haigh was busted. He had a handy insanity defense at the ready, though, which is why he's included in this blog post: he claimed that he drank the blood of the victims, and that his killings were prompted by a recurring dream cycle. ("From each of them I took my draught" he said.) A car accident in 1944 supposedly triggered his blood fetish; he suffered a head wound, which bled into his mouth, and thereafter, he claimed, he craved blood, and this would periodically drive him to murder.

There are rare cases of clinical vampirism documented in the medical literature: those with a compulsion to drink blood periodically, often deriving sexual satisfaction from the act, and usually in the belief that they can prolong their lives by doing so. But this is a psychosis, not evidence of supernatural monsters -- or, in the case of a prison inmate trading sexual favors for the chance to drink other inmates' blood, an ill-devised strategy for gaining access to a relatively comfy hospital room rather than his cell. There are also vampire-like cults scattered around the world, and definitely on the Internet, wherein participants can meet, share their vampire fantasies and even drink small amounts of each other's blood. Some have been known to file their teeth into fangs for added verisimilitude to the group fantasy.

(Sidenote: Author Eric Nuzum sought out one such "vampire cult" while writing his book, The Dead Travel Fast. He found a rather pathetic group of social misfits with delusions of psychic powers, rather than any actual blood-fetishists, which had to be a bit disappointing. His book is still a fun read. He attends a Dark Shadows convention, tours Romania with the actor who played Eddie Munster, plays a vampire in the local haunted house, and even tries to drink his own blood, with vomitous results. Good times!)

The serial killers Peter Kurten and Richard Trenton Chase were dubbed "vampires" by the tabloid press when it was discovered they really had drank the blood of their victims. Haigh, however, probably didn't suffer from clinical vampirism. He was just looking for a handy way to avoid being executed for his crimes. There was something a bit too calculated about how he went about luring and killing his victims, forging paperwork to take over their homes and other belongings, pawning their jewelry, and so forth. Nobody really believed he was insane, although he certainly lacked any moral compunction. He was hanged on August 10, 1949, and good riddance to bad rubbish, seemed to be the prevailing popular consensus of the day.

The upshot: those prone to fantastical wishful thinking and rare cases of psychosis notwithstanding, there's no such thing as vampires. The one place where vampires really do seem to exist is in the animal kingdom -- not just vampire bats, but according to the guys at Deep Sea News, there's also a vampire squid. It has certain bioluminescnent capabilities, producing a faint pulsing light to attract prey, the better to eat your face off. Now that's the stuff of All Soul's Day nightmares. I'm guessing Edvard Munch had his share of them, too, judging by his own depiction of a ravenous vampiress devouring her prey:

plastic people

A month or so ago, I wrote a post about the difference (if any) between scientific visualization and science-inspired art, particularly as the former becomes sufficiently sophisticated that the lines really do start to blur. It generated some excellent discussion, although ultimately it comes down to how one chooses to define "art." I mean, lots of things can be aesthetically pleasing on the merits, including natural formations; that doesn't necessarily qualify them as "art" -- otherwise, galleries all over the world could just point to a random patch of meadow or the white cliffs of Dover and call it "art." (We've already seen certain self-styled "artists" come awfully close to that level of dis-ingenuousness in their shows. Who's that guy who displayed dissected cow parts preserved in formaldehyde in jars -- Damien Hirst? -- and claimed he was making some deep artistic statement? Jen-Luc Piquant calls shenanigans!)

So beauty is very much in the eyes of the beholder. I was reminded of this when one commenter mentioned the work of Gunther von Hagens, the mastermind behind the Body Worlds series of exhibits that have been touring science museums around the country for several years now. The Spousal Unit and I took in Body Worlds 4 at the Los Angeles Science Museum a couple of weeks ago. We've been living here almost two years, yet this was the first time we'd explored the science museum, despite the fact that it is literally a 10-minute drive away. (Were LA more pedestrian-friendly, we could have walked there, were we feeling energetic.) Anyone who reads this blog regularly knows I have a morbid streak a mile wide. I've written about forensics, bugs, poisons, physics-based techniques for sorting sperm, mummies, zombies, and yes -- lovely, lovely corpses. So von Hagens' creations are right up my alley. I found the exhibit positively enthralling.

On the off-chance that there are still folks out there unfamiliar with von Hagens' work, he pioneered a method for preserving corpses called plastination back in the 1970s. It's a time-honored, human endeavor, figuring out how to beat back the ravages of decomposition after death, so von Hagens has a lot of ancestors throughout the ages. In essence, when we die, our cells release enzymes to trigger the process of breaking down all that bone and tissue -- ashes to ashes, dust to dust -- with the help of bacteria and other micro-organisms, not to mention insects and so forth. Mother Nature is thrifty that way.

The best way to offset decomposition is to get rid of all the water and fats that those hungry micro-organisms need in order to thrive. The Egyptians did this via mummification (removing the bodily fluids and wrapping the remainder in linens), although before they developed that technique, the body wold be laid out in the desert in a shallow pit so that the sun could dehydrate the body. Around 1896, scientists discovered formalin, followed soon after by color preserving embalming solutions so folks could be assured of leaving a reasonably good-looking corpse -- or at least one with decent coloring. By 1925, paraffin was commonly injected into organs and tissues to preserve them, and (much later) cryopreservation (cooling the body to very low temperatures to stop decay). In between, in 18th century France, there was Honore Fragonard, director of one of the world's oldest veterinary schools. Fragonard had trained to be a surgeon, and had a longstanding fascination with anatomy and preservation.

Back then, anatomists used to soak body parts in alcohol, mixed with pepper and herbs; apparently Fragonard had his own secret recipe for this, but if so, he took it with him to the grave. But it's obvious what he did to his corpses after that initial phase: he injected the veins, bronchial tubes and arteries with wax or tallow mixed with turpentine, then stretched them on a frame into the desired position and left them to dry. Your average anatomist would have just laid out the bodies in some conventional funereal pose, but Fragonard clearly had a sense of whimsy. He arranged his flayed and preserved bodies into intricate tableaux, or ecorches, and these are the highlight of the Fragonard Museum, located in the tiny town of Maisons-Alfort, just outside of Paris.

The museum houses all kinds of monstrous medical specimens: a pale blue horse fetus, for example, or an actual Cyclops (a colt with a malformed facial bone and one enormous eye). There are Siamese twins, sheep with 10 legs, and a host of skeletons of exotic animals: ostriches, camels, and lions, among others. For Fragonard, however, bodies were his raw materials, and he really blurred the boundary between science and art -- pushing the limits of aesthetics to the limit in the process. The museum is not for the faint of heart. A 1996 article in The New York Times reported that the museum displays a hand-lettered sign at the entrance: "Unfortunately we have too few visitors. If you enjoy the museum, why not send us your friends -- if not your enemies."

If anyone can be said to be the modern heir apparent to Fragonard, it is Gunther von Hagens. In 1978, he applied for his first US patent for a technique for preserving tissue permanently by "synthetic resin impregnation." That is, he replaces the water and lipid tissues of the body with curable polymers (plastics), hence the term plastination. He founded the Institute of Plastination in Germany in 1993 after perfecting his technique, and over the last 20 years has plastinated several hundred donated bodies.

First, the donated body is embalmed with formaldehyde and dissected to whatever degree is desired. Then the water and fatty tissues are replaced with the solvent acetone, which in turn is replaced with a liquid plastic (usually silicone rubber for the posed bodies, since it cures when exposed to a special gas). The challenge is to make sure the plastic gets into every single cell. The secret is placing the specimen in a vacuum chamber, reducing the pressure to the point where the acetone literally boils and vaporizes. The vapor is sucked out of the tissue, and the liquid plastic rushes in to fill the void. Apparently it's a very time-consuming process: doing this to entire bodies takes weeks. Then the bodies are posed with needles, wires, and foam rubber holding various muscles and nerves and limbs in place as need be. The film depicting this part of the process was even eerier than the final pieces, because the bodies look just like flayed marionettes. Once posed, the plastic is cured (with gas, UV light, or heat), and it hardens, solidifying the body into the final position.

The end result not only perfectly preserves the corpses, but even retains most of the microscopic properties of the original form. Tendons, ligaments, fine details of the bone and sinew -- all of these are perfectly preserved, looking more like an exquisitely rendered plastic model than an actual preserved human body. The genius of the exhibit is how von Hagens exploits that life-like quality: the bodies are displayed in various athletic poses (see basketball player, below), revealing how all the bones and muscles and tendons and such interact to produce movement. In some cases, the preserved bodies are shown with prosthetics still intact: artificial hip joints, for instance, or metal pins. And the same hints of whimsy can be seen here, as with Fragonard: bodies are shown playing poker, for example, in an earlier incarnation of Body Worlds, and both Fragonard and von Hagens feature a horse and rider.

In between the full-sized tableaux are display cases featuring individual organs, or slices of tissue: a liver with and without cirrhosis, for example, or the lungs of a smoker displayed side by side with a non-smoker. This being southern California, the exhibit got a bit preachy at such times: there was a special canister for smokers to toss out their cigarettes after viewing that icky, tar-infested lung tissue, for instance, and another display showing a preserved, morbidly obese body (or parts thereof) was accompanied by signage primly lecturing attendees on the need to maintain proper diet and exercise.

Now, I'm all for maintaining a healthy weight via good diet and exercise, but really -- give me a break. Do we really need to turn an anatomy lesson into high school nutrition class? Personally, what that obese specimen revealed to me was that in death, with all the excess fatty tissue stripped away, we are all just pretty much bones and tendons and muscle. At that level, we really do all look alike: the universal human form.

a nation of winers

Thomas Jefferson may well have been America's first great wine connoisseur, according to a 2007 article in The New Yorker about the growing epidemic of wine fraud. See, Jefferson spent several years as Minister to France from 1785 until the French Revolution broke out and every sane foreign diplomat fled for this life, Jefferson included. (Jen-Luc Piquant begs to differ; she has some wild pet theory that Jefferson was the Scarlet Pimpernel, no matter how often I point out that this personage is entirely fictional. But she loves that old Leslie Howard movie -- "They seek him here/They seek him there/Those Frenchies seek him everywhere" -- and won't hear reason.) While he lived there, though, he developed a taste for French wine, particularly of the Bordeaux variety.

So when he got back to America, Jefferson started importing large quantities of Bordeaux from France for himself and his good buddy, George Washington. (If the Scarlet Pimpernel had been intent on smuggling all the good wine out of France, rather than the doomed aristocracy, Jen-Luc's pet theory might hold water.) According to the New Yorker article, in his first term as President, "Jefferson spent $7500 -- roughly $120,000 in today's currency -- on wine...." Can you say "pork-barrel spending"? Although in fairness, he probably didn't use taxpayer's money to stock his own private wine cellar. He did like to show off his knowledge, though, much to the dismay of certain dinner guests, like John Quincy Adams, who noted in a 1807 diary entry, "There was, as usual, a dissertation upon wines. Not very edifying."

Jefferson, at least, seemed to genuinely know something about wine. The same cannot be said, apparently, for Christopher Forbes (son of billionaire Malcolm Forbes), who in 1985 paid a whopping $157,000 for a dusty old bottle of 1787 Lafitte at a Christie's auction. At least it was purported to be a 1787 Lafitte; the bottle had no label and had supposedly been discovered "behind a bricked-up cellar wall in an old building in Paris." But it was etched with the initials "Th.J.," evidence, said Christie's Michael Broadbent, that the bottle had once been part of Jefferson's stash. That's what made it worth six figures to Forbes, who said of his purchase, "It's more fun than the opera glasses Lincoln was holding when he was shot, and we have those, too."

The problem is that the bottle was a fake, as were the other bottles in that secret stash sold to other "serious collectors." (Jen-Luc says this is code for "really rich people with more money than sense," although I would love to be able to afford some vintage scientific instruments or weaponry, for example, so I think she's being a bit harsh and over-general with her definition.) And Christie's should have known it, since Broadbent had inquired of Monticello's scholarly experts in 1985 about references to wine in Jefferson's letters. Historian Cinder Goodwin, who specialized in Jeffersonian papers, told Broadbent that neither Jefferson's daily account book, letters, bank statements or French custom forms made any mention of 1787 vintages.

Furthermore, while Jefferson had instructed that his initials be engraved on wine bottles imported from France, he used a colon ("Th:J."), not a period ("Th.J.). Her conclusion: while the bottles might be authentically 18th century, there was no specific connection with Jefferson to be found in the historical record. But per the New Yorker article, in Broadbent's eyes, "the sensory experience of consuming a bottle of wine trumped historical evidence."

Ah, such hubris! There have actually been many studies of blind taste tests using wine; in some cases, even the "experts" couldn't tell the difference between a red and white wine, never mind different varieties or vintages. The New Yorker article specifically mentions Frederic Brochet, who as a PhD student in oenology at the University of Bordeaux, conducted a study demonstrating that our perception of a "good wine" is highly influenced by whether we believe it to be expensive and of high quality beforehand.

Brochet first served his 57 subjects a moderately-priced red Bordeaux from a bottle whose label identified it as a common French table wine. The next week, he served them the exact same wine from a bottle with a label identifying it as a grand cru (a remarkably fine and expensive bottle). The participants described the first bottle as "simple," "unbalanced," and "weak," and the second bottle as "complex", "balanced," and "full." (Jen-Luc thinks they showed a pronounced lack of descriptive imagination, in addition to being fooled by the blind taste test.)

In a recent post at The Frontal Cortex, Jonah Lehrer mentions an article in Men's Vogue about a bunch of real estate moguls who get together to drink ridiculously expensive wine, often consuming as much as $30,000 worth in a single evening. (Note to those real estate moguls: I like a really nice bottle of wine with dinner as much as the next person, but if you're dropping thirty grand on wine for dinner, I don't want to hear you whining about having to pay higher taxes ever again. You could feed a family of five for a year on that.) Jonah writes in the same post about an experiment at Caltech, where 20 people sampled five different bottles of Cabernet Sauvignons identified only by their retail price, ranging from $5 to $90. In fact, there were only three different wines, so sometimes the same wine would randomly appear twice, only with a significant difference in price. And of course, the subjects invariably rated what they deemed the "more expensive" wine higher in terms of taste than the wine they thought was cheaper.

Why do we do this? Jonah has a theory about that, too. See, the participants in the Caltech study tasted their wines while inside an fMRI machine. That's the form of brain imaging that measures increased blood flow in key areas of the brain during any activity, thereby enabling researchers to see which specific parts of the brain light up during specific activities. In the Caltech study, several different brain regions were involved, but only one seemed to respond specifically to the price of the win, and not the wine itself: the orbitofrontal cortex (OFC). The OFC got way more excited by the prospect of the $90 wine than the humble $5 wine. The working hypothesis is that "the activity of this brain region shifted the preferences of the wine tasters."

In short: we are very easily fooled by subjective things like pricing and snazzy labels. That's why some of the bolder wine forgers -- and it is a burgeoning industry -- will work with genuine labeled bottles and simply refill the empties with a cheaper wine and re-cork them, confident that the "status-conscious buyer" will never taste the difference. In China, the crooks are selling fake bottles of 1982 Lafitte (an acclaimed vintage), and in 2000, Italian authorities busted several people involved in the illegal sale of 20,000 bottles of fake 1995 Sassicaia (a Tuscan red wine much in demand by serious connoisseurs). The ringleader was selling the fake wine out of the back of his Peugeot, which should have been a dead giveaway to buyers that he wasn't exactly on the up-and-up.

Wine forgery has gotten so prevalent that last year the FBI opened an investigation into the counterfeiting of old and rare vintages. It's also become something of a joke. The head of Sotheby's wine department jokes in the New Yorker article that "more 1945 Mouton was consumed on the 50th anniversary of the vintage, in 1995, than was ever produced to being with." Wealthy US and Asian consumers seem to be most status-conscious, and hence most vulnerable to fraud, but even among supposed experts, there is some fairly damning evidence that perhaps the emperor has no clothes. Via Ed Brayton, I learned that the editors of Wine Spectator inadvertently granted a prestigious award to a non-existent restaurant with a wine list featuring  overpriced bottles of what the magazine had previously panned as particularly bad wines. Hey, it could happen to anyone. (It was a very elaborate hoax, but come on -- if you haven't actually been to a restaurant and sampled its offerings, you've got no business giving it an award.)

Along with the prevalence of wine fraud, however, there is also an emerging field in wine forensics, whose practitioners are drawing more and more on a variety of physics-based analysis techniques to measure and characterize wine. For instance, French physicist Philippe Hubert devised a way to test the age of wine without opening the bottle using low-frequency gamma rays. This can tell the researcher if cesium 137 is present, an uncommon radioactive isotope that is a product of nuclear fallout. If a wine has been bottled before the beginning of atmospheric nuclear testing, it won't have any cesium 137; if it does, it is (a) not very old, and (b) given the 30-year half life of the isotope, it's possible to make a reasonably precise estimate of its age. (The technique is useless for older bottles of wine, but can help uncover obvious fraud if someone is trying to pass newer wine off as an older vintage.)

Via Physics Buzz comes word that French scientists have teamed up with a London-cased wine dealer called The Antique Wine Company to develop a new method to help authenticate wines using particle accelerators. The new technique determines the age of the glass of the wine bottle by analyzing the x-rays emitted when the bottles are zapped with ion beams, and it can make the determination without having to open to bottle or otherwise taint the wine. It turns out that vintage wine bottles have telltale "fingerprints" from the time period in which they were manufactured, so the researchers at the National Center for Scientific Research can compare their results with a database filled with information on Bordeaux-region bottles dating back to the 19th century.

The New Yorker article correctly says that "There are no scientific tests that can reliably determine the grape varietals in a bottle of wine," but there is a nifty high-tech way to determine whether a vintage bottle has gone bad or not. After all, there is nothing more embarrassing than giving a dinner party, uncorking your finest vintage, and discovering it's pretty much turned to vinegar unfit even for use as a light vinaigrette over the starter salad. Tom at Swans on Tea pointed me to a new technique using nuclear magnetic resonance spectroscopy to measure the levels of acetic acid per liter down to the tenth of a gram. Basically, a wine is considered spoiled once it hits 1.4 grams of acetic acid per liter. (Vinegar, in case you're curious, has around 12.5 grams per liter, but then, one doesn't drink it straight from the bottle, either.)

Finally, European scientists announced their prototype handheld electronic tongue last month. It's similar to an electronic nose, the latest example of electronic sensing technologies that have been developed over the last decade in an attempt to reproduce human senses using sensor arrays and pattern recognition software. An electronic nose must be trained, of course, to build up a database of samples for future reference. It can then recognize new samples by comparing those volatile compound fingerprints with those already in the database. Last year, researchers at the University of Warwick and Leicester University announced they had developed a kind of artificial snot to significantly enhance the odor-sensing capabilities of electronic noses and enable them to pick out a more diverse range of smells. Apparently our own natural nasal mucus dissolves scents and separates out different odor molecules based on when they arrive at nasal receptors. Who knew? The artificial version is a 10-micron thick layer of polymer.

But I digress. We were talking about the electronic tongue. Researchers at the University of Texas, Austin, designed an early electronic tongue ten years ago. They attached four well-known chemical sensors to a type of polymer microbeads used to synthesize DNA and its proteins, and mounted the whole shebang on a silicon wafer with carefully micromachined wells. Those wells were designed to mimic the human tongue's many cavities, which contain our test buds (nature's chemical receptors). Each microbead serves as a taste bud, via a sensor that responded to a specific chemical by changing color. For instance one turned yellow if there were high acidity. The resulting unique color combinations could be analyzed by a camera-on-a-chip connected to a computer database to analyze for several different chemical components simultaneously.

The newer handheld version of the electronic tongue was invented by Cecilia Jimenez-Jorquera and colleagues at the Barcelona Institute of Microelectronics in Spain, after wine industry specialists complained they had no quick, easy way to assess the quality of wines without having to send the bottles to a special laboratory facility.  So Jimenez-Jorquera and Company devised an electronic tongue that can identify the grape variety and vintage at the press of a button. Six different sensors detect substances associated with specific varieties of wine by measuring things like acid, sugar and alcohol. Because it's handheld, it's portable enough for use in the field. This could really be a game-changer for wine forensics. Fraudulent sellers, beware!

pretty poison

[NOTE: The Spousal Unit and I are off to Vegas for the next five days. It's book research, I swear! Well, mostly.... Here's an uber-long post to fill the gap in our absence.]

Elevators are an odd sort of public meeting space. I had an interesting exchange the other day when I stepped into an elevator with a couple of burly guys who were moving a few big boxes, and inexplicably debating the differences between the words "shiv" and "shank." One insisted they were both nouns for a makeshift stabbing weapon, while the other argued that the latter was a verb ("to shank"). (Dick Hickock, one of the murderers in Truman Capote's In Cold Blood, purportedly fashioned a shiv out of a toilet brush during his imprisonment and hid it under his mattress. It was discovered and confiscated pretty quickly.)

Without thinking, I blurted out, "Actually, 'shank' can be used as both a verb or a noun, but the more common usage is as a verb -- you know, to shank someone with a shiv." They stared at me in shock -- not so much at the interruption, but at the fact that this information came from a slim, light-haired woman in downtown Los Angeles, wearing a flowered top and sandals and carrying a bright blue patchwork handbag. Then one of them shrugged, chuckled, and said, with just a hint of condescension, "Okay, then, I guess you learned that during your last stint up the river."

Well, no: I learned that from 10 years of jujitsu in deepest, darkest, Bay Ridge, Brooklyn, where folks know their shanks from their shivs, and the Club isn't so much a deterrent for car thieves, but a popular weapon of choice. The guy was quite friendly, and he didn't call me "sweetie" or "hon," plus, I'm used to men not taking me as any kind of threat, even after I tell them about my training. Usually, they think it's cute. ("Well, she's a feisty little filly, ain't she?")

There's just something about that Y chromosome that blinds them to the reality that a woman might actually be able to hurt them. (I got around this problem in the dojo by, well, hurting them -- much to their surprise, and eventual respect. My nickname was "the headhunter.") Perhaps that's because they think aggression is all about force -- in which case, superior size and strength do become significant factors. The laws of physics are pretty clear about that. Women throughout the ages have known, however, that stealth, cunning, and a concealed weapon can be far more effective -- whether one's enemy's superior size and strength is physical, or a more intangible power advantage.

I don't fashion my own crude stabbing implements, but I do own a gorgeous, hand-forged poniard (dagger), with a small green stone set in the hilt. It's a traditional "woman's weapon": decorative, but deadly. Theoretically, one could dip the tip in a poison to make sure one's enemy didn't survive the initial stab wound. Not that I would ever do such a thing; mostly, I think it's pretty. And it reminds me of the sort of thing Lucrezia Borgia might have carried. By virtue of her gender and time period, she was pretty much doomed to limited social/political power in the lawless environment of 15th century Italy/Spain, but her name nonetheless became synonymous with corruption, infidelity, incest, and murder. Rumors about Lucrezia abound, and endure, even those lacking any historical evidence whatsoever.

My personal favorite is that she owned a hollow ring filled with poison (usually arsenic, a white tasteless odorless power first concocted by an Arab alchemist named Jabir) -- the better to poison an offending guest's drink, my dear. Street vendors used to sell cheap replicas along St. Mark's Place when I lived in NYC. (I owned one that was shaped like a spider, and used to fill it with salt and offer to sprinkle it on friends' food when dining out. Because what's the point of having a pretend poison ring if you can't use it to pretend-poison people?)

There were rumors of incest with her brother, Cesare (who had her second husband strangled), and while her third marriage proved solid enough socio-politically, both partners had numerous affairs. Yes, the poor woman was treated like chattel and married off to one husband after another to gain political advantage for the male branches of the Borgia family tree. She died at age 38, after giving birth to her eighth child. Who could blame Lucrezia if she took her power wherever she could find it?

Lucrezia was blonde, beautiful, and able to charm hostile in-laws in a pinch. But she wasn't just a pretty face. I'm sure her poisoning victims -- had one been able to ask them (and assuming the rumors are true) -- would have substantially revised their assessment of her capabilities after dining chez Borgia. Apparently, she employed both a full-time chef, and a separate, full-time poisoner. Per Wikipedia: "During the Renaissance, social climbers would commonly boast, 'I'm dining with the Borgias tonight.' A smaller number would boast, 'I dined with the Borgias last night." (Incidentally, actress Brooke Shields is a descendant of Lucrezia, so maybe all the critics who panned Lipstick Jungle might want to hire official "tasters" during meals for awhile.)

Italy seems to have boasted several such conniving femme fatales. In the 1600s, for instance, a woman named Giulia Toffana (known in some sources as Teofania D'Adamo) had a thriving household business selling a poison of her own concoction -- called aqua tofana ("Tofana water") -- to female clients throughout Palermo, Naples, and Rome. No one knows the exact formulation, but the ingredients are common enough: mostly arsenic, with a touch of lead, and perhaps even a dash of belladonna (also known as deadly nightshade, but it's significant that the name translates as "beautiful lady"). The poison was colorless, tasteless, and easily mixed with wine or water so it could be administered to the unsuspecting target during meals.

Historians estimate some 600 victims may have died from Toffana's poisonous concoction -- most of them the husbands of those aforementioned female clients. (There's a legend that Mozart was poisoned with aqua tofana, although most historians dismiss this claim outright.) Toffana was a particularly deadly sort of Renaissance feminist, who objected to the low social status of women in her culture, and their utter lack of legal rights when it came marriage (or divorce).

Eventually, one of her customers betrayed her to papal authorities, was tortured, and then executed in Rome along with her daughter and three other assistants. It might seem excessive, but Arsenic poisoning is a pretty ugly way to go. Basically, the poison inhibits certain key metabolic enzymes, and the victim ultimately dies from multiple organ failure. Before that merciful release, however, he will experience violent stomach pains, excessive vomiting (producing a greenish-yellow muck streaked with blood), diarrhea, pain when urinating, clammy sweats, convulsions, "excoriation of anus" (I don't even want to know), and delirium. Oh, and then death. Those unhappy Italian wives hated their spouses a lot. Because the symptoms so closely resembled those of cholera, arsenic poisoning often went undetected.

Arsenic has always been a popular toxin for would-be murderers. One of my favorite mystery novels is Dorothy Sayers' Strong Poison, in which the fictional Lord Peter Wimsey clears the name of a young woman, Harriet Vane, who has been accused of murdering her lover with arsenic.  Vane was a mystery writer, and had been working on a new novel involving arsenic poisoning at the time of her lover's death. Bad luck, that. In fact, she'd even purchased a tin of arsenic commonly used to poison rats as part of the "research" for her forthcoming novel.

I will not make the egregious error (this time) of spoiling the rest of the plot for curious readers. But I'd wager Sayers probably did something similar to research Strong Poison.  She may also have taken a look into the historical archives and stumbled upon the famous Lafarge murder case -- a notorious trial in France in 1840 that put the still-young science of toxicology to a crucial test. (The first use of chemical tests to detect arsenic in a legal trial occurred in 1752.)

A young woman named Mary Lafarge was accused of poisoning her husband Charles (yet another unhappy marriage). She, too, bought arsenic ostensibly to poison rates, except certain witnesses testified they'd seen her stirring a white powder into her husband's food.

But the defense challenged the methods of the medical experts -- lawyers never really change, do they? -- because the doctors hadn't used a new improved test for arsenic developed by the English chemist James March in 1836. It was a far more sensitive test, able to detect tiny trace amounts of arsenic. (Arsenic deposits can be found in the hair follicles and nails once it enters the bloodstream, for instance --  a key plot point in Strong Poison.) The tests conducted when Charles' body was exhumed were negative for arsenic. But a chemical analysis of the leftover food and various white powders Marie carelessly left about the house "contradicted the negative finding." Zut alors! What to do? Clearly the big guns were needed. So they called in Mathieu Orfila, the world's greatest expert on toxicology at the time.

They couldn't have made a better choice. Orfila literally wrote the book on toxicology (Traites des Poisons) in 1814, and labored tirelessly to make chemical analysis a routine part of forensic medicine. He studied the effects of asphyxiation, for instance, the decomposition of bodies, and developed tests to detect the presence of blood. And he made a crucial finding about exhumation: arsenic in the soil around graves could sometimes leak into the bodies, leading to an incorrect finding of poisoning. To guard against this, he developed a method for testing soil to rule out accidental contamination in all exhumation cases.

Orfila brought this hard-earned expertise to bear on the Lafarge murder trial. He performed Marsh tests on the samples taken from the body, as well as the soil around the burial site to rule out any contamination from arsenic in the soil. There were definitely traces of arsenic in the body, and it didn't come from the soil. Marie Lafarge was found guilty of murder, although her death sentence was later commuted to life in prison.

Since then, we've seen the development of the alkaloid poison test (for detecting quinine, morphine, strychnine, atropine and opium); of spectrum analysis using spectroscopes; and of ultracentrifuges to separate particles by mass, making it possible to precisely measure the molecular weights of complex proteins. In the 1950s, ultraviolet and infrared spectrometry, along with x-ray diffraction and gas chromotography, found forensic applications, and in 1966, scientists introduced Fourier-transformed infrared spectroscopy and atomic absorption spectroscopy.

Science is still giving us new ways to test chemical substances like poison and solve all kinds of unsolved mysteries -- or just to clear up some lingering rumors, like the one about Napoleon Bonaparte was poisoned by prison guards during his imprisonment at Saint Helena.  Samples of his hair did who high levels of arsenic, but, like the poison from soil leaching into exhumed bodies, it need not be the result of deliberate poisoning. Arsenic was used in lots of things, including as a pigment in some wallpapers at the time of Napoleon's death. Prolonged exposure could account for those high levels, along with the fact that his body was buried for 20 years on the island before being exhumed and moved to its final resting place.

Just this past May, physicists came to the rescue to resolve the issue once and for all. They used a small nuclear reactor at the Italian National Institute of Nuclear Physics (INFN), built to detect neutrinos for the Cryogenic Underground Observatory for Rare Events. Except instead of testing neutrinos, the scientists used the machine to study particles in Napoleon's preserved hair samples. Neutron activation established that all of the hair samples -- including the control samples -- contained traces of arsenic. While the levels were pretty high, apparently they weren't unusually so for the time: all the hair samples taken from 200 years ago had levels some 100 times higher than those taken from folks today. And there was no significant increase in those arsenic shortly before Napoleon's death, as there would have been if he'd been administered a fatal dose.

So Napoleon's guards have been exonerated by science (although who knows about that wallpaper?). The medical consensus now seems to be that he died of something less glamorous, like stomach cancer. Still, at least one historical case of suspected arsenic poisoning turned out to be true, when forensic scientists determined a few years ago that famed racehorse Phar Lap died after ingesting a massive dose of arsenic. Next they'll be telling us someone poisoned Seabiscuit, or worse -- someone shanked Mr. Ed with a shiv.

karma chimera

When I was just a wee young thing, my grade school teacher assigned us all reports on a specific animal. I got the duckbilled platypus. Can I just say? I thought my teacher was having me on at first. I mean, come on: it had a bill like a duck, a body like a beaver, and it was venomous like a snake! It could have popped right from the pages of the fantasy stories and ancient myths I devoured so regularly at that tender age. Among other tales, I was fascinated by the myth of the Chimera, a Greek fire-breathing monster described in Homer's Iliad as having a lion's head, goat's body, and serpent's tail, and the platypus seemed eerily similar in concept, if not appearance. But I dutifully did my library research -- this was pre-Internet, so we had to actually look stuff up on paper and use old-fashioned, musty card catalogs and everything -- and sure enough, the animal was very real indeed. I've had a fondness for the platypus ever since. Its very existence made the world seem that much more magical.

My old friend the platypus made for big science news this past week: scientists have just completed the full sequence of the platypus genome. It's a lazy Sunday, and I'm still mulling over all the excellent comments on my last post, so I'll let Juan Nunez-Iglesias, another New Voice from K.C. Cole's science writing class, weigh in with his own thoughts on the matter:

Last year I attended the 2007 conference on Research in Computational Molecular Biology (RECOMB) in Oakland, California. By far the most entertaining talk was given by Jennifer Marshall Graves of the Australian National University in Canberra. Graves talked about the platypus and how weird it is, not just in its appearance, but in its genetics.

For example, one of the first principles of genetics is that of independent assortment of chromosomes. We have two full copies of our genome in every cell in our bodies: one from our father, and one from our mother. Each copy consists of 23 chromosomes, separate pieces of DNA. When a germ cell divides, it splits our own double-copy genome in two and places each half into one daughter cell -- to pass on half of our genome (per offspring) to the next generation. The principle of independent assortment states that each of our 23 chromosomes has a 50% chance of ending up in one or the other daughter cell, independent of where the other 22 end up.

This principle was first formulated by Gregor Mendel in the 19th century, and has been shown to hold for every organism ever tested -- save the platypus. The platypus has 5 sex-determining chromosomes from each parent, and all its sex chromosomes stay together generation after generation. A platypus's young will inherit all the sex chromosomes from that platypus's father or from its mother. But never a mix of the two, as happens with all the other chromosomes.

Well, the weirdness doesn't stop there. Researchers announced [last week] the release of the complete sequence of the platypus genome, publicly available online. [Jen-Luc Piquant notes that this would be a fine time to create your own cloned pet platypus, boys and girls!] Down at the single-base pair level, the platypus continues to be weird. Half of its genome looks like a reptile's, half like a mammal's. It also has genes to make venom, which not surprise you after hearing the reptile thing, but... surprise! The platypus venom genes evolved independently of the reptile ones; they are completely unrelated and unique. You can read all this and much more in this excellent article in Nature News. Definitely an exciting time to study genomics.

That sounds suspiciously like a chimera-like creature at the genetic level, doesn't it? Except it isn't. Let me just say that right up front before PZ Myers gets all medieval on my ass. Seriously, PZ's frustration with the media coverage of our friend the platypus inspired him to write this terrific post explaining why the platypus is not the the same as a chimera:

"Over and over again, the newspaper lead is that the platypus is 'weird' or 'odd' or worse, they imply that the animal is a chimera.... No, no, no, a thousand times, no; this is the the wrong message.... What's interesting about the platypus is that it belongs to a lineage that separated from ours approximately 166 million years ago, deep in the Mesozoic, and it has independently lost different elements of our last common ancestor, and by comparing bits, we can get a clearer picture of what the Jurassic mammals were like, and what we contemporary mammals have gained and lost genetically over the course of evolution."

Got that? The platypus is not a chimera. Take it from someone who really knows this stuff. Okay, but do chimeras really exist? I'm so glad you asked. Certainly the mythological Greek monster isn't real, but there is a genetic anomaly that gives rise to a rare condition known as chimerism. Per Wikipedia, "A chimera is an animal that has two or more different populations of genetically distinct cells that originated in different zygotes." (Genetically distinct cells originating from the same zygote produce a related condition called mosaicism.) In humans, it's long been believed to be an exceedingly rare condition, with fewer than 40 reported cases.

One of the most famous is Lydia Fairchild, the subject of a documentary called The Twin Inside Me. She separated from her husband while pregnant with her third child, and took a DNA test to prove her husband's paternity, as required to qualify for welfare support. He was, indeed, the father, but according to the test, she wasn't the children's mother. She was taken to court for fraud. She was only exonerated when she gave birth to her third child, with a judge-ordered witness present to take blood samples from mother and infant for testing. And those DNA tests revealed she wasn't the mother of that child either. Except she was. I mean, court-appointed eye witnesses watched her give birth. If she was a fraud, she was a damned good one, on a par with the world's best illusionists. 

A similar thing happened (without the charges of fraud) to Karen Keegan in 1998, a Boston-area teacher who needed a kidney transplant. She had three grown sons who were tested to see if they could be donors, but the DNA showed that two of them weren't her biological children. This time doctors did additional testing on Keegan, drawing samples from other areas of the body, and discovered she had two sets of cell lines with two separate sets of chromosomes -- a mix of two individuals, fraternal twin sisters who fused in the womb and developed into a single infant. Fairchild's lawyers heard about the case, and arranged for their client to undergo more testing as well. She, too, turned out to be a chimera. For instance, the DNA in Fairchild's skin and hair didn't match that of her children, but the DNA from her cervix did.

Now that's weird -- weird enough to inspire episodes of both House and C.S.I. In "Cane and Abel," House treats a young boy who suffers from seizures and believes he was abducted by aliens; the hallucinations turn out to be caused by the "alien" brain tissue from the twin brother who had merged with the boy in the womb. The C.S.I. episode ("Bloodlines") involved a rape victim who correctly identifies her attacker, only to have him exonerated by DNA evidence, although it demonstrated her rapist was related to the original suspect, who had many brothers -- none of whom proved to be a positive match. The suspect turns out to be a chimera: two different sets of DNA. Grissom discovers the suspect's unique condition when he notices visible Blaschko's lines while photographing said suspect's torso for evidence.

Bizarre though it sounds, according to this 2003 article in New Scientist, chimerism might not be as rare as previously believed; in fact, some researchers are beginning to think there might be a little bit of the chimera in all of us. Most cases simply aren't detected. Usually, there aren't many outward signs or symptoms: eyes of slightly different coloration, for example, hair growing differently on opposite sides of the body, even hermaphroditism (having both male and female genitalia -- the subject of another memorable House episode in which a beautiful young female model turned out to have testicular cancer). Male tortoiseshell tabbies are examples of chimerism. It takes a DNA test to reveal the chimerism, and usually more than one, with samples taken from different parts of the body.

A more common variant is blood chimerism, when fraternal twins share part of the same placenta and exchange blood, which settles in the bone marrow, so each twin is genetically separate -- except for their blood which has two distinct sets of genes and two distinct blood times. Some 8% of fraternal twins are blood chimerism, and the number could rise given the increase in multiple births, thanks to in vitro fertilization. Fairchild and Keegan are much rarer cases.

Of course, it was only a matter of time before scientists started creating chimeras in the lab -- yes, just like the infamous South Park episode where the local mad scientist created creatures with multiple derrieres. Okay, not like that, but in 1984 scientist combined a embryos from a goat and sheep to form a "geep." Others have made rat/mouse and rabbit/human chimeras (2003), as well as pigs with human blood flowing through their bodies. Most were created not with the intention of creating living hybrids, but for the purpose of harvesting stem cells for further research. And in 2007, scientists at the University of Nevada's School of Medicine created a sheep with 15% human cells. In the UK, researchers are attempting to insert human DNA into a cow's egg using the same technique that successfully cloned Dolly the Sheep. Last I heard, they hadn't yet succeeded.

Sheesh. Truth really is stranger than fiction sometimes. A creature from Greek mythology has a counterpart in modern 21st genetics. Next scientists will be telling us that vampires and werewolves are real. Which means we might be in need of a Slayer or two. Any takers?

crime scene craziness

Last year, the Spousal Unit and I attended a friend's 40th birthday party here in Los Angeles. Among the many guests was one of the writers for Bones -- one of my favorite current TV shows, as regular readers may know. We exchanged the usual pleasantries, I said how much I liked the show, and then he asked what I did for a living. As soon as I said "science writer," he tensed up, with a slightly panicked, hunted look in his eye, and launched into a litany of his supposed "sins against science": "I know, I know, we take liberties with the science, DNA testing can't be done in just a few hours, Angela's holographic system for recreating faces doesn't exist...." I quickly interrupted his impromptu "confessional" to assure him I wasn't one of those sorts who constantly feel compelled to nitpick science-themed fictional TV shows for --basically -- not being science-themed documentaries.

Personally, I think it's quite telling, and more than a little sad, that this man's first reaction to encountering a science-oriented person (even one who admitted to being a Bones fan) was to recoil and start defending himself. I can only imagine how often he's encountered such individuals who dispensed with the usual pleasantries and simply attacked him for doing his job: producing a compelling, entertaining crime drama. It reflects quite poorly on scientists, frankly. Scientists mean well, but all the  judgmental finger-wagging gets pretty old, pretty darn fast. And soon, they're just not being heard because people have stopped listening. Who likes to be nagged and nitpicked all the time? Would it kill the scientific community to hand out a few kudos once in awhile, to offset the constant griping?

So in today's monster blog post, I come not to bury science-themed TV shows (death by nitpicking?) but to praise them -- specifically, to praise Thursday night's new episode of C.S.I., or, as Jen-Luc Piquant has dubbed it, "the episode that launched a thousand Google searches." Maybe it was because of May Sweeps, or perhaps the whole writing staff got exposed to laughing gas that made them collectively giddy, but the episode ("The Theory of Everything") managed to cram together a record number of weird, stranger than fiction forensic oddities. (The writers of House are probably seething with envy; extremely rare and bizarre medical anomalies are their stock in trade.) And as I discovered when I Googled the relevant terms, they're all pretty solidly based on scientific fact. [SPOILER ALERT! The rest of this post gives away key plot points -- solely in the interests of science -- so if you didn't catch the episode, you might want to hold off reading further until you've checked it out: it's available on the CBS official Website.]

We get an inkling of the craziness to come in the opening sequence, set in the Vegas police station, where Detective Brass is questioning a suspect while, in the main room, a mentally disturbed homeless woman named Evelyn expounds on string theory and the coming alien invasion. We quickly discover that the suspect is in jail for killing a deer with a bolt from a cross bow and, um, putting a dress on it. He's recently divorced, drunk as a skunk (blood alcohol level of 2.8!), and suddenly makes a break for it, bolting through the station until he's cornered. The assembled officers use pepper spray to subdue him, but he's too smashed for it to have much effect. So Brass gives the order to tase him, using the unfortunate phrase, "Light him up." As if on cue, the suspect bursts into flames. Soon he joins the dead deer in the morgue for autopsy, and Brass is taking heat for having a suspect die in custody.

First, a brief word about tasers. I tend to think of them in terms of those smaller handheld electroshock devices, but the kind more commonly used by law enforcement -- and depicted in the episode -- are a bit more complicated. A taser fires two small darts (electrodes) connected to the main unit by conductive wire, with a maximum range of about 35 feet. The darts are pointed to penetrate clothing and touch the skin. Earlier models required them to pierce the skin, but today's version uses a "shaped pulse" that is more effective in penetrating clothing. The handheld devices are more commonly marketed to the general public these days. In fact, Jen-Luc Piquant was thrilled to discover a surprisingly large number of pretty pink tasers for women, from a standard issue model, to a taser disguised as a couple of pink tampons, to this adorable pink seal taser -- and yes, it was made in Japan, along with the infamous Hello Kitty "personal massage wand." (Think I'm kidding? Think again! A Hello Kitty taser is practically inevitable.) Jen-Luc totally covets her own pink seal taser.

Anyway, tasers, or stun guns, are fairly controversial, since there have been several cases of suspects dying, ostensibly as a result of being tased -- the most recent case was last year, involving a Polish immigrant in Canada who died after being tased by police in Vancouver's airport. That man didn't burst into flames, however. Combustion isn't typically one of the risks. Nick Stokes figures it has to be either the moonshine the man had been consuming, the pepper spray, or some chemical in the man's shirt, but a controlled experiment involving three Jell-O Men shows that none of those could account for the poor man's sudden immolation.

Eventually, Stokes discovers that there is more than one type of pepper spray. This is quite true. All types contain the same active ingredient: capsaicin, a chemical derived from the fruit of plants like chilis. But the episode is correct that the sort used by the police is water-based and hence non-flammable -- precisely because of the growing use of tasers by police officers. Some consumer brands have alcohol-based propellants, however, which are highly flammable.

In the case of Burning Man, the officer at fault had used a consumer version after his girlfriend accidentally took his pepper spray with her to work. Nick repeats the experiment with the other type of pepper spray, and voila! The Jell-O Man bursts into flame. And yes, that was the Mythbusters looking on approvingly from behind the glass as Nick performs his final test -- an uncredited cameo to keep obsessive fans happy. (Obsessive? Moi? Jen-Luc is the one who writes Mythbuster-themed slash fanfic. And if that doesn't take you to a scary mental place, I shudder to think what it would take to do so.)

Really, that's weird enough for one episode right there, but when  police finally track down the unfortunate Evelyn, she's dead, the victim of a collision with a semi. The truck driver was temporarily blinded by the sun reflecting off her tinfoil costume, and didn't even see her. The clincher: she's bleeding green blood -- yes, just like Mr. Spock; perhaps she really was in touch with aliens. (Or not; certain species of lizards known as skinks also have green blood, along with some marine worms.) The whole green blood thing turns out to be a mini-epidemic: two more victims soon show up: another homeless man, dead from blunt force trauma to the head, and his killer: a pest control specialist named David Bohr, a.k.a. "Atomic Dave" (one of several cheeky nods to physics).

Bohr is alive when they find him, but not for long: he soon starts seizing and the same green blood, um, oozes out of his face. He joins the other victims in the county morgue, where we have the added twist of all his internal organs being various shades of green, including his brain. It turns out that all the green blood victims suffered from migraines and were taking massive doses of a medication without a prescription -- supplied by Bohr the exterminator, who was taking the stuff himself in enormous quantities. Except Bohr thought he was suffering from migraines, when in fact, he had a massive brain tumor -- hence the headaches, crazed behavior, and hemorrhaging. That's the danger of self-medication: what if your original diagnosis is wrong?

Hodges and Wendy (who is emerging as his unlikely love interest) conclude -- along with Grissom -- that the culprit is high levels of sulphur in the blood, caused by the large doses of migraine medication the victims had been taking. (The drug is identified as thiocyte, but this might be a fictional version -- perhaps for legal reasons? -- since the only Google hits that showed up on that drug name were related to this particular episode of C.S.I.) And naturally, they invoke Mr. Spock, although Wendy rightly reports that Spock's green blood, according to the series, arose from copper instead of iron in the hemoglobin. She knows a whole bunch else about Star Trek, as it happens, prompting Hodges to observe, "You're like a geeky nerdy guy trapped in a woman's body." Not to be outdone, Wendy zings back, "So are you."  Yeah, those two are made for each other....

This "Vulcan Blood" phenomenon isn't fictional. In fact, it's ripped right from last year's science headlines, when an article appeared in The Lancet describing a very odd case of a 42-year-old Canadian man (why are they always Canadian?) who appeared to have dark-green blood coursing through his arteries. The case was already a bit strange before the whole Vulcan-blood thing. The patient had fallen asleep in a chair for so long, and in such a position, as to severely restrict the blood flow to his limbs, resulting in localized tissue and nerve damage that required surgery to correct, before he lost his legs. The man also suffered from chronic migraines and had been prescribed sumatriptan to treat them. Apparently he'd been consuming a whopping 200 milligrams of the stuff per day, giving rise to a rare condition called sulfhaemoglobinaemia, in which high levels of sulphur wind up up in the oxygen-carrying compound hemoglobin, found in red blood cells. 

Meanwhile, Catherine Willows gets called to a nearby home where a 60-something couple has been found dead in their sleep. The husband was a physics professor, and they named their cat Schroedinger -- except poor Schroedinger in this case isn't in a superposition of states, but very much dead and buried in the back yard, which is littered with the bodies of dead squirrels.

Initially, Willows surmises the exterminator's equipment -- which employs electromagnetic pulses to chase away the squirrels -- interfered with the couple's matching pacemakers, but lab tests definitively rule that out: the pulses were too weak to have any effect on the pacemakers' operation. It's a very real health risk, however: most Websites concerned with pacemakers warn those considering the surgery to avoid MRIs altogether afterward, and use with caution such devices as cell phones, iPods microwave ovens, metal detectors, industrial welders, and electrical generators.

A tox screen reveals that both the squirrels and the couple died of cyanide poisoning, the squirrels via ingested pellets, and the couple by inhaling a hydrogen cyanide gas. Victims of foul play? Yes for the squirrels; the jewelry-maker next door admitted to using cyanide in her electroplating (a common application for cyanide) and dosing the pesky squirrels (not to mention the unfortunate Schroedinger, by accident), but as for the elderly couple -- not so much. Turns out the cyanide that killed them came from the old carpet -- since overlaid with a new one -- which contained polyvinyl chloride as a flame retardant. A fire broke out when a fleeing squirrel chewed through some electrical wiring, the old carpet kept things to a low smolder and the chemicals in the carpet fibers, when burnt, produced hydrogen cyanide gas. At least the couple died peacefully in their sleep.

All of the above is pretty scientifically accurate, give or take the occasional liberty for Purposes of the Plot -- at least as far as I could tell from my hour of Googling. If one were going to nitpick on the cyanide front, one might note that Hodges is credited with the rare gift of being able to smell the bitter almond odor associated with hydrogen cyanide. It's true that not everyone can do so, but those that can't are in a minority (one out of four). Three out of four people can detect the telltale odor; if anything, it's surprising that Hodges is the only person in the Vegas lab who can do so. Then again, Hodges is known for exaggerating his gifts, so constantly proclaiming the uniqueness of his ability is entirely in keeping with his character.

Recapping the day, the C.S.I. team marvels at the unlikely string of coincidences that connected the various cases. First, a suspect goes up in flames while in police custody, and the last person he came into contact with -- Tinfoil Evelyn -- ends up dead and oozing weird green blood from migraine medication she'd copped from Atomic Dave, hired by the elderly couple to get rid of the squirrels. The late, great Immolated Deer-Killer turns out to be the ex-husband of the couple's next-door neighbor. The Deer Killer only ended up in police custody (and thus, dead) because he was so upset about the end of his relationship with the jewelry maker. Grissom says there's no such thing as coincidences and attributes the phenomenon to (wait for it!) string theory -- thereby tying him to crazy Tinfoil Evelyn.

Okay, citing string theory as an explanation for a series of unlikely coincidences is stretching things very far indeed -- in fact, unlikely coincidences do arise quite frequently, and they are rarely (if ever) evidence of anything more than that. But the brief layperson's sound-bite summation that Grissom gives of the essence of string theory is dead-on. The writers did their due diligence, even if they added their own fanciful metaphorical embellishment. And that's good enough for me.

burn, baby, burn

It's only a matter of time before C.S.I. and its various spinoffs warrant their own channel, along with the Law and Order franchise. Until then, one can always catch a few repeat episodes in the evenings on Spike TV, provided one can stomach the lowest-common-denominator commercials. (General theme: men are crude, slovenly pigs, and durned proud of it. Jen-Luc Piquant is offended on behalf of every intelligent, enlightened man of her acquaintance -- and she is acquainted with several.) On the plus side, the channel airs the Vegas-centric original C.S.I., which raises the level quite a bit, so perhaps there's hope yet for the programming folks at Spike TV. Sometimes I like to unwind after my gym workout with an episode or two, particularly if the Spousal Unit isn't home yet. One of my favorites is an episode with an intriguing subplot: a potential case of spontaneous human combustion (SHC).

An elderly woman is found burned almost to ashes in her living room, dressed in what is left of her nightgown, save for her ankles and feet, which remained unburnt -- along with the rest of the room. The investigating CSIs assume there was an ignition source of some kind, most likely a cigarette, but Sarah Sidle finds herself suspecting it might be SHC, in part because she can't quite believe that anything else could reduce the body to that level of ash without burning down the entire building. The human body isn't especially flammable, she reasons, and has high water content. Surely the fire would be doused rather quickly even if the body did manage to catch fire. That's why it takes flames of around 1600 degrees Fahrenheit over two hours or more to cremate human remains. A cigarette tip, in contrast, only burns at around 700 degrees Celsius. With the help of her colleague, Nick Stokes, she performs an experiment with a dead pig in their headquarters parking lot, wrapped in an identical nightgown, with a single lit cigarette placed in the nightgown. The nightgown catches, and begins a slow, steady burn. Hours later, the pig, too, has been reduced to ash, save for its hoof-y extremities.

Sarah bows to the science and abandons her SHC theory, just as Grissom stops by and informs then that the phenomenon is known as the wick effect. (Yes, he'd known all along it wasn't SHC; he just wanted Sarah to do the experiment and see for herself. Science in action!) The old woman's body fat served as a fuel source for the slow burn from the cigarette, with the nightgown serving as the wick. As the body burned, the melting fat seeped into the clothing, and the long chains of hydrocarbons that make up human fat provided the energy to consume the body -- locally, without damaging (much) the surroundings. Eventually the "candle" burns out.

Sarah and Nick's impromptu experiment mimics a 1998 experiment conducted by Dr. John de Haan of the California Criminalistic Institute for the BBC TV science program QED. De Haan took a dead pig, wrapped it in a blanket and placed it in a furnished room, then set fire to the blanket with nothing but a match and a bit of gasoline. (Pig flesh is the closest to human flesh, so pigs are frequently used in these sorts of experiments.)  It took awhile for the pig body to catch fire -- Sarah was correct that the body isn't highly flammable - but once it caught, it burned at a high temperature and low flame, burning for several hours until de Haan extinguished the fire. The flesh and bones in the burned part of the body were reduced to ashes, but there was almost no damage to the rest of the room -- except for a melted TV set. De Haan reported that the heat from the burning body collected at the top of the room, making it hot enough to melt the appliance.

There has never been a definitively proven case of SHC, although -- as with any such mysterious phenomenon -- there are a handful of "true believers" out there, along with the usual skeptics. There have been some odd occurrences which initially seemed to point to SHC. For instance, in 1965, there was a case of an 85-year-old woman who died of a heart attack in her home, landing head-first in the hearth of an open coal fire. Both arms and her left leg were burned to ashes, but her right foot was intact. Internally, there was far less damage, enough for the autopsy to reveal that she had died from a heart attack, not from the burns.

Perhaps the most famous case is that of Helen Conway, an elderly woman, overweight, and an inveterate smoker who burned while sitting in an upholstered chair in her bedroom. The fire chief who responded believed it only took 21 minutes for the body to burn, convinced it was SHC. The wick effect doesn't work that fast, of course, but others have speculated that the woman's body fat may have given rise to a much more intense fire, akin to a grease fire common to commercial kitchens. Apparently, while one of the firemen was searching for the victim's remains in the smoky bedroom, he stuck his hand in "something greasy" that turned out to be the remains. So who knows? The grease fire effect might be plausible.

De Haan himself encountered an interesting case in 1991, when two hikers near Medford, Oregon, found the still-burning body of a "well-nourished" (i.e., overweight) dead woman face down in the leaves. Cause of death was multiple stab wounds; apparently her killer had set fire to the body using barbecue starter fluid, hoping it would destroy the evidence. The woman's pelvis and spine were reduced to ash, as was most of the torso. Police caught the murderer, who confessed and said he'd set the body on fire 13 hours before the hikers discovered it. De Haan reasoned that the combination of "an immobile clothed body with a high fat-to-muscle ratio, accelerant, and artificial ignition" created perfect conditions for the wick effect -- hence the slow burn.

There's plenty of other documented cases of strangely burnt (or partially burnt) bodies, which is why belief in SHC prevails even today. Heck, Charles Dickens attributed the death of a heavy drinking character in Bleak House to SHC, because at the time, it was believed that heavy drinking could cause self-combustion. It was a moral thing, not founded in solid science, but Dickens drew on two actual cases he'd encountered in a collection of stories by Jonas Dupont published in 1763, under the title De Incendis Corporis Humani Spontaneis. The tales include one of a drunken German who supposedly self-ignited after drinking a great deal of brandy.

Alternative theories can sometimes be a bit, um, far-fetched, at least to those well-versed in the sciences. A man named John Heymer wrote a book called The Entrancing Flame in 1996, in which he advanced his hypothesis that SHC victims are loners who fall into a strange kind of trance that triggers a chain reaction of "mitochrondrial explosions" by "freeing hydrogen and oxygen within the body." That hypothesis might make sense if hydrogen and oxygen actually existed in gas form inside a mitochrondrial cell, but they don't -- and a good thing, too, otherwise the very act of inhaling could cause spontaneous ignition.

Even more far-fetched is the take of a man named Larry Arnold, who thinks that occasionally human cells get hit by a mysterious particle -- he calls it a "pyrotron" -- that causes a nuclear chain reaction inside the body. We give Arnold points for creativity and coming with a really cool moniker for his imaginary new particle. A "pyrotron" sounds really cool, much cooler than his alternative hypothesis that too much stress causes folks to burst into flame. Alas, it does not exist. At least Arnold doesn't try to attribute SHC to geomagnetism or kundalini yoga. Seriously. Yoga has many potential health benefits, but I doubt that even if it could (as some practitioners claim) heat the body -- which frankly happens with any kind of exercise (yoga is actually quite intense when practiced correctly) -- it wouldn't cause us to burst into flame.

A slightly more plausible alternative explanation is that clothing in these cases catches fire because of a discharge of a large amount of accumulated static electricity. This is the pet theory of Robin Beach, founder of a scientific detective agency in Brooklyn, New York. (We like the idea of a scientific detective agency, in principle -- talk about a great TV series concept!) One of Beach's early cases involved a young woman working at a factory plagued by as many as eight small fires every day -- caused by the fact that she retained more electric charge than the average person. Walking on carpets during dry winter weather can cause anyone to build up an electrostatic charge as high as 20,000 volts -- usually discharged the minute we touch a doorknob or other metal surface. Beach's take is that certain people retain even higher electrostatic charges and sometimes these cause give rise to small fires.

The problem with applying Beach's theory to SHC is that alleged SHC cases claim the victims are burned from within -- and no electrical discharge has been shown to cause anything remotely like that effect. Also, while the bodies are consumed, the surroundings are not in claimed SHC cases; a fire caused by electrostatic charge would cause damage to surrounding objects. So I'll stick with the Wick Effect for the time being as my preferred rational explanation, even though the jury's still out on some of the stranger cases, where the Wick Effect really doesn't apply. I'm willing to bet scientists will figure it out one day. They won't convince the diehard True Believers, but perhaps the answer will supply an interesting plot line for a TV show of the future.