One Day, a Machine Will Smell Whether You’re Sick – The New York Times

Sniffing disease markers is a fundamentally promising concept. We know that dogs have very good smell, so that is an existence proof that something interesting can be detected in the air. (In my family’s experience, human smell can also become amazingly good, at least for pregnant women!) In fact, if B.F. Skinner were still alive, I wonder if he would be training pigeons to sniff out disease?

But although air is feasible, it does seem like blood is a better choice because it is likely to have stronger signals and lower noise. Air-based sensors would be non-invasive, so perhaps that is why some groups are pursuing air.

…a team of researchers from the ..Monell Chemical Senses Center and the University of Pennsylvania [are working] on a prototype odor sensor that detects ovarian cancer in samples of blood plasma.

The team chose plasma because it is somewhat less likely than breath or urine to be corrupted by confounding factors like diet or environmental chemicals, including cleaning products or pollution. Instead of ligands, their sensors rely on snippets of single-strand DNA to do the work of latching onto odor particles.

“We are trying to make the device work the way we understand mammalian olfaction works,” … “DNA gives unique characteristics for this process.”

Judging by research at UCSD and elsewhere, I envision tests like this eventually be run as add-on modules to smartphones. Buy a module for $100 (single molecule, home use) up to $5000 (multiple molecules, ambulance use), and plug it into your phone. Above $5000, you will probably use a dedicated electronics package. But that package might be based on Android OS.

This is also another example of Big Data science. It could be done before, but it will be a lot easier now. Blood collected for other purposes from “known sick” patients could be used to create a 50,000 person training set. (The biggest problem might be getting informed consent.)


Art to Science: in making whiskey barrels

Whiskey is aged in oak barrels, and oak wood is highly variable. But barrel-making can still become much more scientific.

“Twenty-five years ago, it was more art than science. Now we have a healthy dose of science in with the art.” Larry Combs, the general manager for Jack Daniel’s

Recently, the two companies completed the decade-long Single Oak Project, in which they made 192 barrels, each using the wood from a single log, to find what constituted the “perfect” bourbon. (Among other things, they found that wood from the bottom of a tree made for the best aging.). Computers track each stave as it moves through assembly, while sensors analyze staves for density and moisture content. Instead of guessing how much to toast a barrel, operators use lasers and infrared cameras to monitor the temperature of the wood and the precise chemical signature that the heat coaxes to the surface — all subject to the customer’s desired flavor profile.“They’ve developed technologies so that if we say we want coconut flavors, they can apply this or that process” — like applying precise amounts of heat to different parts of the wood to tease out certain flavors — “and we’ll have it,” said Charles de Pottere, the director of production and planning at Jackson Family Wines…

… Black Swan makes barrels with a honeycomb design etched on the inside, which increases surface area and reduces a whiskey’s aging time.

Their approach: learn by experimentation, and use the new knowledge for tight process control. Same approach as machining, aviation, …. And this is a 400+ year old industry. Now I just need a word that’s better than “science” to describe this approach. (See my previous post.)

Last comment: according to the article, one of the main forces driving willingness to learn was competition from superior French barrels.

Source: Packing Technology Into the Timeless Barrel – The New York Times

Drones Hunt Down Poachers in South Africa | Flying Magazine

The Lindbergh Foundation’s Air Shepherd initiative uses drones to catch poachers in South Africa.

My comment: Flying at night, up to 40km away, is technically difficult. But smart autopilots, using GPS and accelerometers, mean that the operators (pilots) don’t have to do hands-on flying except landing and takeoff.  Probably every component in the system except the ground vehicles is hobbyist level, although some of the specialized long-range radio gear might need to be hand built.  Nothing from aerospace companies.  Battery powered, so essentially noiseless. Also, the aircraft itself is the cheapest part of the system.

The article mentions flights of “up to 4 hours.” That is a very long duration, and would require lots of batteries. 2 hours or even less sounds more realistic. Efficient cruising speed is probably is probably around 40 kph (25 mph). If anyone finds other discussions of this project, please let me know.

Source: Drones Hunt Down Poachers in South Africa | Flying Magazine

Self-driving cars may take decades to prove safety: Not so.

Proving self-driving cars are safe could take up to hundreds of years under the current testing regime, a new Rand Corporation study claims. Source: Self-driving cars may not be proven safe for decades: report  The statistical analysis in this paper looks fine, but the problem is even worse for aircraft (since they are far safer per mile than autos.) Yet new aircraft are sold after approx 3 years of testing, and less than 1 million miles flown. How?

From the report:

we will show that fully autonomous vehicles would have to be driven hundreds of millions of miles and sometimes hundreds of billions of miles to demonstrate their reliability in terms of fatalities and injuries. Under even aggressive testing assumptions, existing  fleets would take tens and sometimes hundreds of years to drive these miles.

How does the airline industry get around the analogous statistics? By understanding how aircraft fail, and designing/testing for those specific issues, with carefully calculated specification limits. They don’t just fly around, waiting for the autopilot to fail!

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Is the FDA Too Conservative or Too Aggressive?

I have long argued that the FDA has an incentive to delay the introduction of new drugs because approving a bad drug (Type I error) has more severe consequences for the FDA than does failing to approve a good drug (Type II […]

Source: Is the FDA Too Conservative or Too Aggressive?

My take: this paper by  Vahid Montazerhodjat and Andrew Lo is interesting, but it only looks at one issue, and there are many other problems that make overapproval more likely. There are many  biases in the drug pipeline and FDA approval process, most of which are heavily in favor of approving drugs that do nothing (and yet, still have side effects). To mention one of many, the population used to test drugs is younger, healthier, more homogeneous, and more compliant than the population that ends up actually taking the drug. A second bias is that the testing process screens out people who have major side effects – they stop taking the drug, and are dropped from the sample (and from the statistical analysis at the end). So we only see the people with moderate or no side effects. Both of these problems lead to biases, which better statistical methods cannot remove.

The paper is interesting, but it is working from an idealized model of the drug research process, and I would not take its quantitative results seriously. The basic logic seems sound, though: there should be different approval standards for different diseases.

Using data mining to ban trolls on League of Legends

Something I just found for my Big Data class.

Riot rolls out automated, instant bans for League of Legends trolls

Machine learning system aims to remove problem players “within 15 minutes.”

An interesting thread of player comments has a good discussion of potential problems with automated bans. Only time will tell how well the company develops the system to get around these issues.

This company also took an experimental approach to banning players. And hired 3 PhDs in Cognitive Science to develop it. (Just to be clear, their experiments did not appear to be automated A/B style experiments.) After the jump is a screen shot from that system.

League of Legends screen shot

But, I’m not tempted to play League of Legends to study player behavior and experiment with getting banned! (I don’t think I’ve ever tried an MMO beyond some prototypes 15 years ago.)  If any players want to post your observations here, great.

When the doctor’s away, the patient is more likely to survive | Ars Technica

When the doctor’s away, the patient is more likely to survive | Ars Technica.

Very surprising. When cardiologists are away from the hospital, deaths after heart failure or cardiac arrest declined. I’ll probably use this in my course this Spring. (Or perhaps in both courses: Big Data, and Operations Quality in Healthcare.)

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