science

Plant geneticists say they have discovered an answer to a near-universal question: Why are tomatoes usually so tasteless?

Yes, they are often picked green and shipped long distances. Often they are refrigerated, which destroys their flavor and texture. But now researchers have discovered a genetic reason that diminishes a tomato’s flavor even if the fruit is picked ripe and coddled.

The unexpected culprit is a gene mutation that occurred by chance and that was discovered by tomato breeders. It was deliberately bred into almost all tomatoes because it conferred an advantage: It made them a uniform luscious scarlet when ripe.

Now, in a paper published in the journal Science, researchers report that the very gene that was inactivated by that mutation plays an important role in producing the sugar and aromas that are the essence of a fragrant, flavorful tomato. And these findings provide a road map for plant breeders to make better-tasting, evenly red tomatoes.

That’s from the NYT (via Razib Khan who digs up the original study).

One of my favorite celebrity chefs recommends using canned tomatoes from Italy for cooking because ‘fresh’ tomatoes grown in North America are completely tasteless. Soon to change!

One aspect of fever I harp on year after year and where I am continually ignored is the importance of not treating a fever. It is estimated that the fever response is 400 million years old. How do they know that? Got me. Most molecular techniques are “sufficiently advanced technology indistinguishable” from magic; all I know is that they were not measuring core body in T. rex. Every creature that can make a fever will make a fever when infected. All branches of the immune system function better at 102 than 98.2 (yes, 98.2), but in the calorie poor environment most creatures live in, if we maintained our core temp at 102 we would all starve to death. It is also quite remarkable how many potential pathogens cannot grow at 98.2, much less 102. Being above ambient temperature protects against thousands of molds and bacteria.

That’s SBM. The post is actually concerned with breathing, another automatic impulse, and one that has attracted crackpots looking to fail the tests of crackpot science.

According to the label, its ingredients are:

• Niacin 30 mg — 150% of the RDA
• Vitamin B6 40 mg — 2000% of the RDA
• Folic acid 400 mg — 100% of the RDA
• Vitamin B12  500 mcg — 8333% of the RDA
• Energy blend: taurine, glucuronic acid, malic acid, N-acetyl L tyrosine, L-phenylalanine, caffeine, and citicoline. Total amount of blend: 1870 mg. The caffeine content is not specified on the label, but it is supposedly comparable to a cup of the leading premium coffee.

It contains only 4 calories, with no sugar.

and later:

How Did They Choose This Mixture of Ingredients?

I asked the company that question and did not get a response. There doesn’t seem to be any rationale for anything but the caffeine, and certainly no rationale for the specific amounts of each ingredient.

More here. The conclusion? No better than a cup of coffee.

But now we are learning that while the placebo itself is inert, the act of giving a placebo is not: it can produce actual physiological effects through suggestion and expectation.

That’s from SBM. It’s easy for scientifically-minded people to scoff at placebos, which are pure evil to any card-carrying physics-evnying PhD. How do you control and test the effect of the communication/empathy skills of a practitioner? How about status or charisma? Can’t, so no point in talking about it.

That needlessly cedes ground to charlatans and worse, though. The human body is a pretty awesome drugstore. It’s one where the shelves are shrouded and nobody knows how to pay, but we should pay attention to it:

the take-home message for clinicians, for physicians, for all health professionals is that their words, behaviors, attitudes are very important, and move a lot of molecules in the patient’s brain. So, what they say, what they do in routine clinical practice is very, very important, because the brain of the patient changes sometimes… there is a reduction in anxiety; but we know that there is a real change…in the patient’s brain which is due to… the ‘ritual of the therapeutic act.’

Why not train doctors to be better at delivery? The SBM post frames this as a conversation about ethics, but I don’t think you need to go there. As pointed out in this post, there are a lot of different kinds of placebo effects and not all of them require lying to patients.

SBM agrees on that point, at least:

I think attempts to elicit a placebo effect should be only used in conjunction with an effective treatment. Words should be used carefully, and the focus should be on general measures that bolster the doctor/patient relationship and enhance the patient’s trust, like spending more time with the patient and showing a greater interest and sympathy.

Anyway, let’s talk about the liars.

Is it ok to lie to someone if it’s genuinely in their interest? Amazing as it is to say, this is an ethical problem that needs to be resolved to advance science (here is another one!).

I’d argue that it is a good idea, but proving that it’s in their interest is a really messy empirical question.

Here is what a placebo balanced trial looks like:

Dr. Benedetti is using “placebo balanced design” to tease out the influence of verbal suggestions — expectations — on the action of drugs. Subjects are divided into four groups. The first group of subjects receives the active treatment and is told it is the active treatment (the truth).  The second group receives the active treatment and is told it is placebo (a lie). The third group receives placebo and is told it is the active treatment (a lie). The fourth group receives placebo and is told it is placebo (the truth).

Not good enough, in my mind. You’ll need ANOTHER level of testing where you tell one group that you’ll be lying to some people. In the real world, patients would know placebos are fair game and so controlling that feedback loop is important, too.

And even then, some doctors will be better faith healers than others and so just get better outcomes. Bottle that!

NYT on some recent reserach:

Now it turns out that existing models of the core, for all their drama, may not be dramatic enough. Reporting recently in the journal Nature, Dario Alfè of University College London and his colleagues presented evidence that iron in the outer layers of the core is frittering away heat through the wasteful process called conduction at two to three times the rate of previous estimates.

The theoretical consequences of this discrepancy are far-reaching. The scientists say something else must be going on in Earth’s depths to account for the missing thermal energy in their calculations. They and others offer these possibilities:

• The core holds a much bigger stash of radioactive material than anyone had suspected, and its decay is giving off heat.
• The iron of the innermost core is solidifying at a startlingly fast clip and releasing the latent heat of crystallization in the process.
• The chemical interactions among the iron alloys of the core and the rocky silicates of the overlying mantle are much fiercer and more energetic than previously believed.
• Or something novel and bizarre is going on, as yet undetermined.

Obviously not much I can add, except some general geekery. Here’s the photo we all saw in high school.

We can thank the iron catastrophe for the core’s existence, which, by the way, produces the magnetosphere and protects us from cosmic rays.

Here’s a cool image of that with all kinds of sci-fi sounding terminology.

But don’t get all cocky, now, Ethan Siegel reports on how a super villain might overcome the magnetosphere and destroy the world!

Bryan Caplan, I think, coined the “Ideological Turing Test”, which is a neat idea. Tyler Cowen likes it, too.

Put me and five random liberal social science Ph.D.s in a chat room.  Let liberal readers ask questions for an hour, then vote on who isn’t really a liberal.  Then put Krugman and five random libertarian social science Ph.D.s in a chat room.  Let libertarian readers ask questions for an hour, then vote on who isn’t really a libertarian.  Simple as that.

My challenge: Nail down the logistics, and I’ll happily bet money that I fool more voters than Krugman.  Indeed, I’ll happily bet that any libertarian with a Ph.D. from a top-10 social science program can fool more voters than Krugman.  We learn his worldview as part of the curriculum.  He learns ours in his spare time – if he chooses to spare it.

We learn from Psyblog, though, that:

Janis and King (1954) tested this by having some participants give a talk while two others listened. Then they swapped around and one of the passive listeners gave a talk to the other two on a different topic.

What emerged was that, on average, people were more convinced by the talk when they gave it themselves than when they merely heard it passively. This suggests that we really are persuaded more strongly when we make the argument ourselves, even if it isn’t in line with our own viewpoint.

There’s a powerful signalling story to all this, of course. He who more convincingly passes the ITT can say he withstood the powers of self-persuasion. He is RIGHT.

And ideologues everywhere are scrambling to seize the ITT high ground. Caplan’s inspiration is Paul Krugman, who once said this:

[I]f you ask a liberal or a saltwater economist, “What would somebody on the other side of this divide say here? What would their version of it be?” A liberal can do that. A liberal can talk coherently about what the conservative view is because people like me actually do listen. We don’t think it’s right, but we pay enough attention to see what the other person is trying to get at. The reverse is not true.

Eric Barker disagrees:

Who was best able to pretend to be the other?

The results were clear and consistent. Moderates and conservatives were most accurate in their predictions, whether they were pretending to be liberals or conservatives. Liberals were the least accurate, especially those who described themselves as “very liberal.”

The bottom line? The stakes are too high for anyone to actually undergo a real ITT.

Freddie is a disembodied creature, an animal that is more important as data than as meat or muscle. Though he’s been mentioned in thousands of web pages and dozens of trade industry articles, no one mentions where he was born or where the animal currently lives. He is, for all intents and purposes except for his own, genetic material that comes in the handy form of semen. His thousands of daughters will never smell him and his physical location doesn’t matter to anyone.

What is Freddie? The greatest sire of diary cows the world has ever seen.

While there are more than 8 million Holstein dairy cows in the United States, there is exactly one bull that has been scientifically calculated to be the very best in the land. He goes by the name of Badger-Bluff Fanny Freddie….

In January of 2009, before he had a single daughter producing milk, the United States Department of Agriculture took a look at his lineage and more than 50,000 markers on his genome and declared him the best bull in the land. And, three years and 346 milk- and data-providing daughters later, it turns out that they were right.

More here. It’s a big data story of course and they’re lucky to have great data and narrow predictive objectives:

Data-driven predictions are responsible for a massive transformation of America’s dairy cows. While other industries are just catching on to this whole “big data” thing, the animal sciences — and dairy breeding in particular — have been using large amounts of data since long before VanRaden was calculating the outsized genetic impact of the most sought-after bulls with a pencil and paper in the 1980s.

Dairy breeding is perfect for quantitative analysis. Pedigree records have been assiduously kept; relatively easy artificial insemination has helped centralized genetic information in a small number of key bulls since the 1960s; there are a relatively small and easily measurable number of traits — milk production, fat in the milk, protein in the milk, longevity, udder quality — that breeders want to optimize; each cow works for three or four years, which means that farmers invest thousands of dollars into each animal, so it’s worth it to get the best semen money can buy. The economics push breeders to use the genetics.

And on Freddie’s eventual fate:

It might seem that Badger-Bluff Fanny Freddie is the pinnacle of the Holstein bull. He’s been the top bull since the day his genetic markers showed up in the USDA database and his real-world performance has backed up his genome’s claims. But he’s far from the best bull that science can imagine…

He will be replaced very soon by the next top bull, as subject to the pressures of our economic system as the last version of the iPhone.

Amazing article in the wsj (mercifully ungated) on a study about what happens when you talk about yourself:

Talking about ourselves—whether in a personal conversation or through social media sites like Facebook and Twitter—triggers the same sensation of pleasure in the brain as food or money, researchers reported Monday.

About 40% of everyday speech is devoted to telling others about what we feel or think. Now, through five brain imaging and behavioral experiments, Harvard University neuroscientists have uncovered the reason: It feels so rewarding, at the level of brain cells and synapses, that we can’t help sharing our thoughts.

“People were even willing to forgo money in order to talk about themselves,” Ms. Tamir said.

Isn’t that amazing? You can see why people say stupid things in interviews and the like: they’re so high on having someone listen to them that they mess up!

I’d love to see a study of people who read transcripts of themselves talking about themselves months later: I’d imagine they’d judge it harshly.