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Scientists Weigh Smallest Mass Ever
PaSTE writes "From the article, 'US scientists have managed to measure the mass of a cluster of xenon atoms at just a few billionths of a trillionth of a gram - or a few zeptograms. The record measurement is in the mass range of individual protein molecules, and the detection was made using sensitive scales developed at Caltech.' Another big leap forward for nanotechnology."
A related article from less than 24 hours ago covers another use of the nanomechanical scale developed at Caltech. This article is not exactly a dupe because it talks about a different application of the same scale.
The smallest mass ever measured would have to go to the electron. However, the measurement does not involve a scale but rather manipulation of electric fields. Moreover, scientists have shown that nuetrinos do in fact have mass (previously thought to be massless) and soon it will be the smallest mass ever measured
You don't have to be smart to use a Mac, you just have to be smart enough to buy one
The thing that pisses me off about it is that some fuckers in Washington and Florida (and probably elsewhere with less outgoing news coverage) got votes out of this woman.
You know, you can replace that with just about anybody famous or not, and chances are somebody will agree with you. That doesn't stop you from being incredibly not funny.
[disclaimer] I am rather liberal, and dislike GWB as much as any leftist man. But come ON people. Harding was MUCH dumber than GWB. You know, mister "You'll have to ask my advisor about that tax thing. There was a book about this tax thing which was supposed to explain it to be, but hell, i don't understand the book!"
A photon not "in transit" makes no sense. They have zero-rest mass, which doesn't say much, because they are never at rest. However, although they are massless, the do have momentum, determined by this equation.
p=h*f/c
h = is Plank's constant, f= frequency of the photon, and c = speed of light. Since h and c are constants, then the only thing the photon exchanges to transfer momentum is frequency. Weird.
That's right. All your base.
By looking at the change in resonance frequency, they are measuring the mass, not the weight. Therefore the results are the same on any planet, space station, etc. But can you call this procedure weighing?-)
Escher was the first MC and Giger invented the HR department.
Let's see, the smallest protein product I can find at the moment is NP_871795, a splice variant of C. elegans gene "thioredoxin H", encoding just seven amino acids: MTIYFTV, it weighs in at about 870 daltons (the full gene is 12.5 kD), which is just around the claimed "a few zeptograms" - 1.45 to be more precise.
Looks like for once the irrelevant biological reference is at least accurate. (for reference, the largest product is NP_787974 in drosophila: 2451.35 kilodaltons).
Maybe I'm not getting it, but I don't quite see the medical application of this. Many of the most common techniques in proteomics and molecular biology are based around measuring the weight of proteins (and other molecules), I don't know what benefits direct measurement would add. Unless it were cheaper or less labor intensive, which this doesn't sound like it is.
I'm guessing they just wanted to get the word "cancer" in there somewhere.
sic transit gloria mundi