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Sadly, given Celera's past history, it will almost certainly be proprietary. Although they have benefited immensely from government funded research and data collection, they have refused to make their sequence data publicly available in GenBank. Most journals require you to publish your sequence data in GenBank as a condition for publication of papers related to the sequence data. Celera was granted a special exemption to this policy by Science when they published their paper on the human genome recently and I anticipate a similar special exemption will be allowed for the mouse data as well, though I haven't closely followed what's going on with the mouse genome, since I work on Acetabularia Acetabulum (this is my professor's web page, not mine, the views expressed here are not ...and so on)

If you want to analyze publicly available gene sequence data, you can use GenBank at NCBI and software from Bioinformatics.org. There is also a great directory of online molecular biology tools and information here

I'm constantly wanting access to papers published in, say, Science. If they charged a dollar or something for access, that'd be nominally acceptable, but they are selling someone else's work, and not paying them for it. It would also be marginally acceptable if they charged the subscription amount, and then gave any money not needed to run the site to the people who wrote the papers.

We should all boycott people like Science online who don't give up the text until a year after publication. They're holding our science hostage. On top of that, I couldn't even get in to the place where you register for basic (Free) access which gives you access to articles older than one year, supposedly. Oh, and in order to subscribe to the online version of Science, you also have to have a subscription to their print publication. Tell me again why scientists choose to support these money-grubbers?

I think that what this boils down to is that there needs to be some sort of nonprofit which exists only to make scientific papers available for as little money as possible. Maybe there already is, and it just needs more press; In which case, we should do what we can to ensure that it gets it.

--
ALL YOUR KARMA ARE BELONG TO US

I'm constantly wanting access to papers published in, say, Science. If they charged a dollar or something for access, that'd be nominally acceptable, but they are selling someone else's work, and not paying them for it. It would also be marginally acceptable if they charged the subscription amount, and then gave any money not needed to run the site to the people who wrote the papers.

We should all boycott people like Science online who don't give up the text until a year after publication. They're holding our science hostage. On top of that, I couldn't even get in to the place where you register for basic (Free) access which gives you access to articles older than one year, supposedly. Oh, and in order to subscribe to the online version of Science, you also have to have a subscription to their print publication. Tell me again why scientists choose to support these money-grubbers?

I think that what this boils down to is that there needs to be some sort of nonprofit which exists only to make scientific papers available for as little money as possible. Maybe there already is, and it just needs more press; In which case, we should do what we can to ensure that it gets it.

--
ALL YOUR KARMA ARE BELONG TO US

... arti cles are belong to us.

____________________________
2*b || !(2*b) is a tautology

... arti cles are belong to us.

____________________________
2*b || !(2*b) is a tautology

The article was published in today's issues of the journal Science, abstract. (A paid subscription is required to read the full article...)

The paper by Shelby et al. is here, but I belive full access requires a subscription. (Most universities have this.) Wiltshire has a less technical Perspective in the same issue.

Bob

The paper by Shelby et al. is here, but I belive full access requires a subscription. (Most universities have this.) Wiltshire has a less technical Perspective in the same issue.

Bob

While here is the full research article in science magazine.

Both of these require a subscription, but you can read the abstract without paying.

While here is the full research article in science magazine.

Both of these require a subscription, but you can read the abstract without paying.

--Ben

can be found at Science Magazine.

Some magazines do this. Science is a high-visibility example. Free access to digital articles for subscribers, and others can purchase on-line access.

This could allow the creation of self assembling superconducting circuits.

You do not know what you are talking about. Climate change due to human activities absolutely HAS been proven, for any reasonable standard of 'proof'.

Some random links. Yes I know these aren't authoratitive primary sources but you can't deep link into the `Nature' site :(
BBC News
BBC News
paper in `Science'
Crowley in `Science'
(UN) IPCC
more U.N.
NASA
NASA
NASA
Nature
BBC News
New Scientist's excellent overview, ideal for clueless know-nothing^W^W getting a basic grounding in the major issues

Next time, try to avoid talking nonsense on a subject you know nothing about.
--
If the good lord had meant me to live in Los Angeles

You do not know what you are talking about. Climate change due to human activities absolutely HAS been proven, for any reasonable standard of 'proof'.

Some random links. Yes I know these aren't authoratitive primary sources but you can't deep link into the `Nature' site :(
BBC News
BBC News
paper in `Science'
Crowley in `Science'
(UN) IPCC
more U.N.
NASA
NASA
NASA
Nature
BBC News
New Scientist's excellent overview, ideal for clueless know-nothing^W^W getting a basic grounding in the major issues

Next time, try to avoid talking nonsense on a subject you know nothing about.
--
If the good lord had meant me to live in Los Angeles

In any event (and this is not my specialty, so take this with the standard grain o' salt), the reason that a collapsar is expected to stop collapsing at neutron-star stage is that the neutron degeneracy pressure (basically, the Pauli Exclusion Principle in action) is able to resist the mutual gravitational forces up to some limit -- by calculation, 1.4 to 1.8 solar masses, although it appears that a value of 2.3 solar masses has been observed. Clearly, though, greater densities can exist, because if the limiting mass is exceeded the collapse continues -- to form a black hole, if you accept the present standard formulations of the problem. It's just that we don't know of a stronger force than neutron degeneracy, which will be able to resist the gravitational collapse. During the formation event (typically a supernova), if the collaspe forces (gravitation, implosion) exceed the neutron degeneracy forces, there's nothing to stop the continued collapse (through higher densities) to a black hole. Our lack of knowledge doesn't mean there's not a further stable state, though -- only that we don't know about it. Some scientists have speculated that a further point might exist in a quark star, which would consist (at least in its core) of free strange quarks. But some models of quark stars end up with lower densities than neutron stars... the problem is that we just don't know enough, yet.

(BTW, there's good info here on neutron stars, from a specialist.)

---

http://www.sciencemag.org/cgi/content/summary/290/ 5500/2236

The CNN article was basically on a subset of this interview. Also please remember that this doesn't mean that NASA will get more money, just that a president who is about to leave office thinks that they should get more money.

"Informative"? This guy was so quick to post for karma that he apparently didn't bother to read Science's policy. :-)

The information will be freely available if you don't want to commercialize it.

Of course, they do have that 1MB-limit problem...
--
Patrick Doyle

Is it possible to detect which aa's are present and in which proportions?

Glycine is the only one I remember, for sure... but I just did a search on Google for "interstellar molecular cloud amino acid spectra" and got about a hundred hits, the first several of which were annotated bibliographies on the subject of ET life origin. You might want to check the same?

Also, have nucleic acids been detected in these clouds?

I'm sure they haven't -- the spectra of complex organics is very complex itself, and there are arguments about the spectra of much simpler compounds (remember, there's a complex mix of molecular species, at very low temperatures, and plenty of stuff between us and them to filter and obfuscate the results). AFAIK, nucleic acids haven't been found in meteorites, either -- but plenty of amino acids have been; upwards of 50 the last time I checked. (Some reports of chirality selection, too -- and speculation that it might be from circularly-polarized light in the IMC.)

What do you say, tesserae....want to submit it?

This topic's gonna be dead soon -- email me and I'll be happy to discuss it more.

---

Is it possible to detect which aa's are present and in which proportions?

Glycine is the only one I remember, for sure... but I just did a search on Google for "interstellar molecular cloud amino acid spectra" and got about a hundred hits, the first several of which were annotated bibliographies on the subject of ET life origin. You might want to check the same?

Also, have nucleic acids been detected in these clouds?

I'm sure they haven't -- the spectra of complex organics is very complex itself, and there are arguments about the spectra of much simpler compounds (remember, there's a complex mix of molecular species, at very low temperatures, and plenty of stuff between us and them to filter and obfuscate the results). AFAIK, nucleic acids haven't been found in meteorites, either -- but plenty of amino acids have been; upwards of 50 the last time I checked. (Some reports of chirality selection, too -- and speculation that it might be from circularly-polarized light in the IMC.)

What do you say, tesserae....want to submit it?

This topic's gonna be dead soon -- email me and I'll be happy to discuss it more.

---

To examine whether bone marrow-derived cells could give rise to cells in the brain, adult marrow was harvested from transgenic mice (8 to 10 weeks of age) that ubiquitously expressed enhanced green fluorescent protein (GFP) (13). GFP-expressing (GFP+) bone marrow was administered by tail vein injection (6 × 106 nucleated cells per recipient) into lethally irradiated, isogenic adult (8- to 10-week-old) recipients (14). Brains harvested several months after the transplant (post-transplant) and examined by light microscopy revealed the presence of GFP+ cells throughout the CNS, including the olfactory bulb, hippocampus, cortical areas, and cerebellum. No cells expressed detectable GFP in five age-matched bone marrow recipients (controls) transplanted with marrow that was not genetically engineered to express GFP. Thus, bone marrow-derived GFP+ cells were clearly present in the brain.

To examine whether bone marrow-derived cells could give rise to cells in the brain, adult marrow was harvested from transgenic mice (8 to 10 weeks of age) that ubiquitously expressed enhanced green fluorescent protein (GFP) (13). GFP-expressing (GFP+) bone marrow was administered by tail vein injection (6 × 106 nucleated cells per recipient) into lethally irradiated, isogenic adult (8- to 10-week-old) recipients (14). Brains harvested several months after the transplant (post-transplant) and examined by light microscopy revealed the presence of GFP+ cells throughout the CNS, including the olfactory bulb, hippocampus, cortical areas, and cerebellum. No cells expressed detectable GFP in five age-matched bone marrow recipients (controls) transplanted with marrow that was not genetically engineered to express GFP. Thus, bone marrow-derived GFP+ cells were clearly present in the brain.

As far as stereo-selectivity goes, there's good evidence that small-scale structure is inherently chiral: look at carbon single-wall nanotubes, or gold nanotubes -- they naturally form stable spiral structures. Almost every nanostructure we make appears to do that. All you need is an imbalance at some point to evolve specificity for one stereoisomer -- and that imbalance can be as simple as the magnetic field from a nearby supernova remnant, biasing the chemistry in an IMC.

As for life surviving in space, common soil bacteria (Bacillus subtilis) survived unprotected in space aboard the Long Duration Exposure Facility (LDEF) for 6 years. That's bacteria, not spores! A recent paper in Science demonstrated that the interior of the martian meteorite recently alleged to contain fossil evidence of life wasn't subjected to temperatures above 40 C during the entire journey from Mars, including atmospheric entry at Earth. And those researchers noted that "every million years, ~10 rocks larger than 100 g are transferred in just 2 to 3 years" from Mars to Earth. It's an energetically-favorable trajectory.

I'm not suggesting so much that terrestrial life contaminated Mars -- it's much more likely that we're originally martians. A common chemistry won't surprise me at all.

---

In reply to your question: my favorite pet speculation is that essentially all of the prebiotic evolution and the fundamentals of the biotic evolution of life (including what you might call the "formal" origin-of-life) occurred somewhere other than on a planet.

There's plenty of evidence that amino acids are created in interstellar molecular clouds (IMCs -- we routinely detect them there with spectrographs, and more complex molecules are being found all the time); the basic reason is that the IMCs are rich in the chemical species necessary, are cold enough and well-enough shielded from UV that the fragile compounds are stable for long enough for the chemistry to develop (and this is accretional chemistry, BTW -- and it takes a long time!), and full of interstellar dust and icy grains which provide excellent surfaces for the chemistry to proceed upon. And after all the prebiotic stuff happens, over billions of years in IMCs, the IMCs condense into new stellar systems, complete with plenty of warmer protoplanetary bodies -- like comets and asteroids -- within which there are great opportunities and lots of substrates for life to develop on, without all of the nasty disadvantages to planetary surfaces. These substrates, BTW, include clay minerals -- the Tagish Lake meteorite is a great example of that -- and plenty of organics, including amino acids in quantity. And the temperatures are still low enough that the fragile molecules survive for long periods.

Then the planetary bodies (including appropriate satellites) get seeded by the life-bearing bodies -- which have recently been shown to be gentle enough to avoid killing any life aboard -- and the life promptly takes over the new environment. After the planets have calmed down, the life actually survives, to eventually become us...

Not quite original (props to Fred Hoyle, among others), but the general scheme answers many of the tough questions about life's origin on planetary bodies.

And I think this would be a great topic for a /. story -- just to get more comments. Any ideas there, yardgnome?

---

In reply to your question: my favorite pet speculation is that essentially all of the prebiotic evolution and the fundamentals of the biotic evolution of life (including what you might call the "formal" origin-of-life) occurred somewhere other than on a planet.

There's plenty of evidence that amino acids are created in interstellar molecular clouds (IMCs -- we routinely detect them there with spectrographs, and more complex molecules are being found all the time); the basic reason is that the IMCs are rich in the chemical species necessary, are cold enough and well-enough shielded from UV that the fragile compounds are stable for long enough for the chemistry to develop (and this is accretional chemistry, BTW -- and it takes a long time!), and full of interstellar dust and icy grains which provide excellent surfaces for the chemistry to proceed upon. And after all the prebiotic stuff happens, over billions of years in IMCs, the IMCs condense into new stellar systems, complete with plenty of warmer protoplanetary bodies -- like comets and asteroids -- within which there are great opportunities and lots of substrates for life to develop on, without all of the nasty disadvantages to planetary surfaces. These substrates, BTW, include clay minerals -- the Tagish Lake meteorite is a great example of that -- and plenty of organics, including amino acids in quantity. And the temperatures are still low enough that the fragile molecules survive for long periods.

Then the planetary bodies (including appropriate satellites) get seeded by the life-bearing bodies -- which have recently been shown to be gentle enough to avoid killing any life aboard -- and the life promptly takes over the new environment. After the planets have calmed down, the life actually survives, to eventually become us...

Not quite original (props to Fred Hoyle, among others), but the general scheme answers many of the tough questions about life's origin on planetary bodies.

And I think this would be a great topic for a /. story -- just to get more comments. Any ideas there, yardgnome?

---

In reply to your question: my favorite pet speculation is that essentially all of the prebiotic evolution and the fundamentals of the biotic evolution of life (including what you might call the "formal" origin-of-life) occurred somewhere other than on a planet.

There's plenty of evidence that amino acids are created in interstellar molecular clouds (IMCs -- we routinely detect them there with spectrographs, and more complex molecules are being found all the time); the basic reason is that the IMCs are rich in the chemical species necessary, are cold enough and well-enough shielded from UV that the fragile compounds are stable for long enough for the chemistry to develop (and this is accretional chemistry, BTW -- and it takes a long time!), and full of interstellar dust and icy grains which provide excellent surfaces for the chemistry to proceed upon. And after all the prebiotic stuff happens, over billions of years in IMCs, the IMCs condense into new stellar systems, complete with plenty of warmer protoplanetary bodies -- like comets and asteroids -- within which there are great opportunities and lots of substrates for life to develop on, without all of the nasty disadvantages to planetary surfaces. These substrates, BTW, include clay minerals -- the Tagish Lake meteorite is a great example of that -- and plenty of organics, including amino acids in quantity. And the temperatures are still low enough that the fragile molecules survive for long periods.

Then the planetary bodies (including appropriate satellites) get seeded by the life-bearing bodies -- which have recently been shown to be gentle enough to avoid killing any life aboard -- and the life promptly takes over the new environment. After the planets have calmed down, the life actually survives, to eventually become us...

Not quite original (props to Fred Hoyle, among others), but the general scheme answers many of the tough questions about life's origin on planetary bodies.

And I think this would be a great topic for a /. story -- just to get more comments. Any ideas there, yardgnome?

---

Gil Levin isn't the only one who is persistent, however, because a few months back a NASA-associated group published a paper in Science dealing with this very topic. Quoting from the abstract:

Using electron paramagnetic resonance spectroscopy, we show that superoxide radical ions (O2-) form directly on Mars-analog mineral surfaces exposed to ultraviolet radiation under a simulated martian atmosphere. These oxygen radicals can explain the reactive nature of the soil and the apparent absence of organic material at the martian surface.

It took them almost 25 years to get this far; does this answer those people who claim that Levin is a flake because he won't let go of his ideas?

Personally, I think the surface of Mars isn't the place to look for life; I think we need to look subsurface, because of things just like this latest paper. Which, by the way, really doesn't invalidate Levin's tests, because the soil samples included both surface and subsurface material -- added complexity, isn't it?

---

I'll make it up to you: the same other account lets me past the screening to the WAV files -- the song the humpbacks sang last year, and the one they picked up from those westcoast punks this year.

And as a bonus, here's the complete story (a short one) from ScienceNOW:

Whales' Cultural Revolution

Just as the Beatles once revolutionized American music, a small band of whales seems to have introduced a new musical style to whales living off Australia's East coast. In little more than a year, the crooning visitors managed to make their tune the major local hit, according to a study in the 20 November issue of Nature.

In humpback whales, the vocalists are always male, and they apparently sing to impress females. Each population has its own "in" song, which gradually evolves. That happens when one crooner embellishes his tune with an extra trill or groan, and others in the area pick up the riff. Females probably get bored by the same old song, says bioacoustician Michael Noad from the University of Sydney in Australia, so males keep adding new fillips to spice things up. But switching to a completely different song is unheard of, Noad says; deviating so far from the norm might label the singer as weird, rather than irresistibly trendy, he speculates.

So Noad and his colleagues, who have studied whale songs for many years, were surprised when their hydrophones picked up a novel song in 1996, one that became dominant by late 1997 and the only thing on the charts in 1998. (Click here for the old and the new song.) "The main part of the change just happened over a couple of months," he says. "It was extraordinarily rapid." Initially, the team had no idea where the song had come from--until Noad listened to a tape of western Australia humpbacks. "It was an exact match, no doubt about it."

The team figures the western Australian whales must have introduced the song when they accidentally headed to the east during their annual migration from Antarctica. But he has no idea why their song became popular so fast.

"This is very surprising," says whale researcher and bioacoustician Adam Frankel of Marine Acoustics Inc. in Arlington, Virginia. Nobody had ever reported such a cultural revolution among whales before, Frankel says. "It's huge."

--MARI N. JENSEN

---

I'll make it up to you: the same other account lets me past the screening to the WAV files -- the song the humpbacks sang last year, and the one they picked up from those westcoast punks this year.

And as a bonus, here's the complete story (a short one) from ScienceNOW:

Whales' Cultural Revolution

Just as the Beatles once revolutionized American music, a small band of whales seems to have introduced a new musical style to whales living off Australia's East coast. In little more than a year, the crooning visitors managed to make their tune the major local hit, according to a study in the 20 November issue of Nature.

In humpback whales, the vocalists are always male, and they apparently sing to impress females. Each population has its own "in" song, which gradually evolves. That happens when one crooner embellishes his tune with an extra trill or groan, and others in the area pick up the riff. Females probably get bored by the same old song, says bioacoustician Michael Noad from the University of Sydney in Australia, so males keep adding new fillips to spice things up. But switching to a completely different song is unheard of, Noad says; deviating so far from the norm might label the singer as weird, rather than irresistibly trendy, he speculates.

So Noad and his colleagues, who have studied whale songs for many years, were surprised when their hydrophones picked up a novel song in 1996, one that became dominant by late 1997 and the only thing on the charts in 1998. (Click here for the old and the new song.) "The main part of the change just happened over a couple of months," he says. "It was extraordinarily rapid." Initially, the team had no idea where the song had come from--until Noad listened to a tape of western Australia humpbacks. "It was an exact match, no doubt about it."

The team figures the western Australian whales must have introduced the song when they accidentally headed to the east during their annual migration from Antarctica. But he has no idea why their song became popular so fast.

"This is very surprising," says whale researcher and bioacoustician Adam Frankel of Marine Acoustics Inc. in Arlington, Virginia. Nobody had ever reported such a cultural revolution among whales before, Frankel says. "It's huge."

--MARI N. JENSEN

---

Plus links to more cetacean and other sea mammal sites, too.

---

I suspect life was ready for the transition before the environment was. I have this funny vision of the ocean stuff keeping an eye on the land, saying "Okay, now, it's getting ripe -- get ready to go for it!"

As an interesting aside, last week's Science had a great paper (summary here) about new discoveries possibly related to early life: an RNA-analogue which uses much simpler tetrose backbone sugars, and is still able to not only form stable Watson-Crick helices with itself, but also with complementary RNA and DNA! The RNA backbone monomers (beta-nucleotides) are difficult to form under primordial conditions, while the tetrose sugars are almost trivially easy to form under prebiotic reducing conditions. This is the first of what's anticipated to be a whole family of plausible RNA precursors -- and that's a huge first!

Not to start a flame war, but it's a major chunk of hard scientific evidence (as opposed to speculation and theorizing) supporting a gradualist development of biotic chemistry -- and a very significant blow to those who argue for creationism based on the complexity of RNA and DNA chemistry. The gaps keep getting smaller...

---

I suspect life was ready for the transition before the environment was. I have this funny vision of the ocean stuff keeping an eye on the land, saying "Okay, now, it's getting ripe -- get ready to go for it!"

As an interesting aside, last week's Science had a great paper (summary here) about new discoveries possibly related to early life: an RNA-analogue which uses much simpler tetrose backbone sugars, and is still able to not only form stable Watson-Crick helices with itself, but also with complementary RNA and DNA! The RNA backbone monomers (beta-nucleotides) are difficult to form under primordial conditions, while the tetrose sugars are almost trivially easy to form under prebiotic reducing conditions. This is the first of what's anticipated to be a whole family of plausible RNA precursors -- and that's a huge first!

Not to start a flame war, but it's a major chunk of hard scientific evidence (as opposed to speculation and theorizing) supporting a gradualist development of biotic chemistry -- and a very significant blow to those who argue for creationism based on the complexity of RNA and DNA chemistry. The gaps keep getting smaller...

---

The ATP-fueled motors, of course, are just F1-ATPase enzyme, straight from bacteria... and the enzyme is indeed nanoscale, at ~8 nm diameter and 14 nm length. But Montemagno didn't build it, just co-opted it.

(The article linked will probably require a paid subscription... sorry 'bout that)

---

The authors conclude that "these data support the hypothesis that meteorites could transfer life between planets in the solar system." Not just the chemical precursors for life, as Jenniskens et al. are reporting -- they state that "[e]very million years, ~10 rocks larger than 100 g are transferred in just 2 to 3 years", and point out that microorganisms and bacterial spores can survive 5 years in space, as shown by experiments on NASA's Long Duration Exposure Facility (LDEF).

Looks like panspermia's going to make a comeback... the authors of the Science paper even suggest there's no reason to quarantine the rocks from a Mars sample return mission, because whatever's there, we've already got.

---

The authors conclude that "these data support the hypothesis that meteorites could transfer life between planets in the solar system." Not just the chemical precursors for life, as Jenniskens et al. are reporting -- they state that "[e]very million years, ~10 rocks larger than 100 g are transferred in just 2 to 3 years", and point out that microorganisms and bacterial spores can survive 5 years in space, as shown by experiments on NASA's Long Duration Exposure Facility (LDEF).

Looks like panspermia's going to make a comeback... the authors of the Science paper even suggest there's no reason to quarantine the rocks from a Mars sample return mission, because whatever's there, we've already got.

---

The paper which has this experiment was just published in Science. You probably need to be connecting from somewhere that has subscribed to Science.

A good intro reference to DFSs is here.

dabacon

These SLEDs (Sound and Light Emitting Diodes) work in much the same way as a normal LED - spontaneous emission of photons from a forward biased p-n junction. But in the SLED, some of the photons of light are redirected through a resonant liquid crystal cavity, which causes vibrations of the resonant cavity at harmonics of the photon frequency. By changing the voltage applied to the liquid crystal cavity, different resonant points can be found and thus the frequency of the sound can be altered.

The researchers believe that this technology can be used to produce laptop screens which produce sounds from the screen itself, without the need for unwieldy speakers. They are also working on using lower frequencies, so that touching an image on the LED screen will produce a tactile sensation, as if you were touching the object in the image itself.

There's more stuff about SLED technology at the website of the journal Science.

A copy of the article can also be found here. (Maybe.)

I doubt that many (if any) genuine researchers really thought that there was any chance that the formations found on those meteorites were formed by life. I don't believe the meteorites themselves were faked but I have major doubts about the credibility of the researchers.

Believe what you will. The truth is that the researchers involved are all credible, with decent publishing histories behind them. And the initial paper was published in Science -- not exactly a journal known for accepting hoaxes, although they do like to be the first to publish controversial papers (and this was no doubt a controversial paper). But "controversial" != "hoax"... and the stature of some of the researchers involved is such that they'd be fools to perpetrate a hoax and destroy their careers.

I won't deny that NASA took advantage of the paper, but calling it a hoax is dangerously close to libeling some good researchers (only some of whom work for NASA). You might want to reconsider your statement?

---

Here's a direct link to the article. The problem with the link above is an extraneous period.

"organic" chemicals are not chemicals made by mother nature & sold in your health food store. they're not bacteria or any other biological system, including proteins. organic chemicals are exactly what the topic said : carbon based molecules. anything made of solely carbon, nitrogen, oxygen & hydrogen is generally considered organic. this would be as opposed to inorganic chemicals which contain metals, non-metals (like silicon) or either of the lanthanides or actinides.

when this article refers to organic chemicals it means stuff made in a lab by chemists & includes, as was mentioned previously, polymers, plastics etc.

the reason these systems are so interesting is their versatility. bell labs, uh sorry, lucent scientists recently showed some really neat behaviour in the anthracene/tetracene family (as in mothballs) including lasing (albeit at low temperatures, but you've got to cool most lasers anyways) & superconductivity. they've managed to build field-effect transistors out of single crystals of pentacene. all very cool stuff & some of it came out recently in either PRL or nature, ok now i can tell you it's science. if you do an authour search for batlogg you'll get a chronological list of what they've been up to. i will attempt to link the search results here (fingers crossed). you should be able to read the abstracts at least.

hope this clears up why organic chemicals have nothing to do with the organic world & why the NY times is so excited about organics.

chris

"organic" chemicals are not chemicals made by mother nature & sold in your health food store. they're not bacteria or any other biological system, including proteins. organic chemicals are exactly what the topic said : carbon based molecules. anything made of solely carbon, nitrogen, oxygen & hydrogen is generally considered organic. this would be as opposed to inorganic chemicals which contain metals, non-metals (like silicon) or either of the lanthanides or actinides.

when this article refers to organic chemicals it means stuff made in a lab by chemists & includes, as was mentioned previously, polymers, plastics etc.

the reason these systems are so interesting is their versatility. bell labs, uh sorry, lucent scientists recently showed some really neat behaviour in the anthracene/tetracene family (as in mothballs) including lasing (albeit at low temperatures, but you've got to cool most lasers anyways) & superconductivity. they've managed to build field-effect transistors out of single crystals of pentacene. all very cool stuff & some of it came out recently in either PRL or nature, ok now i can tell you it's science. if you do an authour search for batlogg you'll get a chronological list of what they've been up to. i will attempt to link the search results here (fingers crossed). you should be able to read the abstracts at least.

hope this clears up why organic chemicals have nothing to do with the organic world & why the NY times is so excited about organics.

chris

Lars
__

A recent article in Science discusses the fragility of even five-sigma results: rather than being wrong only once in a hundred times, three-sigma results are historically wrong about half the time, and five-sigma results are wrong much oftener than they "should" statistically be. As the article points out, the errors are often systematic: the experiment is designed to find a particular result, and if it doesn't give evidence quickly, it is often modified slightly and re-run; this can introduce large biases in the statistics.

So in the end, CERN isn't going to have "proof" of the Higgs discovery; basically, they're trying hard to get their names on the same page as those of the eventual credited discoverers, as precursors... not necessarily a bad thing, but also not worth the large penalties CERN will pay if they delay the start of LEP's replacement (the Large Hadron Collider) beyond another month.

---

However, that isn't the case here. First, this isn't just a collection of random gas giants. What was actually found was a loosely bound cluster of young dim stars, brown dwarfs, and gas giant planets. Based upon the surveyed area and the estimated size of the cluster, we're actually talking about several hundred objects. In fact, the reason they were looking there at all was because of spectroscopic anomalies in the vicinity of a visible star (the brightest star in the cluster).

Check out this article in Science magazine for full details.

Cepheid variables are stars that have very predictable relationships between their absolute brightness and the frequency with which they brighten up. A Cepheid is useful for measuring distances because, if it is known how bright the star really is, then it is a simple task to measure how bright it appears on Earth and then calculate the distance.

While this is mostly true, there's not simply a "very predictable relationship" between luminosity and distance -- as demonstrated by new information on Polaris (the North Star, a Ceppheid variable). In particular, check this graphic, which shows two distinct period-luminosity relationships (differing in the zero-point offset), depending on whether the Cepheid is a fundamental-mode or first overtone pulsator (and note that there's arguably some evidence of other pulsation modes in the clustering of points off the main trends, in the lower right-hand corner of the plot).

Just knowing the brightness of the Cepheid variable won't tell you how far away it is; you also have to know the pulsation mode, which isn't always easy. But then, astronomy hasn't ever been really easy... :) This data on Polaris comes from ground-based interferometry, by the way -- just a different instrument than that mentioned in the article -- as well as measurements from the Hipparcos satellite.

[I hope everyone can get to those URLs without having to pay -- I can't check that from here, 'cause I'm already logged into Science Online by default. Some info's available to everyone, some requires a subscription.]

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Cepheid variables are stars that have very predictable relationships between their absolute brightness and the frequency with which they brighten up. A Cepheid is useful for measuring distances because, if it is known how bright the star really is, then it is a simple task to measure how bright it appears on Earth and then calculate the distance.

While this is mostly true, there's not simply a "very predictable relationship" between luminosity and distance -- as demonstrated by new information on Polaris (the North Star, a Ceppheid variable). In particular, check this graphic, which shows two distinct period-luminosity relationships (differing in the zero-point offset), depending on whether the Cepheid is a fundamental-mode or first overtone pulsator (and note that there's arguably some evidence of other pulsation modes in the clustering of points off the main trends, in the lower right-hand corner of the plot).

Just knowing the brightness of the Cepheid variable won't tell you how far away it is; you also have to know the pulsation mode, which isn't always easy. But then, astronomy hasn't ever been really easy... :) This data on Polaris comes from ground-based interferometry, by the way -- just a different instrument than that mentioned in the article -- as well as measurements from the Hipparcos satellite.

[I hope everyone can get to those URLs without having to pay -- I can't check that from here, 'cause I'm already logged into Science Online by default. Some info's available to everyone, some requires a subscription.]

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The Hong and Mirkin reference is:
S. Hong and C. A. Mirkin, "A Nanoplotter with Both Parallel and Serial Writing Capabilities", Science 288(5472):1808-11 (9 Jun 2000).