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Comment Not that surprising (Score 2) 147

This isn't a big shock. In nature, there is a process called isotope fractionation. The idea is simple, in biological systems lighter isotopes react faster. Also with something like the evaporation of water, the heavy water will naturally be discriminated against. This means that in plants, carbon 13 and especially 14 do not react as quickly as carbon 12. The plants as a result contain less carbon 13 and 14 than you would otherwise expect. We usually measure this depletion against a worldwide limestone standard, when values carbon 13 can be up to 30% less for oils and fuels which have been processed by plants and microbes. We can actually use the depletion value to determine if an oil is 'ready' to be extracted and its quality or find what plant (or type of plant) a sample may have come from. While this is a very well documented and understood phenomenon, it has safely been ignored up until now. In test tubes the isotopes react more or less the same and most chemists don't give it a second thought. Any real work that needs very precise and accurate masses can utilize equipment like high res mass spec, which can tell you the amount of each isotope present. This paper proposes using an interval to cover this fractionation that can occur, making the point that you cannot assume the ratio of carbon 12 to carbon 13 (or any other element) is constant throughout the universe, which changes the average molecular mass.

Comment Re:Screening (Score 1) 202

Thats not correct. My university does a fair amount of isotope data, and there are no sensors. It requires GC-MS instruments (many thousands of dollars) teamed up with liquid nitrogen, combustion chambers, very large cylinders of gas and certified standards. There is no small amount of work in accumulating isotope data for complex (and not so complex) molecules. The data you get is very crude to say the least. Sure, you can tell if someone consumed (not all water is drunk) isotopically heavy or light substances, but that is about the sum of it. Isotopes are processed very differently by different systems in the body (as a rule, heavier isotopes react much slower in biological systems) which confuses the process to the nth degree (these processes are still debated in the simplest of lifeforms, let alone humans). As a scientist, while the technology is real (and has been for a couple of decades), their assertion that the numbers would be in any way meaningful is just fantasy. Put the tin foil hats away.

Comment A tad optimistic (Score 1) 84

Something about the mindless optimism of the scientists always makes me smile. They produce a sheet the size of a playing card that can slowly fold itself into a few predetermined shapes. While this is impressive, the technology is clearly miles away from tripods and auto-adjusting cups. This is a symptom of a research framework that only focuses on marketable products, and doesn't give a stuff about the actual progress being made.

Comment Australia Does it (Score 1) 613

Here is australia we get to do it all online. Every year the ATO (tax office) releases software that can be used to compile and submit your tax information. When it runs, it gives you the option to obtain all information it can, including income, health insurance, social security payments, education debts and more obscure things. This system means my tax return involves running this application, making sure the information is correct, enter in some non-invented deductions and hit submit. Takes ten minutes, and the return is processed in a few days. It seems very hard to believe that Australia can manage to make a system that the US considers no viable.

Comment I have to support Google at this point (Score 1) 473

Reason is that copyright terms are so damn stupidly long. Given that a work is not only copyrighted for the life of an author, but for years after that, it is a major problem. What happens if an author has died and you really aren't sure who owns the rights?

If copyright got dialed back to a reasonable term, then I'd say sure, let's not do this. Google can publish anything out of copyright, or anything given to them. However as it stands if you don't have some sort of opt out system it will mean that defacto almost nothing will be available on there.

Comment Checklists, etc. (Score 3, Interesting) 215

Probably a lot of books written on it -- Atul Gawande did a pretty big "study" with safety checklist prior to OR activation. We have several checklists (independent of anesthesia) before starting any invasive procedure, so this is kind of behind the times. It is more targeted at foreign hospitals or places that have a lot of mid-level providers that are not used to things. If you are interested, the full study can be found here:

http://content.nejm.org/cgi/content/full/NEJMsa0810119

gbutler69 writes:
>Says who? Citation Please?
[snip a bunch of rhetorical questions]

From your questions I infer you are completely out of touch with this field in any sort of form. If you want a citation, do a tad of research on your own and you will discover things; I won't spoon-feed.

Poke around here to start (but some of this might be biased the *other* way.) Do a good deal of academic reading and you will get a good feel of what is going on:

http://www.sickoflawsuits.org/

Comment Re:Wha...? (Score 1) 114

These gases were used because they are rare. To be of any value, the gas has to be inert, so it doesn't undergo a natural fractionation (all biological systems favour lighter isotopes). We also need a very old reliably dated source. These gases are used as an indicator for the atmosphere as a whole, and provide the best proxy. Isotope data can be difficult to interpret at the best of times, it's best to take these hypothesis with a grain of salt.

Comment This is more common than you think.... (Score 1) 656

At my university we had a small orientation before we were let lose supervising undergraduate students in labs. One of the topics discussed was the difficulty in teaching someone with preconceived ideas, and how many people have the wrong idea on very 'fundamental' issues. We did a simple test, get into groups of three or four, and produce a little presentation about why we have seasons and why the moon has different phases. This seems like a simple ask, also keep in mind that we are all either final year or postgraduate science (physics and chemistry) majors. Most groups got it wrong. Some fundamentally (the earth creates a shadow on the moon) but most had the basic ideas and failed in the reasoning (such as the tilted axis causing seasons, but fail to realise it is due to flux and related it instead to distance). It's easy to scoff at people who got this wrong, but this wasn't Joe public; this was a large group of scientists, each beginning to specialise in a very technical field. The teaching of basic scientific principals has been left for dead, and the current climate of students is that if something is not assessed, it is not important. Gone are the days that students would look for these answers on their own. Something to ponder, could you imagine the headlines if a reporter was in the room?

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