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Comment I was the main research assistant for this study (Score 2) 294

I realize this isn't reddit, but, AMA.
I wasn't involved much in the study design in terms of the sampling methods themselves, but I did the site selection for the portion of our study that ended up published. It's been a few years but I still know it like the back of my hand.
I did all of the sampling itself and a large portion of processing the samples including the GC-MS portion. I was not involved much in the analysis except as a sounding board.

To address some of the concerns brought up thus far:
1) There are no known natural sources of caffeine in Oregon. There exists some coral in the indian ocean that secretes caffeine but nothing here locally, off-shore or terrestrial. Caffeine is not the best example, but, the idea is that it is a marker of human impact. We focused on waste water here because it's the most likely source.

2) Yes, you can accurately measure levels of ng/L. Yes, it's a pain. We actually did about a year of sampling, modifying our procedures, and tests before we were able to confidently prevent and rule out source of contamination. This even included not consuming caffeine in proximity to samples or before doing work with them.

3) I've not yet read the final paper (no uni access any more) but the other portion of the study we did was dosing pacific mussels with caffeine in a controlled environment. We looked at stress proteins, which are formed in response to environmental stressors, most notably heat. We did not observe an effect at the levels we measured in nature.

4) Excretion rate from humans is about 5%. Depending on the wastewater treatment regimen, primarily based on tertiary treatment like carbon filtering (very rare) and residence time, anywhere from 0% to 100% of caffeine can be removed. Further study here is necessary.

5) The half-life of caffeine in the environment is primarily heat related. Based on other studies we referenced, it's much longer in seawater. Off the top of my head the magnitude was on the order of 200 days in seawater vs 60-90 in fresh water. You should read the paper/references for exact numbers. This is far longer than the transit time from excretion to the ocean for most wastewater treatment. It does not bio-accumulate.

Cloud

Why Corporate Cloud Storage Doesn't Add Up 141

snydeq writes "Deep End's Paul Venezia sees few business IT situations that could make good use of full cloud storage services, outside of startups. 'As IT continues in a zigzag path of figuring out what to do with this "cloud" stuff, it seems that some companies are getting ahead of themselves. In particular, the concept of outsourcing storage to a cloud provider puzzles me. I can see some benefits in other cloud services (though I still find the trust aspect difficult to reconcile), but full-on cloud storage offerings don't make sense outside of some rare circumstances.'"

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