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Comment Re:1% is probably true for all opiates (Score 4, Insightful) 499

I tried heroin once. Back in my hitch-hiking days I smoked it (believe it or not) with one of the drivers. It was absolutely wonderful. It felt like I just totally aced a toughest college exam. A complete euphoria. Pure happiness. In fact, it was so wonderful that I decided not try it ever again, because I could see how easily one can become addicted to it. But I did not get addicted. Then again, even back then, I was a motivated student, and my goal was to pursue science. Wasting my life doing drugs wasn't my plan. I might possibly try it again, given a chance, since it's now been almost 20 years. I am not planning on seeking it out, though, and I don't hitch-hike anymore, so I don't think it's going to happen, which is probably for the better.

Comment That doesn't make sense (Score 1) 379

That doesn't make sense. Once the beam has diverged enough to 'light up the entire plane', or even just the cockpit, the light intensity is very small. A powerful laser pointer has an output of ~250 mW (milliwatts). 250 mW dispersed over 1mm^2 is very strong illumination. 250 mW over the whole cockpit is nothing - same as a 250 mW lightbulb. Unless the cockpit is pitch dark, you will not even notice it.

Comment Regular salt - it contains potassium-40 (Score 5, Informative) 277

Use common kitchen salt (NaCl). It contains a small amount of potassium chloride (KCl). The amount of KCl in the salt you buy should be listed on the packaging. 0.012% of the KCl present will contain a naturally occurring radioactive isotope of potassium, potassium-40 (half-life of 1.3 billion years). So, if you weigh the amount of salt you test with your Geiger counter, you should be able to figure out how much potassium-40 you have. The specific activity of potassium-40 is 0.0000071 Curie/gram. One Curie is 3.7×10^10 decays per second, so one gram of potassium-40 should give you 263000 decays per second, one milligram of potassium-40 should give you 263 decays/second, and so on. By comparing your measurement results to what you would expect, you can tell how well your Geiger counter is performing. Be ready to measure for at least several minutes, though.

Comment Re:Bug antennae (Score 1) 190

Well, that paper came out in 1975, before the era of molecular biology, back when people knew almost nothing about how the sense of smell, or pheromone detection worked. In 1991 Buck and Axel published their paper in Cell on discovery of odorant receptor proteins (in mouse), which then led to discovery of odorant receptor proteins in insects, and other receptor protein families (V1R, V2R, TAAR) that are likely responsible for pheromone detection in mammals, and yet more receptor proteins likely responsible for pheromone detection in insects. Buck and Axel received a Nobel prize for their discovery. Btw., a 'vibrational theory of olfaction', similar to what you cite, popularized by the book The Emperor of Scent (Random House, 2002) was thoroughly destroyed by Leslie Vosshall's research published in 2004 in Nature Neuroscience.

Comment Re:Time machine not so great (Score 1) 266

1) Time machine backups can only be accessed from a Mac. Of course, I only realized this when I had my laptop in for a repair, when it turned out that although my files were safely backed up, they were completely inaccessible from my PC desktop.

Actually, the backup images are fairly 'standard' .sparseimage files. There are utilities available to read these disk images on Windows (and probably Linux as well).

Not anymore... The newer versions of TM don't use sparseimages but sparsebundles. No way to get the files out.

Otherwise, I agree with you.

Comment Time machine not so great (Score 0) 266

I also thought Time Machine was great when I got my first mac laptop last year, but since then I have found at least three things that really bug me.

1) Time machine backups can only be accessed from a Mac. Of course, I only realized this when I had my laptop in for a repair, when it turned out that although my files were safely backed up, they were completely inaccessible from my PC desktop.

2) Time machine keeps making incremental backups until it completely fills up the destination drive. Only then will it start rewriting the old incremental backups. There are reports on various websites that you can limit the size of the backup volume, but I haven't been able to get it to work. In the end I had to delete my backups, set up a new, clean partition on my external hard disk, and let Time machine use that.

3) Time machine doesn't work too well for backing up your local email mailbox. Pretty much every time your local inbox receives a new email, Time machine realizes that the mbox file has changed and runs a backup. Having a 2 GB mbox file backed up ten times a day is a drag - it clogs up the wifi connection and keeps the HD spinning.

Now I have Time machine back up only my OS X system/applications, and only after I install someting. I have other software back up my personal files. That way my files are backed up in PC readable format, and I have more control over how and when it's done. Time machine is slick, but has issues, ties you to the Mac platform, and it doesn't give you enough control.

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