Friday, 9 September 2011

08:42 – Well, the copy finally finished at 10:00 p.m. last night, after 13 hours of writing 300,000+ files totaling about 1,300 GB. I’ll probably do the same thing again to a second new 2 TB Barracuda drive and then pull both of the old 1.5 TB drives. Of course, that leaves me with a system drive that’s older than either of those drives. Barracuda drives are extremely reliable, but these guys are well past retirement age in dog years.


Jerry Coyne just posted an interesting article about science versus religion, Adam and Eve: theologians squirm and sputter. The whole of Christianity is based on the Adam and Eve myth and original sin. Without that, Christianity has no basis whatsoever. And yet science tells us, indisputably, that Adam and Eve never existed. It is amusing to watch accommodationists try to reconcile religious myth with the cold, hard light of science.


We’ll be using a lot of dropper bottles for the biology kits, so I ordered a couple hundred dozen from one of my wholesalers in 15 mL and 30 mL capacities. These bottles are Chinese-made, and they’re fine except for one thing. They arrive with the dropper tips and caps installed, which means that Barbara and I have to disassemble them all before filling and labeling them, and then turn around and reinstall the dropper tips and caps. Doing that for a few bottles is no big deal. Doing it for thousands involves some work.

We’ll also need 30 mL wide-mouth bottles, which none of my current wholesalers offer. So I contacted a bottle supplier about the wide-mouth bottles and decided as long as I was at it to see what they had to offer in the way of dropper bottles. Their bottles are US-made, which is good, and they come in bulk with the dropper tips and caps in separate plastic bags. The problem is, bottles, even Chinese bottles, aren’t cheap, and the US-made ones cost 30% to 40% more than the Chinese-made ones. Still, I was willing to consider paying more for the US-made bottles. Until the samples arrived.

The problem is the dropper tips. The Chinese bottles have dropper tips whose bodies are long plugs that friction-fit the mouth of the bottle. Seating a dropper tip is a simple matter of pressing the tip into the mouth of the bottle until it seats. The dropper tips on the US bottles have much shorter bodies, and snap into place. The problem is that it requires close attention to make sure the tip has actually seated and snapped into place. This would slow down processing significantly, so I decided to stick with the Chinese bottles.

Speaking of processing bottles, I looked into automated methods and concluded that our current manual method is actually better unless and until we reach the point where we need to produce hundreds of kits per month. Working together, Barbara and I can fill, insert dropper tips, cap, and label the bottles at a rate of about 150 bottles per hour. (I fill and insert the dropper tips; Barbara caps and labels.) The only part of that that can be automated at anything approaching a reasonable price is the filling operation, but that still requires individual attention to each bottle as it’s filled, and actually saves almost no time.


10:36 – Barbara saw an article in the paper this morning about using copper sulfate to kill the mildew that’s appeared on some of her shrubs. I buy copper(II) sulfate by the kilogram, so she asked if I could make her up some right here in the sink. Of course, I agreed. The problem is, what concentration?

Apparently, the concentration needed varies. One site mentioned ranges from 2 to 6 pounds per 100 gallons, which translates to something like 909 to 2727 grams per 379 liters, or about 2.4 to 7.2 grams per liter. Or, as I think of it, about 0.01 to 0.03 molar. Since I keep liters of 1.0 M copper(II) sulfate solution in inventory–the stuff takes forever to dissolve–I’ll just compromise on 0.02 M and dilute one part of the stock solution to 49 parts water.

I did wonder whether the high solubility of copper(II) sulfate would be a problem. If Barbara sprays on 0.02 M copper(II) sulfate, it’ll stick around only until the next good rain dissolves it and rinses it off the plants. That’s apparently why people use Bordeaux or Burgundy mixtures, which are solutions of copper(II) sulfate mixed with either calcium hydroxide (lime) or sodium carbonate (washing soda or soda ash) to form insoluble precipitates of either copper hydroxide or copper carbonate. Apparently these are more persistent because they don’t dissolve in rainwater, but I do wonder whether they’d clog up Barbara’s sprayer. What the insoluble copper salts really are is time-release treatments, because even “insoluble” compounds are very slightly soluble in water. So, apparently copper(II) ions kill fungi even in nanomolar or even picomolar concentrations. I think we’ll start with just 0.02 M copper(II) sulfate solution and see if that makes the fungi gag, clutch their tiny little chests, and drop off the plants.


22 thoughts on “Friday, 9 September 2011”

  1. after 13 hours of writing 300,000+ files totaling about 1,300 GB

    I use an external SATA drive holder that allows me to just slip the drive in without any assembly. When I am done I just pull the drive out. The speeds are significantly faster than USB speeds. It was well worth the $24.00 (on sale when I bought it).

    http://www.newegg.com/Product/Product.aspx?Item=N82E16817153071

    Works well and I have no issues. I did have to install a card for external SATA that added a small amount to the cost. Don’t know if the card would work with Linux. My case also has an external SATA slot but it is on the front and I wanted one in the back.

  2. Yep, I have a similar eSATA docking station that holds two drives. There’s no issue with Linux. Throughput with the 2 TB Barracudas is up near 100 MB/s, versus 25 MB/s for the USB 2.0 frames. I just haven’t gotten around to digging it out of storage yet.

  3. Such huge file copies over USB are always a bit dangerous, often stopping in the middle due to mystery hiccups. What file copy tool did you use? Probably rsync?

  4. I think those problems are Windows-related. I’ve never had a problem doing huge copies with Linux, except once or twice when there was an actual hardware error. Yesterday, I just opened one directory window each for source and destination, did a shift-click to highlight all the files and directories on the source drive, and did a right-click-paste on the destination drive.

  5. For what it’s worth, I have started huge USB copies as well. I finally gave up using DVD’s for backups – it’s just too tedious, and the burning problems are a nuisance. I found a sale on “WD Elements” external USB drives, so I bought 4. Reformatted to an Ext4 filesystem, and copied the entire incremental backup (storebackup) drive over using “rsync -aH”. Let it run overnight, and voila!

    I didn’t mean to duck out of the home-schooling debate earlier, but I got buried this week, and am just now coming up for air. I think the only comments I still wanted to make are

    (a) It does take expertise to teach kids at the high-school level. If you are only a chapter ahead, you are going to lack the depth of knowledge necessary to answer the difficult questions, for example, *why* and *how* things work. This is especially true in fields like math and science, where you really want the students to think critically and ask those difficult questions.

    (b) Even earlier, it’s important that teachers genuinely like their subjects. If a parent dislikes math, or science, or history the kids are going to pick that up, and it is going to make a difference. The first time I thought history was anything more than memorizing stupid information was my first course by a genuine historian. He would get so caught up in teaching history that you couldn’t help yourself – it became fascinating.

    Both of these argue for people holding degrees (or equivalent) in the subjects they teach, in my mind, from the junior high level onwards. That’s hard to achieve (not impossible, just hard) with home-schooling groups.

  6. Both of these argue for people holding degrees (or equivalent) in the subjects they teach, in my mind, from the junior high level onwards. That’s hard to achieve (not impossible, just hard) with home-schooling groups.

    Oh, I agree. At the high school level, if not middle school, it would be nice to have each teacher hold a BS or better in the field he or she is teaching, at least for difficult subjects (i.e., math and science). The problem is, that’s much more likely to be true in a homeschool group with parents taking on particular subjects than it is in a public school. Very few public school math or science teachers (indeed very few public school teachers, period) hold BS degrees in anything meaningful. Most have a bachelor’s from the education department. In my opinion, and that of many others, that qualifies them to teach nothing whatsoever.

  7. Do diligent homeschooling parents find tutors for technical subjects they know they can’t properly cover themselves? Or perhaps do groups of parents help teach each other’s kids when for example one Mom knows physics quite well, and another child’s Dad is a history buff?
    (Is it even LEGAL for homeschoolers to be unofficially taught by another parent?)

  8. No question: public schools are a mess in this area. That’s why I suggested private schools, even religious schools (like the Catholic variety) that aren’t too extreme. As far as I am concerned, holding a degree in education (as currently taught, at least) should disqualify someone from teaching.

  9. Steve wrote: “Do diligent homeschooling parents find tutors for technical subjects they know they can’t properly cover themselves? Or perhaps do groups of parents help teach each other’s kids when for example one Mom knows physics quite well, and another child’s Dad is a history buff?
    (Is it even LEGAL for homeschoolers to be unofficially taught by another parent?)”

    Yes. Yes, and I’m the history buff, and who cares?

  10. RBT wrote

    “These bottles are Chinese-made, and they’re fine except for one thing. They arrive with the dropper tips and caps installed, which means that Barbara and I have to disassemble them all before filling and labeling them, and then turn around and reinstall the dropper tips and caps. Doing that for a few bottles is no big deal. Doing it for thousands involves some work.”

    You could outsource. Let some high school grad, or sociology PhD do the scutwork. They’d be glad of the work and income.

  11. brad wrote

    “As far as I am concerned, holding a degree in education (as currently taught, at least) should disqualify someone from teaching.”

    Oh come on! That’s just ideology talking.

  12. Well, that and the fact that education departments have by far the highest GPAs and by far the lowest SAT scores of any department in American universities. Obviously, there are exceptions, but basically the rule is that if you’re too stupid to attend college you can do it anyway and major in education.

    In a rational world, one would expect teachers’ mean IQ to skew right of center on the bell curve. I’d guess that it actually skews well left.

  13. Miles_Teg says: “brad wrote

    “As far as I am concerned, holding a degree in education (as currently taught, at least) should disqualify someone from teaching.”

    Oh come on! That’s just ideology talking.”

    And what’s talking that says teacher’s should hold BS degrees? Ideology!

  14. Sure, some teachers are out of their depth and some aren’t. I wouldn’t bother spending four years getting a BEd but my elder niece and younger nephew did and both are teaching primary (grade school level) at one of Adelaide’s best and most expensive private colleges. Apparently they’re both quite good at it.

    Some of my high school teachers were duds but about 3/4 were really quite good. I have very few complaints about my HS teachers. YMMV, of course.

  15. I think the issue here is that although some teachers are in fact quite good, it’s not because they have a degree in education, but in spite of it.

  16. As I understand it, to teach in a good UK state school, one needs a relevant degree *and* a PGCE (a qualification in education). I’m not convinced either way about the PGCE — I’d like to see more evidence that it improves people as teachers.

  17. Re Adam and Eve. I rather thought they had two sons that went into the land of Nod where they found their wives. Since Adam, Eve and their two sons were the only human beings on the planet at the time, presumably those wives were non-human primates (apes). So the Biblical account would appear to agree with the Darwinian account. What’s the beef? 🙂 [ducking and running]

  18. Well, the Adam & Eve myth is prima facie self-contradictory, so why not?

  19. The Bible mentions Cain and Able (and Seth, IIRC) by name but there were others, the KJV says “they begot sons and daughters”. So that’s where the wives might have come from.

  20. Well, I’m not sure how you came to that conclusion, but it seems likely that Adam and Eve’s sons mated with Adam and Eve’s daughters (and grand daughters, and so on.) It’s just incest, I’m surprised an anarcho-libertarian sex obsessed atheist would object.

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