Tuesday, 31 January 2012

08:22 – I just filed my North Carolina E-500 Sales Tax report. As always, I deeply resent being forced to function as an unpaid tax collector for the state of North Carolina. North Carolina already has self-reporting of use tax for out-of-state purchases. Why can’t it do the same for sales tax on in-state purchases? This shouldn’t be my problem.

I’m still going through the book session by session, listing what’s to be supplied with the biology kits. Once I get a final bill of materials, I can start generating POs for the components I need to order and then build a prototype kit to figure out what size box we’ll need, how the stuff will be packaged, and so on. Then we can get the first batch of 60 kits actually built.

Meanwhile, I’ll be juggling edits on the biology book with a re-write of the forensics book to make it kit-based.

Monday, 30 January 2012

10:28 – The book is complete and off to the editors. For the next few weeks, I’ll be working with the editors and layout/design folks, answering queries, incorporating edits, and otherwise cleaning up before the book actually goes to print. I also have some book-related stuff to do. For example, we included a link to a biology landing page on thehomescientist.com website, which has to be created, along with all of the pages that it links to.

Starting today, I’m going through the manuscript. Each lab session has a list of items required, separated into groups of those included in the kit and those the reader supplies. I have to consolidate those lists so that I can come up with a final BoM for the kits. I’ll also consolidate the user-supplied item lists so that readers will have a single list of items they’ll need to acquire.

I’d thought about including a basic set of ten or so prepared slides as a standard part of the kits. I decided against that, mainly because some readers may already have prepared slide sets, and it makes no sense to duplicate. Instead, I’ll do what I originally planned, and make a core slide set an optional item, or indeed possibly a separate SKU. The slide set may or may not be available initially with the kits. Obviously, there are many sources for prepared slides.

The other reason I need to get the kit BoM finalized is so that I can do some price and cost calculations. At this point, I don’t have a firm idea how much the kits will cost to build or how much we’ll need to charge for them. My original goal was $175 or less with shipping but not including prepared slides, and I’d like to keep it to $160 or less if possible. There are many variables to consider, not least the physical size of the kit. If it’ll all fit into a USPS Priority Mail large flat-rate box, for example, I know my shipping costs will be about $15 per kit, regardless of weight or distance. If it won’t fit, I’ll have to buy regular boxes at maybe a buck or so each delivered and pay PM weight/distance rates, which’ll vary according to how much the kit ends up weighing and how far it’s going. In that case, assuming the kit weighs 10 pounds, my average shipping cost is going to be a good bit higher. I could use parcel post, which would cut the shipping cost significantly, but at the expense of typical 7 to 10 business day delivery time rather than the 1 to 3 days with PM. I suspect most kit buyers aren’t going to want to wait.

Sunday, 29 January 2012

08:51 – We should finish the manuscript today, with two days to spare. Barbara is cleaning house this morning and then heading over to her parents’ house for lunch. We’ll shoot the final images this afternoon.

While I was doing laundry yesterday I had a few minutes to spare so I decided to make up the eosin Y stain for the biology kits. Eosin Y stain sold by most lab supply vendors can be anything from 0.2% to 1% eosin in either water or alcohol. Normally, the only other component is a preservative to prevent mold growth, usually a pinch of thymol or a few drops of chloroform per liter. But I’d been doing some research, and it seems that acidifying the stain with 1% or so acetic acid gives much better results.

So I dissolved 5 grams of eosin Y in nearly a liter of distilled water. It formed a very dark red solution that was so intensely-colored it was opaque even holding the bottle up to a strong light. I added 10 mL of glacial acetic acid and was surprised to see a distinct color change to almost orange. I’ll have to do a comparison test with the acidified eosin Y against neutral aqueous and alcoholic eosin Y before I use this for kits, but I suspect it’ll work very well.

Saturday, 28 January 2012

10:41 – All of the chapters are complete and off to the editors except the Introduction, which is in progress now. This weekend, we need to shoot some images to replace placeholders in the text. We also need to build the gel electrophoresis apparatus and run a gel or two.

Monday, I start going through the manuscript chapters to build a list of what’s to be included in the biology kit, including amounts. Once I have that, I can start generating purchase orders for the materials and start actually making up chemicals, printing labels, filling and labeling bottles, and so on.

I’ve also decided to offer two options with the biology kit. First, a simple hand microtome. Second, a core set of maybe 20 to 25 prepared microscope slides. For those, I’ll focus on slides that are particularly important, hard to find elsewhere (particularly in standard sets), and difficult to prepare yourself (sections, special staining, and so on rather than simple whole mounts of common things). I’ll also focus on double- and triple-purpose slides. For example, a lot of slide sets include cross-sections of monocot and dicot roots, stems, and leaves, along with slides showing skeletal, smooth, and cardiac muscle. That’s nine separate slides, but I can do the same thing with only four slides: monocot and dicot roots on one slide, monocot and dicot stems on one slide, monocot and dicot leaves on one slide, and three types of muscle on one slide. The individual combined slides are usually a bit more expensive than single-specimen slides, but nowhere near twice as much.

One of the wholesalers I’ll probably buy some of those slides from packages them in boxes of 50 of the same slide, so I’ll put 50 sets together initially. I have no idea what percentage of people who order the biology kit will want the optional prepared slides, but I suspect 50 slide sets will suffice for the first 60 kits, if not many more. Delivery time on the slides is typically 60 days ARO, so we may have some juggling to do. That delivery time means I also need to get the slides on order no later than mid-February if I want to have them available by mid- to late April.

Friday, 27 January 2012

08:09 – I should finish the lab session on simulated DNA gel electrophoresis today and get it off to the reviewers. Finish in the sense of finish writing it. I haven’t actually done the lab session yet. I’ll do it this weekend, when we’ll also be shooting a lot of images for it and other lab sessions. That leaves only the introduction, which is in progress. It looks like we’re actually going to make the 31 January deadline.

Not that things settle down much after that. In addition to a flow of of queries and edits, I have to get the kit contents finalized and purchase orders cut for components. The biology book hits the bookstores in April, and by that time I want to have 60 finished biology kits in inventory and ready to ship, along with components in the pipeline for many more.

The next project is a complete re-write of the forensics lab book that we finished a couple of years ago but was never published. I want to rewrite that book around a custom kit, which will make it much more accessible to home schoolers and hobbyists. I’d like to have that book complete, at least in PDF form, and kits available in time for summer session, although realistically it’ll probably be in time for autumn semester.

Farther out, but still on the horizon, I’d like to do a second edition of Illustrated Guide to Home Chemistry Experiments, this one kit-based. Two kits, actually. One for first-year labs (the current chemistry kit) and one for second-year.

It’s going to be a busy year.

Thursday, 26 January 2012

08:44 – I sent off the preface and lab safety chapter to the reviewers yesterday. That leaves the introduction, which is well in progress, and a lab session that I wasn’t sure I’d have time to do before deadline. That one is on simulated DNA gel electrophoresis, “simulated” because we’ll use dyes rather than actual DNA fragments for the separation.

Those dyes–crystal violet, methylene blue, and safranin O–are included in the kit as biostains, and they all migrate the same direction in a gel. We’ll use their different molecular masses as proxies for DNA fragments of differing BP size. We’d use real DNA, but that’d require expensive restriction enzymes, and wouldn’t produce very distinct banding in an agar gel (as opposed to agarose, which is much, much more expensive than agar, which isn’t cheap itself). I was thinking about having readers pre-run the gels to clear out some of the gunk that’s present in plain agar, but that’s really more trouble than it’s worth.

Wednesday, 25 January 2012

07:49 – Heads-down writing continues, as it will for the next several days.

I was just reading an article to Colin yesterday about new evidence that dogs have been man’s best friend for at least 33,000 years, back when we were still Cro Magnon. Two skeletons of what are unquestionably domesticated dogs have been reliably dated to 31,000 BCE. To put that in perspective, it wasn’t until about 11,000 BCE that man domesticated the sheep, pig, and cow, and it wasn’t until about 6,000 BCE that women domesticated men.

Monday, 23 January 2012

11:12 – With eight days left until deadline, I’m in serious heads-down writing mode. The lab sessions are complete, with one exception, and I’m working on the narrative early chapters now. There are four of those: Preface, Introduction, Equipping Your Lab, and Lab Safety. I’m working on the Preface now. The chapter on Equipping is essentially complete. It’s currently 51 manuscript pages and about 25,000 words, and I want to cut that down some. Lab Safety is reasonably complete, but needs a few more hours work. The Intro is the one that’ll take me two or three days to finish. So I’d better get back to work.

Sunday, 22 January 2012

11:39 – While she was watching basketball yesterday, Barbara finished packing and labeling 60 each of five groups of solids: amoxicillin capsules, ascorbic acid tablets, dextrose, lima bean seeds, and carrot seeds. She’ll finish up agar and Rhizobium innoculum today.

I took a break from writing to do some stuff in the lab. I wanted to have several solutions ready for packaging after deadline. Unfortunately, some stuff doesn’t go into solution very quickly. For example, even with constant agitation and warming, copper(II) sulfate takes a long time to dissolve. I make up one molar solutions of that for the chemistry kits, which is about 500 grams of the pentahydrate dissolved and made up to two liters of solution. I finally gave up trying to get the stuff to dissolve faster. Now, I just transfer 500 grams of the salt to a clean two-liter soft drink bottle, fill it up most of the way with distilled water, and just invert the bottle a few times any time I think about it. It takes several days to a week for the salt to dissolve completely.

Some stuff that goes into the biology kit worries me a bit in terms of dissolution speed. One of those is Sudan III stain. Some vendors sell what is supposedly a 1% solution of Sudan III in isopropanol. I’m not sure how they do that. The best figures I can find say that Sudan III is soluble only to about 0.2% in alcohol, and nearly insoluble in water. (That’s certainly true; adding a tiny amount of Sudan III powder to some water yields a barely pink solution with undissolved solid on the bottom of the container.)

Anyway, some of these vendors include images of the bottle, which makes it very clear that the concentration is nowhere near 1%. Here, for example, is the Home Science Tools page for Sudan III. The stuff is pinkish orange in this image. According to the MSDS, the solution is 1% Sudan III in 99% isopropanol. I don’t see how that’s possible. The best I can do is about 0.2% in 99% IPA.

And isopropanol isn’t the best choice of solvent for Sudan III. A better choice is 50% acetone, 35% IPA, and 15% water, by volume. Conveniently, that means a 1:1 mix of acetone to 70% IPA. So I just went down to the lab, measured 500 mL of acetone into a clean one-liter soda bottle, and added 2.0 grams of Sudan III powder. The solution was immediately intensely colored blood-red, and opaque even when I held the bottle up to the light. I made up the solution to one liter with 70% IPA, at which point it was still so intensely colored that it was opaque to direct light. And, not all of the Sudan III had dissolved, although I had to invert the bottle and look at the powder still in the bottom to see that dissolution was not complete. It’s possible the remainder will go into solution over time, but it doesn’t really matter to me. I’m labeling the Sudan III bottles in the kit as “saturated” rather than with a percentage. That means all I need to do is keep some Sudan III powder visible in the bottom of the stock bottle. When I need more stain solution, I can just add more 1:1 acetone:IPA to the bottle and make sure there’s still undissolved solid present.