Math Major Monday

The other day I was doing some prep work for my current project and was making up the tubes I need to make dilutions for spread plating. If you click that link note that it is one of my first videos and so I was still working on the whole learning to talk coherently and do lab work at the same time, lol. Oh and I plan to bring Guess that Gizmo back I just have been busy and it was not getting the response I wanted so I kind of put it on the back burner figuring I might pick up a few more readers and revive it.

Back on track. I was doing this prep work and one of the first thing one should do while doing prep work is to figure out how much of something you need. I have become a white board addict for this kind of task, don't waste paper and it is quick and easy to correct errors. The lab has a big one but lately it has been filled up with the chicken scratches of the lab jerk (he makes my crappy handwriting look good!). For that I am not really faulting him since I am as well, I tend to be less of a hog about it. It just so happened though that I had gone shopping at Cubs, which used to be the place I bought most of my groceries but the opening of the Super Walmart has changed my life forever, one stop shopping is a beautiful thing! Since I was in the area though I decided to snoop around Cubs and found a dollar bin, I am a sucker for those, LOVE the ones at Target! They had these little white boards, pretty crappy but only a dollar, I decided to get it for the lab and imagined using it to harass people. Well between lab jerk hogging the white board and me liking to have reminders to help me not miss something on a long day I've basically only used it for legitimate reasons. This day I used it to write out the calculations for figuring how much peptone water (water with stuff in it so it is gentle on the bacteria) I needed to make. Here is the picture of it with the calculations all written out:

I promise you that 3000ml (3 liters), is the correct answer. There are 72 tubes per rack. If I have any engineers I think some of them would get it and the rest are likely convulsing on the floor. I wrote it out and afterwards decided it looked funny, makes perfect sense to me but to an outsider it probably looks like a math FAIL. Anyone want to take a stab how someone with a bachelor of science degree and a calculator managed to make 1300+1440=3000? And no, it is not an example of my having lost my sanity, though the lab jerk has been pushing it to its limit lately. I keep reminding myself that the prison probably wouldn't let me have much internet access and that Doc actually checks the police blotter to see if any of his patients did something stupid (he told me after I expressed my semi-joking wish to hit lab jerk with a rolled up newspaper). I was instructed not to get my name in the paper, being the super compliant patient that I am I did actually get my name in the paper that week, just not the blotter, lol!

My boss saw it before I did and now won't stop harassing me to get going on writing up the current experiment, get the stuff that does not involve the data and data analysis written up now, so not my style though, especially after a long day in the lab! Good thing she does not know about the bloggity! Though this is seriously very very different writing wise and I am using this to try and help me sharpen up my writing skillz a bit since it has been awhile since I took a course that required that much writing and I am incredibly intimidated by this technical/scientific writing thing. I have never really done it before, my one attempt I felt sucked really bad, so it is kinda scary, but I will figure it out and she will help by ripping it to shreds until I get it right! Hopefully it won't be too bad, we shall see. Between that, and lab work, and twitter/facebook I have not had as much time for blogging, both as a writer and a reader and am behind on both, miss you all and I will eventually catch up with reading and am trying to make sure I post once in awhile so you all don't think I died or something.

One last thing before I crash, on twitter a few of us were chatting and Flat WeaselMomma came up and McMommy decided she wants to host FWM (that would be so cool) and then she started contemplating making a Flat McMommy and sending her up to hang out with the Weasels. Then the idea snowballed and she wants to come visit me and hang out in the lab too! I totally played it cool and was all saying it could be arranged but I was totally doing the excited tween girl contemplating meeting a Jonus brother or something tweens are into these days!!!!! I'd consider Flat Microblogologist but it would cause Baby Sibling to make fun of me since I am already flat, she got almost ALL the boob allowance for our family and did not leave much for Middle Sister and I, Middle Sister is the one that actually wants it too! Anyone have any ideas for what I should do if and when Flat McMommy comes to visit? For sure she'll join me in the lab but I have to show her more than just that. Something fun to think about =)

Spread Plating and Guess That Gizmo

Before I showed you streak plating, that is a method that is often used when checking for contamination and is supposed to result in isolated colonies that originate from a single organism that lands on a spot and grows there until it forms a visible area of growth in the form of a dot. Spread plating is a very common method that is used to enumerate the bacteria in a sample. Most of my studies have to do with how well my bacteria survive in different environments and so I do dilutions to get a smaller number of bacteria per mililiter and spread plate the dilutions and see how many colonies I get, the concept behind said colonies is the same as for streak plating.

The two dilutions I commonly make are 1 in 100 (1 part of sample into 99 parts diluent) and 1 in 10. When I plate the sample I plate 0.1 ml so that adds another 1 in 10 dilution in the end. I multiply the number of colonies on the resultant plates by the number of times I diluted and it gives me the number of cells per ml in the original sample. Not diluted enough the bacteria form a smear across the plate, if too diluted then only a few colonies if any are present, I want approximately 20-250 colonies to have what is considered statistically significant results. And at risk of losing all of my beloved readers and having Baby Sibling make fun of how incredibly dorky I am I have made a video of me doing a dilution set and spread plating it:

Here are two plates, the one on the left I used the spread plating technique and the one on the right I streak plated:

You are still here??? Great! Now that you have gotten to laugh at me how about giving me a laugh or two (with you not at you), it is time for the next Guess That Gizmo!
Sorry about the not so sticky biohazard sticker, they just don't make 'em like they used to I guess:
And remember, this is a semester long contest so new readers can participate too, here are the rest of the Fall 2008 Semester GTGs:
Gizmo 1
Gizmo 2
Gizmo 3