Monday, April 11, 2016

Random Thoughts about never ending variables

I stand in front of the scale, the taping of my foot keeps pace as Panic at the disco serenades about the end of one life and the beginning of the next, as I grab a weigh boat and place it on the device. The directions on the protocol I’ve glanced over instruct me to add 20g of powder per liter of water. When I tap a button on the machine the tinged display on the tiny unassuming scale blinks a few times before 0.000gs springs up. I began to dole out the cream powder onto the plastic scoop, dust started to fill the air as the numbers slowly ticked up; 22.434, 23.675, 24.231. I stop adding as the numbers on the scale approach 25gs. 24.953, 24.967, 25.042, 25.078. I curse at no one in particular as the number exceeds 25gs. Of course it goes over, it always goes over. This scale is too perfect, too sensitive, I’ll never be able to achieve 25.000s exactly. The very air itself seeks to disturb my perfect number. I look across the lab where the other scale rest. Its duller, older, lacks the features this one possessives. Its also less accurate, its digital display flashing 0.0g. I begin to adjust; 25.054, 25.012, 24.85. This time I'm under. I could move to another scale, however, even though I could get to display 25.0g but it would be falsehood, lies to tell myself that I'm as accurate as possible. The actual chance I would hit 25.0gs exactly approach 0. I sigh and continue my adjustments...

The musical stylings of Lupe were softly buzzing in my head as I stared at the mice in the cage in front of me. They were scampering around the cage, their eyes peering out into the biosafety cabinet. Another day, another recording of body weight. I place a plastic bucket on the scale and grab a mouse #3, purely by random chance I tell myself, and place it in the bucket. The numbers on the scale dance around as the mouse moves, distorting my reading. I make a judgement call and write down a number. I compare it with the readings I took the other day, another decrease, clearly the DSS treatment I'm using is having an effect. Protocol guidelines demand euthanasia upon 75% weight loss. I pull out y phone and try not to get side tracked from Ms. Gilstraps email regarding up coming film seminars. I punch in the numbers on the calculator app and read the results; mouse #3 has yet to reach the termination point, but he’s close. I wonder how they determine that threshold between life and death. Its not like a mouse is healthy at 75.000001% and then turns deadly sick at 75.0000% of initial body weight. It’s a continuous spectrum with In any case, it’s not my judgement call to make. As Kendrick beings to warn me of the perils of swimming with a golden flask I select the next mouse…

I look at the plate full of mouse serum in front of me. If the experiment worked as I predicted, half of the samples should be full of FITC-dextran, at least in theory. Unfortunately, I’m incapable of emitting wavelengths high enough to excite the FITC nor are the photoreceptors in my eyes able to quantitatively to discern the magnitude of the response. Good thing I’m not alone, I place the samples into the plate reader and watch it enter the machine. It hums and beeps as it reads, while imaginary dragons tell me of apologizes while on their trip to Amsterdam. The machine stops and it spits out some numbers at me. I blankly stare at the numbers before focusing on my control and then looking back at my experimental samples. The difference in numbers brings a slow smile creeps upon my lips. I export the data to excel and analyze to get the quantity of FITC-dextran in serum. The smile fades, the difference between my groups isn’t as large as I previously surmised. I stare at the numbers again, its small but there is a difference. How do I quantify it, slight? Modest? I fight the urge to look up an online thesaurus. I must define a cut of, group them somehow, define where leakage begins and where it ends. But how? If the difference was extreme this would be simple but here there isn't a magical number I can point to and declare the boundaries. It’s a range, a spectrum. I could categorize it somehow, but I would lose information. Is that information valuable? How do I determine what is or isn't? I stroke my chin and ponder...


1 comment:

  1. I liked how you linked your topic back to your current lab work. I think that everyone can relate to trying to get a perfect measurement on the scale.

    Your post also shows the importance on performing statistical tests before making conclusions on your data. Even though you physically saw a difference, it wasn't as large as you originally believed. Analysis of the data could reveal a significant difference, or it could not.

    ReplyDelete