Thursday, June 30, 2011
Today in class, we learned about an important concept in economics known as the Marginal Propensity to Consume (MPC) and the multiplier derived from it. We can find the multiplier with a simple formula, but the tricky part is figuring out MPC because everyone has different opinions. We also covered the consumption function, investment spending, and inventories. Mr. Coleman handed out a worksheet on the MPC and consumption function, and he explained the answers after we finished. At the end of class, we continued watching Blood Diamond, which we will finish next Wednesday.
Our homework assignment is due tomorrow so I worked on it when I got back to my dorm after lunch. I finished the homework, but right now, I have four of my macroeconomics friends in my compact, single room reviewing the questions. Our group prides ourselves in being extremely diverse, with all five of us speaking a unique language. I love that our study group represents the diversity that is found at Brown. Three girls are from other dorms so they are frantically working to make it back before curfew. We are being quite loud with our studying, but we will quiet down soon as our floor mates are heading off to bed.
I need to get more sleep. As much as I try, I can never sleep earlier than midnight, giving me less than eight hours of sleep as I have to wake up at 7:45 AM for class. Class is not boring at all, but I sometimes feel weary from my insufficient amount of rest. Occasionally I will try to nap but very shortly. I know that college will be like this too, probably even more exhausting. I don’t plan on sleeping much in college, and I will cherish sleeping in on the weekends. Speaking of sleep, it’s time for bed.
The first lab began with incubated white blood cells from the previous day. The first step of the lab was to isolate the DNA by degrading the proteins that surround the DNA—cell membrane, nucleus—and bind the DNA—histones, methyl groups, and epigenetic proteins. This involved centrifuging to separate proteins that are cut by an enzyme added to the DNA. Protein collected at the bottom of the tube, and the liquid above the protein pellet contained the DNA from the white blood cell. Then to transfer the DNA from the solution, ethanol is added and the DNA is moved to another tube to be prepared for incubation and then a protein analysis, which is Protocol 3.
Unfortunately, my DNA was not visible in the ethanol solution; instead of proceeding to the incubation, I had to follow the procedure used to separate the plasmid of transformed E. coli cells from an enzyme solution. This included centrifuging the tubes—I made two tubes when I was adding the ethanol because the TA thought I did not put enough ethanol to precipitate the DNA—then pouring off the excess liquid and waiting for the liquid to dry. I was successful in salvaging my DNA, but I will not know whether I purified my DNA today.
Simultaneous with the lab purifying my blood, I also had to purify bacterial DNA as I noted above. Often I found myself at an impasse because both of my labs steps were conflicting. I followed the same steps as the supplemental steps: I had to follow in extracting DNA from white blood cells, but I added solutions in smaller quantities.
Even though I was rushing to get the timing in sync, I enjoy learning how to purify DNA, and as Ms. Hall noted, purifying plasmid is a powerful asset for someone who wants to work in a lab and get paid.
After class I was fortunate enough to study with my amazing group mate by the name of Erin Miller. We studied and did intense work on our tedious homework assignment. It is great that Brown has so many places for studying. We were in a large room all by ourselves, and this allowed us to optimize the work we did. It was good to work with someone on this homework being that it was very tedious. I feel that we about mastered the assignment so I sense a check plus coming our way.
After studying Erin I talked to my friend Milani Lyman who is at Columbia. We discussed some similarities and differences in our programs. Also we talked about our experiences so far and what we think of the East Coast. It was great to converse with a fellow Ivy League Connection member at a different program. By talking to her I felt that I too was immersed in “the city that never sleeps” at Columbia University. Even though I have never visited, from what Milani tells me it is a great college. I will have to do my research to further wet my appetite for this college.
A lot of the lab procedures are new and challenging for me. I worked under sterile conditions for the first time, and our teacher congratulated our lab group on not contaminating our solutions. Today, I felt really good about the lab. I followed the procedure stringently, and was one step ahead of the game. I finished early, but I was afraid that I had ruined my results.
Afterward, I studied extremely hard with my friend. I read many science articles and prepared myself for the quiz on Friday. The class is very challenging and it is fun, but we have not experienced many lectures. This embodies the practicality of this field and shows the necessity of skills in the lab. Science intrigues me more because of these experiments. The lab work at Brown is much more difficult than that of the classes at Pinole Valley.