After getting a sizable portion of ablated embryos fixed in ethanol at the necessary stages (st. 18 and st. 30), in situ hybridization is necessary to determine the gene expression patterns in the embryos. This procedure works by linearizing a large amount of plasmid DNA grown from E. coli cultures. E. coli is used to gather a large amount of DNA for use because they reproduce quickly. After linearizing the DNA, transcription is done in vitro to create antisense RNA that will bind to the location of the RNA for the gene of interest. This RNA is then labeled with fluorescent or colored probes so that the signal can be observed. The genes of interest used in this experiment are XCG-1, Otx2, En2, and Krox20. These are various neural marker genes that are expressed early and later in development. A control group of embryos also undergoes the hybridization procedure as a control to show where normal expression occurs in these embryo stages.
When looking at the value of anything, we can take two approaches. The first approach: straight forward reasoning. If a bottle of water costs slightly over two cents to make, then its value should be right around that amount. The second: the free market approach. If people are willing to pay $4.25 for a bottle of water at the movie theater, then the bottle of water should be valued at $4.25. [Read more…]
Essentially, colleges across the United States are getting millions of dollars of gratuitous advanced military-grade weaponry every year; though technically there is no concrete data available to the public regarding weapon specifics, an even more concerning prospect. The equipment ranging from M-16’s to grenade launchers to armored vehicles is available for campus use. However, if the need arose, the equipment could also be used by the local community or even regionally.