Post #2

In the first stage of my research, I went one-by-one through some of the existing economic studies that statistically and empirically evaluated the effects of right-to-carry, shall-issue, and concealed handgun permit laws on crime rates in the United States over the past several decades. My main takeaway from this initial stage of research was that there is a lack of consensus among the research community on the effects that these laws have on crime in our country.

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Post #2: Week 2 of Zebrafish Research Complete

Week two is now finished, and the data has been very exciting in terms of supporting my project advisor and I’s hypotheses! By quantifying phenotypes on a spectrum from normal to severe, I was able to generate mathematical support for the observations I have made thus far. Instead of just describing the trends I have seen qualitatively, I can now run statistical tests and provide charts that further demonstrate how the trends can be quantified. At this point, I have a lot of data and a lot of photos to analyze, so going forward I will be taking time to go through the information while completing my final week of experimentation. It is clear that I will need to take time after the actual lab work is complete to finish going through this data, writing a scientific-style paper, and making my final conclusions, but for now I can talk about what I accomplished in week two.

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Post 2: Immunocontraception and Chemical Sterilization

This update is marking the soft conclusion of my research. I’ve read many articles on different chemical sterilization techniques and have discovered why they are not frequently used. There are three major categories of chemical sterilization: hormonal down-regulation, immunocontraception, and chemmosterilization.

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Modeling Crystal Structures

The idea behind x-ray crystallography is that focused, collimated x-rays diffract off of clouds of electron density in a calculated manner defined by the Bragg equation. By measuring the intensity of these reflected x-rays, we can reverse engineer a 3D lattice from sets of thousands of diffracted spots, called reflections. My last post detailed some of the more physical skills related to crystallography, but I completely neglected to mention one of the greatest programs ever created for crystallography: SHELX. SHELX was developed in the 1960s and 1970s. It was coded in fortran wth the goal that it could be completely self-contained. This occurred at a time when the Internet was in its infancy, so everything that crystallographers used had to be independent. Keep in mind, this was originally stored on perforated paper tapes! SHELXLE is the GUI that crystallographers use today for refining structures. Fortunately, it lets you see the 3D visualization after every iteration. (The original version required crystallographers to print out a paper with numbers in the exact location of each atom from a specified orientation, so this is much more user friendly.) The goal of refinement is to match the measured electron density with positions of molecules in the lattice, while realistically describing how atoms interact. This is very different from simply reading off a graph because the data is coming in three dimensions of space and it extends ad infinitum. It is important to remember that the refinements are attempting to match all of space with the average unit cell. Sometimes free variables must be added and refined to proportions that describe how likely a certain arrangement is.

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