Atlanta Metro Booming Update 3

Hello again.


Since my last update, I have collected all the demographic data that I will be using for this project. The IPUMS database from NHGIS proved invaluable in this task and I am indebted to that service. The data I collected are organized by census tracts, which are geographical divisions within counties that the census uses for greater geographic granularity. The data have attributes for race, gender, age, income, and a few more things that will allow me to analyze trends throughout the Atlanta region.

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Progress Post #3: A Very Rough Draft

Hello again,

So I have finished my rough draft. Just to reiterate my focus was whether happiness and enjoyment reinforce engagement in sexually selected behaviors. The behaviors I used as my examples were sports, art creation and viewing, and large-game hunting. Since these behaviors are not usually considered to be related to sexual selection I spent a substantial amount of my paper explaining how they can be viewed as sexually selected behaviors.  While I feel that my explanation on why these behaviors are sexually selected are solid, establishing causality between the behaviors and happiness seems to be impossible as I could only find correlational studies. This is understandable as I feel that a causational study that could cement my thesis would be hard to formulate due to the nature of my question.  Currently, I am debating whether or not to add a  paragraph about the lack of causational evidence available. I also feel like my focus is a bit unclear in my paper because I spend so much time talking about purely sexual selection and how the behaviors are sexual selection so I will be working on that. Under is an outline of my paper so far.

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Dark Humor Research Update #2

I have just closed my survey after collecting 172 anonymous responses. Out of the 172 responses, 53 respondents completed the entire survey. Although this indicates a completion rate of about 30%, I believe I can still analyze my results with significance since my completed sample size is 53 (Above the generally accepted n = 30 for statistical analysis).

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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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