## Thursday, December 18, 2008

### Protein of the Day #15: Adropin

Recently in Cell Metabolism there was a very interesting article on the newly characterized peptide Adropin. Adropin seems quite important in regulating the balance between sugar and lipid use as fuels; its one of several promising avenues to understanding and treating diabetes that have come out in the last year or two. The peptide is cleaved from the product of the gene Enho (energy homoestasis associated). Its extremely well conserved in mammals - for most species the amino acid sequence is 100% identical (a few ungulates have 1 amino acid difference). Here is a picture of the conservation from UCSC's genome browser:

## Monday, December 15, 2008

### Coloring book reject

The image below is a Groebner fan that is just too complicated to put in the coloring book, buts I think its pretty impressive:

The ideal generating this is from what I call the "super three-vortex problem", the equations for the central configurations of a 1/r^2 potential:

I am mainly interested in the nonzero solutions of this system. To get at those, we can saturate the ideal - or in practical terms we can introduce a new variable, w, and add the equation w*s12*s13*s23 - 1 = 0  to the ideal. The 3D Groebner fan of the resulting system can be seen here.

## Thursday, December 4, 2008

### A mathematical coloring book

I've been working on a mathematical coloring book, with the pictures created using Sage. It still needs some work but I've put a preliminary version up at lulu.com. (I am not making any money on it, the cost is what lulu.com charges to print it.) I have also made the download freely available. I would appreciate feedback, especially from people with kids who try it out.