1. Polarized Light Scattering
Topic 3 Part 3
Biophysics

2. More rigorous Treatment of Light Scattering
This is not a solution
Polarizability per unt volume is a tensor (matrix)
Transversality is ensured by

3. First Born and coupled dipole approximation
The first born approximation assumes the electric field inside the particle is equal to the incident electric field.
The coupled dipole approximation

4. Stokes Vector and Mueller Matrices
Stokes vector completely describes intensity and polarization state of light.
Mueller matrix is a transformation matrix that is a property of material object
Check out examples of both

5. Significance of Muller matrix elements in absorption and scattering
Absorption Scattering
See notes for more description

6. Measurement of Mueller matrix
Do simple example – like detecting M14. What kind of light do you put in?
Use photoelasatic modulator taking advantage of modulation technique to get good signal to noise.
d = A Sin(wt)

7. Apparatus Do examples Light source 90o Polarizer Sample Filter?
detector
PEM
at 45o
Do examples
PEM
Quartz (strain)
Apply ac voltage – piezoelectric crystal

8. Higher Order DNA Structure

9. Nucleosome www.answers.com

10. 30 nm fiber Crosslinker Solenoid
Crystal Structure supports cross-linker model
(Nature 436, (7 July 2005)
Nature Structural & Molecular Biology  12, 6 (2005)

11. Protein Scaffold

12. Function Lampbrush chromosome
Polytene chromosomes from salivary gland cells of Drosophila larvae. Regions of condensed chromatin appear darkly stained whereas regions of de-condensed chromatin stain lightly.