1. Esther Johnson Physics, Del Rio High School Dr. Alvin Yeh, Associate Professor of Biomedical Engineering Dr. Arne Lekven, Associate Professor of Biology

2.  Noninvasive  High resolution  3D Images  Two Photon Fluorescence  Second Harmonic Generation (SHG) Setup

3.  Embryos are large, robust and transparent  Easily observed  Embryonic development occurs rapidly  Embryos are easily manipulated

5.  Yuqiang Bai - Biomechanics  Macroscopic Properties of Engineered Tissue  Microscopic Properties of Extracellular Matrix Various stretch ratio 1.0:1.0 1.1:1.01.1:1.1 1.2:1.2 1.2:1.1 Photos courtesy of Yuqiang Bai

7.  Connecting molecular and cellular biology  Biomechanics  Engineered Tissues  Stem cell replacement therapy  Cancer research  Various other biomedical arenas

8.  TAKS Science Objective 5  Physics TEKS c.3.E, F c.6.B,E

9.  Research: focus on biomechanics  Correlation  Elasticity  Hooke’s law  Test the biomechanical properties of “engineered skin tissue” Photo courtesy of http://hyperphysics.phy-astr.gsu.edu/hbase/permot2.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/permot2.html

10. Memory metal spring.wmv

11.  Hook Activity: Demonstration of Nitinol Spring vs. Regular Spring Ask students why there was a difference  Notes on Elasticity and Hooke’s Law  Homework (research assignment) Students must go home and research Nitinol springs

12.  Elasticity: the property of a substance that enables it to change its length, volume, or shape in direct response to a force effecting such a change and to recover its original form upon the removal of the force (dictionary.com)  Hooke’s Law or Elasticity F = -kx  F = restoring force exerted by the spring  k = spring constant  x = displacement of the spring end from its equilibrium position

13.  Hooke’s Law computer simulation  Homework: Hooke’s Law practice problems http://phet.colorado.edu/sims/mass-spring-lab/mass-spring-lab_en.html

14.  Hooke’s Law Lab  PowerPoint on my summer research experience Photo courtesy of Wikipedia Photo courtesy of JL Stanbrough http://www.batesville.k12.in.us/physics/phynet/mechanics/newt on3/Labs/SpringScale.html

15. Stretchiest skin - Guinness World Record2.wmv

16.  Engineering Challenge: design a mechanism to test the stretch vs. strain on skin-like materials compare the graphs from engineering challenge with graphs from the Hooke’s Law lab  Background: Human Skin  Must be elastic  If not, it would tear Photo courtesy of exorgroup inc.

17.  Can synthetic skin handle the same kinds of stressors as its biological counterparts? Human skin is considered “viscoelastic” meaning it demonstrates both viscous and elastic properties while it is deformed Graph courtesy of http://www.engin.umich.edu/class/bme456/ligten/ligten.htmhttp://www.engin.umich.edu/class/bme456/ligten/ligten.htm

18.  Students must design a mechanism to compare the various “skins” to identify which most closely resembles human skin Photos courtesy of http://www.purdue.edu/uns/html4ever/0002.Badylak.SIS.html and http://childrenshospital.org/newsroom/Site1339/mainpageS1339P223.htmlhttp://www.purdue.edu/uns/html4ever/0002.Badylak.SIS.html http://childrenshospital.org/newsroom/Site1339/mainpageS1339P223.html

19.  The stress/pull on the fabric must be equally distributed over a cross-section  Material must be immobilized on the other side  Material cannot be torn or the test has failed  Students must decide which material presents a stress-strain graph which most closely resembles human skin’s stress- strain graph.

20.  Various material squares (wool, spandex, cotton, rubber, leather, etc)  Ruler  Hanging Mass Set  Wood blocks  Pulley apparatus  Cardboard  Masking tape  Wire hangers  Paper clips

21.  Post-Test (identical to pretest)  Closure/ Discussion

22.  Students will Be able to manipulate the Hooke’s Law equation. Analyze and verify Hooke’s Law. Explore the field of Biomedical Engineering Identify practical applications of physics in engineering Design a Biomechanical testing device Evaluate and rank the biomechanical properties of various materials

23. Yuqiang Bai Kirsten Brink