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Jai Mata Di The Mechanism for Defocus-driven Occular Growth

Jai Mata Di The Mechanism for Defocus-driven Occular Growth. The Eye. www.ahaf.org. Lens . Power ( Diopters ) focal length (metres) 1 D 1 m 2 D .5 m Convex lens (has a positive power e.g +1.5 D) focal point forms convergent light

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Jai Mata Di The Mechanism for Defocus-driven Occular Growth

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  1. Jai Mata Di The Mechanism for Defocus-driven Occular Growth

  2. The Eye www.ahaf.org

  3. Lens • Power (Diopters) focal length (metres) 1 D 1 m 2 D .5 m • Convex lens (has a positive power e.g +1.5 D) focal point forms convergent light • Concave lens (has negative power e.g -2D) focal point is traced back from diverging light

  4. http://www.math.ubc.ca/~cass/courses/m309-01a/chu/MirrorsLenses/lenses.htmhttp://www.math.ubc.ca/~cass/courses/m309-01a/chu/MirrorsLenses/lenses.htm

  5. Lens Accommodation http://www.sapdesignguild.org/editions/highlight_articles_01/images/accomodation.png

  6. Disorders of optics of eye • Emmetropia (normal vision) • Myopia (short sightedness) • Corrected with negative power lens • Hyperopia ( Longsightness) • Corrected with positive power glasses • Presbyopia (age-related changes) • Range of accommodation depletion • Multifocal or bifocal lens correction

  7. Visual Abnormalities http://www.merckmanuals.com/professional/sec09/ch099/ch099a.html

  8. Retina/RPE/Choroid http://www.maculacenter.com/LightBox/glossaryImages/rpe.jpg

  9. Retinal Pigment Epithelium Crucial for the maintenance of photoreceptor excitability • The main functions of the RPE are the following: • (1) Transport of nutrients, ions, and water • (2) absorption of light and protection against photooxidation, • (3) reisomerization of all-trans-retinal into 11-cis-retinal, which is a key element of the visual cycle, • (4) phagocytosis of shed photoreceptor membranes, and • (5) secretion of various essential factors for the structural integrity of the retina.

  10. SUPER PROJECT • Nernst– Artificial Membrane • Diffusion of Ions • Is there a transport of water? • Stepper Motor – Servo System • Pusing in and pushing out fluid • Voltage Clamp • Using fixed voltage and determining how much to change to determine a transmission response • Fluid Flow • Voltage Clamp • Chamber • Artificial Membrane

  11. Artificial Membranes: How they are made? • Usual method is to have a 2 mm diameter hole in teflon sheet between aqueous solutions. Place 1 drop of (say) phospholipid in dodecane on hole and allow it to thin (as one would a soap bubble). Eventually get an optically black lipid bilayer film. Why use Artificial Membranes? • Calibration

  12. ‘Nernst’

  13. ‘Puddle’ • Stepper Motor – Servo System • Pushing in and pushing out fluid Sensor Engineered by David

  14. ‘Stepper’ • Stepper Motor – Servo System • Pusing in and pushing out fluid Engineered by David

  15. ‘Puddle 2’ - also using an artificial membrane

  16. RC-50 Imaging Ussing Chamber

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