Effect of Temperature on Pulse Wave Velocity and Arterial Compliance
Tucker Frawleya and T. Brian Buntona
Dept. of Chemistry and Physicsa, Coastal Carolina University, Conway, SC 29528
The compliance of a material is the ability of the material to expand or contract. A low arterial compliance will lead to high blood pressure and, ultimately, cardiovascular disease. The velocity of the pulse wave traveling through an artery is a function of the compliance of the artery that it is traveling through. Therefore, the compliance of an artery can be indirectly observed by measuring several pulse wave velocities in the artery. This experiment investigates the effect, if any, of temperature on arterial compliance. Two electrocardiographs (ECGs) were taken from healthy human subjects at the right wrist to right elbow, before and after an application of a temperature gradient. For one study, the subject's arm was put into water of a significantly higher temperature than the body. For the other study, the subject's arm was put into water of a significantly lower temperature than the body. From the ECGs taken, the relative pulse wave velocities before and after the applications of the local temperature gradients were determined. It was determined that the local heating resulted in an increase in the pulse wave velocity in the artery, and the application of the local cooling resulted in a decrease in the pulse wave velocity in the artery.
compliance, pulse wave velocity, cardiovascular, thermoregulation
1. American Heart Association. "About High Blood Pressure (HBP)." Accessed March 3, 2013. http://www.heart.org/HEARTORG/Conditions/HighBloodPressure/AboutHighBloodPressure/About-High-Blood-Pressure_UCM_002050_Article.jsp
2. Najjar, Samer S. et al. "Pulse Wave Velocity Is an Independent Predictor of the Longitudinal Increase in Systolic Blood Pressure and of Incident Hypertension in the Baltimore Longitudinal Study of Aging." Journal of the American College of Cardiology 51 (2008): 1377-1383. Accessed March 3, 2013. doi:10.1016/j.jacc.2007.10.065.
3. Millodot, Michel. Dictionary of Optometry and Visual Science, 7th ed. Edinburgh: Butterworth-Heinemann. Elsevier, 2009.
4. The American Heritage Medical Dictionary, 2nd ed. revised.
5. Anderson, Robert M. The Gross Physiology of the Cardiovascular System. Tucson: Racquet Press, 1993. Accessed May 5, 2011. http://cardiovascular.cx.
6. Klabunde, Richard E. Cardiovascular Physiology Concepts, 2nd ed. Baltimore: Lippincott Williams & Wilkins, 2011. Accessed May 5, 2011. http://cvphysiology.com.
7. The UCSF Academic Geriatric Resource Center. Pulse Wave Velocity. Accessed May 5, 2011. http://agrc.ucsf.edu.
8. Bramwell, J. Crighton, and A.V. Hill. "The Velocity of the Pulse Wave in Man." Proceedings of the Royal Society of London. Series B, Containing Papers of a Biological Character, 93 (1922): 298-306.
9. Asmar, Roland, et al. "Assessment of Arterial Distensibility by Automatic Pulse Wave Velocity Measurement." Hypertension 26 (1995): 485-490. Accessed May 5, 2011. doi:10.1161/01.HYP.26.3.485.
10. Tozzi, Piergiorgio; Corno, Antonio; and Hayoz, Daniel. "Definition of Arterial Compliance." American Journal of Physiology – Heart and Circulatory Physiology 278 (2000): H1407. Accessed May 5, 2011.
11. Rhoades, Rodney A. and Bell, David R. Medical Physiology: Principles for Clinical Medicine, 3rd ed. Baltimore: Lippincott Williams & Wilkins, 2009.
12. Joyner, Michael J. "Effect of Exercise on Arterial Compliance." Circulation 102 (2000), 1214-1215.
13. Tanaka, Hirofumi et al. "Aging, Habitual Exercise, and Dynamic Arterial Compliance." Circulation 102 (2000): 1270-1275.
14. Charkoudian, Nisha. "Skin Blood Flow in Adult Human Thermoregulation: How It Works, When It Does Not, and Why." Mayo Clinic Proceedings 78 (2003): 603-612.
15. Sessler, Daniel I. "Perianesthetic Thermoregulation and Heat Balance in Humans." The FASEB Journal 7 (1993), 638-644.
16. The Gale Encyclopedia of Medicine, 4th ed.
17. Hast, Jukka. "Self-Mixing Interferometry and Its Applications in Noninvasive Pulse Detection." MSc, University of Oulu, 2003.
18. SinusRhythmLabels.svg. Accessed December 11, 2011. http://commons.wikimedia.org/wiki/File:SinusRhythmLabels-it.svg.
19. Skripkariuk, Daniel. "Development of a Pulse Wave Velocity Lab." Report, University of Western Ontario, 2009.
High Peak Power VCSELs in Short Range LIDAR Applications
Neil E. Newman1, Duncan C. Spaulding1, Graham Allen1, Mohamed A. Diagne1,2
1Department of Physics, Astronomy, and Geophysics, Connecticut College, New London, Connecticut 06320,
2Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02420
A technique for short-range LIDAR that monitors high-peak-power pulses rather than uniform square pulses is demonstrated using a commercially available Optek OPV310 VCSEL with a 10μm aperture operating at a wavelength of 850nm for applications in LIDAR-based active defense systems. Using 10ns pulses at a 0.1% duty cycle and 60mW of peak power, a target one meter away exhibiting Lambertian reflectance was detected with a 3:1 minimum signal-to-noise ratio in a narrow-field LIDAR setup using a 28dB amplifier. At 0.75m, using the same target and no signal amplification, a 2:1 minimum signal to noise ratio was achieved in a wide-field setup. These results establish the viability of commercially available low power VCSEL devices for LIDAR.
1. Geske, J., C. Wang, M. MacDougal, R. Stahl, D. Follman, H. Garrett, T. Meyrath, D. Snyder, E. Golden, J. Wagener, and J. Foley. “High power VCSELs for miniature optical sensors,” Proc. of SPIE 7615 (2010): 76150E-1–11, doi: 10.117/12.847184.
2. Geske, J., M. MacDougal, G. Cole and D. Snyder. "High-power VCSELs for smart munitions," Proc. of SPIE 6287 (2006): 628703-1–12, doi: 10.1117/12.679296.
3. Miller, M., M. Grabherr, R. King, R. Jager, R. Michalzik, and K.J. Ebeling. "Improved output performance of high power VCSELs," Selected Topics in Quantum Electronics, IEEE Journal of, 7,2 (2001): 210–216.
4. Michalzik, R., M. Grabherr and K.J. Ebeling. "High-power VCSELs: modeling and experimental characterization,"
Proc. of SPIE 3286 (1998): 206–219.
5. Moench, H., J. Baier, S. Gronenborn, J. Kolb, M. Miller, P. Pekarski, M. Schemmann and A. Valster. "Advanced characterization techniques for high power VCSELs," Proc. of SPIE 7615 (2010): 76150G-1–11, doi: 10.1117/12/839953.
6. Grabherr, M., R. Jager, M. Miller, C. Thalmaier, J. Herlein, R. Michalzik, K.J. Ebeling. "Bottom emitting VCSEL's for high-CW optical output power," Photonics Technology Letters, IEEE, 10,8 (1998): 1061–1063.
7. “Optek OPV310 Data Sheet,” Optek, Inc., Accessed May 10, 2012, www.optekinc.com/datasheets/OPV314.pdf.
8. “DET210 Data Sheet,” Thorlabs, Accessed May 10, 2012, www.thorlabs.com/thorcat/2200/2201-S01.pdf.
9. Aull, B.F., A. H. Loomis, D. J. Young, R. M. Heinrichs, B. J. Felton, P. J. Daniels, and D. J. Landers, “Geiger- mode avalanche photodiodes for three-dimensional imaging,” Lincoln Lab. J, 13 (2002): 335–350.
10. Kennedy, D.R., “History of the Shaped Charge Effect: The First 100 Years,” March 1990, Defense Technical Information Center, Accessed June 30, 2012, www.dtic.mil/cgibin/GetTRDoc?AD=ADA220095.
Spacecraft Approaching Technique
Harriet L Wilkes Honors College of Florida Atlantic University,
Department of Physics, Jupiter, FL
Using already established equations of motion for particles under a gravitational force, we analyze the motion of two spacecrafts in the same circular orbit approaching each other if one of the craft were to speed up or slow down. The purpose of this paper is to analyze and develop equations of motion for the transfer of spacecrafts from circular orbits to elliptical orbits with the intention of spacecraft approach. We can come up with a table of velocities that allow for a number of safe approaches for the spacecraft to take. We found that projecting a safe approach requires that we know the new speed of the transfer spacecraft, the desired change in distance between the two spacecrafts, and the magnitude of the radius vector of the perigee for the elliptical transfer.
Spacecraft, Particle Motion, Approach
1. Beer, Ferdinand P., and E. Russell Johnston. “Kinetics of Particles: Energy and Momentum.” Vector mechanics for engineers: dynamics. 5th ed. New York: McGraw-Hill, 1988. 729-826. Print
2. Celletti, Alessandra, and Perozzi, Ettore. 2007. “The Accessibility of Celestial Bodies,” Celestial Mechanics The Waltz of the Planets. 158-161, edited by R.A. Marriot. Praxis Publishing, Chichester, UK.
3. Hohmann, Walter. 1960. The Attainability of Heavenly Bodies, Washington: NASA Technical Translation F-44.
4. Resnick, Robert, and David Halliday, and Kenneth S. Krane. 1991. Physics, 4th Edition, Vol. 1. John Wiley & Sons, Inc. New York.