Sleiman Ghorayeb - Recent Selected Publications

Recent Selected Publications Journal Articles 1. Sethna CB, D Kee, P Casado, M Murphy, L Palmer, SR Ghorayeb, and B Morganstern. “Renal Sonographic Changes in Heterogeneity Index and Echogenicity in Children with Hypertension: A Novel Assessment,” Journal of the American Society of Hypertension, Vol. 12, No. 12, pp. 77–83, December 2018. DOI: https://doi.org/10.1016/j.jash.2018.11.002.

2. Blitz MJ, SR Ghorayeb, SL Pachtman, M Murphy, Z Rahman, L Prasannan, CP Sison, N Vohra, and BL Rochelson. “Quantitative ultrasound analysis of proximal and distal cervical tissue echogenicity in premature cervical remodeling,” Journal of Ultrasound in Medicine, Vol. 37, No. 12, pp. 2873–2879, April 2018. DOI: https://doi.org/ 10.1002/jum.14647 3. Pachtman S, SR Ghorayeb, M Blitz, K Harris, N Vohra, C Sison, and BL Rochelson. “Ultrasonic assessment of cervical heterogeneity for prediction of spontaneous preterm birth: a feasibility study,” American Journal of Perinatology, Vol. 35, No. 3, pp. 292–297, February 2018. DOI: https://www.thieme-connect.de/DOI/DOI?10.1055/s-0037-1607286 4. Ghorayeb SR, L Bracero, MJ Blitz, Z Rahman, and ML Lesser. “Quantitative ultrasound texture analysis to differentiate preterm from term fetal lungs,” Journal of Ultrasound in Medicine, Vol. 36, No. 7, pp. 1437–1443, July 2017. DOI: 10.7863/ultra.16.06069.

5. Samson P, C Hartman, R Palmerola, Z Rahman, M Siev, LS Palmer, and SR Ghorayeb.

“Ultrasonographic Assessment of Testicular Viability Using Heterogeneity Levels in Torsed Testicles,” The Journal of Urology, Vol. 197, Issue 3, Part 2, pp. 925–930, March 2017. DOI: http://dx.doi.org/10.1016/j.juro.2016.09.112 6. Patel US, SR Ghorayeb, Y Yamashita, F Atanda, AD Walmsley, and BA Scheven. “Ultrasound Field Characterization and Bioeffects in Multiwell Culture Plates,” Journal of Therapeutic Ultrasound, Vol. 3, Issue 8, June 2015. DOI: 10.1186/s40349-015-0028-5. URL: http://www.jtultrasound.com/content/pdf/s40349-015-0028-5.pdf 7. Ghorayeb SR, A Levin, M Ast, JA Schwartz, and DA Grande. “Sonographic Evaluation of Knee Cartilage Defects Implanted with Preconditioned Scaffolds,” Journal of Ultrasound in Medicine, Vol. 33, No. 7, pp. 1241–1253, July 2014.

8. Continuing Medical Examination (CME) test questions based on the article by Ghorayeb et al. “Sonographic Evaluation of Knee Cartilage Defects Implanted with Preconditioned Scaffolds,” Journal of Ultrasound in Medicine, Vol. 33, No. 7, pp. 1254–1255, July 2014.

9. Ghorayeb SR, US Patel, AD Walmsley, and BA Scheven. “Biophysical Characterization of LowFrequency Ultrasound Interaction with Dental Pulp Stem Cells,” Journal of Therapeutic

Ultrasound, Vol. 1, Issue 12, August 2013. DOI: 10.1186/2050-5736-1-12. URL: http://www.jtultrasound.com/content/1/1/12 10. Ghorayeb SR, P Petrakis, M McGrath, and BA Scheven. “Measurement of Ultrasonic Phase and Group Velocities in Human Dental Hard Tissue,” Journal of Therapeutic Ultrasound, Vol. 1, Issue 5, May 2013. DOI: 10.1186/2050-5736-1-5. URL: http://www.jtultrasound.com/content/1/1/5 11. Ghorayeb SR, and DM Rooney, “Ultrasonic Evaluation of Bone Quality in Cadaver Ilia,” Annals of Biomedical Engineering, Vol. 41, Issue 5, pp. 939-951, January 2013.

12. Ghorayeb SR, NV Shah, F Edobor-Osula, LB Lane, P Razzano, N Chahine, and DA Grande, “Ultrasonic Assessment of Extracellular Matrix Content in Healing Achilles Tendon,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control. Vol. 59, No. 4, pp. 694702, April 2012.

13. Bertoncini CA, MK Hinders, and SR Ghorayeb. “Ultrasonographic Detection of Tooth Flaws,” American Inst. Of Physics, Review of Progress in Quantitative Nondestructive Evaluation, Vol. 1211, pp. 1559-1565, Feb 2010.

14. Ghorayeb SR, CA Bertoncini and MK Hinders. “Ultrasonography in Dentistry,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 55, No. 6, pp. 12561266, June 2008.

15. Ghorayeb SR and T Valle. “Experimental Evaluation of Human Teeth Using Noninvasive Ultrasound: Echodentography,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 49, No. 10, pp. 1437-1143, October 2002.

16. Ghorayeb SR and T Valle. Front Cover Image titled “B-Scan Image of a Human Tooth,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 49, No. 10, October 2002. http://www.ieee-uffc.org/main/publications/tr/covers/49uffc10/t02acov.pdf 17. Ghorayeb SR, E Maione, and V LaMagna. “Modeling of Ultrasonic Wave Propagation in Teeth Using PSpice: A Comparison with Finite Element Models,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 48, No. 4, pp. 1124-1131, July 2001.

18. Ghorayeb SR, T Xue and W Lord. “A Finite Element Study of Ultrasonic Wave Propagation in a Tooth Phantom,” Journal of Dental Research, Vol. 77, No. 1, pp. 39-49, January 1998.

19. Yamano M and SR Ghorayeb. “A New Approach to Ultrasonic Image Reconstruction,” Nondestructive Characterization of Materials VII, Materials Science Forum, vol. 213, pp.

855-862, 1995.

20. Ghorayeb SR, W Lord and S Udpa. “Application of a Beamforming Technique to Ultrasound Imaging in Nondestructive Testing,” IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 41, No. 2, pp. 199-208, March 1994.

21. Lord W, Z You, A Safaei-nili, and SR Ghorayeb. “Finite Element Applications in NDE Engineering,” Ultrasonics International, pp. 1-4, July 1991.

Refereed Conference Papers 1. Reifsnyder JE, SR Ghorayeb, S Glykos, PK Mistry, and LS Palmer, “Quantitative Characterization of Renal Parenchymal Scarring on Ultrasound,” submitted to the Societies for Pediatric Urology Fall Congress, Scottsdale, AZ, Sep 26 – 29, 2019.

2. Sales M, D Haddad, and SR Ghorayeb, “Noninvasive Assessment of Breast Masses through Quantitative Analysis of B-scan Images of Fibroadenoma and Malignant Invasive Ductal Carcinoma Cases,” 2019 BMES Annual Meeting, Philadelphia, PA, Oct 16 – 19, 2019.

3. Glykos S, J Reifsnyder, M Mitchell, L Palmer, and SR Ghorayeb, “Quantitative Characterization of Cortex Tissue in Sonograms of Kidneys Inflicted with Vesicoureteral Reflux (VUR),” 2019 BMES Annual Meeting, Philadelphia, PA, Oct 16 – 19, 2019.

4. Zaferiou S, A Tubbs, J Shah, N Merna, and SR Ghorayeb, “Low-Frequency (LoFU) Decellularization of Cardiac Tissue,” 2019 BMES Annual Meeting, Philadelphia, PA, Oct 16 – 19, 2019.

5. Peng T, N Merna, and SR Ghorayeb, “Comparison Between Enzymatic and High-intensity Lowfrequency Ultrasound for the Isolation of Adipose-derived Mesenchymal Stromal Cell Fraction,” 2019 BMES Annual Meeting, Philadelphia, PA, Oct 16 – 19, 2019.

6. Peguero-Rosario WB, and SR Ghorayeb, “Ultrasonic Assessment of Trabecular Bone in the Femoral Head Using Finite Element Modeling,” 2019 BMES Annual Meeting, Philadelphia, PA, Oct 16 – 19, 2019.

7. Blitz MJ, SR Ghorayeb, R Yarmush, S Glykos, A Jauhari, B Rochelson, and LA Bracero, “Fetal lung echotexture in pregnancies at risk for pulmonary hypoplasia,” American Institute of Ultrasound in Medicine 2019 Convention, Orlando, FL, April 6 – 10, 2019.

8. Blitz MJ, SR Ghorayeb, LR Gainey, S Glykos, N Benja-Athonsirikul, L Prasannan, K Aibel, and B Rochelson, “Is there an association between first and second-trimester placental echogenicity and early-onset fetal growth restriction?” American Institute of Ultrasound in Medicine 2019 Convention, Orlando, FL, April 6 – 10, 2019.

9. Wu WJ, BA Morganstern, M Blitz, L Prasannan, LS Palmer, and SR Ghorayeb, “Normal Prenatal Renal Heterogeneity and Echogenicity: A Novel Sonographic Assessment,” American Institute of Ultrasound in Medicine 2019 Convention, Orlando, FL, April 6 – 10, 2019.

10. Zaferiou S, A Tubbs, C Lim, R Toncich, N Merna, and SR Ghorayeb, “Ultrasonic Characterization of the Extracellular Matrix in Cardiac Tissue,” 2018 BMES Annual Meeting, Atlanta, GA, Oct 17 – 20, 2018.

11. Lim C, R Toncich, M Murphy, and SR Ghorayeb, “Ultrasonic Assessment of Lingual Tissue Containing an Abnormal Mass,” 2018 BMES Annual Meeting, Atlanta, GA, Oct 17 – 20, 2018.

12. Redzematovic M, R Young, M Murphy, S Hogg, DM Rooney, and SR Ghorayeb, “Ultrasonic Characterization of Osteoporosis in a Bovine Femoral Head,” 2018 BMES Annual Meeting, Atlanta, GA, Oct 17 – 20, 2018.

13. KEYNOTE ADDRESS: Ghorayeb SR, B Morganstern, Wu WJ, P Casado, M Murphy, and LS Palmer, “Quantitative Assessment of Renal Heterogeneity and Echogenicity in Healthy Pediatric Patients Using a Novel Protocol,” 18th International Conference on Pediatrics Health, Madrid, Spain, August 6 – 7, 2018.

14. Morganstern B, D Kee, W Wu, J Reifsynder, P Casado, M Murphy, SR Ghorayeb, LS Palmer and C Sethna. “Detecting Pediatric Hypertension by Quantifying Renal Heterogeneity with Ultrasonography,” The Journal of Urology, 2018 American Urological Association Annual Meeting, San Fransisco, CA, May 18 – 21, 2018.

15. Blitz MJ, SR Ghorayeb, P Lakha, M Murphy, S Pachtman, C Pessel and B Rochelson.

“Association of longitudinal changes in cervical tissue echotexture and ultrasound-indicated cerclage placement,” 2018 American Institute of Ultrasound in Medicine Annual Convention, New York, NY, March 24 – 28, 2018.

16. Ghorayeb SR, MJ Blitz, S Pachtman, M Murphy, Z Rahman, and B Rochelson. “A Novel Paradigm to Predict Spontaneous Preterm Birth Using the Cervical Heterogeneity Index in Ultrasound Images,” Biomedical Engineering Society 2017 Annual Meeting, Phoenix, AZ, October 11 – 14, 2017.

17. Wu WJ, B Morganstern, V Vasudevan, A Myers, M Elmasri, M Murphy, LS Palmer, and SR Ghorayeb, “A Novel Analysis to Establish Renal Heterogeneity and Echogenicity Norms in a Healthy Pediatric Population,” Society for Pediatric Urology 2017 Fall Congress, Montreal, Canada, September 8 – 10, 2017.

18. Morganstern B, W Wu, V Vasudevan, M Elmasri, M Murphy, SR Ghorayeb, and LS Palmer, “Ureteropelvic Junction Obstruction Affects the Contralateral Kidney: A Novel Investigation

of Sonographic Heterogeneity,” Society for Pediatric Urology 2017 Fall Congress, Montreal, Canada, September 8 – 10, 2017. Won Second Place Clinical Prize Award.

19. Morganstern B, V Vasudevan, M Jurewicz, M Elmasri, W Wu, M Murphy, B Gilbert, LS Palmer, and SR Ghorayeb, “Novel Assessment of Adolescent Testicular Sonographic Heterogeneity: An Analysis of Normal Variation, Comparison of Matched Adolescent Varicocele Populations and Adult Infertility Patients,” Society for Pediatric Urology 2017 Fall Congress, Montreal, Canada, September 8 – 10, 2017.

20. Blitz MJ, SR Ghorayeb, P Casado Lopez, Z Rahman, L Prasannan, and B Rochelson, “Association of placental echogenicity at routine second-trimester ultrasound survey and early-onset fetal growth restriction,” The Human Placenta Project Conference, National Institutes of Health, Bethesda, MD, July 24 – 25, 2017.

21. Morganstern B, S Derisavifard, M Elmasri, M Murphy, B Rapkin, LS Palmer, and SR Ghorayeb, “Novel Sonographic Evaluation of Adolescent Varicoceles,” The Journal of Urology, 2017 American Urological Association Annual Meeting, Volume 197, Issue 4, Supplement, pp. e866–e867, Boston, MA, May 12 – 16, 2017.

22. Morganstern BA, W Wu, M Elmasri, M Murphy, S Mehta, SR Ghorayeb, and LS Palmer, “A New Paradigm for Assessing Renal Obstruction Pre and Post Pyeloplasty,” Society of Pediatric Urology, 65th Annual Meeting, Volume 197, Issue 4, Supplement, p1-1376, Boston, MA, May 12 – 14, 2017.

23. Blitz MJ, SR Ghorayeb, SL Pachtman, M Murphy, Z Rahman, L Prasannan, CP Sison, N Vohra, and B Rochelson, “Quantitative ultrasound analysis of proximal and distal cervical tissue echotexture in premature cervical remodeling,” The New York Perinatal Society 40th Annual Scientific Meeting, New York, NY, April 25, 2017. Won First Place Poster Award.

24. Pachtman S, SR Ghorayeb, M Blitz, K Harris, N Vohra, C Sison, Y Yamashita, and B Rochelson, “Ultrasonic assessment of cervical heterogeneity for prediction of spontaneous preterm birth,” Society of Maternal Fetal Medicine 37th Annual Scientific Meeting – The Pregnancy Meeting 2017, American Journal of Obstetrics and Gynecology. Supplement, Vol. 216, pS13, Las Vegas, NV, January 23 – 28, 2017. DOI: 10.1016/j.ajog.2016.11.909 25. Morganstern BA, W Wu, LS Palmer, and SR Ghorayeb, “Assessment of Renal Tissue Heterogeneity Levels Pre and Post Pyeloplasty: A Novel Sonographic Measurement of Obstruction,” Society for Pediatric Urology 2016 Fall Congress, Dallas, TX, September 9 – 11, 2016.

26. Ghorayeb SR, Z Rahman, and L Bracero, “Ultrasonic Texture Analysis in Preterm and Term Fetal Lungs,” Proceedings of the 3rd International Conference on Biomedical Engineering and Systems, Budapest, Hungary, August 16 – 17, 2016. Won First Place Presentation Award.

27. Hartman C, P Samson, R Palmerola, Z Rahman, M Morris, M Siev, LS Palmer, and SR Ghorayeb. “Heterogeneity on Testicular Ultrasound Differs Between Normal and Torsed in Pediatric Patients,” The Journal of Urology, 2016 American Urological Association Annual Meeting, Vol. 195, Issue 4, Supplement, pp. e583–e584, April 2016.

DOI: http://dx.doi.org/10.1016/j.juro.2016.02.222 28. Ghorayeb SR, Hartman C, P Samson, Y Yamashita, and LS Palmer. “Ultrasonic Evaluation of Heterogeneity Levels in Normal and Torsed Testes,” Proceedings of the 2nd International Conference on Biomedical Engineering and Systems, Barcelona, Spain, July 13-14, 2015.

Won First Place Presentation Award.

29. Yamashita Y, F Atanda, A Herati, G Richards, O Yaskiv, B Gilbert, and SR Ghorayeb. “An Enhanced Ultrasound Technique for Functional Evaluation of Testicular Function,” 2015 American Institute of Ultrasound in Medicine Annual Convention, Lake Buena Vista, FL, March 21-25, 2015.

30. Yamashita Y, A Herati, G Richards, O Yaskiv, SR Ghorayeb, and B Gilbert. “An Enhanced Ultrasound Technique for Functional Evaluation of Spermatogenesis,” The Journal of Urology, 2015 American Urological Association Annual Meeting, Vol. 193, Issue 4, Supplement, p. e627, April 2015.

DOI: http://dx.doi.org/10.1016/j.juro.2015.02.1757 31. Kincaid BG, F Edobor-Osula, LB Lane, NV Shah, P Razzano, NO Chahine, SR Ghorayeb, and DA Grande. “Correlation of Achilles Tendon Healing with Ultrasound Imaging and Biomechanics,” 66th Annual Meeting of the American Society for the Surgery of the Hand, Las Vegas, NV, September 8-10, 2011.

32. Ghorayeb SR, L Lozada, P Razzano, and D Grande. “Ultrasonic Assessment of Healing Tendons,” 2011 American Institute of Ultrasound in Medicine Annual Convention, New York, NY, April 14-17, 2011.

33. Edobor-Osula F, LB Lane, P Razzano, NO Chahine, NV Shah, SR Ghorayeb, and D. A. Grande.

“Correlation of Achilles Tendon Healing with Ultrasound Imaging and Biomechanics,” American Academy of Orthopaedic Surgeons Conference, San Diego, CA, February 15-19, 2011.

34. Ghorayeb SR, T Awad, P Razzano, and D Grande. “Ultrasonic Noninvasive Evaluation of Preconditioned Scaffolds in Articular Cartilage,” 2010 International Cartilage Research Society Conference, Barcelona-Sitges, Spain, September 24-29, 2010.

35. Ghorayeb SR, T Awad, P Razzano, and D Grande. “Ultrasonic Assessment of Preconditioned Scaffolds in Articular Cartilage,” 2010 American Institute of Ultrasound in Medicine Annual Convention, San Diego, CA, March 24-27, 2010.

36. Awad T, AS Levin, M Kessler, P Razzano, DA Grande, and SR Ghorayeb. “Use of Ultrasound to Evaluate Changes over Time of Bovine Chondrocytes placed within a Collagen Matrix,” Proceedings of the 2009 - 8th World Congress of the International Cartilage Research Society, Miami, Florida, May 23 – 26, 2009.

37. Ghorayeb SR. “Can Utrasound be Used for the Assessment of Bone Quality?” 2009 American Institute of Ultrasound in Medicine Annual Convention, New York, NY, April 2-5, 2009.

38. Awad T, AS Levin, M Kessler, L Dagly, P Razzano, DA Grande, and SR Ghorayeb. “Detection of Preconditioned Scaffolds in Articular Defects Using High Frequency Ultrasound,” Feinstein Institute for Medical Research Conference, Manhassett, NY, Sept. 14, 2009.

39. Ghorayeb SR. “A Novel Approach to the Assessment of Bone Quality: Ultrasonic Imaging of Bone Porosity,” 7th European Congress on Clinical and Economic Aspects of Osteoporosis and Osteoarthritis held in Porto, Portugal, March 28-31, 2007.

40. Ghorayeb SR, C Wagner, S Talwar and N Solounias. “Ultrasonic Imaging of Osteoporosis: A Novel Approach to the Assessment of Bone Quality,” IOF World Congress on Osteoporosis held in Toronto, Canada, pp. 176-177, June 2-6, 2006.

41. Ghorayeb SR, C Wagner, S Talwar and J Aloia. “Ultrasonic Imaging of Osteoporosis,” American Society for Bone and Mineral Research 27th Annual Meeting, Nashville, Tennessee, USA, September 23-27, 2005.

42. Ghorayeb SR, P Petrakis and M McGrath. “Experimental Determination of Ultrasonic Phase Velocities in Human Teeth Along Arbitrary Symmetry Directions,” IEEE Engineering in Medicine and Biology Society 25th Annual International Conf., pp. 2382-2385, September 2003.

43. Ghorayeb S R and E Maione. “Diagnostic Ultrasound for the Imaging of Teeth: A Comparison Between Experimental Results and Simulation Models,” 2000 IEEE International Ultrasonics Symposium held in San Juan, Puerto Rico, October 22-25, 2000.

44. Ghorayeb SR. “Finite Element Modeling of Ultrasonic Waves Propagation in Femoral Bones for Early Detection of Osteoporosis,” Proceedings of the Biomechanics ’98 Conference held in Beirut, Lebanon, July 7 – 14, 1998.

45. Ghorayeb SR, RA Jensen and RE Stuhler, “Ultrasonic Testing of Wooden Utility Poles,” Proceedings of the ASNT Fall 1997 Conference held in Pittsburgh, PA, October 20-24, 1997.

46. Ghorayeb SR, T Xue and W Lord. “Ultrasonic Imaging of Teeth for Early Detection of Abscesses,” 1997 IEEE International Ultrasonics Symposium held in Toronto, Ontario, October 5-8, 1997.

47. Ghorayeb SR, T Xue and W Lord. “Ultrasonic Wave Propagation in a Tooth Phantom,” Proceedings of the 24th Annual Review of Progress in QNDE conference held in San Diego, CA, July 27-August 1, 1997.

48. Ghorayeb SR and C Jennings. “A Non-Intrusive Pressure Sensor Using Inverse Magnetostriction,” Proceedings of the American Society for Nondestructive Testing Fall Conference, Dallas, TX, October 16-20, 1995.

49. Ghorayeb SR, T Hansen and FK Straub. “The Application of Magnetostrictive Smart Materials in Rotor Servoflap Control,” Proceedings of SPIE’s Smart Structures and Integrated Systems, San Diego, CA, vol. 2443, pp. 28-37, February 26 - March 3, 1995.

50. Hansen T and SR Ghorayeb. “Ultrasonic Applications Using Magnetostrictive Smart Materials,” Materials Research Society Bulletin, November 1994.

51. Ghorayeb SR and MT Lusk. “Implementation of the CLEAN Algorithm to Microwave Images in Nondestructive Testing,” Proceedings of SPIE's Advanced Microwave and Millimeter-Wave Detectors, San Diego, CA, vol. 2275, pp. 94-102, July 24-29, 1994.

52. Ghorayeb SR, W Lord and S Udpa. “The Prediction of Ultrasonic Signals Using the Data Independent Beamformer,” Proceedings of the ASNT, Spring Conference, New Orleans, LA, pp. 111-114, March 21-25, 1994.

53. Ghorayeb SR, W Lord and T Xue. “The Study of Ultrasonic Wave Propagation in a Tooth Phantom,” Proceedings of the American Society for Nondestructive Testing, Spring Conference, New Orleans, LA, pp. 27-30, March 21-25, 1994.

54. Ghorayeb SR, M Yamano, Z You and W Lord. “Ultrasonic SAFT Reconstruction Using the Finite Element Modeling Technique,” Proceedings of the 18th Annual Review of Progress in Quantitative Nondestructive Evaluation, Brunswick, ME, vol. 11B, pp. 2185-2191, July 1991.

55. Lord W, D Hsu and SR Ghorayeb, A Minachi and Z You. “Finite Element Applications in NDE Engineering,” Proceedings of the 18th Annual Review of Progress in QNDE, Brunswick, ME, vol. 11A, pp. 463-466, July 1991.

56. Hughes MS, DK Hsu, F Margetan, RB Thompson, SR Ghorayeb, DK Holger, LW Zachary and DO Thompson. “Application of SAFT on Composites,” Proceedings of the 18th Annual Review of Progress in QNDE, Brunswick, ME, vol. 11B, pp. 1413-1419, July 1991.

57. Ghorayeb SR, MS Hughes, DK Holger and LW Zachary. “A Preliminary Application of SAFT on Composites,” Proceedings of the 17th Annual Review of Progress in Quantitative Nondestructive Evaluation, La Jolla, CA, vol. 10A, pp. 1027-1034, July 1990.

58. Ghorayeb SR. “Determining the Optimal Convolution Function for Creating the Least Corrupted Uniformly Spaced Data from Noisy Nonuniformly Spaced Data According to Wiener Filter Theory,� Proceedings of the 168th Meeting of the American Astronomical Society, Ames, IA, vol. 18, p. 700, June 1986.