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National Center for Physical Acoustics
University of Mississippi

Publications by Ultrasonics Group

  • C.P. Labuda CP, C.C. Church. Augmentation of HIFU-Induced Heating with Fibers in a Phantom. Ultrasound Med Biol, 37(3): 2011.
  • T.A. Bigelow, C.C. Church, K. Sandstrom, J.G. Abbott, M. Ziskin, P. Edmonds, B. Herman, K. Thomenius, T.J. Teo: Summary of Strengths, Weaknesses, and Proposed Improvements for the TI. Journal of Ultrasound in Medicine (in preparation).
  • J. B. Lonzaga, J. L. Raymond, J. Mobley, and D. Felipe Gaitan, Suppression of an acoustic mode by an elastic mode of a liquid-filled spherical shell resonator, to be submitted to Journal of the Acoustical Society of America (in press 2010).
  • J. R. Gladden, C. E. Skelton, and J. Mobley, Shear waves in viscoelastic wormlike micellar fluids, Journal of the Acoustical Society of America Express Letters (in press 2010).
  • J. Mobley, T. Vo-Dinh and V. V. Tuchin “Optical Properties of Tissue” in Biomedical Photonics Handbook, 2nd Edition. CRC Press,Boca Raton, FL (In Press 2010)
  • J. Webster, R. Raspet, J. Yu, and W. E. Prather, “Wind noise measured in probe type pressure sensors,” J. Acoust. Soc. Am. Vol. 127, No. 5 2764, May 2010.
  • J. Mobley, Simplified expressions of the subtracted Kramers–Kronig relations using the expanded forms applied to ultrasonic power-law systems, Journal of the Acoustical Society of America, Vol. 127, No. 1, pp. 166-173 (2010).
  • D.F. Gaitan, R.A. Tessiun, R.A. Hiller, J. Gutierrez, C. Scott, H. Tardif, B. Callahan, T.J. Matula, L.A. Crum, R.G. Holt, C.C. Church, J.L. Raymond: Transient cavitation in high-quality-factor resonators at high static pressures. Journal of the Acoustical Society of America 127(6), 3456-3465 (2010).
  • J. Mobley, R. A. Mack, J. R. Gladden, P. R. Mantena, Determination of power-law attenuation coefficient and dispersion spectra in multi-wall carbon nanotube composites using Kramers-Kronig relations, Journal of the Acoustical Society of America, Vol. 126, No.1, pp. 92-97 (2009).
    Also selected for inclusion in Virtual Journal of Nanoscale Science & Technology, Volume 20, No. 4 (2009). (American Institute of Physics)
  • B. Durning, J. Raymond, C.C. Church, R.O. Cleveland, E.L. Miller: HIFU lesion characterization in liver: acquisition and results, in Therapeutic Ultrasound, Proceedings of the 8th International Symposium on Therapeutic Ultrasound, E.S. Ebbini, ed. Melville, NY, USA: American Institute of Physics No. 1113, pp. 96-100 (2009).
  • T.R. Nelson, J.B. Fowlkes, J.S. Abramowicz, C.C. Church: Ultrasound Biosafety Considerations for the Practicing Sonographer/Sonologist. Journal of Ultrasound in Medicine 28(2), 139-150 (2009).
  • D. N. Stratis-Cullum, G. D. Griffin, J. Mobley, T. Vo-Dinh, Intensified biochip system using chemiluminescence for the detection of bacillus globigii spores, Analytical and Bioanalytical Chemistry, Vol. 391, No. 5, pp.1655-1660 (2008).
  • C.C. Church, E.L. Carstensen, W.L. Nyborg, P.L. Carson, L.A. Frizzell, M.R. Bailey: The Risk of Exposure to Diagnostic Ultrasound in Postnatal Subjects – Nonthermal Mechanisms. Journal of Ultrasound in Medicine 27(4), 565-592 (2008).
  • J. Mobley, Finite-bandwidth Kramers-Kronig relations for acoustic group velocity and attenuation derivative applied to microbubble suspensions Journal of the Acoustical Society of America, Vol. 121, No. 4, pp.1916-1923 (2007).
  • J. Mobley, The time-domain signature of negative acoustic group velocity in microsphere suspensions, Journal of the Acoustical Society of America, Vol. 122, No. 1, pp.EL8-EL14 (2007).
  • J. Mobley and R. E. Heithaus, Ultrasonic properties of a suspension of microspheres supporting negative group velocities, Physical Review Letters, Vol. 99, article no. 124301 (2007).
  • M.W. Miller, C.C. Church, R.K. Miller and M.J. Edwards: Fetal Thermal Dose Considerations during the Obstetrician’s Watch: Implications for the Pediatrician’s Observations. Birth Defects Research, Part C: Embryo Today: Reviews 81(3), 135-143 (2007).
  • C.C. Church: A Proposal to Clarify the Relationship Between the Thermal Index and the Corresponding Risk to the Patient. Ultrasound in Medicine and Biology 33(9), 1489-1494 (2007).
  • C.C. Church: Thermal Dose and the Probability of Adverse Effects from HIFU, in Therapeutic Ultrasound, Proceedings of the 6th International Symposium on Therapeutic Ultrasound, C.C. Coussios and G. ter Haar, eds. Melville, NY, USA: American Institute of Physics No. 911, pp. 131-137 (2007).
  • C.C. Church and W.D. O’Brien Jr.: Evaluation of the Threshold for Lung Hemorrhage by Diagnostic Ultrasound and a Proposed New Safety Index. Ultrasound in Medicine and Biology 33(5), 810-818 (2007).
  • C.C. Church and M.W. Miller: Quantification of Risk from Fetal Exposure to Diagnostic Ultrasound. Progress in Biophysics and Molecular Biology 93, 331-353 (2007).
  • X. Yang and C.C. Church: A simple viscoelastic model for soft tissues in the frequency range 5 – 20 MHz. IEEE Trans. UFFC 53(6), 1404-1411 (2006).
  • M.W. Miller, C.C. Church, C. Labuda, S. Mazza and J. Raymond: Biological and Environmental Factors Affecting Ultrasound-induced Hemolysis in vitro: 5. Temperature. Ultrasound in Medicine and Biology 32(6), 893-904 (2006).
  • C.C. Church, X. Yang: A theoretical study of gas bubble dynamics in tissue, in Innovations in Nonlinear Acoustics, Proceedings of the 17th International Symposium on Nonlinear Acoustics, A.A. Atchley, V.W. Sparrow, R.M. Keolian, eds. Melville, NY, USA: American Institute of Physics No. 838, pp. 217-224 (2006).
  • X. Yang, F.E. Barber, J.H. Morrissey, C.C. Church: The activation of tissue factor by high intensity focused ultrasound – a pathway to acoustic-biochemical hemostasis, in Therapeutic Ultrasound, Proceedings of the 5th International Society for Therapeutic Ultrasound, G.T. Clement, N.J. McDannold, K. Hynynen, eds. Melville, NY, USA: American Institute of Physics No. 829, pp. 548-552, (2006).
  • X. Yang, C.C. Church: Theoretical investigation of bubble heating in soft tissue, in Therapeutic Ultrasound, Proceedings of the 5th International Society for Therapeutic Ultrasound, G.T. Clement, N.J. McDannold, K. Hynynen, eds. Melville, NY, USA: American Institute of Physics No. 829, pp. 196-200, (2006).
  • S. Davis, J. Raymond, C.C. Church: Acute effects of high intenity focused ultrasound on blood vessels in vivo, in Therapeutic Ultrasound, Proceedings of the 5th International Society for Therapeutic Ultrasound, G.T. Clement, N.J. McDannold, K. Hynynen, eds. Melville, NY, USA: American Institute of Physics No. 829, pp. 55-58, (2006).
  • J. Mobley, K. R. Waters, and J. G. Miller, Causal determination of acoustic group velocity and frequency derivative of attenuation with finite-bandwidth Kramers-Kronig relations, Physical Review E, Vol. 72, No. 1, Article No. 016604 (2005).
  • X. Yang and C.C. Church: A model for the dynamics of gas bubbles in soft tissue. J. Acoust. Soc. Am. 118(6), 3595-3606 (2005).
  • J.A. Straub, D.E. Chickering, C.C. Church, B. Shah, T. Hanlon and H. Bernstein: Porous PLGA Microparticles: AI-700, An intravenously administered ultrasound contrast agent for use in echocardiography. J. Controlled Release 108, 21-32 (2005).
  • M.W. Miller, H.E. Miller and C.C. Church: A new perspective on hyperthermia-induced birth defects: The role of activation energy and its relation to obstetric ultrasound. J. Therm. Biol. 30(5), 400-409 (2005).
  • C.C. Church: Frequency, pulse length and the mechanical index. Acoustic Research Letters Online (ARLO) 6, 162-168 (2005).
  • X. Yang and C.C. Church: Nonlinear dynamics of gas bubbles in viscoelastic media. Acoustic Research Letters Online (ARLO) 6, 151-156 (2005).
  • K. R. Waters, J. Mobley, and J. G. Miller, Causality-imposed (Kramers-Kronig) relationships between attenuation and dispersion, IEEE Transactions of Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 52, No. 5, pp.822-833 (2005).
  • J. Mobley, B. M. Cullum, A. L. Wintenberg, S. S. Frank, R. A. Maples, D. L. Stokes, and T. Vo-Dinh, Single-board computer based control system for a portable Raman device with integrated chemicalidentification, Review of Scientific Instruments, Vol. 75, No. 6, pp.2016-2023 (2004).
  • C. Labuda, J Raymond, C.C. Church: Reciprocity calibration of hydrophones in the MHz frequency range, Proc. IEEE Ultrasonics Symposium, Montreal, PQ, Canada, pp. 1595-1597, (2004).
  • J. Mobley and T. Vo-Dinh, Photoacoustic method for the simultaneous acquisition of optical and ultrasonic spectra, Acoustics Research Letters Online, Vol. 3, No.4, pp.89-94 (2003). (http://ojps.aip.org/ARLO/)
  • J. Mobley, K. R. Waters, J. G. Miller, Finite bandwidth effects on the causal prediction of ultrasonic attenuation of the power-law form, Journal of the Acoustical Society of America, Vol. 114, No. 5, pp.2782-2790 (2003).
  • D.N. Stratis-Cullum, et al., “Spectroscopic Data of Biologically and Medically Relevant Species and Samples” in Biomedical Photonics Handbook, CRC Press, Boca Raton, FL (January 2003) .
  • D.E. Sosnovik, J.L. Januzzi, C.C. Church, J.A. Mertsch, A.L. Sears, R.C. Fetterman, R.C. Walovitch, M.H. Picard: Measurement of radial artery contrast intensity to assess cardiac microbubble behavior. Am. J. Echocardiogr. 16, 1267-1273 (2003).
  • C.C. Church: A theoretical study of acoustic cavitation produced by “positive-only” and “negative-only” pressure waves in vivo. Ultrasound Med. Biol. 29, 319-330 (2003).
  • K. R. Waters, M. S. Hughes, J. Mobley, J. G. Miller, Differential forms of the Kramers-Kronig dispersion relations, IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control, Vol. 50, No. 1, pp. 68-76 (2003).
  • D. N. Stratis-Cullum, G. D. Griffin, J. Mobley, A. A. Vass, and Tuan Vo-Dinh, A miniature biochip system for detection of aerosolized bacillus globigii spores, Analytical Chemistry, Vol. 75, No. 2, pp.275-280 (2003).
  • J. M. Song, J. Mobley, and T. Vo-Dinh, Detection of bacterial pathogen DNA using an integrated CMOS microchip system with capillary array electrophoresis, Journal of Chromatography B, Vol. 783, No.2, pp. 501-508 (2003).
  • J. M. Song, B. M. Cullum, J. Mobley, J. S. Bogard, M. Moscovitch, G. W. Phillips, and Tuan Vo-Dinh, Crossed-beam two-photon readout system for three-dimensional radiation dosimeters, Review of Scientific Instruments, Vol. 73, No. 12, pp.4214-4217 (2002).
  • J. M. Song, J. Mobley, and T. Vo-Dinh, Integrated circuit microchip system with multiplex capillary electrophoresis module for DNA analysis, Analytica Chimica Acta Vol. 466, No.2, pp. 187-192 (2002).
  • J. Mobley, K. R. Waters, M. S. Hughes, C. S. Hall, J. N. Marsh, G. H. Brandenburger, and J. G. Miller, Kramers-Kronig relations applied to finite bandwidth data from suspensions of encapsulated microbubbles, Journal of the Acoustical Society of America, Vol. 108, No. 5, Pt. 1, pp.2091-2106 (2000); 112 (2), 760–761(E) (2002).
  • C.C. Church: Spontaneous, homogeneous nucleation, inertial cavitation and the safety of diagnostic ultrasound. Ultrasound Med. Biol. 28, 1349-1364 (2002).
  • J. Yao, M. Takeuchi, C. Taupe, M. Sheahan, R. Connolly, R.C. Walovitch, R.C. Fetterman, C.C. Church, J.E. Udelson, N.G. Pandian: Evaluation of a New Ultrasound Contrast Agent (AI-700) Using 2D and 3D Imaging during Acute Ischemia. Am. J. Echocardiogr. 15, 686-694 (2002).
  • C.C. Church and E.L. Carstensen: ‘Stable’, inertial cavitation. Ultrasound Med. Biol. 27, 1435-1437 (2001).
  • Chi Z., Cullum B.M., Stokes D.L., Mobley J., Miller G.H., Hajaligol M.R., Vo-Dinh T, Laser-induced fluorescence studies of polycyclic aromatic hydrocarbons (PAH) vapors at high temperatures, Spectrochimica Acta Part A, Vol. 57, No. 7, pp. 1377-1384 (2001).
  • A. E. Finch-Johnston, H. M. Gussak, J. Mobley, M. R. Holland, O. Petrovic, J. E. Perez, and J G. Miller, Cyclic variation of integrated backscatter: Dependence of time delay on the echocardiographic view used and the myocardial segment analyzed, Journal of the American Society of Echocardiography, Vol. 13, No. 1, pp. 9-17, (2000).
  • B. M. Cullum, J. Mobley, Z. Chi, D. L. Stokes, G. H. Miller, and Tuan Vo-Dinh, Development of a compact, handheld Raman instrument with no moving parts for use in field analysis, Review of Scientific Instruments, Vol. 71, No. 4, pp.1602-1607, (2000).
  • B. M. Cullum, J. Mobley, J. S. Bogard, M. Moscovitch, G. W. Phillips, and T. Vo-Dinh, Three-dimensional optical random access memory materials for use as radiation dosimeters, Analytical Chemistry, Vol. 72, No. 22, pp.5612-5617 (2000).
  • K. R. Waters, M. S. Hughes, J. Mobley, G. H. Brandenburger, and J. G. Miller, On the applicability of Kramers-Kronig relations for media with ultrasonic attenuation obeying a frequency power law, Journal of the Acoustical Society of America, Vol. 108, No. 2, pp.556-563 (2000).
  • M.C. Moreno-Bondi, J. Mobley, J. P. Alarie, and T. Vo-Dinh, Antibody-based biosensor for breast cancer with ultrasonic regeneration, Journal of Biomedical Optics, Vol. 5, No. 3, pp.350-354 (2000).
  • A. E. Finch-Johnston, H. M. Gussak, J. Mobley, M. R. Holland, O. Petrovic, J. E. Perez, and J G. Miller, Dependence of “apparent”magnitude on the time delay of cyclic variation of myocardial backscatter, Ultrasound In Medicine and Biology, Vol. 25, No. 5, pp. 759–762, (1999).
  • J. Mobley, K. R. Waters, C. S. Hall, J. N. Marsh, M. S. Hughes, G. H. Brandenburger, and J. G. Miller, Measurements and predictions of the phase velocity and attenuation coefficient in suspensions of elastic microspheres, Journal of the Acoustical Society of America, Vol. 106, No. 2, pp.652-659 (1999).
  • C.C. Church and A.A. Brayman: Can the Presence of Contrast Media Promote Ultrasound Bioeffects?. In: Trends in Contrast Media, edited by H.S. Thomsen, R.N. Muller and R.F. Mattrey, Springer-Verlag (1999).
  • J. Mobley, J. N. Marsh, C. S. Hall, M. S. Hughes, G. H. Brandenburger, and J. G. Miller, Broadband measurements of phase velocity in Albunex suspensions, Journal of the Acoustical Society of America, Vol. 103, No. 4, pp.2145-2153 (1998).
  • C. S. Hall, J. N. Marsh, M. S. Hughes, J. Mobley, K. D. Wallace, J. G. Miller, G. H. Brandenburger, Broadband measurements of the attenuation coefficient and backscatter coefficient for suspensions: A potential calibration tool, Journal of the Acoustical Society of America, Vol. 101, No. 2, pp.1162-1171 (1997).
  • J. N. Marsh, C. S. Hall, M. S. Hughes, J. Mobley, J. G. Miller, G. H. Brandenburger, Broadband through-transmission signal loss measurements of Albunex suspensions at concentrations approaching in vivo doses, Journal of the Acoustical Society of America. Vol. 101, No. 2, pp.1155-1161 (1997).
  • J.S. Allen, R.A. Roy and C.C. Church: On the Role of Shear Viscosity in Mediating Inertial Cavitation from Short-Pulse, Megahertz-Frequency Ultrasound. IEEE Trans. UFFC 44, 743-751 (1997).
  • A.A. Brayman, C.C. Church and M.W. Miller: Re-evaluation of the concept that high cell concentrations “protect” cells in vitro from ultrasonically induced lysis. Ultrasound Med. Biol. 22, 497-514 (1996).
  • J. Mobley, C. E. Banta, H. M. Gussak, J. G. Perez, J. G. Miller, Clinical tissue characterization: Online determination of magnitude and time delay of myocardial backscatter, Video Journal of Echocardiography, Vol. 5, No. 2, pp.40-48 (1995).
  • C.C. Church: The effects of an elastic solid surface layer on the radial pulsations of gas bubbles. J. Acoust. Soc. Am. 97, 1510-1521 (1995).
  • E.L. Carstensen, P. Kelly, C.C. Church, A.A. Brayman, S.Z. Child, C.H. Raeman, L. Schery: Lysis of erythrocytes by exposure to c.w. ultrasound. Ultrasound Med. Biol. 19, 147-165 (1993).
  • K.Q. Schwarz, C.C. Church, P. Serrino and R.S. Meltzer: The “Acoustic Filter”: an ultrasonic fluid filtration system to reduce microbubble embolization during cardiopulmonary bypass. J. Am. Col. Cardiol. 104, 1647-1653 (1992).
  • A.R. Kolaini, C.C. Church, R.A. Roy, L.A. Crum: The acoustic emissions from bubble plumes generated by an impacting transient water jet, in Proceedings of the 14th ICA, Beijing (September, 1992).
  • C.C. Church: The effects of surface layers of viscoelastic materials on the radial pulsations of gas bubbles, in Proceedings of the 14th International Congress on Acoustics (ICA), Beijing (September, 1992).
  • D.F. Gaitan, L.A. Crum, C.C. Church, R.A. Roy: Sonoluminescence and bubble dynamics for a single, stable, cavitation bubble. J. Acoust. Soc. Am. 91, 3166-3183 (1992).
  • L.A. Crum, R.A. Roy, M.A. Dinno, C.C. Church, R.E. Apfel, C.K. Holland and S.I. Madanshetty: Acoustic cavitation produced by microsecond pulses of ultrasound: A discussion of some selected results. J. Acoust. Soc. Am. 91, 1113-1119 (1992).
  • R.A. Roy, C.C. Church and A. Calabrese: Cavitation produced by short pulses of ultrasound, in Frontiers of Nonlinear Acoustics: Proceedings of 12th ISNA, edited by M.F. Hamilton and D.T. Blackstock, Elsevier, London, pp. 476-481 (1990).
  • C.C. Church and L.A. Crum: A theoretical study of cavitation generated by four commercially available extracorporeal shock wave lithotripters, in Frontiers of Nonlinear Acoustics: Proceedings of 12th ISNA, edited by M.F. Hamilton and D.T. Blackstock, Elsevier, London, pp. 433-438 (1990).
  • Y. Doida, M.W. Miller, C. Cox and C.C. Church: Confirmation of an ultrasound-induced mutation in two in vitro mammalian cell lines. Ultrasound Med. Biol. 16, 699-705 (1990).
  • M. Inoue, M.W. Miller and C.C. Church: An alternative explanation for a postulated nonthermal, noncavitational ultrasound mechanism of action on in vitro cells at hyperthermic temperature. Ultrasonics 28, 185-189 (1990).
  • M.W. Miller, C.C. Church and V. Ciaravino: Time lapse and microscopic examinations of insonated in vitro cells. Ultrasound in Med. and Biol. 16, 73-79 (1990).
  • M. Inoue, C.C. Church, A. Brayman, M.W. Miller and M.S. Malcuit: Confirmation of the protective effect of cysteamine in in-vivo ultrasound exposures. Ultrasonics 27, 362-369 (1989).
  • C.C. Church and L.A. Crum: Acoustic cavitation and extracorporeal shock wave lithotripsy, Proceedings of the 13th ICA, Belgrade, Vol. 4, 205-208 (1989).
  • M.W. Miller, M. Azadniv, S.E. Pettit, C.C. Church, E.L. Carstensen, and D. Hoffman: Sister chromatid exchanges in Chinese hamster ovary cells exposed to high intensity pulsed ultrasound: inability to confirm previous findings. Ultrasound in Med. and Biol., 15, 225-262 (1989).
  • E.J. Aymé-Bellegarda and C.C. Church: Nonmonotonic behavior of the maximum collapse pressure in a cavitation bubble. IEEE Trans. UFFC 36, 561-564 (1989).
  • C.C. Church: A theoretical study of cavitation generated by an extracorporeal shock wave lithotripter. J. Acoust. Soc. Am. 86 215-227 (1989).
  • M.W. Miller, C.C. Church, A.A. Brayman, M.S. Malcuit, and R.W. Boyd: An explanation for the decrease in cell lysis in a rotating tube with increasing ultrasound intensity. Ultrasound in Med. and Biol. 15, 67-72, (1989).
  • C.C. Church: A method to account for acoustic streaming when predicting bubble growth rates produced by rectified diffusion. J. Acoust. Soc. Am. 84, 1758-1764, (1988).
  • M.W. Miller, C.C. Church and C. Cox: Lack of effect of continuous wave ultrasound exposure on in vivo Chinese hamster cheek pouch epithelial mitotic index. Ultrasonics 26 (5), 277-279, (1988).
  • H.G. Flynn and C.C. Church: Transient pulsations of small gas bubbles in water. J. Acoust. Soc. Am. 84, 985-998, (1988).
  • C.C. Church: Prediction of rectified diffusion during nonlinear bubble pulsations at biomedical frequencies. J. Acoust. Soc. Am. 83, 2210-2218, (1988).
  • M.W. Miller, C.C. Church and S.B. Barnett: Bioeffects of Doppler ultrasound in the maternal-fetal context. Proceedings of a NIH Workshop on Doppler Ultrasound Measurement of Maternal-Fetal Hemodynamics, edited by D. Maulik and R. McNellis, Perinatology Press, 1987.
  • H.G. Flynn and C.C. Church: A mechanism for the generation of cavitation maxima by pulsed ultrasound. J. Acoust. Soc. Am. 76, 505-512, 1984.
  • C.C. Church and M.W. Miller: The kinetics and mechanics of ultrasonically-induced cell lysis produced by non-trapped bubbles in a rotating culture tube. Ultrasound in Med. and Biol. 9, 385-393, 1983.
  • C.C. Church: The physics, kinetics and mechanics of ultrasonically-induced mammalian cell lysis in the rotating tube exposure system. Ph.D. thesis. The University of Rochester, Rochester, NY, 1983.
  • C.C. Church, H.G. Flynn, M.W. Miller and P.G. Sacks: The exposure vessel as a factor in ultrasonically-induced mammalian cell lysis. II. An explanation of the need to rotate exposure tubes. Ultrasound in Med. and Biol. 8, 299-309, 1982.
  • P.G. Sacks, M.W. Miller and C.C. Church: The exposure vessel as a factor in ultrasonically-induced mammalian cell lysis. I. A comparison of tube and chamber systems. Ultrasound in Med. and Biol. 8, 289-298, 1982.

Patents:

  • K. Schwarz, R.S. Meltzer and C.C. Church: System for treating blood processed in a cardiopulmonary bypass machine and ultrasound filtration apparatus useful therein. U.S. No. 5,334,136; 1994.
  • H. Bernstein, J.S. Straub, H.T. Brush and C.C. Church: Polymer-lipid microencapsulated gases for use as imaging agents. U.S. No. 5,837,221; 1998.
  • C.C. Church, H. Bernstein, J.S. Straub and H.T. Brush: Method for enhancing the echogenicity and decreasing the attenuation of microencapsulated gases. U.S. No. 6,045,777; 2000.