In this article the forces associated with the gradients of a radio frequency (RF) field at the boundary between fluids and cell membranes are calculated, and it is shown that they can be large enough to affect the particle motion by amounts that are on the same order of magnitude as the random diffusion motion when the energy imparted to the particles is a reasonable fraction of the thermal energy. The induced dipole moment is assumed to track the alternating RF so that the force exerted by the gradient is in a constant direction; and this in turn leads to a modification of the particle distribution, even when the energy added to the particle is very small. For RF fields of 45 V/m the energy acquired by an induced dipole moment is expected to be on the order of a micro electron volt and small compared to the average thermal energy.
|Number of pages||7|
|Publication status||Published - 2005 Feb|
Bibliographical noteFunding Information:
We gratefully acknowledge the outstanding contributions of RHYME investigators at the following sites: University of Florence, Italy, M. Maggi; University Hospital Halle, Germany, H. Behre; VU Medical Center, The Netherlands, E. Meuleman; Erasmus MC Rotterdam, Netherlands, G. Dohle; Karolinska University Hospital, Sweden, S. Arver; Manchester Royal Infirmary, UK, F. Wu; Private Practice of Urology/Andrology, Germany, H. Porst; Barnsley Hospital NHS Foundation Trust, UK, T.H. Jones; Royal Victoria Infirmary, UK, R. Quinton; Sapienza University of Rome, Italy, A. Lenzi; Royal Free Hampstead NHS, UK, PM. Bouloux; Carlos Haya University Hospital, Spain, A.M. Morales; Holly Cottage Clinic, UK, G. Hackett; Uroh?alsan i Sk?ovde, Sweden, P. Stroberg; University of Parma, Italy, M. Maggio; Hospital Virgen del Rocio, Spain, N. Cruz; Ospediali Riuniti - Ancona, Italy, G. Balercia; Segeberger Kliniken, Germany, A. Yassin; Amstelland Hospital, Netherlands, C. Reisman; Fundacio Puigvert, Spain, L. Bassa; Hesperia Hospital, Italy, E. Pescatori; Hospital Universitario Puerta de Hierro-Majadahonda, Spain, J.I. Martinez Salamanca; Hospital Universitario 12 Octubre, Spain, J. Romero Otero; Evangelisches Krankenhaus Herne, Germany, F. Jockenhoevel; Andros Mens Health Institutes, Netherlands, F. Debruyne. Valuable assistance was provided by Ms. Juli Martha, Madhavi Kamma, Blandyna Williams and other research staff at NERI. We acknowledge guidance and support from Drs. Farid Saad, Albert Radlmaier, and Andreas Mattern at Bayer Healthcare.
All Science Journal Classification (ASJC) codes
- Radiology Nuclear Medicine and imaging