Modification probe design

The authors would like to acknowledge the advice of Dr. D. Torchia (National Institute of Health) who made the details of his probe design and spectrometer modification available to us. The authors would also like to acknowledge the expert advice of Don Horne in many of the electronic aspects of the spectrometer modification. 

In almost sixty years, since the first development by H. Doll, research on various aspects of induction well-logging has been carried out around the world, and there have been some rather significant advances in theory, interpretation, probe design and equipment. Moreover, completely new modifications of induction logging have been developed and their principles are described in our monograph. As a result of the efforts of scientists and engineers in the United States, former Soviet Union and other countries, induction welllogging has become the most powerful tool for a determination of formation conductivity in uncased wells. 

To increase the volume of ablation modifications have been made to the probe design, e.g. extending the length of the antenna (cluster needle, umbrella/ inverted umbrella-like design) or internal cooling of the needle to avoid premature carbonization around the probe followed by insulation and energy decay (Fig. 2.1.3). At present, the available electrodes provide ablation volumes with more or less spherical diameters of between 2 and 5 cm. 

For the design of the actively compensated RF pulse, experimental and numerical determination of the response function h(t) of the circuit is necessary. We should also keep in mind that modification to the circuit, such as probe timing, insertion or removal of RF filters, and so on, can alter h(t). In practice, it is convenient to measure the response y t) to a step excitation u(t) instead of that to the impulse excitation. By performing Laplace transformation to... 

Cell-internalization via receptors is the route of choice in a number of Nuclear Medicine assays. For MRI, the design of the Imaging Probe requires the attachment of one or more Gd(III)-chelates to the ligand molecule. Such structural modification may drastically affect the internalization process with respect to the mechanism occurring for the native ligand. 

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