Stephen J Smith Stephen J Smith Stephen J Smith is a Senior Investigator at the Allen Institute for Brain Science. Previously, Dr. Smith was Professor of Molecular and Cellular Physiology at the Stanford University School of Medicine. In 1990, Smith published an article in the journal "Science", which proposed that certain glial cells in the human brain known as astrocytes would be able to communicate through chemical signals, rather than electrical. By utilizing the neurotransmitter glutamate, he was able to show that these cells, which had once been perceived as inert tissue between neurons, in fact were actively communicating with the rest of
Process tomography imaging methods are used in process tomography, e.g. ultrasonic imaging, positron emission tomography (PET), electrical resistance tomography (ERT) and electrical impedance tomography (EIT), electrical capacitance tomography (ECT), magnetic induction tomography (MIT). In all cases external sensors are used to detect signals from boundary of the object, and the three-dimensional material distribution or the velocity field is computed using the measured data. Process tomography is an area of rapid growth both in terms of research and applications. There are number of challenges remaining in this area including data processing an image reconstruction, and application of imaging modalities in a real applications.