that the potassium relaxation times were much shorter compared with aqueous solutions of potassium ions. This suggested that potassium was not free but complexed to 'fixed-charge' counter-ions, as he had previously determined. He and other researchers independently investigated the signals of 1H NMR in cells, and found that the relaxation times were much shorter than in distilled water. This was consistent with ordering of a large part of the water by adsorption onto macromolecular surfaces. Damadian predicted that cancerous cells would have longer relaxation times, both because of the disordering of malignant cells and because of their elevated potassium levels, since the potassium ions would be 'structure-breaking' to the ordered water fraction. In a 1971 paper in the journal Science, SUNY Downstate Medical Center professor Damadian reported that tumors can be detected in vivo by nuclear magnetic resonance (NMR) because of much longer relaxation times than normal tissue. He suggested that these differences could be used to detect cancer, even in the early stages where it would be most treatable, though later research would find that these differences, while real, are too variable for diagnostic purposes. However, Damadian in his seminal paper claimed only that his method was a detection tool, making no claim about being a diagnostic tool, but intended that it would provide a non-invasive way of detecting cancers and monitoring the effectiveness of their therapy. In 1974, he received the first patent in the field of MRI when he patented the concept of NMR for detecting cancer after filing an application in 1972. As the National Science Foundation notes, "The patent included the idea of using NMR to 'scan' the human body to locate cancerous tissue." However, it did not describe a method for generating pictures from such a scan or precisely how such a scan might be done. However, Damadian's recognition that NMR relaxation time can be used to distinguish different tissue types and malignant tissue is what gives MRI its contrast to tissue types. In the 1950s, Herman Carr reported creating a one-dimensional magnetic resonance (MR) image. Prompted by Damadian's report on the potential medical uses of NMR, Paul Lauterbur expanded on Carr's technique and developed a way to generate the first MRI images, in 2D and 3D, using gradients. Peter Mansfield from the University of Nottingham then developed a mathematical technique that would allow scans to take seconds rather than hours and produce clearer