The Past and Future of University Research Reactors
Research nuclear reactors at U.S. universities continue to contribute materially to research of value to the nation. Despite a number of high-level studies sponsored by the federal government that expressed deep concern, their number has shrunk to less than one-half that of 30 years ago. What is now being done and what will be required to stem these losses are discussed in this [Policy Forum][1].

 [1]: http://www.sciencemag.org/cgi/content/full/295/5563/2217
On the development of electron microprobe zircon fission-track geochronology
Abstract The fission-track method has been applied for decades to quantify rates and timing of processes in the shallow crust. The most widely used approach, the external detector method, involves counting fission-tracks, a decay product resulting from the spontaneous fission of 238 U, and a paired set of induced tracks (parent proxy) from the thermal neutron irradiation of 235 U. We propose an alternate method of dating zircons that utilizes an electron microprobe to directly measure uranium concentration [U] and image the number of spontaneous fission-tracks or etch figures that intersect the surface of the crystal using an electron backscatter detector. The electron microprobe fission-track (EP-FT) method is used to date six zircon samples, four of which are widely used as standards: Fish Canyon Tuff, Peach Springs Tuff, Buluk Member of the Bakata Formation (tuff), Tardee Rhyolite, Mt. Dromedary Complex (hypabyssal granite), and Browns Park Formation (tuff). All samples yield ages that overlap within two standard deviations of published reference ages determined using other radiometric techniques (i.e., K/Ar, 40 Ar/ 39 Ar, and U/Pb) and also by the traditional fission-track external detector method. To correct for poorly constrained parameters such as the spontaneous fission decay constant, weight to volume percent conversions, etching efficiency, and selection bias, we calculate a preliminary Z proportionality factor of 4469 ± 661 (1σ). The EP-FT technique avoids the hazard and expense of thermal neutron irradiation, allows simultaneous chemical compositions to be determined, removes the step of counting an external detector manually, and will likely allow much higher track densities to be counted than would be normally possible with optical microscopy. The technique is ideal for dating moderate to high U zircons (>100 ppm U).
Accumulation of Bone-Seeking Radionuclides in Liver Metastasis from Colon Carcinoma
Fifteen colon cancer patients with metastasis to the liver were examined by both liver and bone scans. Seven of these showed accumulation of bone seeking radionuclides in the liver at the site of a defect in the scan. Such accumulation was found in two diphosphonate, in one pyrophosphate and in six 18F scans. To our knowledge, this is the first series to report localization of 18F in intrahepatic metastasis from colon cancer. The precise mechanism for this non-skeletal accumulation is unknown.