ABSTRACT
Neutrinos are elementary particles that carry no electric charge and have little mass. As they interact only weakly with other particles, they can penetrate enormous amounts of matter, and therefore have the potential to directly convey astrophysical information from the edge of the Universe and from deep inside the most cataclysmic high-energy regions. The neutrino's great penetrating power, however, also makes this particle difficult to detect. Underground detectors have observed low-energy neutrinos from the Sun and a nearby supernova, as well as neutrinos generated in the Earth's atmosphere. But the very low fluxes of high-energy neutrinos from cosmic sources can be observed only by much larger, expandable detectors in, for example, deep water or ice. Here we report the detection of upwardly propagating atmospheric neutrinos by the ice-based Antarctic muon and neutrino detector array (AMANDA). These results establish a technology with which to build a kilometre-scale neutrino observatory necessary for astrophysical observations.
ABSTRACT
Clinicult, a selective medium for culturing Neisseria gonorrhoeae, was field-tested in a gonorrhea screening program in Seattle, Wash., in 1973. The results with this medium and with the Transgrow and Thayer-Martin culture systems were compared as to sensitivity and specificity. A total of 5,141 women from three patient groups were included in the study. Group 1 consisted of 720 female patients of the venereal disease clinic of the Seattle-King County Health Department, who served as the control group. When this group was screened with the Clinicult and Thayer-Martin culture media, the Thayer-Martin medium proved superior in identifying positive carriers. Group 2 was composed of approximately 2,000 patients from five different facilities, including family planning clinics and hospital out patient services. No statistical difference in accuracy was found between the two culture systems used for this group-Clinicult and Transgrow. Group 3 was comprised of approximately 2,500 female patients who were screened with the Clinicult and Transgrow cultures by their own private physician or his staff. The Clinicult system proved significantly less effective than the Transgrow cultures in identifying infected females in group 3. The physicians varied greatly in their ability to use the Clinicult system successfully. Possible reasons for their errors may have been (a) lack of motivation and of care by their office personnel in conducting the necessary additional procedures required with Clinicult, (b) the inhibitory nature of the medium, and (c) the failure of the medium to produce colonies of adequate size. The staffs of communitywide screening programs for gonorrhea need to be highly selective in choosing the medical facilities in which to use the Clinicult culture system. When laboratory facilities are available for the full utilization of the Thayer-Martin medium, this system is preferable. When, however, standard culture procedures are not readily available, Clinicult, properly used, can reduce the central laboratory load by eliminating the need for processing negative cultures.
