Evoked potentials in artificial neural nets

A neural net model of discrete populations of formal neurons have been constructed to study evoked potentials based on our previous simulation studies (Anninos, 1972). Some interesting results came up from the examination of our findings regarding the latencies and the period of the cyclic activity of the evoked potentials. In fact, the different successive latencies for the five identical stimuli and the different periods for each of the cyclic activities, all are consequences of inhibitory and excitatory influences from a large neuronal population. Furthermore, such behavior of the system is not only related to the unknown neuronal population but was also substantially altered by what occurred in other systems at the time of stimulus, or prior to it.Computation assistance was provided by the Health Sciences Computing Facility, UCLA, sponsored by NIH Special Research Resources Grant RR-3. Research was sponsored by NSF Grant GB 30498 and NIH Grant NS-8498.     

Activated lymphocytes trigger lymphoblast extravasation.

Intraperitoneal stimulation of adoptively sensitized rats with bacterial antigen promotes the localization of lymphoblasts at the site of antigen deposition. Lymphoblast extravasation activity (LEA) is generated only when specifically immune donor lymphocytes and the recipients of these cells share at least on Ag-B haplotype. However, if the specificity criteria for its formation are satisfied, LEA promotes the local development of lymphoblasts of all available specificities and irrespective of their Ag-B genotype. Allogeneic lymphoblasts do not participate actively in the delayed inflammatory reaction even when they are passively recruited into exudates. The results suggest that LEA is a T cell-derived mediator that amplifies the delayed type hypersensitivity reaction by directing recently activated lymphocytes into lesions.     

Halobates collected during the circumnavigational expedition 'Operation Drake'

Samples of marine pleuston were collected from the sea-surface along considerable sections of the track of Eye of the Wind during its 2-year circumnavigational expedition 'Operation Drake' from November 1978 to October 1980. One hundred and eleven of the tow samples contained insects of the genus Halobates . They were assigned to four oceanic species: H. micans, H. sericeus, H. germanus and H. splendens; two coastal species: H. maculatus, H. princeps, and one undescribed species. Various development stages of the oceanic species were found. The locations, time of collection and surface temperatures where sea-skaters were collected are tabulated. Distributional boundaries and population densities of the oceanic species collected are discussed.