Mineral resources of Alaska, report on progress of investigations in 1913; Gold lodes and placers of the Willow Creek District, Alaska. Mineral resources of the upper Matanuska and Nelchina valleys, Alaska. Preliminary report on the Broad Pass region. Mining in the Valdez Creek placer district

In the course of several 21-cm observing programmes being carried out by the Leiden Observatory with the 25-meter telescope at Dwingeloo, a fairly complete, though inhomogeneous, survey of the regionl11= 0° to 66° at low galactic latitudes is becoming available. The essential data on this survey are presented in Table 1. Oort (1967) has given a preliminary report on the first and third investigations. The third is discussed briefly by Kerr in his introductory lecture on the galactic centre region (Paper 42). Burton (1966) has published provisional results of the fifth investigation, and I have discussed the sixth in Paper 19. All of the observations listed in the table have been completed, but we plan to extend investigation 3 to a much finer grid of positions.

Preliminary Report of a Comparative Study of Seminiferous Tubular Epithelium from Rats Flown on Cosmos 1887 and SL3

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100103449 ◽

1988 ◽

Vol 46 ◽

pp. 276-277

Author(s):

Walter J. Sapp ◽

D.E. Philpott ◽

C.S. Williams ◽

K. Kato ◽

J. Stevenson ◽

...

Keyword(s):

Space Flight ◽

Physiological Response ◽

Preliminary Report ◽

Complete Recovery ◽

Environmental Constraints ◽

Tubular Epithelium ◽

Testicular Weight ◽

Testicular Morphology ◽

Normal Offspring ◽

Rats And Mice

Space flight, with its unique environmental constraints such as immobilization, decreased and increased pressures, and radiation, is known to affect testicular morphology and spermatogenesis. Selye, summarized the manifestations of physiological response to nonspecific stress and he pointed out that atrophy of the gonads always occurred. Reports of data collected from two dogs flown in space for 22 days (Cosmos 110) indicate that there was an increase of 30 to 70% atypical spermatozoa when compared to ground based controls. Seventy-five days after the flight the abnormalities had decreased to the high normal value of 30% and mating of these dogs after this period produced normal offspring, suggesting complete recovery. Effects of immobilization and increased gravity were investigated by spinning rats and mice at 2x g for 8-9 weeks. A decrease in testicular weight was noted in spun animals when compared to controls. Immobilization has been show to cause arrest of spermatogenesis in Macaca meminstrins.