ABSTRACT
One of Titan's most intriguing attributes is its copious but featureless atmosphere. The Voyager 1 fly-by and occultation in 1980 provided the first radial survey of Titan's atmospheric pressure and temperature and evidence for the presence of strong zonal winds. It was realized that the motion of an atmospheric probe could be used to study the winds, which led to the inclusion of the Doppler Wind Experiment on the Huygens probe. Here we report a high resolution vertical profile of Titan's winds, with an estimated accuracy of better than 1 m s(-1). The zonal winds were prograde during most of the atmospheric descent, providing in situ confirmation of superrotation on Titan. A layer with surprisingly slow wind, where the velocity decreased to near zero, was detected at altitudes between 60 and 100 km. Generally weak winds (approximately 1 m s(-1)) were seen in the lowest 5 km of descent.
ABSTRACT
Events leading to the interest in dietary fat and immunity are summarized. This is followed by an account of the possible functions of prostaglandins and other eicosanoids in the immune response. Dietary studies on the influence of quantity and quality of fat on immune responses and the histopathology of lymphoid organs are critically reviewed. The next section deals primarily with work conducted in the authors' laboratories on essential fatty acid deficiency and the immune response and on the effects of varying the ratio of dietary linoleic to linolenic acids on prostaglandin synthesis by immunocompetent cells and immune functions. A brief account of a study on the influence of dietary fat on leukotriene synthesis follows. Finally the problems encountered in research on dietary fat and immunity are discussed and recommendations for design and execution of such studies are given.
