RESPONSES OF SHEEP TO ZYGADENUS GRAMINEUS, "DEATH CAMAS"

An extract of Zygadenus gramineus, "death camas," from which most of the resins had been removed was given intravenously to sheep prepared for recording blood-pressure and respiratory movements. Following the intravenous injection of this extract there occurred a respiratory inhibition which in the case of the injection of larger amounts of the extract was followed by asphyxia-like rises of blood-pressure. The graphic record of this asphyxial condition was practically duplicated by closing the tracheal cannula for a short time following the recovery of the animal from the effects of the plant extract. Although, from a field standpoint, no satisfactory antidote has been found, it has been demonstrated that caffein sodio-benzoate possesses marked powers of stimulation for the respiratory center affected by the depressive substances found in Zygadenus gramineus.     

Zooming in on a quantitative trait for tomato yield using interspecific introgressions

To explore natural biodiversity we developed and examined introgression lines (ILs) containing chromosome segments of wild species (Solanum pennellii) in the background of the cultivated tomato (S. lycopersicum). We identified Brix9-2-5, which is a S. pennellii quantitative trait locus (QTL) that increases sugar yield of tomatoes and was mapped within a flower- and fruit-specific invertase (LIN5). QTL analysis representing five different tomato species delimited the functional polymorphism of Brix9-2-5 to an amino acid near the catalytic site of the invertase crystal, affecting enzyme kinetics and fruit sink strength. These results underline the power of diverse ILs for high-resolution perspectives on complex phenotypes.     

Turbulent jets and eddies in the california current and inferred cross-shore transports

The instantaneous California Current is seen to consist of intense meandering current filaments (jets) intermingled with synoptic-mesoscale eddies. These quasi-geostrophic jets entrain cold, upwelled coastal waters and rapidly advect them far offshore; this behavior accounts for the elongated, cool surface features that are seen extending across the California Current region in satellite infrared imagery. The associated advective mechanism should provide significant cross-shore transports of heat, nutrients, biota, and pollutants. The dynamics of the current system should be crucially influenced by its highly variable structure.     

A theropod dinosaur embryo and the affinities of the flaming cliffs dinosaur eggs

An embryonic skeleton of a nonavian theropod dinosaur was found preserved in an egg from Upper Cretaceous rocks in the Gobi Desert of Mongolia. Cranial features identify the embryo as a member of Oviraptoridae. Two embryo-sized skulls of dromaeosaurids, similar to that of Velociraptor, were also recovered in the nest. The eggshell microstructure is similar to that of ratite birds and is of a type common in the Djadokhta Formation at the Flaming Cliffs (Bayn Dzak). Discovery of a nest of such eggs at the Flaming Cliffs in 1923, beneath the Oviraptor philoceratops holotype, suggests that this dinosaur may have been a brooding adult.     

Skeleton of the Oldest Known Pinniped, Enaliarctos mealsi

A nearly complete skeleton of the archaic pinniped Enaliarctos, found in late Oligocene or early Miocene rocks (approximately 23 million years old) of California, provides new evidence on the origin of pinnipeds. Enaliarctos retains many primitive features expected in the hypothesized common ancestor of pinnipeds. Skeletal modifications seen in Enaliarctos document swimming adaptations and indicate that pinnipeds primitively used the axial skeleton and both fore and hindflippers as sources of propulsion. Elongate hindlimbs with prominent bony processes (reflecting powerful musculature) suggest that Enaliarctos was more active on land than modern pinnipeds.