The metabolism of pyrrolizidine alkaloids and other
drugs was studied with regard to nutritional status and
species differences. Pyrrolizidine alkaloids which are biotransformed
to severely toxic metabolites were isolated
from tansy ragwort (Senecio jacobaea). Semi-purified alkaloid
crystals containing five alkaloids (senecionine, seneciophylline,
jacobine, jacoline, and jacozine) were prepared
and found...
Turnip yellow mosaic virus is a monopartite, plus sense RNA virus
infecting the Cruciferae, and is a model system for the study of RNA virus
replication. A cDNA clone (pTYMC) representing an infectious RNA
genome of the European isolate of TYMV was constructed and used to assess
the importance of...
Myxobacteria represent an interesting class of Gram-negative soil bacteria. These bacteria utilize organic materials from the environment as a food source by the action of their extracellular hydrolytic enzymes. They grow vegetatively in the presence of adequate nutrients. During starvation conditions, however, they aggregate and form multicellular structures called fruiting...
The seasonal climate drivers of the carbon cycle in tropical forests remain poorly known, although these forests account for more carbon assimilation and storage than any other terrestrial ecosystem. Based on a unique combination of seasonal pan-tropical data sets from 89 experimental sites (68 include aboveground wood productivity measurements and...
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Science has a critical role to play in guiding more sustainable development trajectories. Here, we present the Sustainable Amazon Network (Rede Amazonia Sustentavel, RAS): a multidisciplinary research initiative involving more than 30 partner organizations working to assess both social and ecological dimensions of land-use sustainability in eastern Brazilian Amazonia. The...
The fermentation of honey-based musts has been a feature of civilization for millennia. Typically comprised of 75-90% (w/w) simple (i.e. fermentable) sugars, the glucose and fructose present are readily fermented by either pitched or adventitious micro-organisms. Nevertheless, despite its venerable heritage, honey-based fermentations are prone to inconsistency, and it is...
Seismic refraction data collected in 1985 by the USGS were used in
this study to derive the P and S velocity structure of the crust beneath the
Gulf of Maine. The data quality differs among instruments and is affected
by surficial lateral heterogeneities, a ringy source signature and
reverberations. Velocity...
The design and construction of two new sample injection systems or nozzles, for use with the Oregon State electron diffraction apparatus are discussed. One of these nozzles was intended for use with volatile samples the vapors of which were to be heated or cooled over the range -196 to 540°C;...
BACKGROUND: A substantial proportion of the general population has low lung function, and lung function is known to decrease as we age. Low lung function is a feature of several pulmonary disorders, such as uncontrolled asthma and chronic obstructive pulmonary disease (COPD). The objective of this study is to investigate...
Background: Pinnipeds, including many endangered and declining species, are inaccessible and
difficult to monitor for extended periods using externally attached telemetry devices that are shed
during the annual molt. Archival satellite transmitters were implanted intraperitoneally into four
rehabilitated California sea lions (Zalophus californianus) and 15 wild juvenile Steller sea lions...