Geochemical characterization methods are commonly used in the reconstruction of prehistoric raw material use and procurement systems. Trace element studies of lithic source material and artifacts, specifically those made of obsidian, can reveal important information about the environmental and cultural factors which influence the prehistoric distribution of raw material. The...
Plasma vitamin B₁₂ concentrations of 16 elderly women were
measured using the growth response of the microorganism, Ochromonas
malhamensis. The method required major modifications which
are described in detail. All women had plasma concentrations of
vitamin B₁₂ above the normal minimum of 200 pg/ml despite the fact
that the diets...
The multistage model of carcinogenesis states that an accumulation of mutations in genes that are important for maintaining cellular homeostasis may lead to cancer. A specific type of mutation observed in particular types of cancer is the CC-->TT mutation found in the TP53 gene of patients with basal or squamous...
This investigation is a study of how the magnitude
and energy distribution of the photoelectric current from
the light emergent side of thin silver films varies with
film thickness. The Fowler-Dubridge graphical analysis
of the energy distribution of photoelectrons is used to
determine the energy of the most energetic of...
Graphium sp., a eukaryotic alkanotroph, is able to oxidize small-molecular weight gaseous n-alkanes, diethyl ether and the branched ether, methyl tert butyl ether
(MTBE). However, information regarding the biochemistry of fungal-mediated alkane and ether metabolism is limited, and questions regarding the identity of alkane oxidation catalysts and the genetic underpinnings...
The cabbage flea beetle, Phyllotreta cruciferae (Coleoptera:
Chrysomelidae) was introduced into the United States from Europe
during the 1920's and 1930's. It was described as a new species,
P. columbiana, native to North America by F. H. Chittenden in 1927.
This synonymic situation was discovered in 1953 after P. cruciferae...