Methane is a product of biogeochemical processes which respond to changes in climate. The history of atmospheric methane is recorded by ice cores providing insight into past changes in these biogeochemical processes. This dissertation is comprised of three studies which focus on centennial- and millenial-scale variability of methane from ice...
In the Willamette Valley of Oregon, a combination of the need for rotational crops and an increased desire for biofuel production created interest in planting Brassica napus (canola). However, questions were raised arisen over the potential damage canola production could have on the preexisting Brassica vegetable seed industry. To address...
The variable length, six-electrode plasma source for atomic
emission spectroscopy described here is operated from three
compact, simple, and inexpensive direct current power supplies. The
vertical arcs formed between the three electrode pairs completely
entrain the sample and are typically operated at 40 V and 20 A.
Three concentric quartz...
The principal objective of this study was to identify
and investigate the underlying basis for variations in the
volumes of exports of U.S. winter pears during the 1947 to
1974 period. A number of factors thought to be of importance
in the determination of the volume of exports of a...
New ice cores retrieved from the Taylor Glacier (Antarctica) blue ice area contain ice and air spanning the Marine Isotope Stage (MIS) 5/4 transition, a period of global cooling and ice sheet expansion. Chronologies were determined for the ice and air bubbles in the new ice cores by visually matching...
The public health and economic significance of rapid acid production
by lactic streptococci in controlled dairy fermentations is well
known. However, the fast acid-producing characteristic of these organisms
is not stable, and cultures of fast organisms have been shown
to contain slow cells. These studies were carried out to characterize...
Chemically defined liquid media were devised which supported
excellent growth of Taphrina cerasi and T. deformans. When grown
in fermentation culture vessels, T. cerasi and T. deformans released
cytokinins into the liquid media. The presence of these cell division
factors was demonstrated with the soybean tissue assay which is
specific...
The teliospore of Tilletia caries germinates to produce a promycelium
with a whorl of primary sporidia at its tip. The time between
emergence of the promycelium and the development of primary sporidia
averaged 2.3 h. Fusion between compatible sporidia occurred within
an additional 3.8 h. Primary sporidia appeared to be...