The end of the Cold War brought about changes within international political relations that resulted in expanded interest in global civil society. Such developments, like globalization and democratization, have encouraged the growth of social and political organizations. Political scientists have found that these inter-governmental and non-governmental organizations have a significant...
Recent studies of headwater streams have demonstrated their importance to overall watershed biodiversity, nutrient cycling, and energy flux. However, little attention has been paid to long-term effects of forest harvest on macroinvertebrate communities in headwater streams. This study investigated headwater stream macroinvertebrate communities in the H.J. Andrews Experimental Forest, Oregon,...
Traditionally linear actuator applications are addressed by the use of hydraulic systems. The high maintenance cost and poor reliability will always be the most critical problem in the real applications. Benefited from both the high mechanical advantage of the roll screw and the simple structure of the switched reluctance motor,...
For the first objective of this thesis, we attempt to understand the role of water flow and directionality in determining steelhead (Oncorhynchus mykiss) and spring/summer and fall Chinook (O. tschawytscha) migration patterns within the Columbia River Estuary and plume by integrating recent advances in biotelemetry and environmental observation and forecasting...
Biological agents and their products commonly cause foodborne illnesses. In the United States it is estimated that there are over 76 million cases of foodborne illnesses each year, resulting in an economic loss of approximately $40 billion. These high figures demonstrate the need for bioassays that display a rapid and...
We isolated and characterized the expression of two genes from Populus
trichocarpa that are homologous to the TERMINAL FLOWER 1 (TFL1) gene from
the model annual plant Arabidopsis. In Arabidopsis, overexpression of the TFL1
gene extends the vegetative growth phase, and the homozygous mutant tfl1 allele
causes early flowering and...
Canopy gap formation is a major factor contributing to maintenance of overstory species diversity and stand structure in forests and may be integral to development of understory shrub and herb layers as well. Acknowledgement of gap formation as a fundamental feature of natural forests has led to consideration of gaps...
This thesis presents a comparison of time-domain and frequency-domain algorithms for phase noise calculation in oscillators. Floquet theory provides the mathematical foundation for these calculations and the numerical methods employ perturbation projection vectors (PPVs). The PPVs are an estimate of an oscillator's sensitivity to noise.
The in-house circuit simulator SPICE3...
Mycobacterium avium is an intracellular pathogen that is associated with disseminated
infection, especially in patients with acquired immunodeficiency syndrome (AIDS). It
appears that patients with AIDS acquire M. avium mostly through the intestinal tract,
and that bacteria enter the intestinal wall at the terminal ileum. Previous studies have
found that...
Habitat loss causes a reduction in available resources for wildlife, alters the configuration of remaining habitat, and may isolate wildlife populations. White-breasted nuthatches (Sitta carolinensis) are experiencing long-term population declines in the Willamette Valley of Oregon, where they are historically associated with oak woodlands. As secondary cavity-nesters, white-breasted nuthatches may...