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2011

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Microbial Ecology Of Active Marine Hydrothermal Vent Deposits: The Influence Of Geologic Setting On Microbial Communities, Gilberto Eugene Flores Jan 2011

Microbial Ecology Of Active Marine Hydrothermal Vent Deposits: The Influence Of Geologic Setting On Microbial Communities, Gilberto Eugene Flores

Dissertations and Theses

The discovery of deep-sea hydrothermal vents in 1977 revealed an ecosystem supported by chemosynthesis with a rich diversity of invertebrates, Archaea and Bacteria. While the invertebrate vent communities are largely composed of endemic species and exist in different biogeographical provinces, the possible factors influencing the distribution patterns of free-living Archaea and Bacteria are still being explored. In particular, how differences in the geologic setting of vent fields influence microbial communities and populations associated with active vent deposits remains largely unknown. The overall goal of the studies presented in this dissertation was to examine the links between the geologic setting of …

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Youth Voices Of Bounty And Opportunity: High School Students' Experiences With Food And Community, Kara Marie Gilbert Jan 2011

Youth Voices Of Bounty And Opportunity: High School Students' Experiences With Food And Community, Kara Marie Gilbert

Dissertations and Theses

Currently, garden-based research does not include input from young adults about their experiences and perspectives as individuals in garden-based programs, specifically those that address issues of food and community. To address this void, this qualitative research examines youth perspectives and engagement in garden-based community projects in Olympia, Washington, and Medford, Oregon. The sample of 11 students was chosen from these projects that use food as a means to engage the community and educate underprivileged young adults about local food systems. The main question that the research addresses is: Why, and in what ways, are young adults appropriate agents for community …

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Black/White Health Disparities In The U.S. The Effect Of Education Over The Life-Course, Elizabeth Melissa Withers Jan 2011

Black/White Health Disparities In The U.S. The Effect Of Education Over The Life-Course, Elizabeth Melissa Withers

Dissertations and Theses

In the United States there exists a clear and disconcerting racial disparity in the distribution of good health, which can be seen in differential levels of morbidity and mortality affecting blacks and whites. Previous research has examined the role of SES in shaping racial health disparities and recent studies have looked specifically at the effect of education on health to explain the racial disparity in health. Higher levels of education are robustly associated with good overall health for both blacks and whites and this association has been examined over the life-course. This research explores racial differences in the effect of …

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Managing White-Tailed Deer: Midwest North America, Kurt Vercauteren, Scott E. Hygnstrom Jan 2011

Managing White-Tailed Deer: Midwest North America, Kurt Vercauteren, Scott E. Hygnstrom

School of Natural Resources: Faculty Publications

It easily can be said that the white-tailed deer is the most important species of wildlife in the midwestern United States. Approximately 10 million white-tailed deer inhabit the Midwest, which is more than any other region in North America. Further, many of the most impressive whitetails have come from the Midwest (Figure 17.1). Dramatic changes have occurred on the landscape since European settlement that influenced populations of white-tailed deer in this region. Timber harvest in the north and east and agricultural tillage and residential development throughout the region have had both positive and negative impacts on deer numbers. White-tailed deer …

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Biological Erosion Of Marine Habitats And Structures By Burrowing Crustaceans, Timothy Mathias Davidson Jan 2011

Biological Erosion Of Marine Habitats And Structures By Burrowing Crustaceans, Timothy Mathias Davidson

Dissertations and Theses

Marine bioeroders, borers, and burrowers can have drastic effects to marine habitats and facilities. By physically altering the structure of marine habitats, these organisms may elicit ecosystem-level effects that cascade through the community. While borer damage is typically restricted to a few substratum types, burrowing isopods in the genus Sphaeroma attack a diversity of substrata in tropical and temperate systems. My dissertation examined how boring sphaeromatid isopods affect coastal habitats (saltmarshes, mangroves) and other estuarine substrata as well as marine structures. I used a combination of lab and mensurative field experiments to quantify the effects of boring by isopods and …

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Chronology And Ecology Of Late Pleistocene Megafauna In The Northern Willamette Valley, Oregon, Daniel Mcgowan Gilmour Jan 2011

Chronology And Ecology Of Late Pleistocene Megafauna In The Northern Willamette Valley, Oregon, Daniel Mcgowan Gilmour

Dissertations and Theses

This study is an investigation of the timing of extinction of late Pleistocene, large bodied mammalian herbivores (megafauna) and of the environment in which they lived. The demise of the megafauna near the end of the Pleistocene remains unexplained. Owing to potential human involvement in the extinctions, archaeologists have been particularly concerned to understand the causes for faunal losses. Our current lack of understanding of the timing and the causes of the extinctions in North America may result from a deficiency in understanding the histories of each individual species of extinct animal on a local level. Detailed regional chronologies of …

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Improving Hypothesis Testing Skills: Evaluating A General Purpose Classroom Exercise With Biology Students In Grade 9., Michael Gregg Wilder Jan 2011

Improving Hypothesis Testing Skills: Evaluating A General Purpose Classroom Exercise With Biology Students In Grade 9., Michael Gregg Wilder

Dissertations and Theses

There is an increased emphasis on inquiry in national and Oregon state high school science standards. As hypothesis testing is a key component of these new standards, instructors need effective strategies to improve students' hypothesis testing skills. Recent research suggests that classroom exercises may prove useful. A general purpose classroom activity called the thought experiment is proposed. The effectiveness of 7 hours of instruction using this exercise was measured in an introductory biology course, using a quasi-experimental contrast group design. An instrument for measuring hypothesis testing skill is also proposed. Treatment (n=18) and control (n=10) sections drawn from preexisting high …

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The Technological Role Of Bone And Antler Artifacts On The Lower Columbia: A Comparison Of Two Contact Period Sites, Kristen Ann Fuld Jan 2011

The Technological Role Of Bone And Antler Artifacts On The Lower Columbia: A Comparison Of Two Contact Period Sites, Kristen Ann Fuld

Dissertations and Theses

This thesis explore the technological role of bone and antler artifacts from two contact period southern Northwest coast archaeological sites, the Cathlapotle site (45CL1) and the Meier site (35CO5). Technological measures of sedentism are based on lithics, and predict residential sedentism promotes technological expediency in hunter-gatherers (Parry and Kelley 1987). Cathlapotle and Meier lithic assemblages consist of expedient and opportunistic assemblages and raw material stockpiles, with the exception of highly curated projectile points and endscrapers (Hamilton 1994). The expectation that residential sedentism promotes technological expediency in hunter-gatherers was tested on the Cathlapotle and Meier bone and antler artifact assemblages in …

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Effects Of Daily Social Support On Tension-Reduction Drinking, Deborah L. Brannan Jan 2011

Effects Of Daily Social Support On Tension-Reduction Drinking, Deborah L. Brannan

Dissertations and Theses

Researchers have argued that in times of need having supportive, caring people available can make all the difference between achieving optimum health and well-being or suffering from mental or physical illness (Cobb, 1976; Sarason & Sarason, 1985; Thoits, 1986). The direct-effect model of support postulates that having the knowledge of available relationship resources (i.e., perceived support) and receiving benefits from those relationships (i.e., received support) both have beneficial effects on health behaviors and well-being (Cohen & Wills, 1985). According to the stress-buffering model, when stressors are encountered, the certainty of having available resources, as well as having tangible support resources, …

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