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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
651

A cross cultural examination of factors influencing exercise during pregnancy

Nevarez, Holly Clements 04 May 2006 (has links)
Overweight and obesity are a growing national concern, particularly among women and selected minority populations (Ayala, Elder, Campbell, Slymen, Roy, Engelberg, et al., 2004; NHANES, 2003). Pregnant women bear a disproportionate risk of becoming overweight or obese (Greene, Smickikias-Wright, Scholl, & Karp, 1988; Gunderson et al., 2000; Rossner, 1999). Although exercise is a key factor in preventing overweight and obesity, women often decrease their exercise levels during pregnancy (McTigue, Garrett, & Popkin, 2002; Viau, Padula, & Eddy, 2002; Zhang & Savitz, 1996). Reported percentages of regular exercise during pregnancy have been documented as low as 5% in a predominately White population (Steele, 2002). Although there is ample evidence demonstrating that Hispanic women exercise less than White women during every other stage of life, little is known about how pregnant Hispanic and White women compare in exercise behaviors (Crespo, Smit, Andersen, Carter-Pokras, & Ainsworth, 2000). The purpose of this research was to study low-income White and Hispanic pregnant women to (1) determine the nature and the extent of exercise behaviors both before pregnancy and during pregnancy (2) identify factors that influence exercise behaviors (3) determine if there are differences in factors that influence exercise between ethnicities. Data were collected via a questionnaire developed by the author. A sample of 301 White and Hispanic pregnant women were recruited through the Women, Infants, and Children [WIC] agencies in four selected counties in Oregon. Although ACOG guidelines provide clear information on the benefits of exercise, over 90% of the women surveyed did not exercise at ACOG guidelines. A majority of the women, 57.8%, actually decreased exercise during pregnancy. Although ethnic differences did not exist in the prevalence of exercise during pregnancy, differences between ethnicities were found in the variety of exercise activities performed and behavioral factors that predicted exercise behavior. Analysis of these differences and the factors contributing to the overall low levels of exercise may provide critical information for future intervention program planning. Well targeted programs will ultimately decrease the excessive weight gain and subsequent increased risk for overweight or obesity that pregnant women face. / Graduation date: 2006
652

Relationships between forest-floor invertebrate distribution, movement, and microclimate under alternative riparian management practices

Rykken, Jessica J. 09 June 2004 (has links)
Graduation date: 2005
653

Oregon's forest sector innovation system : an investigation towards advanced performance

Orozco, Nadine C. 08 June 2012 (has links)
Innovation is a critical component for long term success of an organization. However, being innovative is rarely easy. Successful implementation of any innovation (product, process, or business system) can heavily rely on the functionality of the current innovation system in a given industry. An innovation system is composed of policies, companies, individuals, and other major actors that may play a role in the development and diffusion of an innovation into the marketplace. Historically, the forest products industry has faced numerous challenges in remaining innovative: outside forces provide few incentives or favorable policies while poor communication among industry sectors impedes creative growth from within. An in-depth analysis of why the forest sector innovation system is not performing at a higher level is therefore essential. This thesis outlines results gathered from personal interviews with industry professionals and an industry survey on key policies, incentives, organizations, and the condition of Oregon's forest sector innovation system in general. Ultimately, the research provides recommendations for an improved forest sector innovation system that can, in turn, increase competitiveness and synergies among forest sector companies, higher education, and other businesses in Oregon. / Graduation date: 2013
654

An analysis of Benton County small businesses' emergency and disaster preparedness

Chona, Tiffany L. 03 December 2003 (has links)
Natural Hazards are a potential risk to Benton County small businesses. However, little has been done to help prepare, respond, recover or resume business following a significant disastrous event. 93 small businesses in Benton County responded to a mailed survey, and 10 additional small businesses participated in both mailed surveys and interviews. Information collected from the surveys and interviews were used to assess current disaster preparedness of Benton County small businesses, gauge business owner knowledge about risk reduction tools and techniques, and to better understand small business needs in reducing risk and loss from natural hazards. Overall, businesses were concerned about the potential impacts of natural disasters, but few have taken steps to mitigate these hazards. Trends were identified in interview responses that add valuable information about why businesses have not taken appropriate steps to mitigate hazards. Most small business owners/managers are more concerned about day-to-day activities than they are about planning for natural disasters. Businesses that practiced environmental stewardship and other sustainable business practices tended to be more interested in protecting their business and in training management and employees to prepare, respond, recover, and resume business. Overall, business owners weren't sure how to protect their business from large-scale hazards. The cost versus benefit of emergency and disaster preparedness was of concern for many business owners. Lastly, businesses that provided nonessential services, such as screen-printing for clothing or a furniture store were less prepared for an emergency or disaster event than those who provided a more essential service. / Graduation date: 2004
655

Factors influencing diet composition of beef cattle grazing mixed conifer mountain riparian areas

Darambazar, Enkhjargal 10 October 2006 (has links)
Two trials were conducted to evaluate changes in the quantity, quality, and moisture of available forage in the pasture, and shrub utilization by cattle during a 30-d late summer grazing period (Trial 1) and the effect of cow age (experience) on grazing distribution and diet composition (Trial 2) in mountain riparian areas. In the trial 1, a pasture (44.7 ha) in the Catherine Creek site at OSU���s Hall Ranch in northeast of Oregon was grazed with 30 yearlings and 30 mature cow/calf pairs from early August to early September in 2001, and from late July to late August in 2002. Sampling dates were d 0, d 10, d 20, and d 30 of the grazing period. The forage availability before grazing was 1058 kg/ha and declined to 323 kg/ha at the end of the grazing period (P<0.10). Grasses dominated the pasture, followed by forbs, grasslikes, and shrubs. Kentucky bluegrass was the most prevalent forage species followed by timothy, sedges, and common snowberry. The highest percent disappearances of forage species was (83.7-92.7%) observed with quackgrass, western fescue, California brome, redtop, and heartleaf arnica, though their initial contributions to the available forage were less than 5%. High levels of shrub utilization were observed from d 20 through the end of the grazing period (45% for willow and 59% for alder). Forbs and shrubs did not vary in moisture content between the 10 d intervals and across the years averaging 59% and 61%, respectively (P>0.10). In contrast, the moisture content of grasses were over 50% at the beginning of the grazing period but declined dramatically to 34% from d 10 to d 20. Likewise, forbs and shrubs were higher (P<0.05) than grasses in CP (11, 14, and 6%, respectively) and IVDMD (58, 49, and 42% respectively). In summary, our results suggest that cattle grazing late summer riparian pastures will switch to intensive shrub utilization when grasses decline in quality and quantity, and forbs decline in quantity. In the trial 2, thirty first calf heifers, and thirty mature cows were randomly assigned to four pastures (15 head per pasture, average 21.5 ha) in the Milk Creek site of Hall Ranch from late July to early September of 2000 and 2001. Botanical composition of diets was determined by analyzing the feces from 10 animals (5 per pasture) in each treatment during the fourth week of the trial using the microhistological procedure. Correction factors were calculated for the 22 major plant species. First calf heifers had higher portions of grasses (75% versus 71%; P<0.05), but lower portions of shrubs and trees (9% versus 13%; P<0.10) as compared to mature cow diets, respectively. On an individual species basis, ponderosa pine consumption was a major contributor with mature cows consuming greater quantities (P<0.10) than first calf heifers. In summary, mature cows seem to have selected diet less in the amount of grasses and more in the amount of shrubs and trees as compared to younger cows. / Graduation date: 2004
656

A descriptive analysis of the waterways in Coos Bay Oregon on the basis of general, ruminant and human Bacteroides-Prevotella 16S rDNA markers

Jones, Thomas E. 12 February 2003 (has links)
We explain a new method of detecting non point source fecal contamination using a PCR based method called Touchdown Polymerase Chain Reaction (TD-PCR). Using genetic markers particular to general, ruminant and human Bacteroides- Prevotella genes, we identified presence in both fresh and salt water environments. Water samples from four sites were collected at approximate 2-week intervals for a year. Samples were analyzed for total coliforms, fecal coliforms, E. coli, and the presence of general, ruminant and human Bacteroides-Prevotella markers. We compared the odds of recovering each PCR marker between sites. We investigated the relationship between rainfall and recovery of PCR markers. Finally, we compared the sensitivity of the PCR methods to standard public health methods. / Graduation date: 2003
657

Evaluating Oregon's beach sites and assessing twenty-six coastal beach areas for recreational water quality standards

Benedict, Rae T. 10 June 2003 (has links)
With congressional passage of the BEACH Act in October of 2000, Coastal and Great Lakes states were mandated to assess coastal recreation waters for the application of ambient water quality standards. This research encompasses two components involved in applying the BEACH Act statues to Oregon. The first component was to select beach sites in Oregon. The second component involves applying bacterial recreational water standards to select Oregon beaches. Using the guidelines provided by the United States Environmental Protection Agency (EPA), this study develops a method to appraise Oregon marine recreational waters taking into account the following factors: use, available information, pollution threats, sanitary surveys, monitoring data, exposure considerations, economics, and development. In an effort to protect the public from swimming-associated illness attributable to microbial pollution, 24 beaches were identified in Oregon. Of these, 19 beaches were classified as tier 1, or high priority, and five sites were classified as medium priority, or tier 2. Future studies should be directed at ascertaining the beach lengths utilized by Oregon marine recreators since this is an important parameter in targeting bacterial monitoring. Ongoing monitoring of these 24 sites is warranted and new information could be used to update beach tier levels in Oregon. In the second phase of this study, bacterial monitoring data was used for comparison to recreational water quality standards. In October of 2002, the Oregon Department of Environmental Quality (ODEQ) sampled 26 beaches for enterococci and Escherichia coli (E. coli) densities. Of the water sampled from all 26 beach sites, nine exceeded s single sample maximum density of 104 enterococci colony forming units (cfu) per 100 milliLiters (mL). The Oregon beach with the highest exceedance occurred at Otter Rock's South Cove where the enterococci concentration was 4352 most probable number (MPN)/100 mL. A comparison of the 26 sampled beaches to ODEQ's estuarine E. coli standard of 406 organisms/100 mL resulted in two beaches with exceedances. Otter Rock at South Cove had the highest E. coli concentration at 1850 MPN/100 mL. Based on the limited data used in this study, should Oregon adopt the enterococci standard in lieu of the current ODEQ estuarine E. coli standard, more beaches will have exceedances of the recreational water standard. Additional bacterial monitoring is warranted to further characterize the nature and extent of the problem in Oregon. To protect the health of the marine recreating public, future Oregon marine water quality studies should delineate the "no swim" zone around creeks and model the impacts of rainfall on beach sites. / Graduation date: 2004
658

Hazardous materials commodity flow study for Linn, Benton, and Lincoln counties, Oregon

Wemple, Bryan E. 13 May 1999 (has links)
Hazardous materials data from business and industrial chemical information and incident databases were analyzed to study the types of chemicals located in Linn, Benton, and Lincoln Counties, Oregon. Federal and Oregon Department of Transportation data were analyzed to study traffic patterns and truck and railroad traffic levels. Results indicate more than 2,000 chemical products are reported by businesses and industries in the three counties, with about 1,000 hazardous ingredients. The primary hazard Classes for these chemicals are flammable fuels, corrosives, and poisonous materials. Diesel, heating fuel, gasoline, and related fuels comprised more than 50% of the materials transported in the study area. A Geographic Information System (GIS) was used to input industrial and business locations of hazardous materials, historic hazardous materials incidents, traffic densities, population centers, and traffic network intersections. These metrics were modeled as risk factors for potential hazardous materials transportation risks. For Benton County, these factors were combined with population density and critical facilities themes to provide the basis for overlay and proximity analysis for the purpose of facilitating emergency planning and to foster public awareness. Located on the Interstate 5 corridor, Linn County uses and transports a greater variety of hazardous materials than Benton or Lincoln Counties. For example, fifty-one of fifty-five extremely hazardous substances found in the three county area were reported in Linn County, with 24 reported in Benton County, and 6 reported in Lincoln County. Data from Oregon Department of Transportation were extracted to assess accident and traffic patterns and integrate these risk factors with hazardous materials information. One federal and one state database reporting hazardous materials incidents were analyzed. Although traffic increased on study area roads more than 25% in the last decade, two hazardous materials incidents databases did not indicate an increasing number of emergency spill responses. The Oregon State Fire Marshall's incident database indicated an average of 34 per year between 1988-1997. Linn County averaged 18 per year during this time period, Benton County averaged 13, and Lincoln County averaged 3. Fuels were the primary chemical type responded to. The federal Hazardous Materials Information Reporting System database reported 40 incidents in the highway category and 11 railway incidents. Both types of incidents were dominated by corrosive materials in this database, which does not include fuels as defined hazardous materials. Traffic data on the roads used for hazardous materials transport show much higher traffic densities near intersections with other major roadways and in urban areas. Incident reports followed this pattern, primarily occurring in the major cities and towns of the three counties. Estimated daily numbers of trucks carrying hazardous materials ranged from 6 per day on the coastal portion of Oregon 34, to almost 700 on the section of I-5/99E between Albany and the Linn-Marion County border. Rail data studied indicate the highest quantities of materials designated hazardous were also transported on the main north-south corridor of Linn County, implicating this central area in the three counties has the highest density of the risk factors studied. / Graduation date: 2000
659

Nitrogen available to winter wheat as influenced by previous crop in a moist xeric environment

Qureshi, Maqsood Hassan 06 April 1999 (has links)
Rotating wheat with other crops is a common practice in the Willamette Valley of western Oregon. Depending upon previous crop and soil type, current N fertilizer recommendations for wheat in the Willamette Valley vary widely. Excessive fertilizer poses environmental risk, whereas lower N inputs than required by the crop represent economic losses to growers. Growers and their advisors face the challenge to minimize the environmental risk, and at the same time to maintain or increase economic returns. Questions are often raised concerning the efficient use of N fertilizer and accurately predicting the amount of N needed by wheat following different crops. The first study measured growth, N uptake and N use efficiency (NUE) of winter wheat grown after either a legume or oat for three years. In all three growing seasons, winter wheat showed higher biomass, N uptake and NUE when grown after a legume than after oat. The contribution of legume was evident before the wheat was fertilized in spring, indicating that legume N had mineralized in fall or winter. Contribution of soil N to wheat suggested that fertilizer N can be reduced by 44 kg N ha����� if a legume is grown previously. Nitrogen use efficiency estimated 50 to 70 days after N application by isotopic method (24 to 94%) was comparable with that estimated simply by difference (21 to 94%) at the same time. The second study predicted gross mineralization rates using analytical models. Comparable N mineralization was predicted by a model assuming remineralization and a model assuming no remineralization, suggesting that remineralization was negligible. In the spring, mineralization-immobilization turnover was at a lower pace than expected in both rotations. In two growing seasons, gross mineralization rates were higher where the previous crop was legume (0.37 to 0.74 kg����� ha����� day�����) as compared to where oat was grown previously (0.14 to 0.6 kg����� ha����� day). Negative net mineralization indicated that fertilizer N was immobilized in the oat-wheat rotation. The third study evaluated calibration and digestion techniques used to determine elemental concentration in grasses. Use of a dry ashed standard to calibrate the ICP spectrometer generated highly variable calibration curves and was not a viable calibration method. Good agreement was found between chemical and microwave digested standards. Dry ashing resulted in considerable S and Mn losses, whereas, perchloric acid digestion and microwave digestion showed similar results. Our study suggests that if routine analysis are to be performed for macro nutrients or involve trace level work, the best method is microwave digestion with chemical standard calibration of ICP spectrometer. / Graduation date: 1999
660

Ion exchange membranes and agronomic responses as tools for assessing nutrient availability

Salisbury, Steven Earl 13 July 1999 (has links)
Winter wheat is commonly grown in rotation with leguminous and non-leguminous crops in the Willamette Valley. For agronomic, economic, and environmental reasons it is important to understand the influence of previous crops on availability of N and other nutrients. Objectives of this study were: (1) to evaluate the effects of long-term rotations on winter wheat response to N fertilizer, and (2) to evaluate the use of Plant Root Simulator���(PRS) probes for measuring soil N mineralization and N availability to winter wheat. Field experiments were conducted over three growing seasons in plots of `Stephens' soft white winter wheat at Hyslop farm. Plots receiving 0, 50, 100, 150 and 200 kg N ha����� at Feekes GS 4 were sampled to determine above ground N uptake, grain yield, and grain protein. In spring 1998, PRS probes were placed in 0 kg N ha����� plots and removed at one-week or two-week intervals. In autumn 1998, probes were placed in unfertilized plots and removed at 1-week, 4-week, and 8-week intervals. Probes measured the availability of NH������-N, NO������-N, K���, Ca�����, Mg�����, and P0��������-P. Grain yield and N uptake were greater for wheat following clover as compared to following oats. Three-year average fertilizer equivalent values calculated from N uptake and grain yield data were 44.5 kg N h����� and 49.0 kg N h�����, respectively. The similarity of these independent measurements suggest that differences in N availability were the primary reason for the rotation effect. PRS probes also detected rotational differences in N availability. Average N recovered by probes sampled at 1-week intervals indicated that there was 63% as much NO������-N available to wheat following oat as compared to clover. Wheat recovered 64% as much N following oats as compared to clover. This suggests that PRS probes are an effective method for predicting relative amounts of plant available N. PRS probes also detected rotational differences in plant available potassium. Agronomic responses are useful for assessing the availability of nutrients that are limiting plant growth. PRS probes, on the other hand, are effective for assessing the availability of both limiting and non-limiting nutrients. / Graduation date: 2000

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