2000-2019

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https://hdl.handle.net/10217/100538

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Open Access
Assessment of nutrition education strategies to reduce cardiovascular disease in U.S. Army hospitals
(Colorado State University. Libraries, 2007) Bukhari, Asma Sultana, author; Jennifer Anderson, advisor; Kaminski, Karen, committee member; Gould, Susan, committee member
Cardiovascular disease (CVD) continues to be the leading cause of death in the United States with an estimated 79,400,000 adults diagnosed with this disease in 2004 and costs of $431.8 billion projected this year. As a result there is an increased emphasis on early detection and treatment of risk factors. Military personnel are vulnerable to this killer disease due to indulgence in unhealthy behaviors such as cigarette smoking, physical inactivity, poor nutrition, and increased stress. These behaviors can have a profound impact on the military readiness and mission accomplishment. The purpose of this study was to identify strategies to enhance nutrition education provided to the military personnel at US Anny hospitals to manage CVD. The results will be used to identify weaknesses and gaps in an existing program and facilitate improvement of CVD nutrition education. It was hypothesized that nutrition education can be enhanced by aligning the existing CVD management programs with evidenced based guidelines that will provide program consistency. The target audience for this study was Registered Dietitians in clinical leadership positions at U.S Anny hospitals and outpatient clinics. The study was approved by the Colorado State University Human Research Committee and the U.S Anny Medical Research and Material Command Human Research Protection Office. Survey validity was established by obtaining information from a review of literature and feedback from expert Army dietitians and CSU faculty. Survey reliability was established by a test and re-test during a pilot test on a subset of Army dietitians. The responses were analyzed using computer software and reported as mean, standard deviations and frequencies. The survey response rate was 70% (n=21). The primary educators of CVD risk reduction were dietitian. Sixty-two percent of the hospitals provided nutrition education based on current guidelines. The current program was rated either "very good" or "good" by 67% of the dietitians. Eighty-one percent of dietitians experienced variation in the program at their hospitals. Only 24% of the dietitians indicated a mechanism to reach deployed soldiers with hypercholesterolemia. A web-based resource center was selected by 43% of the dietitians followed by 23% who suggested development of a self-paced web-based education program for deployed or remotely located soldiers. Caution is advised while interpreting the results because the findings are based on dietitians' knowledge and opinions and may not have captured all the services offered to the patients. The survey provided insight into current program and suggestions for future program improvements. Cost effectiveness and improved patient satisfaction of medical nutrition therapy by Registered Dietitians is already established. Army dietitians need to take the lead in designing and implementing programs to reduce the CVD risks among military personnel. Such interventions will improve the quality of life of soldiers by providing long term health benefits; and that, in tum, will save resources from reduction in mortality and morbidity associated with CVD events. It is important to explore various communication media for information dissemination.
Open Access
Development and evaluation of Food friends get movin' with mighty moves™ : a physical activity program to prevent obesity in low-income preschoolers
(Colorado State University. Libraries, 2007) Bellows, Laura Leigh, author; Jennifer Anderson, advisor; Auld, Garry, committee member; Kennedy, Catherine, committee member; Davies, Patricia, committee member
The prevalence of overweight among preschool-aged children in the United States is increasing at an alarming rate. The preschool years provide an opportunity to establish healthful eating and physical activity behaviors which can lessen the growth of obesity. Unfortunately, preschoolers have been largely ignored when it comes to obesity prevention efforts. The overall objective of this project was to design, develop, and evaluate a physical activity program to compliment the Food Friends ® nutrition program in an effort to prevent overweight in young children. Food Friends Get Movin' with Mighty Moves™ is an 18 week program focusing on gross motor development, physical fitness, and physical activity in the classroom environment. This project utilized the steps of social marketing to develop the Mighty Moves™ program. Further, to enhance the likelihood that behavior change would occur, the Social Learning Theory was embedded within the social marketing framework. The Food Friends Get Movin' with Mighty Moves™ study was a randomized controlled trial of 3- to 5-year old children (n=201) enrolled in 8 Head Start centers in Colorado. On-site measures included height, weight, physical fitness (sit-ups, sit-n-reach, shuttle run, 3-minute run), and gross motor skill (Peabody Developmental Motor Scales) assessments. BMI, BMI z-score and BMI percentiles were calculated. Additionally, physical activity was assessed by pedometers over a 6-day timeframe (4 weekdays and 2 weekend days), and daily step counts were recorded by parents. Characteristics of the study population indicated a high prevalence of overweight, low physical activity levels, and average to below-average motor skills. The intervention did not have an effect on weight status but did improve gross motor skills and fitness levels. Lastly, no difference was found for physical activity by treatment. The success of Mighty Moves™ at increasing gross motor skills and physical fitness in preschoolers, in concert with the Food Friends® program's demonstrated ability to increase children's willingness to try new foods, has contributed to the establishment of healthful behaviors for proper growth and development in the early years. These behaviors serve as foundations to building healthy lifestyles, which may decrease the risk of overweight later in life.
Open Access
Effectiveness of a Web-based nutrition education program to reduce cardiovascular disease risk among U.S. Army personnel and their families ("Defend your heart" study)
(Colorado State University. Libraries, 2009) Bukhari, Asma Sultana, author; Jennifer Anderson, advisor; Kaminski, Karen, committee member; Harris, Mary, committee member; Gould, Susa Martin, committee member
Cardiovascular disease (CVD) continues to be the leading cause of mortality and morbidity in the United States. Military personnel are also vulnerable to this killer disease due to indulgence in unhealthy behaviors such as cigarette smoking, physical inactivity, poor nutrition, and high stress. Formative assessment identified a need for web-based resources for the Army registered dietitians (RDs) and for deployed or remotely located military beneficiaries. The purpose of the current study was to create and assess the effectiveness of a web-site "Defend Your Heart". This web-site was targeted to two audiences: RDs and a self care program for the military beneficiaries. This self care program was created using the framework of Rosenstock's Expanded Health Belief Model (EHBM). The effectiveness of a web-based self care program was evaluated using a randomized 4-month study with participants either in the web-based group (n=17) or the usual care (n=13) at a U.S. Army hospital. Data were collected at baseline, two months and four months. Variables measured were anthropometric, blood pressure, lipid profile, fasting glucose, C-reactive protein, nutrient intake, physical activity, and EHBM constructs. Data were analyzed using analysis of covariance and using baseline means to adjust the two and four month data. Results indicated a significant reduction of total blood cholesterol, LDL-cholesterol, predicted body fat percent, and estimated body mass index (P<0.05) in the web-based group. The usual group demonstrated a significant increase in self-efficacy score at month four (p<0.05). Significant within group changes for both groups were demonstrated for the reduction in waist circumference and serum triglycerides (p<0.05). Due to a smaller sample size caution is required while interpreting the results. The results of the web-site usability showed that a majority of the RDs (n=34) and web-based participants (n=8) were satisfied with the content and ease of navigation. RDs and web-based groups suggested enhancing web-site eye appeal, interactivity, and printing capability. Web-based programs may serve as an effective alternate mechanism of delivering CVD risk reduction education. The U.S Army needs to invest in further research to launch an effective web-based program for military beneficiaries to reduce CVD risk factors.
Open Access
Developing and evaluating a website on infant feeding, specifically breastfeeding, for child care providers
(Colorado State University. Libraries, 2006) Clark, Alena Michelle, author; Jennifer Anderson, advisor; Adams, Elizabeth, committee member; Baker, Susan, committee member; Barrett, Karen, committee member
Research studies have shown that breastfeeding provides a multitude of benefits to infants, mothers and communities. Yet, many women cease breastfeeding before the recommended times. A common reason women cease breastfeeding is because of returning to work or school. Because child care providers often provide care to these infants, further research on the role of child care providers on infant feeding practices, specifically breastfeeding, is warranted. This research project occurred in three phases. First, a needs assessment survey was conducted to determine the knowledge, attitudes, behaviors and training needs of child care providers on infant feeding, specifically breastfeeding, in child care centers. The most appropriate medium to integrate best practice information and provide educational tools to child care providers was also examined. Based on the first phase of this project, a website for child care providers on infant feeding, specifically breastfeeding, was determined to be the desired medium for child care providers. Because no other infant feeding website for child care providers was available, InfaNET Nutrition for Child Care Providers website was developed during the second phase of this project based upon the needs assessment results and facilitated group discussions' feedback. The Social Learning Theory was used as the theoretical framework for the development of the content information on the website. A process evaluation with infant feeding experts, child care providers and web design experts deemed the website ready to be tested. Thirdly, a quasi-experimental research design with a control and intervention group was completed. The target population viewed the website as a well-liked and effective means to provide infant feeding information. Results also showed that between the pre- and post-test intervention, the intervention group had more statistically significant positive changes in attitude and behaviors than the control group. Child care providers already possessed a desirable level of knowledge in regards to storing, preparing and feeding infants' breastmilk and formula, but not in distinguishing hunger cues or introducing solid foods. The behavior and attitude changes were not sustained at follow-up, but results showed there was a non-significant positive trend in knowledge for the intervention group.
Open Access
Development and evaluation of a bilingual interactive multimedia computerized food recall
(Colorado State University. Libraries, 2004) Zoellner, Jamie Marie, author; Jennifer Anderson, advisor; Adams, Liz, committee member; Auld, Gerry, committee member; Middlemist, Dennis, committee member
The objective of this research was to utilize advancements in computer technology to develop and test a bilingual interactive multimedia (IMM) dietary assessment tool. During developmental testing 25 peer-reviewers rated characteristics of the program on a 5-point Likert scale. The mean score of each question received high ratings including introduction/directions helpful (M = 4.5), meal times understandable (M = 4.6), foods easy to identify (M = 3.9), portions easy to identify (M = 4.5), and computer food recall easy to use (M = 4.5). In the final format, the bilingual IMM recall represents a multiple-pass method in which users first report food choices from 167 graphically represented foods. After the development and formative evaluation, the IMM recall underwent comparative validity testing against an interview-administered dietary recall. This study was a two-period cross over design study with repeated measures. Subjects were randomly assigned to complete an IMM recall or interview-administered 24-hour recall first. The interview-administered recall was analyzed using the Food Intake Analysis System (FIRS) and the EFNEP Reporting System (ERS). The effect of substituting standardized portion sizes for reported portion sizes was examined. Of 80 adult Coloradoan participants, 71 (91%) were female, 45 (56%) had ≤12th grade education, 65 (81%) had ≤$15,000 annual income, and 21 (26%) completed the IMM recall in Spanish. Analysis of variance and unadjusted and energy-adjusted correlations were used for analysis. No significant group differences were found for order of administration or demographic characteristics. The only significant method effect found was between the IMM recall and FIRS for vitamin C (P = 0.025). The unadjusted correlations between the IMM recalls and interview-administered recalls analyzed using both FIRS and ERS were generally around 0.6. Energy-adjusted correlations consistently decreased. Substituting standardized portion sizes resulted in significant differences for six nutrients and caused all correlations to drop. Overall, the IMM recall was found to be valid for assessing dietary intake by groups of individuals. This IMM recall has been well received in the peer-review process and attracted the interest of nutrition educators. The results of comparative validity testing and positive reactions received from participants and nutrition educators indicate diet assessment utilizing IMM holds tremendous potential.
Open Access
The effectiveness of an Internet-based nutrition and fitness education program for senior military officers
(Colorado State University. Libraries, 2004) Sigrist, Lori D., author; Jennifer Anderson, advisor; DeVoe, Dale, committee member; Kennedy, Cathy, committee member; Auld, Garry, committee member
A six-month Internet-based nutrition and fitness education program, entitled Taking Command of Your Health, to improve diet and fitness behaviors and physiological measures in a group of senior military officers enrolled in the Distance Education course at the U.S. Army War College. The intervention was based on the Transtheoretical Model (TTM) for behavior change and was delivered via the Internet. A needs assessment survey assessed senior military officers' health concerns, educational preferences for nutrition and health topics, eating habits, and motivators and barriers for eating healthfully and exercising regularly. Survey results determined the content of the intervention. Participants were randomly assigned to either a control group that did not have access to the website intervention or to the treatment group that had access to the program. The program was designed in a monthly newsletter format which combined nutrition and fitness information. Staging algorithm surveys determined stage of change for diet and exercise for participants each month. Participants were provided with stage-matched education based on the diet algorithm and all participants received identical fitness information regardless of stage for exercise. To evaluate the program, treatment participants completed exit surveys at the end of the intervention. Results of the study indicate that an intervention based on the TTM did not result in statistically significant improvement in behavioral and physiological measures between treatment and control groups. The program was effective in significantly progressing treatment participants through the stages for diet behavior, but not for exercise behavior. Unfortunately, dietary behavior change was not maintained as participants regressed to earlier stages after the intervention. In the exit survey, participants reported that they liked receiving health information over the Internet and they would recommend a similar program to others in the military. Future research on the implementation of a theory-based intervention should focus on an individual's cognitive and behavioral processes that determine one's success and failure with behavior change, factors that determine participation and regular usage of a website program, and the impact of program duration and content on other military populations.
Open Access
Examining the application of the transtheoretical model of change for fruit and vegetable consumption among college students
(Colorado State University. Libraries, 2002) de Oliveira, Maria do Carmo Fontes, author; Jennifer Anderson, advisor; Kendall, Patricia, committee member; Auld, Garry, committee member; Morgan, George, committee member
Nutrition education messages about the adequate amount of fruits and vegetables in the diet have the potential to disseminate information the optimum level of fruit and vegetable intake to the population. However, this potential will be effective, only if the audience incorporates these messages. To facilitate the acceptance of nutrition education messages, we need to understand the process of behavior change across different behaviors and cultural/ethnic groups. The main purpose of this study was to examine the applicability of the Transtheoretical Model for fruit and vegetable eating behavior in male North American, Latino and Asian college students at Colorado State University. First, a 40-item scale was developed to measure the processes of change. Second, stages of change for eating five fruits and vegetables a day were assessed. Third, the relationship between stages of change and processes of change constructs for fruit and vegetable consumption was examined. Results showed that the developed scale was reliable and valid for the target population. Most of the participants were classified as in the preparation or contemplation stages of change, and the stage classification was significantly related to the participant's cultural/ethnic background. North American and Latino participants were predominantly in preparation while Asian participants were in precontemplation. In addition, the North American and Latino groups used less processes of change (stimulus control, dramatic relief and environment reevaluation) than the Asian group. The relationship between stages of change and processes of change indicated that generally the processes of change scores for fruit and vegetable intake were lower in early stages of change than in later stages of change. The finding that each cognitive/experiential composite score was higher than behavioral composite scores across stages of change did not agree with most studies in smoking, but agreed with some studies on diet and exercise. Although more research needs to focus on the applicability of the stages of change and processes of change constructs, the present study provides partial evidence of the value of the Transtheoretical Model in fruit and vegetable eating behavior in the nutrition education arena.
Open Access
Development and evaluation of a lifestyle physical activity intervention for obese sedentary women
(Colorado State University. Libraries, 2001) Byfield, Cynthia Louise, author; Jennifer Anderson, advisor; Sampson, David A, committee member; Hill, James O., committee member; Kennedy, Cathy, committee member
Physical inactivity has been established as an independent predictor of cardiovascular disease (CVD) mortality in both lean and obese individuals. Increasing physical activity and cardiorespiratory fitness (CRF) in obese individuals attenuates the comorbidities associated with obesity and the reduction in risk is comparable to that of smoking cessation. Despite the benefits of physical activity, prevalence of physical inactivity is high , particularly among obese women. Recent evidence indicates that lifestyle physical activity programs that are based on behavior change theory are an effective alternative to traditional exercise programs in promoting the adoption of physical activity in sedentary individuals. The primary aim of this study was two-fold : 1) Develop a 24-week, theory-based lifestyle physical activity intervention for obese sedentary women; 2) Evaluate the effectiveness of this intervention by assessing changes in physical activity and CRF after 24 weeks of intervention and 24 weeks of follow-up. Secondary aims were to examine the effect of the Lifestyle intervention on dietary practices, CVD risk factors, and psychological measures of behavior change. Fifty-eight obese sedentary women were randomized into the Lifestyle intervention developed for this study (n=29) or a "Usual Care" intervention (n=29). After 24 weeks, significant improvements in physical activity, CRF, Body Mass Index (BMI), diastolic blood pressure, self-efficacy, and eight of the 10 processes of change occurred among Lifestyle participants. No changes in these variables were observed among Usual Care participants. Attrition was significantly lower among Lifestyle participants than among Usual Care participants. After 48 weeks, levels of physical activity , CRF, and self-efficacy were significantly higher than baseline among Lifestyle participants but not among Usual Care participants. LDL-cholesterol levels were significantly lower in Lifestyle participants at 48 weeks but systolic blood pressure was significantly higher. BMI was significantly higher at 48 weeks than at baseline among Usual Care participants but not among Lifestyle participants. The Lifestyle intervention developed for this study was effective in producing significant improvements in physical activity, cardiorespiratory fitness, LDL-cholesterol, and self-efficacy among obese sedentary women.
Open Access
Development and evaluation of a bilingual nutrition education computer program for Latino children
(Colorado State University. Libraries, 2001) Serrano, Elena Lidia, author; Jennifer Anderson, advisor; Kendall, Pat, committee member; Fritz, Janet, committee member; Zimmerman, Don, committee member; Auld, Garry, committee member
Interactive computer technology and multi-media have advanced in the past ten years as growing opportunities for nutrition education. Few nutrition education computer programs exist for school-aged children, particularly for Latinos. The overarching purpose of this research was to develop a computer nutrition program for low-income Mexican American children in Colorado. This research project spans all levels of software development -with formative evaluation , product development, and evaluation. Development of the CD-ROM program was driven by several theoretical models and results from the formative evaluation . The formative evaluation included focus groups with children and surveys with classroom teachers and media teachers in order to determine preferences for computer programs, particularly in classroom settings. We also sought to address dietary acculturation in the program. Food frequency questionnaires and acculturation scales were administered to children in largely Hispanic areas of Colorado. Several foods were found to be sensitive to change with increasing acculturation -- such as posole, corn tortillas, fresh corn , mangoes, Mexican cream, and beans - and sensitive to adoption . The final computer program contained a total of six components -- including educational modules, games, songs, and infomercials -- focusing on the Food Guide Pyramid and related topics. Foods included in the program were representative of different levels of acculturation (as determined by the dietary acculturation study) . Online evaluation was used to measure gains in knowledge, attitudes, and behavior intentions, as well as dietary choices. The program was implemented in a total of four schools -- two intervention schools and two matched control schools -- in southern Colorado. The computer nutrition education program proved to be highly effective in improving knowledge about the Food Guide Pyramid. The intervention group's knowledge of the Food Guide Pyramid increased by over 50% and was considered significantly higher than the control group at the p<.01 level. Self-efficacy related to using the Food Guide Pyramid to plan meals and snacks also increased significantly. Our findings demonstrated that games and songs were effective in strengthening knowledge about nutrition and the Food Guide Pyramid, regardless of acculturation level. Online data about dietary patterns confirmed findings from the preliminary dietary acculturation study.
Open Access
Efficacy of the transtheoretical model in improving exercise and dietary habits in enlisted Air Force personnel
(Colorado State University. Libraries, 2001) Veverka, Donald Victor, author; Jennifer Anderson, advisor; Auld, Garry, committee member; Coulter, Gary, committee member; Kennedy, Cathy, committee member; Chapman, Philip, committee member
As a means of maintaining a fit and ready force, the United States military establishment has always incorporated fitness and weight standards for its personnel. According to data obtained by the U.S. Air Force (USAF) Surgeon General's Office, most personnel pass their fitness tests. However, one particular segment, men between 30 to 44 years of age, have lower scores and appear to have more difficulty passing. Although the USAF has existing nutrition and exercise programs to assist efforts towards greater physical fitness levels and improved dietary habits, these programs may only be suited for individuals that are motivated to improve these behaviors. According to the literature, there are individuals that may need to improve dietary and physical activity behaviors but are not motivated to do so. A more effective approach, according to previous behavior change studies, is to implement a strategy, which uses stage-matched interventions based on the Transtheoretical model (TTM). In short, devise programs that correctly identify an individual's motivation for engaging in a health behavior (stage of readiness to improve) and then match the appropriate intervention for the individual. Using male enlisted Air Force personnel between the ages of 30-44 as the target population, focus groups were used to obtain qualitative information on diet and exercise habits to improve fitness scores. Results revealed that participants needed assistance in obtaining information concerning both diet and exercise in order to successfully define and implement a program which would lead to increased fitness . Further, participants selected various methods by which to receive this information. Specifically, to help increase their physical activity, participants needed further education on cycle ergometry, goal-setting, and ways to avoid injury during exercise. In order for test subjects to develop healthy eating habits, the group was provided information on how to sort out media misinformation, prepare healthy foods quickly, understand food labels and determine safety and efficacy of popular dietary supplements. Handout literature, web sites and seminar/discussion formats were the most effective ways for test subjects to receive information. Using the qualitative focus group data from the aforementioned target population, an intervention program based on the TTM was developed and provided via the worldwide web. Use of interactive technology such as computers and the Internet are strongly advocated by health promotion professionals as an effective means of reaching large numbers of at risk populations with specifically tailored information. There was no evidence that treatment group exposure to the web site program was effective in increasing fitness scores. The data suggest that the physical activity-tailored information content was not effective in encouraging greater exercise intensity which positively impacted fitness levels. However, the dietary-tailored information appears to have encouraged the adoption of more positive nutritional practices, as manifested by the beneficial effects seen in certain secondary outcomes. Stage progression was evident as more treatment subjects than controls advanced to higher stages of positive dietary and exercise behaviors. More treatment group subjects reported improved dietary behaviors than reported increases in exercise behaviors. Treatment subjects did not report any relapse in physical activity as opposed to control subjects who reported a high level of regression towards sedentary physical behaviors.
Open Access
Effects of background winds and temperature on bores, strong wind shears and concentric gravity waves in the mesopause region
(Colorado State University. Libraries, 2009) Yue, Jia, author; She, Chiao-Yao, advisor; Reising, Steven C., advisor
Using data from the CSU sodium lidar and Kyoto University OH airglow imager at Fort Collins, CO, this thesis provides a comprehensive, though qualitative, understanding for three different yet related observed fluid-dynamical phenomena in the mesopause region. The first project involves the convection-excited gravity waves observed in the OH airglow layer at 87 km. Case study on May 11, 2004 is discussed in detail along with statistical studies and a ray-tracing modeling. A single convection source matches the center of the concentric gravity waves. The horizontal wavelengths and periods of these gravity waves were measured as functions of both radius and time. The weak mean background wind between the lower and middle atmosphere determines the penetration of the gravity waves into higher altitude. The second project involves mesospheric bores observed by the same OH imager. The observation on October 9, 2007 suggests that when a large-amplitude gravity wave is trapped in a thermal duct, its wave front could steepen and forms bore-like structure in the mesopause. In turn, the large gravity wave and its bore may significantly impact the background. Statistical study reveals the possible link between the jet/front system in the lower atmosphere and the large-scale gravity waves and associated bores in the mesopause region. The third project involves the relationship between large wind shear generation and sustainment and convective/dynamic stabilities measured by the sodium lidar at the altitude of 80-105 km during 2002-2005. The correlation between wind shear, S, and Brunt-Vaisala frequency, N suggests that the maximum sustainable wind shear is determined by the necessary condition for dynamic instability of Richardson number, leading to the result that the maximal wind shear occurs at altitudes of lower thermosphere where the atmosphere is convectively very stable. The dominate source for sustainable large windshears appears to be the semidiurnal tidal-period perturbations with shorter vertical wavelengths and greater amplitude.
Open Access
Epidemiology and veterinary public policy
(Colorado State University. Libraries, 2008) Zepeda Sein, Cristóbal Andrés, author; Salman, Mo, advisor
Official Veterinary Services are increasingly required to base veterinary public policy decisions on scientific grounds, epidemiology and risk analysis play an important role in shaping these decisions. A formal, in-depth analysis of the multiple interactions between epidemiology, risk analysis and veterinary public policy was conducted to enable decision-makers to direct resources more efficiently and facilitate compliance with international agreements, in particular the Agreement on the Application of Sanitary and Phytosanitary Measures (SPS) of the World Trade Organization. The SPS Agreement recognizes the World Organization for Animal Health (OIE) as the international organization responsible for developing animal health standards. The OIE's Terrestrial Animal Health Code contains scientifically based recommendations for international trade in animals and animal products. However, to date, these recommendations have not been assessed from a risk-based perspective. The study is divided in two major sections: (1) the role of epidemiology in veterinary public policy and (2) the application of risk-based approaches to the assessment of international animal health standards. The first section addresses the international framework, risk analysis and its use worldwide, and the development of international standards. The second section focuses on quantitative risk assessment approaches for the international movement of animals and products, as well as the application of compartmentalization to aquaculture production systems emphasizing the use of a HACCP approach to biosecurity.
Open Access
The animal paradox: animals, sovereignty and the politics of eating
(Colorado State University. Libraries, 2008) Young, Katherine E., author; Macdonald, Bradley J., advisor; Chaloupka, William J., advisor
Looking at the history of political thought, it becomes clear that animals are the decisive political exception in Western politics. It is not that animals are simply excluded in the history of political thought, however, but that they are "inclusively excluded," demarcating the constitutive outside of politics. In other words, animals are characterized as unable to differentiate themselves from their world because they are irrational, speechless and/or appetite driven, and for these reasons, they function as markers for the state of nature and the exit point of politics. Expanding the Italian political theorist Giorgio Agamben's work on the state of exception, it appears that the sacrifice of animal bodies-not simply the idea of animality-becomes vital to sustaining key political concepts like sovereignty, democracy and rights. More specifically, there is an underlying politics of eating that nourishes the Western canon. In the simplest terms, the politics of eating is a secular transubstantiation of sovereign power, in which meat is the material good (signifying the good life) that is consumed by political subjects to mitigate the tension between individual and state sovereignty. Of course, this economy of relations is exacerbated under late capitalism. With the advent of the animal rights movement, however, animals are now drawn into this anthropological political space. Yet, because so many animal advocates (scholars and activists alike) embrace traditional understandings of rights, democracy and sovereignty, they inadvertently support juridical forms that undermine their projects. With this in mind, and given the exceptional political state of animals, it is timely to think about new political strategies that take seriously the irony of animals within the larger context of politics as well as restore the public spectacle of meat, in order to reveal and disrupt the sacrificial politics of eating, which includes both humans and animals.
Open Access
Characterization of integrated optical waveguide devices
(Colorado State University. Libraries, 2008) Yuan, Guangwei, author
At the Optoelectronics Research Lab in ECE at CSU, we explore the issues of design, modeling and measurement of integrated optical waveguide devices of interest, such as optical waveguide biosensors and on-chip optical interconnects. A local evanescent-field array coupled (LEAC) sensor was designed to meet the needs for low-trace biological detection without florescent chemical agent aids. The measurement of LEACs sensor requires the aid of either a commercial near-field scanning optical microscope (NSOM) or new proposed buried detector arrays. LEAC sensors were first used to detect pseudo-adlayers on the waveguide top surface. These adlayers include SiNx and photoresist. The field modulation that was obtained based on NSOM measurement was approximately 80% for a 17 nm SiNx adlayer that was patterned on the waveguide using plasma reactive ion etching. Later, single and multiple regions of immunoassay complex adlayers were analyzed using NSOM. The most recent results demonstrated the capability of using this sensor to differentiate immunoassay complex regions with different surface coverage ratio. The study on buried detectors revealed a higher sensitivity of the sensor to a thin organic film on the waveguide. By detecting the optical intensity decay rate, the sensor was able to detect several nanometer thick film with 1.7 dB/mm/nm sensitivity. In bulk material analysis, this sensor demonstrated more than 15 dB/mm absorption coefficient difference between organic oil and air upper claddings. In on-chip optical interconnect research, optical waveguide test structures and leaky-mode waveguide coupled photodetectors were designed, modeled and measured. A 16-node H-tree waveguide was used to deliver light into photodetectors and characterized. Photodetectors at each end node of the H-tree were measured using near-field scanning microscopy. The 0.5 micrometer wide photodetector demonstrated up to 80% absorption ratio over just a 10 micrometer length. This absorption efficiency is the highest among reported leaky-mode waveguide coupled photodetectors. The responsivity and quantum efficiency of this photodetector are 0.35 A/W and 65%, respectively.
Open Access
Characterizing the fluorescence intermittency of individual cadmium selenide/zinc sulfide quantum dot clusters with spatially correlated single molecule fluorescence spectroscopy and atomic force microscopy
(Colorado State University. Libraries, 2008) Yu, Ming, author; Van Orden, Alan K., advisor
In this thesis, I describe work done to study the optical behaviors of CdSe/ZnS quantum dots, especially the fluorescence blinking behavior of small quantum dot clusters. QDs have unique optical properties that impart several key advantages over molecular dyes. However, when examined at the single-molecule level, QDs emission exhibit novel fluorescence intermittency, or "blinking," behavior. This blinking is believed to be caused by trapping and de-trapping of the photoexcited carriers, causing the QDs to fluctuate between emissive and non-emissive states. A spatially correlated single molecule fluorescence spectroscopy and atomic force microscopy (AFM) apparatus was used to carry out these studies. Single molecule spectroscopy examines the blinking behavior of individual, isolated QDs and QD clusters, while the AFM images the nanometer scale topography of the particles. When multiple isolated QDs were probed simultaneously, the fluorescence behavior was consistent with independent blinking of the individual QDs. However, when close-packed QD clusters were probed, the fluorescence intermittency became much more rapid and intense than could be explained by the summation of multiple particles blinking independently. This suggests when the small QDs aggregate together, they become electronically coupled in some way that enhances the fluorescence blinking. Subsequently, we studied variations of the emission wavelengths of isolated small QD clusters possessing the enhanced blinking behavior. The emission wavelength of the coupled enhanced blinking is red shifted relative to that of normal blinking. We propose that red-shifting in emission is one of the characteristics of electronic coupling in the QD clusters and resulted from the quantum confinement Stark effect. In the following chapters, environment and substrate dependence were also studied. Compared with ambient air, dry nitrogen decreases the population, intensity and/or durations of "on" times. Both CTAB- and Mg 2+-mica substrates quench the fluorescence of single QDs and QD clusters, which is due to the dissociation of electron hole pairs of excited QDs by the electron attractive sites in CTAB molecules and Mg2+ ions.
Open Access
Enantioselective rhodium-catalyzed [2+2+2] and [4+2+2] cycloaddition reactions of alkenyl heterocumulenes: applications to alkaloid synthesis
(Colorado State University. Libraries, 2009) Yu, Robert Tzu Hsiang, author; Rovis, Tomislav, advisor
An intermolecular rhodium-catalyzed [2+2+2] cycloaddition of alkenyl isocyanates and internal alkynes has been developed. In the presence of a catalytic amount of [Rh(C2H4)2Cl]2 and P(4-MeO-C6H4)3, the cycloaddition produces substituted indolizinones and quinolizinones with newly formed sp 3-stereocenters. Depending on the alkynyl partners, a CO migration process can be involved during the cycloaddition to furnish cycloadducts possessing vinylogous amide functionality. The use of TADDOL-based phosphoramidite ligands on rhodium allows for the incorporation of terminal alkynes in a highly enantioselective [2+2+2] cycloaddition with alkenyl isocyanates. Terminal alkyl alkynes provide bicyclic lactams, while the use of aryl alkynes provides complementary access to vinylogous amides through a CO migration process. Product selectivity seems to be governed by a combination of electronic and steric factors, with smaller and/or more electron-deficient substituents favoring lactam formation. The synthetic utility is demonstrated in an expedient asymmetric total synthesis of the alkaloid (+)-lasubine II. A highly enantioselective rhodium-catalyzed [2+2+2] cycloaddition of terminal alkynes and alkenyl carbodiimides has been realized. The cycloaddition with aryl alkynes provides complementary selectivity to the reaction previously described using isocyanates. In addition, this reaction demonstrates the feasibility of olefin insertion into carbodiimide-derived metalacycles, and provides a new class of chiral bicyclic amidines as the major products. A new catalyst system has been realized. The use of chiral biphenyl-based phosphoramidite ligands on rhodium provides an efficient cycloaddition between terminal alkyl alkynes and alkenyl isocyanates. The cycloaddition proceeds through a CO migration pathway, and generates various 5-alkyl indolizinone products with high enantiomeric excess. A four-step asymmetric synthesis of indolizidine (-)-209D has been achieved. A highly enantioselective rhodium-catalyzed [4+2+2] cycloaddition of terminal alkynes and dienyl isocyanates has been developed. The cycloaddition provides a rapid entry to highly functionalized and enantioenriched bicyclic azocines. This reaction represents the first [4+2+2] cycloaddition strategy to construct nitrogen-containing eight-membered rings.
Open Access
Enhancing natural treatment systems by utilizing water treatment residuals
(Colorado State University. Libraries, 2008) Yarkin, Mustafa, author; Carlson, Kenneth H., advisor
The current project envisions the application of riverbank filtration (RBF) and aquifer recharge and recovery (ARR) in series as preliminary treatment steps of a multi-barrier treatment approach for the City of Aurora's Prairie Waters Project. The primary focus of the project is the removal of phosphorus, nitrogen, and carbon from the source water resulting in biologically stable water that can be stored in a terminal reservoir. In addition to nutrients, perchlorate and three commonly used pesticides, atrazine, alachlor, and metolachlor have been studied in terms of removal with the RBF and ARR systems. Aluminum based water treatment residual (WTR) was considered along with other sorbents for enhanced phosphorus removal. The experimental studies include the monitoring of an RBF field site and pilot columns that simulate RBF and ARR systems. Possible benefits of WTR as an amendment were tested by amending a column with 30% WTR under RBF and ARR conditions. Also an application scenario of RBF followed by a WTR amended ARR infiltration basin and ARR was simulated by a column study. Results of the studies indicated that the RBF and ARR systems are insufficient to provide sustainable phosphorus removal. Phosphorus removal mechanism is limited by the sorption capacity of the alluvial sand and minor biological activity. Use of the WTR amendment reduced phosphorus levels to less than the method detection limit of 0.03 mg/L with a high adsorption capacity. The ARR system in sequential RBF-ARR application suffers from the lack of labile organic carbon and therefore microbially mediated treatment processes are limited. Amending the infiltration of the ARR system with organic carbon rich WTR can promote biological activity, thus allowing further biodegradation of contaminants. Results of the study indicated that the RBF system is a sustainable barrier for nitrate removal while labile carbon limited ARR cannot achieve significant nitrate removal. To use the ARR system as a secondary barrier for nitrate, a labile carbon source should be introduced to the system. WTR was used as a supply of organic carbon to the ARR system and the experimental studies indicated that, once optimized, WTR can promote biological denitrification through the ARR system. The field and column studies also showed that both RBF and ARR can achieve perchlorate removal as long as sufficient electron donating compounds (e.g. organic carbon) are present in the environment. It has also been observed that the ability of RBF and ARR systems to remove alachlor and metolachlor is limited by the biodegradation through the alluvial sand while they achieve sustainable atrazine removal. WTR was tested as an amendment alternative the ARR infiltration basin. Concentrations of selected pesticides were reduced to the method detection limit of 0.3 μg/L during 1-foot 30% WTR amended column treatment with the residence time of 1.25 days under both abiotic and biotic conditions. The overall study suggested that once the source and type of the WTR was selected, the optimum amount of WTR can be obtained by adjusting the application ratio and the media depth for the efficient removal of all contaminants of concern.
Open Access
Combinatorial discovery and optimization of novel metal oxide materials for photoelectrolysis using visible light
(Colorado State University. Libraries, 2008) Woodhouse, Michael, author; Parkinson, Bruce, advisor
Efficient and inexpensive production of hydrogen from water and sunlight has been the "holy grail" of photoelectrochemistry since Fujishima and Honda first demonstrated the feasibility of the process by illuminating TO2 single crystals with UV light. While it was a great proof of concept, a more suitable material will most likely be an oxide semiconductor containing multiple metals that will each contribute to the required properties of stability, light absorption, and being catalytic for hydrogen or oxygen evolution. Therefore we developed a high throughput combinatorial approach to prepare overlapping patterns of metal oxide precursors onto conducting glass substrates that can be screened for photolectrolysis activity by measuring the photocurrent generated by rasterng a laser over the materials while they are immersed in an electrolyte. A ternary oxide containing cobalt, aluminum and iron, and not previously known to be active for the photoelectrolysis of water, was identified using the combinatorial technique. The optimal composition and thickness for photoelectrochemical response of the newly identified material has been further refined using quantitative ink jet printing. Chemical analysis of bulk and thin film samples revealed that the material contains cobalt, aluminum and iron in a Co3O 4 spinel structure with Fe and Al substituted into Co sites with a nominal stoichiometry of Co3-x-yAlxFeyO4 where x and y are about 0.18 and 0.30 respectively. The material is a p-type semiconductor with an indirect band gap of around 1.5 eV, a value that is nearly ideal for the efficient single photoelectrode photoelectroylsis of water. Photoelectrochemical measurements indicate that the material has a respectable photovoltage but the photocurrent is limited by the slow kinetics for hydrogen evolution. This new cobalt iron aluminum oxide is most likely not the "holy grail" of photoelectrochemistry that we seek, but our methodology gives a rational approach for future materials discovery and optimization.
Open Access
Indirect electrochemical detection of DNA hybridization based on catalytic oxidation of cobalt(II) and concentration gradient formation in redox conducting polymers
(Colorado State University. Libraries, 2008) Xue, Di, author; Elliott, C. Michael, advisor
Since the new concept was introduced back in 1993, efforts to develop electrochemical methods for detecting nucleic acid hybridization (e.g., DNA) have mushroomed. Compared with nearly all other analytical techniques, electrochemical instrumentation is inexpensive, robust, and relatively simple to operate. The first part of the dissertation (Chapter 1 to Chapter 4) describes the development of a novel electrochemical DNA sensor based on catalytic oxidation of a cobalt bipyridine "mediator molecule" on an ITO electrode. Interaction of the surface bound DNA probe with the DNA target results in formation of hybrid duplex, which subsequently brings redox catalyst molecules from solution to the electrode surface. The mode of selective catalyst binding is intercalation between base pairs of ds-DNA. This surface-bound catalyst "turns on" the redox chemistry of the mediator molecule which is otherwise kinetically inert to oxidation on ITO. With this approach, we demonstrate detection of a 20-mer DNA target oligonucleotide at picomolar concentrations with outstanding signal-to-noise. The second part of our research (Chapter 5) mainly concerns redox polymer films containing permanently locked concentration gradients. Upon redox gradient formation, the conducting polymer displays interesting properties, such as solid diode behavior and electroluminescence. Previous methods explored drying and/or cooling the film to physically immobilize its gradient. Unfortunately, this preservation was temporary, and underwent degradation over time. Our work is aimed to overcome this limitation by covalently attaching counterions to the polymer backbone and thus permanently locking the redox gradients. Both parts of this dissertation utilize heteroleptic metal complexes possessing redox potentials close to zero (vs SSCE). Compounds with highly negative potentials are strongly reducing and highly positive potentials means strong oxidizing capabilities, which exerts strict requirements on supporting electrolytes and solvents, including high impurity, broad potential window as well as exclusion of environmental interference. Thus, the closer the potential to zero (vs SSCE), the more stable (electrochemically) the complex and the easier the electrochemical measurements.
Open Access
African-American women college and university presidents: their role, experiences, challenges and barriers
(Colorado State University. Libraries, 2008) Woodard, Sophia J., author; Davies, Timothy G., advisor
The purpose of this study was to examine four phenomena: role, experiences, challenges, and barriers of African-American women college and university presidents with a particular focus on the role based on the social conscious concept of "race upliftment" as espoused by Dr. W.E.B. DuBois and other African American scholars of the early 20th century. The review of literature suggests that there is a tendency to advocate for race upliftment primarily when leading an African-American institution or an Historically Black College and University (HBCU). As a qualitative phenomenological study, in-depth personal and telephone one to two hour interviews were conducted with eight African-American women college and university presidents of two and four-year institutions. Each interview was tape-recorded with the full permission of the president. A demographic questionnaire was completed by each president prior to conducting the interview. All eight recorded tapes were transcribed and the data analysis process involved six major steps based on Creswell (1994). The qualitative software HyperRESEARCH was used to assist in analyzing and coding the data, and in compiling the qualitative report. Reading and memoing were used for code and theme development, and a reflexive journal, member checking, clarifying research bias and peer review were used for validity and trustworthiness. The findings of this study revealed that role plays a significant component for these women and is categorized into several areas that include: (1) nurturer and protector of students; (2) fiscal manager; (3) values and skills practitioner; (4) spiritual practitioner and servant; and (5) communications expert. Their work in role directly impacts and influences how they view and serve in their role as leaders. In fact, these African-American women college and university presidents developed many of their concepts of role based on the multi-faceted experiences they encountered both on their journey to the presidency and in this journey. Many of their experiences encompassed their formative years of education and training/rearing in their homes and communities, the educational journeys they traveled through college and graduate school, as well as the varied professional encounters in academia prior to becoming presidents. The collective energy of these experiences were an exciting and foundational part of their leadership development and journeys to the presidency which were also consumed with challenges and barriers. These challenges and barriers were centered around five specific areas that comprised the challenges of leadership: (1) addressing and resolving fiscal insolvency; (2) personal challenges such as parenting roles and living apart from family members(children and husbands); (3) managing health and wellness; (4) gender, race and age disparity; and (5) professional challenges such as status quo issues, college-wide communication issues, dealing with alumni concerns and problems with overbearing board-of-trustee members. In essence, the role, experiences, challenges and barriers that emerged from the data (voices) of these African-American women college and university presidents comprise the journey they traveled in becoming and being president.