This research examined how the North Carolina A & T State University Cooperative Extension program has helped limited-resource farmers realize economic, environmental, and social outcomes through its 1890 Extension education program. Since1990, there has been little research on recent contributions of 1890 Extension programs for this audience. This inquiry described educational collaborative efforts among the North Carolina A & T Extension program, North Carolina State University (NCSU), other 1862 land-grant universities, community-based organizations, and government agencies providing nonformal education and services to limited-resource farmers. Personal interviews were conducted with two Extension specialists, one associate, two agents, and two agricultural and natural resource technicians. A focus group was conducted with nine limited-resource farmers.The findings revealed that the Farmers Adopting Computer Training (FACT), Plasticulture, and Pastured-Swine programs have helped enhance limited-resource farmers' economic, environmental, and social outcomes. In addition, the participants confirmed caring, trust, and relationship building as qualities that encouraged their participation. However, participants indicated that scheduling Extension programs that conflict with planting and harvesting season and programs that do not address farmers' needs and issues prevent their participation in Extension programs. Furthermore, North Carolina A & T Extension programs involved farmers in program planning through advisory committees and mentoring other farmers. Participants indicated that NC A & T collaborates with North Carolina State University, community-based organizations, and other government agencies to meet the needs of limited-resource farmers.The data suggest that the following improvements and changes for the North Carolina A & T Extension program: (a) use the outcome-based evaluation approach to evaluate Extension programs, (b) provide training for Extension faculty on program planning models, (c) continue the FACT, plasticulture, and pastured-swine production programs, (d) educate faculty in other schools and colleges at NC A & T State University about Extension programs, and (e) develop joint programs with other schools and colleges at North Carolina A & T State University. / Ph. D.

The purpose of this study was to collect exploratory data on dietary acculturation, physical activity, and body image in a limited resource Latina population in northern Virginia. Acculturation may be described as a process in which members of one cultural group adopt the beliefs and behaviors of another group. Acculturation has been associated with a variety changes in terms of diet, physical activity and body image. Most dietary acculturation research in the U.S. has focused on Mexican Americans, Cuban Americans, and Puerto Ricans; however this study was composed of mostly Central and South Americans. Eighty-five subjects were recruited from the Arlington County Expanded Food and Nutrition Education Program, Arlington County Women, Infants, and Children program, and the Fairfax County Parklawn Family Center. Demographic information, acculturation, fruit and vegetable intake, saturated fat avoidance, physical activity, and body image were assessed with written survey instruments. The results indicated that this Latina population with limited resources in northern Virginia was mainly from Bolivia and El Salvador, and was not highly acculturated. Almost half of the participants were overweight or obese. About 50% of the population met the 5-A-Day goal for fruit and vegetable intake and almost 95% of participants exhibited at least one form of saturated fat avoidance. Eighty-five percent of the population reported participating in 30 minutes or more leisure-time physical activity less than 3 times each week, though a similar percentage reported that physical activity was important for health. Sixty percent of respondents were on a weight loss diet. While there was a significant relationship between the number of servings of fruit consumed and acculturation, there was no significant relationship between acculturation and any other dietary, physical activity or body image factor measured. The results of this study provide a baseline for further research in the limited resource Latina population in northern Virginia. / Master of Science

The strength model of self-control predicts that when people exert self-control, they should show performance decrements on subsequent self-control tasks. However, it is possible that this pattern of behaviour is confined to specific experimental procedures, which amplifies the effect. The aims of this thesis are to; 1) test the strength model predictions in sport; and 2) examine emotion as a mediator of self-control performance effects. Study 1 consisted of two experiments. Experiment 1 set out to demonstrate a pattern of resource depletion. Forty-three sport and exercise students performed either an incongruent (self-control depletion) or congruent (control) Stroop task before and after performing a virtual reality cycling task on an indoor cycling ergometer. Findings showed the depletion group performed worse on the second Stroop task than on their first task or than the control group. Experiment 2 sought to address some of the methodological concerns in Experiment 1, and examine emotion as a factor explaining performance. Forty-eight physically active participants followed the same experimental protocol, but with an additional iteration of both tasks. Results demonstrated that both cycling and Stroop task performance improved across time. In addition, participants reported feeling happier and more motivated during the second cycling task. Study 2 provided a conceptual replication of Study 1, using different tests of self-control. Twenty-six university-level male soccer players either performed the Loughborough Soccer Passing Test (LSPT) with (self-control depletion) or without (control) an audio file simulating crowd noise, and then performed the wall squat muscle endurance test. The self-control depletion group reported feeling more anxious during the LSPT and performed worse than the controls on the wall squat. III Next, in Study 3, nineteen well-trained competitive endurance runners performed a self-paced 1600 m running trial and then ran a second trial either self-paced or with a pacemaker. The pacemaker had no significant effect on actual performance time but participants reported feeling more anxious beforehand and adopted a fast start strategy, whereas the self-paced group had a conservative pacing pattern. Study 4 showed that, for females, consuming a sports drink—as opposed to plain water—associated with better physical (high-intensity track running) and cognitive self-control (Stroop) performance. In addition, they appeared to be happier drinking water, and more anxious drinking the sports drink—an effect that diverged over the six weeks. Study 5 examined the effects of three strategies—designed to increase or decrease the intensity of emotions—on emotion, pacing strategy and 1600 m performance. Results showed the intervention designed to decrease unpleasant emotions was associated with lower anxiety, higher calmness, a slower first 400 m, and more overall consistent pacing strategy. Study 6 examined the effects of imagery training on swimming tumble-turn performance. Findings showed no significant intervention effect, a result that goes against the proposed benefits of psychological skills training and runs counter to the predictions of the strength model. Collectively, the evidence in the thesis provides limited support for the strength model. It is concluded that self-control performance does not inevitably deteriorate across self-control tasks where the individual is well-versed with the task demands, or where tasks are not physically strenuous enough to tax mental resources. In contrast, the explanation for performance deterioration across a series of novel tasks is likely to extend beyond that of a self-control resources perspective. Future research might profitably test this proposal.

The aims of this research work are to develop a feature detection, description, and matching system for low-resource applications. This work was motivated by the need for a vision sensor to assist the flight of a quad-rotor UAV. This application presented a real-world challenge of autonomous drift stabilization using vision sensors. The initial solution implemented a basic feature detector and matching system on an FPGA. The research then pursued ways to improve the vision system. Research began with color feature detection, and the Color Difference of Gaussians feature detector was developed. CDoG provides better results than gray scale DoG and does not require any additional processing than gray scale if implemented in a parallel architecture. The CDoG Scale-Invariant Feature Transform modification was developed which provided color feature detection and description to the gray scale SIFT descriptor. To demonstrate the benefits of color information, the CDSIFT algorithm was applied to a real application: library book inventory. While color provides added benefit to the CDSIFT descriptor, CDSIFT descriptors are still computationally intractable for a low-resource hardware implementation. Because of these shortcomings, this research focused on developing a new feature descriptor. The BAsis Sparse-coding Inspired Similarity (BASIS) descriptor was developed with low-resource systems in mind. BASIS utilizes sparse coding to provide a generic description of feature characterstics. The BASIS descriptor provided improved accuracy over SIFT, and similar accuracy to SURF on the task of aerial UAV frame-to-frame feature matching. However, basis dictionaries are non-orthogonal and can contain redundant information. In addition to a feature descriptor, an FPGA-based feature correlation (or matching) system needed to be developed. TreeBASIS was developed to answer this need and address the redundancy issues of BASIS. TreeBASIS utilizes a vocabulary tree to drastically reduce descriptor computation time and descriptor size. TreeBASIS also obtains a higher level of accuracy than SIFT, SURF, and BASIS on the UAV aerial imagery task. Both BASIS and TreeBASIS were implemented in VHDL and are well suited for low-resource FPGA applications. TreeBASIS provides a complete feature detection, description, and correlation system-on-a-chip for low-resource FPGA vision systems.

We conduct an evaluation of the cross-cultural ‘export’ of the Objective Structured Clinical Examination (OSCE), a well-established Western medical education assessment tool that is in keeping with Competency-Based Medical Education (CBME) principles, into the new socio-economic setting of Rwanda. The evaluation framework of ‘assessment utility’ is applied, where the utility of an assessment is described conceptually as the multiplicative function of its validity (V), reliability (R), educational impact (E), cost/feasibility (C) and acceptability (A). A mixed-methods approach of both quantitative and qualitative data analysis is used. The quantitative findings support high content and face validity, high reliability, high acceptability and achievable cost and feasibility of the OSCE, all of which would suggest high utility. The analysis of qualitative data identifies some important threats to validity, namely perceived significant gaps in training in the internship program that were thought to likely be the underlying reason for the low mean assessment scores. This threat to the validity of the results appears to influence and limit the acceptability of the assessment in this context. While it is believed that it would be suitable as a formative assessment, primarily for the purpose of ‘assessment for learning’, it was not felt that it was currently acceptable as a summative or high-stakes ‘assessment of learning’, until and unless training deficits are addressed. Currently, the OSCE is seen to have greatest value in its potential for educational impact by acting as both a driver and a marker for change both at the individual and programmatic levels. Many principles of CBME and the concept of ‘entrustability’ as a criterion-referenced assessment standard were well-received cross-culturally, when training and assessment were viewed in tandem. Our study highlights the importance of using a comprehensive evaluation framework that includes both quantitative and qualitative methods to accurately characterize the utility of an assessment. / Thesis / Master of Science (MSc) / This is a case-study where the Objective Structured Clinical Examination (OSCE), a well-established, performance-based and resource-intensive Western medical education assessment tool, was introduced to the culturally different, resource-limited setting of Rwanda. What we wanted to evaluate is how the OSCE was received in the Rwandan medical training system. What we found is that generally, the OSCE was received in a positive way. Both examiners and participants thought it was a relevant, realistic, feasible, valuable test for doctors in training. However, examiners also felt that the candidates did not do as well as they could have on the test not because they were fundamentally bad doctors, but because there were major gaps in their training. The OSCE therefore demonstrated its usefulness by identifying these deficiencies in training. Examiners felt that addressing these gaps in training was most important and should be done before any institutional body uses the OSCE results to decide who should get a medical license or not.

O Reservatório de Itupararanga, no interior do estado de São Paulo, tem como principal finalidade geração de energia elétrica e o abastecimento público, além de área de lazer e pesca. O crescimento urbano e agrícola em torno do corpo hídrico tem alterado a qualidade da água favorecendo a proliferação de cianobactérias. Estudos preliminares da comunidade fitoplanctônica demonstraram a dominância da cianofícea Cylindrospermopsis raciborskii e da clorofícea Monoraphidium contortum. Com o objetivo de investigar o nível trófico do reservatório e sua influência na dominância destas espécies, foram realizados ensaios de interação entre estes microrganismos sob diferentes concentrações de fósforo, simulando o reservatório em três diferentes níveis tróficos: oligotrófico, mesotrófico e supereutrófico. Também foi determinada a produção de saxitoxina pela cianobactéria. No ambiente oligotrófico a C. raciborskii apresentou diminuição do volume celular, aumento da produção de saxitoxina e senescência em interação com o M. contortum. Nos ambientes mesotrófico e supereutrófico, a cianobactéria não apresentou diferenças no crescimento e na produção de saxitoxina, comparado ao seu controle, quando em interação com a clorofícea. O mesmo não foi observado para M. contortum nestes dois níveis de trofia, pois teve seu crescimento prejudicado nas interações com C. raciborskii. As velocidades específicas de crescimento de M. contortum foram crescentes conforme o aumento da trofia, e as da C. raciborskii decrescentes. As concentrações de clorofila-a também foram crescentes conforme o aumento de trofia, e diminuíram no final dos experimentos. O consumo de ortofosfato foi semelhante na simulação dos três ambientes e o consumo do nitrato, foi maior quanto mais elevado o nível trófico. A partir dos resultados, foram feitas previsões das espécies fitoplanctônicas dominantes regidas pelo nível trófico do reservatório, que contribuirão nas medidas de conservação e manejo deste ecossistema aquático. / The Reservoir Itupararanga within the state of São Paulo, whose main purpose is public supply, besides electricity generation, and recreational areas and fishing. The urban growth and agriculture around the water body has changed its quality, favoring the growth of cyanobacteria. Preliminary studies of phytoplankton showed a dominance of cyanophyceae Cylindrospermopsis raciborskii and clorofícea Monoraphidium contortum. In order to investigate the trophic level of the reservoir and its influence on the dominance of these species, tests of the interaction between these microorganisms under different phosphorus concentrations were performed, simulating the reservoir in three different trophic levels: oligotrophic, mesotrophic and supereutrophic. The production of saxitoxin by the cyanobacteria was also defined. In the oligotrophic C. raciborskii showed a decrease of cell volume, increased production of saxitoxin and senescence in interaction with M. contortum. In mesotrophic and supereutrofic environments, the cyanobacteria did not show differences in growth and production of saxitoxin, compared to their control when interacting with the chlorophycea. The same was not observed for M. contortum in these two trophic levels, as its growth was affected by the interactions with C. raciborskii. The specific growth rates of M. contortum were growing with increasing trophic, and those of C. raciborskii decreasing. The chlorophyll-a concentrations were also growing with increasing trophic, and decreased at the end of the experiments. The orthophosphate consumption was similar in the three simulation environments and consumption of nitrate was greater the higher the trophic level. From the results, were made estimates of the dominant phytoplankton species was governed by the trophic level of the reservoir, which will help in the conservation and management of this aquatic ecosystem.

O Reservatório de Itupararanga, no interior do estado de São Paulo, tem como principal finalidade geração de energia elétrica e o abastecimento público, além de área de lazer e pesca. O crescimento urbano e agrícola em torno do corpo hídrico tem alterado a qualidade da água favorecendo a proliferação de cianobactérias. Estudos preliminares da comunidade fitoplanctônica demonstraram a dominância da cianofícea Cylindrospermopsis raciborskii e da clorofícea Monoraphidium contortum. Com o objetivo de investigar o nível trófico do reservatório e sua influência na dominância destas espécies, foram realizados ensaios de interação entre estes microrganismos sob diferentes concentrações de fósforo, simulando o reservatório em três diferentes níveis tróficos: oligotrófico, mesotrófico e supereutrófico. Também foi determinada a produção de saxitoxina pela cianobactéria. No ambiente oligotrófico a C. raciborskii apresentou diminuição do volume celular, aumento da produção de saxitoxina e senescência em interação com o M. contortum. Nos ambientes mesotrófico e supereutrófico, a cianobactéria não apresentou diferenças no crescimento e na produção de saxitoxina, comparado ao seu controle, quando em interação com a clorofícea. O mesmo não foi observado para M. contortum nestes dois níveis de trofia, pois teve seu crescimento prejudicado nas interações com C. raciborskii. As velocidades específicas de crescimento de M. contortum foram crescentes conforme o aumento da trofia, e as da C. raciborskii decrescentes. As concentrações de clorofila-a também foram crescentes conforme o aumento de trofia, e diminuíram no final dos experimentos. O consumo de ortofosfato foi semelhante na simulação dos três ambientes e o consumo do nitrato, foi maior quanto mais elevado o nível trófico. A partir dos resultados, foram feitas previsões das espécies fitoplanctônicas dominantes regidas pelo nível trófico do reservatório, que contribuirão nas medidas de conservação e manejo deste ecossistema aquático. / The Reservoir Itupararanga within the state of São Paulo, whose main purpose is public supply, besides electricity generation, and recreational areas and fishing. The urban growth and agriculture around the water body has changed its quality, favoring the growth of cyanobacteria. Preliminary studies of phytoplankton showed a dominance of cyanophyceae Cylindrospermopsis raciborskii and clorofícea Monoraphidium contortum. In order to investigate the trophic level of the reservoir and its influence on the dominance of these species, tests of the interaction between these microorganisms under different phosphorus concentrations were performed, simulating the reservoir in three different trophic levels: oligotrophic, mesotrophic and supereutrophic. The production of saxitoxin by the cyanobacteria was also defined. In the oligotrophic C. raciborskii showed a decrease of cell volume, increased production of saxitoxin and senescence in interaction with M. contortum. In mesotrophic and supereutrofic environments, the cyanobacteria did not show differences in growth and production of saxitoxin, compared to their control when interacting with the chlorophycea. The same was not observed for M. contortum in these two trophic levels, as its growth was affected by the interactions with C. raciborskii. The specific growth rates of M. contortum were growing with increasing trophic, and those of C. raciborskii decreasing. The chlorophyll-a concentrations were also growing with increasing trophic, and decreased at the end of the experiments. The orthophosphate consumption was similar in the three simulation environments and consumption of nitrate was greater the higher the trophic level. From the results, were made estimates of the dominant phytoplankton species was governed by the trophic level of the reservoir, which will help in the conservation and management of this aquatic ecosystem.

Master of Public Health / Department of Human Nutrition / Mary L. Higgins / Nutrition education programs strive to help low-income people make optimal food choices while living on a limited budget. This study addressed perceived understanding, acceptance, and usability of Food and Nutrition Bytes, a set of 12 eight- to eleven-minute online Expanded Food and Nutrition Education Program (EFNEP) lessons. Clients in EFNEP during 2005-2006 were surveyed on internet usage and interest in online nutrition lessons. Lessons were developed and assessed for reading levels using two formulas. Clients and professionals in six Kansas counties completed a Likert scale survey and gave comments after they viewed one online lesson. Fifty-five percent of 75 EFNEP clients who had internet access indicated they were interested in taking nutrition lessons online. The new lessons averaged a 6.64 grade reading level. Two lessons had content that was rated too general to be useful. For the remaining lessons, both groups ranked their perceived understanding, helpfulness of graphics and audio, and usefulness of information at the first or second most-desirable rating. They rated length and amount of information as “Just Right.” The only difference found between the groups was when clients rated one lesson as having a little too much information and professionals rated it as having not quite enough (Mann-Whitney U = 35.0, p = 0.039). Within-sample associations were measured for two lessons. Clients older than 30 years of age found the Grains lesson’s pictures and graphics to be more helpful than did younger clients (Kendall tau-b = 0.593, p = 0.002). White clients evaluated the Cooking lesson as being easier to understand than did non-white clients (Kendall tau-b = -0.477, p = 0.020). The most frequent comments pertained to the importance of portion sizes and appropriate pictures and graphics. Overall, Food and Nutrition Bytes lessons were easy to read, and perceived by both clients and professionals to be easy to understand, helpful and useful, and also optimal in length and amount of information. Despite low numbers of EFNEP clients who had internet access, over half were interested in taking lessons online. Limitations of this study include small samples, convenience samples, subjects’ time constraints, and interviewer bias.

This research has been conducted in order to create a robust, lightweight feature detecting and matching algorithm that builds upon the foundation set by the TreeBASIS algorithm. The goal is to create a color-based version of the TreeBASIS algorithm that uses less hardware resources than the original, is more accurate in its matching capabilities, can successfully be deployed on a resource-limited FPGA platform, and can process in real time. This thesis first presents the newly designed hardware tri-channel FAST Feature Detector that finds features in color. Next the TreeBASIS algorithm is analyzed to discover what improvements can be made in order to reduce its resource usage sufficiently to be able to run on the Xilinx Virtex-4 FX60 while processing color features. At the same time, a software version of the Color TreeBASIS algorithm is compared to the original algorithm and is found to have a 93.3% accuracy on a test set of aerial images, surpassing the accuracy of TreeBASIS by nearly 12%. Then the hardware is meticulously reviewed to discover even more optimizations that allow the Color TreeBASIS algorithm to easily fit onto the Virtex-4 FX60. Next a new application for the matching algorithm, object detection, is introduced as well as the hardware needed to support it. Finally the algorithm is tested on the FPGA system for object detection and is able to successfully identify objects at 60 FPS. Color TreeBASIS proves itself to be more accurate than the TreeBASIS algorithm in the aerial images tests, it ends up using less memory and logic resources than its predecessor, even though it processes three times as much data, it is successfully deployed on a resource-limited FPGA system, and it shows accurate results in real-time object identification, generating an accurate homography 20 to 45% of the time while processing matches at a rate of 60 FPS.

In the United States (U.S.), up to 40% of the entire food supply is lost or wasted, which contributes to negative environmental, economic, and social outcomes, with the majority of food waste occurring in the retail and consumer sectors of the food supply chain. Concurrently, 10.5% of U.S. households experienced food insecurity in 2019. Food insecurity rates are higher among individuals with low income and disproportionately affects ethically and racially diverse people living in poverty. Diverting excess food from retail and institutional settings to people in need is one method to reduce food waste and enhance individual, household, and community food security. This PhD dissertation describes four studies that explored food waste management in the U.S. among households with low-income and within U.S. food pantries, which are a critical component of the emergency food system. Study 1 consisted of a systematic review that examined differences in food waste attitudes and practices among consumers of across income levels. Study 2 was a quantitative research methods approach to examine food waste attitudes and practices of SNAP-eligible households (n=17). Study 3 was a cross-sectional quantitative approach to examine the impact of the novel coronavirus disease (COVID-19) pandemic on food waste management within U.S. food pantries (n=290). Study 4 assessed the feasibility of food pantries in Virginia (n=68) to implement marketing-mix and choice-architecture (MMCA) strategies within their food pantries given the changes they had to make in their food distribution models in response to COVID-19 physical distancing requirements. Collectively, the studies described in this PhD dissertation address knowledge gaps and may be used to inform policies and initiatives to increase food security and decrease food waste among households with low-income and organizations aimed at serving them. / Doctor of Philosophy / Food waste in the U.S. is a major challenge that impacts the environment, economy, and society. The largest amounts of food waste are generated within food retail and consumer household settings. Concurrently, food insecurity, which is defined as obtaining and having access to enough food for an adequate, nutritious diet, is also another complex food systems challenge in the U.S. Food insecurity rates are higher among people with low income and disproportionately affects ethnically and racially diverse people. The novel coronavirus (COVID-19) pandemic placed further pressure on these two food systems challenges. Diverting excess, wholesome food from retail and institutional settings to people with hunger is a preferred method to mitigate both food waste levels and food insecurity rates. The U.S. emergency food system, which is a network of food recovery organizations that aim to receive excess food from retail settings and redistribute the food to people with hunger, play a pivotal role in addressing these two challenges. This PhD dissertation described four studies that address these two challenges. While this dissertation examined food waste management, the first half of the dissertation explored this topic within households and the second half explored food waste management within food pantries, which are a critical component to the U.S. emergency food system. Study 1 utilized a systematic procedure to review previously published consumer food waste research. The purpose of this study was to examine differences in food waste attitudes and practices among consumers of various income levels. Study 2 used a survey to examine food waste attitudes and practices of households eligible for Supplemental Nutrition Assistance Program (SNAP) benefits. Study 3 explored the impact of COVID-19 physical distancing requirements on food waste management within U.S. food pantries. Lastly, study 4 explored the feasibility of food pantry staff/volunteers on implementing behavioral economics strategies, which are changes to a setting that can promote selection of a certain food item, within their food pantry. Collectively, the studies described in this PhD dissertation address knowledge gaps and may inform policies and initiatives to mutually increase food security and decrease food waste among households with low-income and organizations aimed at serving them.