The purpose of this study was to identify the barriers Virginia agricultural producers encounter when using the Internet and their preferences when seeking information delivered via the Internet. The results are expected to provide Extension educators needed information about producer Internet use patterns and their preferences related to Internet-based learning systems. The survey population (N = 370) consisted of Virginia agricultural producers currently known to be using the Internet as identified by the county Agricultural Extension agents. Data were collected online via an interactive, encrypted Web site and analyzed with SAS/STAT software. The 186 usable producer responses indicated that they were predominately white (98.36%), males (82.87%) averaging 51 years of age with some college education. Their primary occupation was farm or ranch work (41.71%) with a gross value of agricultural sales of $100,000 - $249,999. Nearly 60% conducted Internet agricultural marketing activities; three quarters purchased agricultural supplies, 43.17% conduct non-agricultural Internet business, and 50% use dialup services to access the Internet. In total, 95.68% of the responding producers access the Internet at least once a week and 31.60% reported previous participation in Internet-based learning. Producers below 30 years of age considered their lack of experience/training to be less of a barrier than older producers. Time constraints associated with job responsibilities, isolation from other program participants, and their ability to learn at a distance were seen as greater barriers by males than females. Producers listing their primary occupation as other than farming saw time constraints associated with their job as a greater barrier than those retired but still farming. Producers with a high school education generally rated barriers associated with Internet-based learning as greater obstacles than those with advanced degrees. Following an exposure to an Internet-based learning experience, no differences were observed related to the producers' age, gender, primary occupation, and the operation's gross value of agricultural sales and the selected factors. Producers making agricultural Internet purchases, perceived their motivation to participate in Internet-base learning as less of a barrier than those that did not. Generally, as the producers' Internet use frequency increased, their perception of the barriers was reduced and those with previous Internet-based learning experience saw their ability to learn at a distance as less of a barrier than did those with no experience. A comparison of pre- and post-exposure data, revealed time constrains associated with job responsibilities, access to instructors/specialists, feedback/instructor contact, and the motivation to participate as the greatest barriers to Internet-base learning. Differences in pre- and post-exposure assessments confirm that producers' perception of the barriers were worse than actuality. Extension's Internet-based learning experiences should be accessible from a familiar Internet location. The learners' abilities and connectivity should be considered when developing systems to minimize barriers associated with these factors. Internet-based activities should be relevant to the learner. Experiences should be available in multiple formats including video, audio, print and combinations of the aforementioned. Learners should be afforded the opportunity to interact with the presenter/instructor via the most acceptable and timely means. / Ph. D.

Autism spectrum disorder (ASD) is associated with a variety of physical, mental, and behavioral healthcare needs. However, parents of autistic children consistently report difficulty accessing necessary services, and no instrument has been validated to assess and quantify these barriers for autistic children. The current study aims to adapt and validate the Barriers to Care Questionnaire (BCQ), a pre-existing measure of barriers to healthcare for children with specific healthcare needs, for families of autistic children. The BCQ and theoretically related measures were collected from 242 parents (117 parents of autistic children, 125 parents of non-autistic children). Cronbach’s alpha statistics (ranging from 0.87 to 0.96 for BCQ subscales) provide evidence of reliability for the BCQ. The BCQ subscales were correlated with unmet treatment need, treatment experiences, and theoretically related variables at the child, parent, and family level, providing evidence of convergent validity. Correlations were of low magnitude with theoretically unrelated variables (parent personality and socially desirable responding), suggesting preliminary evidence of discriminant validity. Additionally, the BCQ subscales predicted a significant amount of variance in unmet need and treatment experiences over and above other predictors for autistic youth, indicating incremental validity. Parents of autistic children reported significantly more barriers to care across all subscales of the BCQ than parents of non-autistic children, and the highest average item score was on the “skills” subscale, which measures difficulties with navigating the healthcare system. Results support that the BCQ can be used among autistic youth, and suggest the critical need for family-centered supports and provider education in order to ameliorate barriers to healthcare for autistic children. / M.S. / Autism spectrum disorder (ASD) is related to many physical, mental, and behavioral healthcare needs. However, parents of autistic children state that it is often hard to receive healthcare when their child needs it. No questionnaire exists to measure barriers that make getting healthcare harder for autistic children. Our study adapted the Barriers to Care Questionnaire (BCQ) for families of autistic children. The BCQ and related questionnaires were filled out by 242 parents (117 parents of autistic children, 125 parents of non-autistic children). The BCQ reliably and consistently measured barriers to care in these groups. The BCQ subscales were associated with unmet treatment need, treatment experiences, and other related variables at the child, parent, and family level. The questionnaire was less strongly related to variables that we would not expect to be associated with barriers to care, like personality and social desirability. Also, the BCQ subscales predicted healthcare experiences even when accounting for other factors that might impact access to care. Parents of autistic children reported more barriers to care on all subscales of the BCQ than parents of non-autistic children, and the highest average item score was on the “skills” subscale, which measures difficulties with navigating the healthcare system. Results show that the BCQ can be used among autistic youth, and suggest the need for family-centered supports and provider education in order to improve barriers to healthcare for autistic children.

Data from seven work sites that had purchased a commercial weight loss program for their employees was used to determine (a) the most prevalently identified barriers and motives for weight loss, (b) the relationship between barrier identification and subsequent attrition at 3 and 6 months post program initiation, (c) the relationship between motive identification and subsequent attrition at 3 and 6 months, (d) the relationship between barrier identification on weight loss at 3 and 6 months, (e) the relationship between motive identification on weight loss at 3 and 6 months, (f) the effectiveness of the program at the end of three and six months of participation (g) the reach of the program into the eligible employee population, and (h) the proportion of the targeted employee population that ultimately benefited from the program and the degree to which they benefited (i.e., effectiveness that accounts for reach and retention). The most frequently selected barriers were being stressed, having too many opportunities to eat unhealthy foods, and a lack of time to exercise. The most frequently selected motives were to look better, a sense of it being the "right time", and to improve health. Chi square test revealed that those participants who selected a given barrier or motive were more likely to be retained than those who did not select a given barrier at the beginning of the program. When we controlled for age and gender, we found that women who selected motives at the beginning of the program were more likely to be retained on this program than men. Age of the participants did not influence their retention on the program. Logistic regression analysis when controlling for gender & age indicated that women and older adults were somewhat more likely to be retained on the program at both 3 and 6 months of participation. Multivariate regression analysis indicated that there was no significant association between selection of total motivators and barriers and weight loss at 3 & 6 months of participation. Intention to treat analyses using baseline value carried forward for participants lost to attrition revealed that participants lost a significant (p<.01), yet modest, 2.1 lbs of weight at 3 and 2.5 lbs of weight at 6 months of participation. Follow-up analyses were conducted to determine the overall proportion of the workforce that benefited (i.e., lost weight) at 6 months. Of the 1607 participants who were retained at 6 months 1088 were successful in losing weight and lost, on average 9.4 pounds (95% CI: 8.8 to 9.9 pounds), a clinically significant 4.4% of initial body weight. Thus, 10.1% of the total employee population benefited from the weight loss program and lost a clinically relevant amount of weight. The findings of this study indicate that information on motives and barriers most frequently identified by the participants can be used to customize weight loss programs in order to enhance retention of its participants. Also presenting reach by effectiveness data to the employers could help them in making more sophisticated decisions while choosing a commercial weight loss program for their employees. / Master of Science

Yes / Optimising the use of patient data has the potential to produce a transformational change in healthcare planning, treatment, condition prevention and understanding disease progression. Establishing how people's trust could be secured and a social licence to share data could be achieved is of paramount importance. The study took place across Yorkshire and the Humber, in the North of the England, using a sequential mixed methods approach comprising focus groups, surveys and co-design groups. Twelve focus groups explored people's response to how their health and social care data is, could, and should be used. A survey examined who should be able to see health and care records, acceptable uses of anonymous health and care records, and trust in different organisations. Case study cards addressed willingness for data to be used for different purposes. Co-creation workshops produced a set of guidelines for how data should be used. Focus group participants (n = 80) supported sharing health and care data for direct care and were surprised that this is not already happening. They discussed concerns about the currency and accuracy of their records and possible stigma associated with certain diagnoses, such as mental health conditions. They were less supportive of social care access to their records. They discussed three main concerns about their data being used for research or service planning: being identified; security limitations; and the potential rationing of care on the basis of information in their record such as their lifestyle choices. Survey respondents (n = 1031) agreed that their GP (98 %) and hospital doctors and nurses (93 %) should be able to see their health and care records. There was more limited support for pharmacists (37 %), care staff (36 %), social workers (24 %) and researchers (24 %). Respondents thought their health and social care records should be used to help plan services (88 %), to help people stay healthy (67 %), to help find cures for diseases (67 %), for research for the public good (58 %), but only 16 % for commercial research. Co-creation groups developed a set of principles for a social licence for data sharing based around good governance, effective processes, the type of organisation, and the ability to opt in and out. People support their data being shared for a range of purposes and co-designed a set of principles that would secure their trust and consent to data sharing. / This work was supported by Humber Teaching NHS Foundation Trust and the National Institute for Health Research (NIHR) Yorkshire and Humber Patient Safety Translational Research Centre (NIHR Yorkshire and Humber PSTRC).

Barriers to fish movement can cause aquatic habitat fragmentation by reducing the amount of available habitat. The primary goal of my research was to investigate applications of population genetic analysis tools as indicators of barrier effects on brook trout populations in fragmented subwatersheds. In chapter1, I tested the hypothesis that brook trout population genetic differentiation (FST) above and below barriers will differ in relation to barrier height and gradient. I also tested the hypothesis that average gene diversity per locus (H) and the numbers of alleles (A) differed between samples below and above each barrier. There was no significant difference in average number of alleles (A) or average gene diversity per locus (H) between the above- and below-barrier samples, but linear regression identified a statistically significant relationship between barrier height and FST values. Unrooted neighbor-joining consensus trees of Cavalli-Sforza and Edwards (1967) chord distances provided evidence of genetic differentiation between samples of resident brook trout above and below natural barriers. Additionally, average total allelic diversity (A), average gene diversity per locus (H), average number of private alleles per locus per sample, and total alleles per sample differed between Level III Ecoregions. In chapter 2 I tested the hypothesis that the presence of a barrier, total habitat potentially isolated above a barrier (km), road density, and percent forest cover within a subwatershed (USGS 6th-level Hydrologic Units) were significant habitat fragmentation factors affecting the effective population size (Ne) of brook trout in the Blue Ridge Level III Ecoregion. Multivariable linear regression indicated that total habitat above the barrier (km) and road density were significant variables retained in the model to predict Ne. In chapter 3, the objective of the study was to infer relationships between barriers and family structure in brook trout populations. Maximum likelihood analysis of pairwise kinship relationships between above- and below-barrier individuals indicated the presence of parent-offspring relationships between above- and below-barrier individuals at six sites in the Blue Ridge Level III Ecoregion and five sites in the Northern Lakes and Forests Level III Ecoregion, which indicated movement of individuals between the above- and below-barrier locations. / Ph. D.

Thirty-two Antiguan women from a women's church group attended participatory group meetings to describe their priority health definitions, perceived health barriers, preferred health barrier solutions, and body size preferences and perceptions. Participants were 21-70 years old, and were divided into three age groups. Although 70% of the sample were either overweight or obese, weight issues received little priority as a health related factor. Instead, women under 30 defined health more in terms of personal appearance, and dietary inadequacy from lack of resources, with priority for mental and social health barriers, while those in their 30's were mainly concerned about barriers related to their mental and social well-being, and those ~ 40 years gave priority to dietary inadequacy and inactivity barriers related to chronic and general health factors. Although self-curing barrier solutions were most preferred~ religious and medical solutions were perceived as easier to attain. Using silhouettes, women under 30 frequently chose thinner ideals than those over 30, and perceived themselves as heavier than anthropometric measurements indicated, while those ≥40 years perceived themselves as lighter. / Master of Science

A coefficient sensitivity measure for state space recursive, finite wordlength, digital filters is developed and its relationship to the filter output quantization noise power is derived. The sensitivity measure is simply the sum of the L₂ norm of all first order partials of the system function with respect to the system parameters; alternatively, the measure may be viewed as the output variance of the error system created by the inherent parameter quantization. Since the measure uses only the first order partials, it is a lower bound approximation to the output quantization noise power. During analysis, numerically unstable conditions may occur because ideal filter characteristics imply system poles which are almost on the unit circle in the z-plane; therefore, it is proposed to scale the radii of the pole and zero magnitudes. Thus, the scaled system has the same frequency information as the original system, but performs better numerically. The direct II form sensitivity, which is shown to be inversely proportional to the product of the system pole and zero distances, can be reduced by the judicious placement of added pole/zero cancellation pairs which increase the order of the system but do not change the system function. / M. Eng.

The literature on minority student achievement indicates that Black students are underrepresented in advanced mathematics courses. Advanced mathematics courses offer students the opportunity to engage with challenging curricula, experience rigorous instruction, and interact with quality teachers. The middle school years are particularly significant for mathematics education since the courses students pursue during those years affect later access to rigorous mathematics coursework at the high school level as well as college and career readiness. This case study examined factors that affected Black student achievement in advanced mathematics classes at one middle school. Data included interviews of school personnel, on-site observations, and school-related document analysis. Six major themes that affected student achievement in advanced mathematics classes emerged from the data: (a) mathematics placement innovations, (b) cultural shift towards increased rigor, (c) culture of high expectations, (d) culture of continuous learning, (e) data sharing, and (f) perceived barriers to enrollment. The conceptual framework of Bryk, Sebring, Allensworth, Luppescu, and Easton (2010) was used to identify and explain the relationships among these categories. This case study highlighted key district and school individuals who initiated and implemented the wave of changes regarding mathematics placement and teaching that occurred over a four-year period. The study also identified barriers that seemed to impede Black student enrollment in such classes. The findings illustrated how concerted efforts provided students with a challenging curriculum, thus, increasing access to advanced mathematics classes for all students. Policies and practices that lifted all students had a positive effect for Black students. / Ed. D.

Mental health in young adults can vary significantly with a large proportion struggling with clinical disorders. Despite the high prevalence of psychopathology, many do not receive help. Relevant barriers to help-seeking include self-reliance, lack of awareness of symptoms or sources of help, and stigma. Measurement Feedback Systems (MFSs) and self-monitoring are potential avenues to assist in treatment engagement. In this study, Bi-Weekly Monitoring with Informational Feedback (BWM) was implemented in a college student population (N = 74) where students were asked to report on their overall psychological functioning and set goals every other week. BWM was evaluated for feasibility, effects on help-seeking overall, and mechanisms of self-monitoring were explored. BWM was determined to be feasible in this population; although, help-seeking attitudes did not change over time as a result of BWM. Ancillary analyses explored the effects of BWM and mental health symptomatology. Participants reported on their attitudes towards BWM which were generally in favor of BWM. Some promising results emerged; however, they were largely statistically insignificant. Limitations of this study include a large drop-out rate in the control group, which left unequal groups. As such, analyses should be interpreted with caution. Future studies should evaluate BWM on a weekly basis with a larger sample to better understand the effects of BWM on self-monitoring mechanisms. / Master of Science / Mental health in young adults can vary significantly with a large proportion struggling with clinical disorders. Despite the high prevalence of psychopathology, many do not receive help. Relevant barriers to help-seeking include self-reliance, lack of awareness of symptoms or sources of help, and stigma. Measurement Feedback Systems (MFSs) and self-monitoring are potential avenues to assist in treatment engagement. In this study, Bi-Weekly Monitoring with Informational Feedback (BWM) was implemented in a college student population (N = 74) where students were asked to report on their overall psychological functioning and set goals every other week. BWM was evaluated for feasibility, effects on help-seeking overall, and mechanisms of self-monitoring were explored. BWM was determined to be feasible in this population; although, help-seeking attitudes did not change over time as a result of BWM. Attitudes towards BWM were variable, yet largely favorable. While some promising results emerged, there has yet to be concrete support for BWM. This study is limited due to a large drop-out rate in the control group, as such the results should be interpreted with caution. Future studies should evaluate BWM on a weekly basis with a larger sample to better understand the effects of BWM on self-monitoring mechanisms.

Landslides cause significant damage worldwide and therefore epitomize the most important problems in geotechnical engineering. Hence, perceiving the mechanics involved in the deformation process of landslides is necessary for risk assessment. In addition to the resistance offered by basal shear surfaces, internal shearing also influences the stability and kinematics of compound landslides. For compound landslides, internal shearing is essential to develop feasible sliding mechanisms. The internal distortion is caused by the formation of shear bands that develop within the sliding mass. The strain localization is generally attributed to slope changes along the basal sliding surface (or topography) that constrain the strain field of the landslide. The development of these internal shear bands also controls the energy dissipation, and its distribution determines the final degradation of the material. This work focuses on the study of internal failure mechanisms that develop in compound landslides. A theoretical model of a compound landslide is numerically analyzed using the Material Point Method (MPM), a state-of-the-art numerical technique appropriate to model large deformation problems. The internal failure pattern is identified for different basal sliding geometries. Based on that, a generalized method is proposed to estimate the internal failure mechanism of bi-planar compound geometries. The material degradation and energy dissipation are evaluated in terms of the accumulated deviatoric strain and the reaction forces exerted by the landslide on a vertical wall. Moreover, preliminary studies are conducted to analyze the use of barriers as a mitigation strategy to counter landslide damage, and their efficiencies are investigated. / Master of Science / Landslides consist of movement of rock and debris down a slope. They cause substantial damage each year and therefore represent an important class of problems in geotechnical engineering. Understanding the deformation process and internal shearing pattern occurring in landslides is an important aspect for assessing the risk that a landslide poses. The internal shear is caused due to the formation of shear bands that develop within the mass flowing down the slope and originate at the points of slope change on an incline. These shear bands also affect the amount of energy dissipated and the degradation of flow material. In this work, the internal failure mechanism in landslides is analyzed and effects on landslide kinematics are studied. Material Point Method (MPM) is used to simulate slope instabilities which is an advanced numerical technique appropriate for modeling large deformation problems such as landslides. Several theoretical models of compound landslides are presented considering variation in geometry (roundedness), friction, and slope angle. A generalized failure mechanism of a landslide is proposed based on its geometry and physical parameters. Finally, accumulated strains and reaction forces impacted by moving mass on a wall are calculated for different landslide geometries, and subsequently correlated to energy dissipation material degradation. These results also serve as a precursor to studying the role of barriers in mitigating landslide damage.